JP7640666B2 - Construction Machinery - Google Patents

Description

The present invention relates to construction machinery such as hydraulic excavators that perform excavation and loading operations, and in particular to construction machinery that has a high degree of freedom in layout or construction machinery that emits low greenhouse gases.

Conventionally, automatic operation has been developed for construction machines such as backhoes, and the automation of excavation work is disclosed in Patent Document 1.
Furthermore, vehicles that emit less greenhouse gases are being developed, and Patent Document 2 discloses the application of fuel cells to backhoes.

JP 2020-41354 A JP 2010-173639 A

However, since the construction machine in Patent Document 1 has a driver's seat, there are limitations on the layout of the construction machine.
Furthermore, although Patent Document 2 discloses details about fuel cells, it does not disclose how to mount the fuel cells on construction machinery. As a result, construction machinery with low greenhouse gas emissions has not been realized.

Therefore, an object of the first invention is to provide a construction machine which allows a high degree of freedom in layout.
Another object of the second invention is to provide a construction machine that emits less greenhouse gases.

The construction machine of the present invention comprises a main body that can be rotated by rotating a rotating part, a working device connected to one end side of the main body, a drive system that drives at least one of the main body and the working device, and a mass body that corrects an unbalanced load acting on the main body by driving the working device, wherein the mass body holds at least a part of the drive system, and the mass body holds a fuel tank for storing fuel, and the drive system comprises the fuel tank and a control unit that moves the mass body depending on the remaining amount of fuel in the fuel tank .
The construction machine of the present invention comprises a main body that can be rotated by rotating a rotating part, a working device connected to one end side of the main body, a drive system that drives at least one of the main body and the working device, a mass body that corrects an unbalanced load acting on the main body by driving the working device, and a leak detection sensor that detects fuel leaks used in the drive system, and is further equipped with a movement control unit that causes the mass body to hold at least a part of the drive system and moves the mass body outside the main body when the leak detection sensor detects a fuel leak.

According to the first aspect of the present invention, since at least a part of the drive system is supported by the mass body, a construction machine with a high degree of freedom in layout can be provided.

1A and 1B are schematic diagrams of a construction machine according to a first embodiment of the present invention, in which FIG. 1A is a top view and FIG. 1B is a front view. FIG. 2 is a schematic diagram of the construction machine when the counter mass of the construction machine of FIG. 3(a) is a view seen from the arrow AA in FIG. 1(b), and FIG. 3(b) is a view seen from the arrow AA in FIG. 2(b). FIG. 2 is a block diagram of the main parts of the first embodiment. 4 is a flowchart executed by the heavy equipment control device of the first embodiment. 6A and 6B are schematic diagrams of a construction machine representing the second embodiment, in which FIG. 6A is a top view and FIG. 6B is a front view. 10 is a flowchart executed by a heavy equipment control device 50 according to the second embodiment. Figure 8 is a diagram showing the excavation operation, where Figure 8(a) shows the working device in the initial position, Figure 8(b) shows the state during excavation, Figure 8(c) shows the state when excavation is completed, and Figure 8(d) shows the state after turning. 9A and 9B are diagrams showing operations following the excavation operation of FIG. 8, with FIG. 9A showing the loading state, FIG. 9B showing the working device in the initial position, FIG. 9C showing the state after the upper main body device has been rotated, and FIG. 9D showing the state during excavation. 10(a) and 10(b) are schematic diagrams of a construction machine according to the third embodiment.

Below, a construction machine according to an embodiment of the present invention will be described in detail with reference to the attached drawings. Note that the present invention is not limited to the embodiment described below. In this embodiment, the explanation will continue with a hydraulic excavator 1 as an example of a construction machine.

First Embodiment
Fig. 1 is a schematic diagram showing a hydraulic excavator 1 representing this embodiment, with Fig. 1(a) being a top view and Fig. 1(b) being a front view. Fig. 2 is a schematic diagram of the construction machine when the counter mass 43 of the hydraulic excavator 1 in Fig. 1(b) has moved in the -X direction. Fig. 3 is a view seen from the arrows A-A in Figs. 1 and 2, Fig. 3(a) is a view seen from the arrows A-A in Fig. 1(b), and Fig. 3(b) is a view seen from the arrows A-A in Fig. 2(b). Fig. 4 is a block diagram of the main parts of this first embodiment.

The configuration of the hydraulic excavator 1 will be described below with reference to Figures 1 to 4. As is clear from Figure 1, the hydraulic excavator 1 of this embodiment is an autonomous type that does not have a driver's seat, and has a UAV (Unmanned Aerial Vehicle, hereinafter referred to as drone 100), which is an unmanned aerial vehicle. The hydraulic excavator 1 may be autonomous when traveling at a construction site, and may be transported on a trailer on public roads. The hydraulic excavator 1 may be operated automatically, or may be remotely operated at a remote location away from the excavation site.

The hydraulic excavator 1 of this embodiment has a drive system 10 (see FIG. 4), a traveling device 20, a slewing device 30, a main body device 40, and a working device 60. The hydraulic excavator 1 also has a drone 100 that can take off and land on a takeoff and landing section provided on the upper surface of the main body device 40. Note that although one drone 100 is shown in FIG. 1(a) and FIG. 1(b), there may be multiple drones 100. The drone 100 may be of a type that flies using electricity, or of a type that flies using a fuel cell that uses hydrogen.

The drive system 10 includes an engine 11, a fuel tank 12, a leak sensor 13, and a generator 14. The engine 11 is an internal combustion engine, and in this embodiment, a diesel engine is used. The engine 11 burns fuel supplied from the fuel tank 12 to drive the generator 14.
In this embodiment, the fuel tank 12 stores liquid ammonia (NH3), and is provided with a fuel level gauge (not shown) inside. The liquid ammonia is vaporized by a vaporizer (not shown), and the vaporized ammonia is burned by the engine 11 together with air. Note that a plurality of fuel tanks 12 may be provided to serve as ammonia storage tanks and diesel storage tanks. In this case, the engine 11 may be a multi-fuel engine that burns ammonia and diesel together.

The leak sensor 13 is a liquid leakage sensor that detects leakage of liquid ammonia stored in the fuel tank 12, or a gas sensor that detects leakage of vaporized ammonia from the vicinity of the engine 11. As a liquid leakage sensor, there are a contact detection method in which electricity flows by conduction through the liquid when the liquid contacts two electrodes, and a non-contact detection method in which a fiber sensor is used to detect leakage by reflection and transmission, and various types of sensors can be used as appropriate. As a gas sensor, there are a solid-state sensor using a semiconductor, a constant-potential electrolytic electrochemical sensor, an optical sensor using infrared rays, and any of these sensors can be used. Note that both a liquid leakage sensor and a gas sensor may be installed as the leak sensor 13, or either one of them may be installed.

The generator 14 is connected to the output shaft of the engine 11 and generates electricity using the rotational driving force of the output shaft of the engine 11. The electricity generated by the generator 14 is supplied to various cylinders and motors, as shown in the block diagram of FIG. 4. In addition, although details will be described later, in this embodiment, the engine 11, fuel tank 12, and generator 14 are placed on a counter mass 43, which will be described later. In addition, depending on the movement of the counter mass 43, the engine 11, fuel tank 12, and generator 14 may be exposed to the outside of the main unit 40, so they are covered by a cover 19.

The traveling device 20 has a pair of tracks 23 wound around an idler wheel 21 and a drive wheel 22, and a traveling motor (not shown) that drives the drive wheel 22, and the pair of tracks 23 are driven by the drive wheel 22 to travel the hydraulic excavator 1. The traveling motor 24 is driven by power supplied from the generator 14, and in this embodiment, an in-wheel motor is used that is coaxially connected to the drive wheel 22 or the hub of the drive wheel 22.

The slewing device 30 is disposed on the traveling device 20 and the main device 40. The slewing device 30 is equipped with a bearing (not shown) and a slewing motor 31 supplied with power from the generator 14, and rotates the main device 40 and the working device 60. Note that the slewing device 30 may rotate the main device 40 and the working device 60 using hydraulic pressure instead of the slewing motor 31.

The main body device 40 has a flat top surface, and on this top surface are a power transmission device 15 that supplies power to the drone 100, and a shield member 16.
In addition, the power transmission device 15 on the top surface of the main body device 40 serves as the takeoff and landing part of the drone 100.

The power transmitting device 15 supplies power to a power receiving device 103 (described later) of the drone 100, and in this embodiment, wireless power feeding is adopted. Wireless power feeding supplies power to the power receiving device 103 in a non-contact manner, and a magnetic resonance method, an electromagnetic induction method, etc. are known. The power transmitting device 15 in this embodiment includes a power source, a control circuit, and a power transmitting coil.
The power transmitting device 15 may be of a spatial transmission type instead of the above-mentioned proximity junction type. Spatial transmission type power supply uses electromagnetic waves such as microwaves to supply power to a target object (the power receiving device 103 of the drone 100 in this embodiment) located several meters to several tens of meters away.

In addition, a contact-type power supply method may be used instead of wireless power supply. In this case, metal contacts may be provided on each of the power transmitting device 15 and the power receiving device 103, and the contacts may be mechanically connected to supply power. For example, a concave-shaped contact may be provided on the takeoff and landing section, and a convex-shaped contact may be provided on the drone 100 side. There may be one each of the concave-shaped contact and the convex-shaped contact, or multiple may be provided.

The shielding member 16 shields electromagnetic noise, and in this embodiment, the shielding member 16 prevents electromagnetic noise generated from the power transmission device 15 and the like from affecting the antenna 48a described later. As shown in FIG. 1(a), the shielding member 16 is provided to surround the power transmission device 15, and also surrounds the drone 100 when the drone 100 lands on the takeoff and landing section. The shielding member 16 does not surround the entire drone 100, but only needs to be able to shield electromagnetic noise that may be generated from the battery 105 and the second communication device 106 described later. For this reason, the shielding member 16 surrounds the power transmission device 15 and at least a part of the drone 100. For example, permalloy, which is an alloy of nickel (Ni) and iron (Fe), can be used as the shielding member 16.

The main body 40 is connected to the work device 60 via the swing section 41 and the swing cylinder 42 on the side. In addition to the engine 11, fuel tank 12, leak sensor 13, and generator 14 described above, the main body 40 includes an attitude detector 18, a counter mass 43, a pair of sliders 44, a pair of bases 45, a counter mass motor 46, a first GNSS 47 (Global Navigation Satellite System) which is a global positioning system, a first communication device 48, a first memory 49, and a heavy equipment control device 50 which controls the entire hydraulic excavator 1. The main body 40 also has an opening (not shown) for the cover 19 and the counter mass 43 to move to the outside of the main body 40. An opening/closing part for opening and closing this opening may be provided. When this opening/closing part is provided, the cover 19 may be omitted.

The attitude detector 18, which is not shown in Figures 1(a) and 1(b), is a sensor that is attached inside the main unit 40 and detects the attitude of the main unit 40. An inclinometer, a spirit level, or the like can be used as the attitude detector 18.

The counter mass 43 corrects the unbalanced load acting on the hydraulic excavator 1 when the working device 60 is driven, and is provided on the main unit 40 so as to be on the opposite side of the working device 60. The counter mass 43 is provided on the lower side of the main unit 40 and is attached to a pair of sliders 44 spaced apart in the Y direction. The pair of sliders 44 extend in the X direction and are supported by a pair of bases 45 so as to be movable in the X direction. While the conventional counter mass is provided along the Z direction, which is the vertical direction, the counter mass 43 of this embodiment is provided along the XY plane perpendicular to the Z direction. This allows the center of gravity of the hydraulic excavator 1 to be lowered.

The counter mass motor 46 moves the counter mass 43 by moving a pair of sliders 44 along a pair of bases 45. When the working device 60 is located on the +X side, the counter mass 43 moves to the -X side, and when the working device 60 is located on the -X side due to the rotation of the swivel device 30, the counter mass 43 moves to the +X side. Note that when the working device 60 is located on the +Y side, the counter mass 43 moves to the -Y side.

The size of the hydraulic excavator 1 depends on the size of the bucket 58, and the size and weight of the engine 11, fuel tank 12, generator 14, and counter mass 43 that constitute the hydraulic excavator 1 also depend on the size of the bucket 58. For this reason, depending on the size of the bucket 58, a weight of about 1.5 tons to 4 tons is required to correct the unbalanced load acting on the hydraulic excavator 1 when the working device 60 is driven. Here, the weight of the engine 11 is about 350 kg to 600 kg, the weight of the fuel tank 12 when full is about 120 kg to 400 kg, and the weight of the generator 14 is about 450 kg to 750 kg. The total weight of these is about 920 kg to 1750 kg, so the weight required for the counter mass 43 is about 580 kg to 2750 kg. By placing the engine 11, fuel tank 12, and generator 14 on the counter mass 43, the weight of the counter mass 43 can be reduced. It should be noted that the counter mass 43 does not need to carry all of the engine 11, the fuel tank 12, and the generator 14, but only needs to carry at least one of the engine 11, the fuel tank 12, and the generator 14. Therefore, the counter mass 43 and anything placed on the counter mass 43 become mass bodies for correcting the unbalanced load acting on the hydraulic excavator 1.

When the counter mass 43 carries the fuel tank 12, the weight of the fuel tank 12 becomes lighter as fuel is used. In such a case, the weight of the counter mass 43 may be set assuming that the fuel tank 12 is empty, and the counter mass 43 may be moved by the counter mass motor 46 as fuel is used. When the counter mass 43 is moved by the counter mass motor 46, the weight of the counter mass 43 may be further reduced. In addition, when the counter mass 43 is not moved, the pair of sliders 44, the pair of bases 45, and the counter mass motor 46 may be omitted. However, even when the counter mass 43 is not moved, if the pair of sliders 44, the pair of bases 45, and the counter mass motor 46 are used to pull out the engine 11, the fuel tank 12, and the generator 14 to the outside of the main unit 40, maintenance of the engine 11 and the generator 14 becomes easier, and fuel supply to the fuel tank 12 becomes easier. The movement of the counter mass 43 may be achieved by using an actuator of another driving method, such as a hydraulic actuator, instead of the counter mass motor 46 .

The swing section 41 is supported such that a portion connected to the main unit 40 and a portion connected to the boom 53 are rotatable around the Z axis. The swing cylinder 42 is a cylinder having one end connected to the main unit 40 and the other end connected to the swing section 41, and is extended and retracted by power supplied from the generator 14.
By extension and contraction of the swing cylinder 42, the working device 60 is driven in a clockwise or counterclockwise direction in FIG.

The boom cylinder 54 is a cylinder that extends and retracts using power supplied from the generator 14 to drive the boom 53 .
The arm cylinder 56 is a cylinder that extends and retracts using power supplied from the generator 14 to drive the arm 55 .
The bucket cylinder 59 is a cylinder that extends and retracts using power supplied from the generator 14 to drive the bucket 58 .
In this embodiment, the swing cylinder 42, the boom cylinder 54, the arm cylinder 56, and the bucket cylinder 59 are driven by electric power from the generator 14, but these cylinders may also be driven using hydraulic pressure.

The first GNSS 47 measures the position of the hydraulic excavator 1 by using an artificial satellite.
The first communication device 48 has an antenna 48a, a transmitter, a receiver, various circuits, etc., and is a wireless communication unit that accesses a second communication device 106 described below or a wide area network such as the Internet. In this embodiment, the first communication device 48 communicates the flight path of the drone 100 to the second communication device 106 based on the position of the hydraulic excavator 1 detected by the first GNSS 47. Note that, although two antennas 48a are illustrated in Fig. 1, the number may be one, or three or more.

The first memory 49 is a non-volatile memory (e.g., a flash memory) and stores various data and programs for driving the hydraulic excavator 1 and various data and programs for automatically operating the hydraulic excavator 1. The first memory 49 also stores data regarding the flight path of the drone 100.

The heavy equipment control device 50 is equipped with a CPU and is a control device that controls the entire hydraulic excavator 1. For example, it controls the excavation operation and turning operation of the work device 60, the movement of the counter mass 43, and the flight operation of the drone 100.

The main unit 40 is connected to the work device 60 via a swing section 41 and a swing cylinder 42. The work device 60 has a boom 53, a boom cylinder 54, an arm 55, an arm cylinder 56, a bucket 58, and a bucket cylinder 59.

The boom 53 is a U-shaped part connected to the main body device 40 via the swing portion 41 , and is rotated by a boom cylinder 54 .
The arm 55 is connected to the tip of the boom 53 and is rotated by an arm cylinder 56 .
The bucket 58 is connected to the tip of the arm 55, and is rotated by a bucket cylinder 59. Note that instead of the bucket 58, a breaker or the like can be attached to the tip of the arm 55.

The drone 100 of this embodiment includes a flying device 101, an imaging device 102, a power receiving device 103, a group of sensors 104, a battery 105, a second communication device 106, a second memory 107, and a UAV control device 108.
The flight device 101 has a motor (not shown) and multiple propellers, and generates thrust to lift the drone 100 in the air and move it in the air. As described above, the number of drones 100 that land on the takeoff and landing section can be set arbitrarily. The configuration of each drone 100 may be the same or may be partially changed. Furthermore, the size of each drone 100 may be the same or may be different.

The imaging device 102 is a digital camera that has a lens, an imaging element, an image processing engine, etc., and captures moving images and still images. In this embodiment, the imaging device 102 is used to conduct surveying and capture images of excavation sites.

In the enlarged view surrounded by the dashed line in FIG. 2, the lens of the imaging device 102 is attached to the side (front) of the drone 100, but the lens of the imaging device 102 may be attached to the underside of the drone 100, or multiple lenses may be provided on the drone 100. Also, a moving mechanism may be provided to move the lens attached to the side toward the underside. Also, a mechanism may be provided to rotate the imaging device 102 around the Z axis so that the lens of the imaging device 102 can be positioned at any position around the Z axis. Note that an omnidirectional camera (360-degree camera) may be used as the imaging device 102, and a three-dimensional scanner may be used instead of the imaging device 102.

The power receiving device 103 has a power receiving coil and a charging circuit provided on the leg 109 of the drone 100, and charges the battery 105 with power from the power transmitting device 15.
The battery 105 is a secondary battery connected to the power receiving device 103, and may be, but is not limited to, a lithium ion secondary battery, a lithium polymer secondary battery, etc. The battery 105 is capable of supplying power to the flight device 101, the imaging device 102, the second communication device 106, the second memory 107, and the UAV control device 108.

The sensor group 104 includes a GNSS, an infrared sensor for avoiding collisions between the drone 100 and other devices (e.g., the work device 60), a barometric pressure sensor for measuring altitude, a magnetic sensor for detecting direction, a gyro sensor for detecting the attitude of the drone 100, and an acceleration sensor for detecting the acceleration acting on the drone 100.

The second communication device 106 has a wireless communication unit and accesses a wide area network such as the Internet and communicates with the first communication device 48. In this embodiment, the second communication device 106 transmits image data captured by the imaging device 102 and detection results detected by the sensor group 104 to the first communication device 48, and transmits flight commands from the first communication device 48 to the UAV control device 108.

The second memory 107 is a non-volatile memory (e.g., a flash memory) that stores various data and programs for flying the drone 100, as well as image data captured by the imaging device 102 and detection results detected by the sensor group 104.

The UAV control device 108 includes a CPU, an attitude control circuit, a flight control circuit, and the like, and controls the entire drone 100. The UAV control device 108 also determines the timing of charging the takeoff and landing section based on the remaining charge of the battery 105, and controls the imaging position, angle of view, frame rate, and the like of the imaging device 102.

In the hydraulic excavator 1 of this embodiment configured as described above, the drone 100 surveys the excavation area prior to excavation by the working device 60, and during excavation by the working device 60, images can be taken from the sky and images of the bucket near the bucket 58, so excavation can be performed even if the operator is not in the excavation area. Furthermore, if the drone 100 takes images at the takeoff and landing section, images can be taken from approximately the same position as the driver's seat of a conventional hydraulic excavator.

By using multiple drones 100, the second drone 100 can be charged at the takeoff and landing area while the first drone 100 is flying, so the first drone 100 and the second drone 100 can fly alternately. The number of drones 100 may be three or more.

The following is a further explanation of the control of excavation operations by the heavy equipment control device 50 of this embodiment configured as described above. Figure 5 is a flowchart executed by the heavy equipment control device 50 of this embodiment. Note that the flowchart in Figure 5 is executed when the drive system 10 is operating.

(flowchart)
The heavy equipment control device 50 judges whether or not an abnormality occurs in the hydraulic excavator 1 (step S1). Here, the heavy equipment control device 50 judges whether or not ammonia is leaking from the output of the leak sensor 13, and if ammonia is not leaking, proceeds to step S2, and if ammonia is leaking, proceeds to step S6 to stop the hydraulic excavator 1. When ammonia is leaking and the hydraulic excavator 1 is stopped, the heavy equipment control device 50 opens an opening (not shown) in the main unit 40 so that ammonia does not remain in the main unit 40 in a high concentration state. The heavy equipment control device 50 may move a part of the engine 11 and the fuel tank 12 to the outside of the main unit 40 by driving the counter mass motor 46 to move the counter mass 43. This reduces the ammonia concentration in the main unit 40 and improves the maintainability of the engine 11 and the fuel tank 12. Also, an opening (not shown) may be provided in the cover 19, and when ammonia is leaking, the opening (not shown) may be opened by a motor (not shown). It is desirable to open this opening (not shown) when a part of the counter mass 43 comes out to the outside of the main body device 40.

Here, it is assumed that there is no ammonia leak, and the heavy equipment control device 50 proceeds to step S2.
The heavy equipment control device 50 performs excavation using the working device 60 based on the program for automatic operation of the working device 60 stored in the first memory 49, for example, based on the survey results obtained using the drone 100 (step S2). The program for automatic operation of the working device 60 is executed based on the position of the hydraulic excavator 1 measured by the first GNSS 47, the height of the excavated material at the excavation point, the excavation range of the working device 60, and other factors. This program also includes control of the traveling device 20, the swivel device 30, the swing cylinder 42, and the like. Note that the excavation in step S2 may be performed by remote operation by a worker at a remote location instead of automatic operation.

The heavy equipment control device 50 determines whether the unbalanced load acting on the hydraulic excavator 1 due to the driving of the working device 60 in step S2 needs to be corrected by driving the counter mass 43 (step S3). In this embodiment, the weight of the counter mass 43 is set so that the movement of the counter mass 43 due to the driving of the working device 60 is not required when the fuel tank 12 is full.

The heavy equipment control device 50 makes the decision in step S3 based on the output of a fuel gauge (not shown) provided in the fuel tank 12. If the remaining amount of fuel in the fuel tank 12 is, for example, less than 50%, the heavy equipment control device 50 proceeds to step S4. If the remaining amount of fuel in the fuel tank 12 is 50% or more, the heavy equipment control device 50 proceeds to step S5, which will be described later. Note that the heavy equipment control device 50 may make the decision as to whether to move the counter mass 43 based on the output of the attitude detector 18, instead of or in combination with the output of the fuel gauge (not shown).

The heavy equipment control device 50 drives the counter mass motor 46 to move the counter mass 43 together with the engine 11, fuel tank 12, and generator 14 (step S4). It is preferable to provide an alarm on the main unit 40 to prevent accidents when the counter mass 43 moves outside the main unit 40. For example, it is preferable to provide a warning light on the main unit 40 to visually alert the user, or a speaker on the main unit 40 to audibly alert the user, or to do both.

The heavy equipment control device 50 determines whether the work by the working device 60 has been completed (step S5). The heavy equipment control device 50 repeatedly executes steps S1 to S5 until the scheduled excavation work is completed, and proceeds to step S6 when the scheduled excavation work is completed.

When the work by the working device 60 is completed, the heavy equipment control device 50 performs control to stop the hydraulic excavator 1 (step S6). Specifically, the heavy equipment control device 50 moves the working device 60 to the initial position, and when the counter mass 43 has been moved to the outside of the main body device 40, moves the counter mass 43 to the inside of the main body device 40. The initial position refers to the time when the working device 60 is in a position where an unbalanced load is unlikely to occur (i.e., a position where the portion extending in the X direction is small).
The heavy equipment control device 50 moves the hydraulic excavator 1 by the traveling device 20 as necessary, and then stops the driving of the hydraulic excavator 1, and ends this flowchart.

In this embodiment, the counter mass 43 is provided along the XY plane perpendicular to the Z direction by utilizing the space vacated by the operator's seat, and the engine 11, fuel tank 12, and generator 14 are placed (held) on the counter mass 43, thereby reducing the weight of the counter mass 43 and realizing a hydraulic excavator 1 with high layout freedom. Note that, although the fuel tank 12 is disposed on the other end side (-X side) of the main unit 40 in Figures 1 to 3, the engine 11 may be disposed on the other end side of the main unit 40, and the generator 14 may be disposed on the other end side of the main unit 40.

In addition, an ammonia concentration meter may be provided in the main unit 40, and when the ammonia concentration exceeds, for example, 20 ppm, the aforementioned alarm may provide a visual or audible alarm. In addition, a solar power generation device may be provided on the top or side of the main unit 40, and the electricity generated by this solar power generation device may be used to drive the hydraulic excavator 1. The solar power generation device may be, for example, a perovskite solar cell. A perovskite solar cell is a solar cell that uses perovskite crystals, and is flexible so that it can be attached to structures with curved surfaces. In addition, since perovskite solar cells are lightweight, the increase in weight of the hydraulic excavator 1 can be suppressed.

Furthermore, a construction machine that emits less greenhouse gases can be realized when ammonia or the like that does not emit greenhouse gases is used as fuel for the engine 11. However, if the situation allows the emission of greenhouse gases, diesel or gasoline may be used instead of ammonia.
When the generator 14 is placed on the counter mass 34, the lengths of the wiring for the various cylinders and motors to which power is supplied from the generator 14 may be increased in consideration of the movement stroke of the counter mass 34. Alternatively, the power supply from the generator 14 to the various cylinders and motors may be a space-transmission type power supply (wireless power supply).

Second Embodiment
The second embodiment will be described below with reference to Figures 6 to 9. The same components as those in the first embodiment are denoted by the same reference numerals, and their description will be omitted or simplified. In Figure 6, the shield member 16, the cover 19, the antenna 48a, the drone 100, and the like are omitted in order to avoid complicating the drawing.
FIG. 6 is a schematic diagram of a hydraulic excavator 1 which is an example of a construction machine representing the second embodiment, in which FIG. 6( a) is a top view and FIG. 6( b) is a front view, and the portion surrounded by the dotted line is shown as a partial cross-sectional view.

In the hydraulic excavator 1 of the second embodiment, the slewing device 30 and the main body device 40 are divided into two, and there are two working devices 60. The two slewing devices 30 are described as an upper slewing device 30a and a lower slewing device 30b. The slewing motor 31 of the first embodiment is divided into two, an upper slewing motor 31a and a lower slewing motor 31b. Similarly, the two main body devices 40 are described as an upper main body device 40a and a lower main body device 40b. The configuration of the two working devices 60 is the same as in the first embodiment, so one is referred to as a working device 60a and the other is referred to as a working device 60b, and the elements constituting the working devices 60a and 60b are also labeled with a or b after the reference numerals.

The upper main body device 40a can be rotated by the upper rotating device 30a having a bearing. The upper main body device 40a also functions as a storage section, and stores the engine 11, fuel tank 12, generator 14, counter mass 43, and part of the upper rotating motor 31a for rotating the upper main body device 40a. The counter mass 43 is rectangular in the first embodiment, but is circular in this embodiment, and the engine 11 and generator 14 are placed on one end side (the -X side in Figures 6(a) and 6(b)). The shape of the counter mass 43 can be set arbitrarily.

Furthermore, in this embodiment, since two working devices 60 are provided, for example, the unbalanced load acting on the hydraulic excavator 1 due to the driving of the working device 60b can be corrected by the load of the working device 60a. In particular, if the working device 60a is moved to the -X direction, the unbalanced load acting on the hydraulic excavator 1 due to the driving of the working device 60a can be corrected more effectively. For this reason, since the unbalanced load is corrected by the load of the engine 11 and the generator 14 arranged on one end side of the counter mass 43, it is possible to reduce the weight of the counter mass 43 or to omit the counter mass 43. Note that the unbalanced load may be corrected by placing only one of the engine 11 and the generator 14 on the counter mass 43.
In this embodiment, the fuel tank 12 is cylindrical and contributes to stabilizing the weight balance of the upper main body device 40a rather than correcting the unbalanced load. For this reason, the fuel tank 12 is not placed on the counter mass 43. Since the fuel tank 12 is used to stabilize the weight balance of the upper main body device 40a, the reduction in fuel in the fuel tank 12 does not affect the correction of the unbalanced load. Although not shown in Figures 6(a) and 6(b), it is preferable to provide the attitude detector 18 in the upper main body device 40a.

An opening is formed in the center of the lower part of the upper main body device 40a, and an upper slip ring 35, which constitutes part of the slip ring mechanism described below, engages with this opening. The upper slip ring 35 has an opening through which wiring that supplies power to the lower rotation motor 31b and the travel motor 24 is routed. A part of the upper slip ring 35 rotates in conjunction with the rotation of the upper main body device 40a.

In addition to the upper slip ring 35, the slip ring mechanism has a lower slip ring 36 and a fixed part 37 connected to the non-rotating part of the upper slip ring 35 and the non-rotating part of the lower slip ring 36. The lower slip ring 36 is provided on the lower main body device 40b and supports the fixed part 37 from the outside. The fixed part 37 is provided so as to penetrate the lower rotating device 30b and has an opening for drawing wiring from the upper slip ring 35. Therefore, even if the upper main body device 40a or the lower main body device 40b rotates, the wiring is drawn by the slip ring mechanism, so the wiring will not become tangled or broken. If necessary, piping for liquids (hydraulic pressure or water) or gas may be drawn using this slip ring mechanism.

The lower main body device 40b can be rotated by a lower rotating device 30b having a bearing. The lower main body device 40b is connected to a working device 60a on the -X direction side via a swing section 41a and a swing cylinder 42a, and to a working device 60b on the +X direction side via a swing section 41b and a swing cylinder 42b. It is preferable that the working devices 60a and 60b are arranged symmetrically with respect to the lower main body device 40b. Also, by connecting the working devices 60a and 60b to the lower main body device 40b, the center of gravity of the hydraulic excavator 1 can be prevented from becoming high.

The lower main body device 40b houses a part of the lower swing motor 31b and the lower slip ring 36, and has an opening formed near the center for passing through the fixed part 37. As is clear from FIG. 6B, a large space is formed inside the lower main body device 40b. For this reason, the lower main body device 40b may house maintenance tools for the hydraulic excavator 1, various replacement parts, the drone 100, and replacement parts for the drone 100. In addition, when the various cylinders are hydraulically driven, a hydraulic unit may be disposed inside the lower main body device 40b.
It should be noted that the upper main body device 40a and the lower main body device 40b are not limited to being cylindrical, but may be of any shape.

In this embodiment, when the counter mass 43 is moved to the outside of the upper main body device 40a, the fuel tank 12 is placed on the counter mass 43 and the counter mass 43 is driven by the counter mass motor 46. In addition, when it is not necessary to move the counter mass 43 to the outside of the upper main body device 40a, the pair of sliders 44, the pair of bases 45, and the counter mass motor 46 can be omitted.

(Flowchart explanation)
Fig. 7 is a flow chart executed by the heavy equipment control device 50 of this embodiment, Fig. 8 is a diagram showing the excavation operation, Fig. 8(a) is a diagram showing the working device 60 in the initial position, Fig. 8(b) is a diagram showing the state during excavation, Fig. 8(c) is a diagram showing the state when excavation is completed, and Fig. 8(d) is a diagram showing the state after turning. Fig. 9 is a diagram showing the operation following the excavation operation of Fig. 8, Fig. 9(a) is a diagram showing the loading state, Fig. 9(b) is a diagram showing the working device 60 in the initial position, Fig. 9(c) is a diagram showing the state after the upper main body device 40a has been turned, and Fig. 9(d) is a diagram showing the state during excavation.

The flowchart of FIG. 7 will be described below with reference to FIG. 8 and FIG. 9. In FIG. 8 and FIG. 9, the portion surrounded by the dotted line is shown as a partial cross-sectional view, as in FIG. 6. In FIG. 8 and FIG. 9, some of the reference symbols are omitted to avoid complicating the drawings. In this embodiment, the initial position refers to the state when the two working devices 60 are in a position where the unbalanced load is unlikely to occur (i.e., a position where the portion extending in the X direction is small). In the flowchart of FIG. 7, a part of it may be performed by a worker in a remote location, for example, away from the civil engineering site.

The heavy equipment control device 50 determines whether the hydraulic excavator 1 is ready to excavate (step S11). As shown in FIG. 8(a), if the hydraulic excavator 1 has arrived at the excavation site and is ready to excavate, and the dump truck 70 has arrived at the loading site, the heavy equipment control device 50 determines that excavation preparation is complete and proceeds to step S12, otherwise repeats step S11. Here, it is assumed that excavation preparation is complete and proceeds to step S12.

As shown in FIG. 8(b), the heavy equipment control device 50 performs excavation using the bucket 58a that constitutes part of the working device 60a (step S12). When performing excavation using the bucket 58a, the heavy equipment control device 50 flies the drone 100 near the bucket 58a and captures the excavation operation of the bucket 58a with the imaging device 102, thereby enabling the excavation status to be confirmed. In this embodiment, the working device 60a and the working device 60b have the same configuration, and therefore the same weight. However, as shown in FIG. 8(b), when the working device 60a extends in the -X direction and the excavated material is stored in the bucket 58a, an unbalanced load in the -X direction acts on the hydraulic excavator 1. Therefore, in this embodiment, this unbalanced load is corrected by positioning the engine 11 and the generator 14, which are housed in the upper main body device 40a and placed by the counter mass 43, in the +X direction.

The heavy equipment control device 50 judges whether excavation by the bucket 58a has ended (step S13). When the heavy equipment control device 50 judges that a predetermined amount of excavated material is contained in the bucket 58a based on the image captured by the imaging device 102 of the drone 100, the heavy equipment control device 50 judges that excavation by the bucket 58a has ended. Alternatively, a worker at a remote location may judge whether excavation by the bucket 58a has ended based on the image captured by the imaging device 102 of the drone 100. Also, a weight scale may be provided in the bucket 58a, and the heavy equipment control device 50 may judge whether a predetermined amount of excavated material is contained in the bucket 58a based on the measurement result of the weight scale. Here, it is assumed that excavation by the bucket 58a has ended and the process proceeds to step S14. When the heavy equipment control device 50 judges that excavation by the bucket 58a has ended, it moves the working device 60a to the initial position as shown in FIG. 8(c). This is to reduce the unbalanced load acting on the lower body device 40b, etc. due to the rotation of the working device 60a in step S14, and to perform the rotation safely.

The heavy equipment control device 50 rotates the upper main body device 40a 180 degrees using the upper rotation motor 31a, and rotates the lower main body device 40b 180 degrees using the lower rotation motor 31b (step S14). The lower main body device 40b is rotated in order to load the excavated material stored in the bucket 58a onto the dump truck 70 and to move the bucket 58b, which constitutes part of the work device 60b, to the excavation position. The upper main body device 40a is rotated in order to correct the unbalanced load acting on the hydraulic excavator 1 due to the rotation of the lower main body device 40b. This makes it possible to prevent the hydraulic excavator 1 from floating or tipping over when the lower main body device 40b is rotated. In order to reduce the unbalanced load acting on the hydraulic excavator 1, it is preferable that the rotation directions of the upper main body device 40a and the lower main body device 40b are the same. Specifically, when the upper main body device 40a rotates clockwise, the heavy equipment control device 50 also rotates the lower main body device 40b clockwise. Fig. 8(d) is a diagram showing a state in which the rotation in step S14 has been performed, with the bucket 58a positioned on the +X side, and the bucket 58b and the fuel tank 12 positioned on the -X side.

As shown in FIG. 9(a), the heavy equipment control device 50 drives and controls the working device 60a to load the excavated material stored in the bucket 58a onto the dump truck 70 (step S15). At this time, the heavy equipment control device 50 flies the drone 100 near the bucket 58a and allows the imaging device 102 to capture an image of the loading operation by the bucket 58a, thereby enabling the loading operation to be confirmed. Note that in step S15, the heavy equipment control device 50 may fine-tune the position of the working device 60a using the swing section 41a and the swing cylinder 42a.

The heavy equipment control device 50 determines whether the loading operation using the bucket 58a has been completed based on the image captured by the image capture device 102 or the measurement results of the weighing scale (step S16). Note that this determination in step S16 may be made by a worker in a remote location. When the loading operation is completed, the heavy equipment control device 50 moves the working device 60a to the initial position as shown in FIG. 9(b).

The heavy equipment control device 50 rotates the upper main body device 40a 180 degrees in preparation for excavation work by the working device 60b (step S17). By rotating the upper main body device 40a 180 degrees, the engine 11 and the generator 14 are positioned on the +X direction side as shown in FIG. 9(c), so that the unbalanced load acting on the hydraulic excavator 1 due to the excavation operation of the working device 60b can be corrected. In addition, by moving the working device 60a to the initial position shown in FIG. 9(b) and rotating the upper main body device 40a almost simultaneously, the excavation work by the working device 60b can be started sooner. Furthermore, while moving the working device 60a to the initial position and rotating the upper main body device 40a, the working device 60b may be moved from the initial position to the excavation position. This allows the excavation work by the working device 60b to start sooner. In this way, when the working device 60b is moved from the initial position to the excavation position, since no excavated material is contained in the bucket 58b, no large unbalanced load acts on the hydraulic excavator 1. Incidentally, the unbalanced load correction of the hydraulic excavator 1 by rotating the upper main body device 40a is also possible when an unexpected load acts on the hydraulic excavator 1. In such a case, the heavy machine control device 50 may simply rotate the upper main body device 40a based on the output of the attitude detector 18.

The heavy equipment control device 50 determines whether the predetermined amount of excavation has been completed (step S18). Here, the heavy equipment control device 50 returns to step S12 assuming that the predetermined amount of excavation has not yet been completed. The heavy equipment control device 50 then performs a series of excavation operations using the working device 60b, and then alternates between excavation using the working device 60a and excavation using the working device 60b until the predetermined amount of excavation is reached. The program for executing the flowchart of FIG. 7 is stored in the first memory 49. Step S1 of the flowchart of FIG. 5 may be added to the flowchart of FIG. 7 to detect abnormalities such as ammonia leakage.

As described above, according to the second embodiment, excavation by the working device 60a and excavation by the working device 60b are alternately repeated, so that the construction period of the excavation work can be shortened. Although one drone 100 is illustrated in Figs. 8 and 9, the flowchart of Fig. 7 may be executed by multiple drones 100. Furthermore, the imaging device 102 of the drone 100 may capture images not only during flight, but also when the drone 100 lands on the landing section of the upper main body device 40a. Images captured by the imaging device 102 from the landing section of the upper main body device 40a can be used as images viewed by the worker from the conventional driver's seat.

In addition, when flying the drone 100 near the bucket 58, the UAV control device 108 can avoid a collision between the bucket 58 and the drone 100 by recognizing the bucket 58 using the infrared sensor of the sensor group 104.
Furthermore, the heavy equipment control device 50 may be configured to capture images using the imaging device 102 of the drone 100 in order to determine whether or not a breakdown occurs in the hydraulic excavator 1 or maintenance is required. In this embodiment as well, a hydraulic excavator 1 with low greenhouse gas emissions can be realized.

Third Embodiment
10(a) and 10(b) are schematic diagrams of a hydraulic excavator 1 representing an example of a construction machine representing the third embodiment, and show a part surrounded by a dotted line as a partial cross-sectional view. In addition, in order to avoid complicating the drawings, the shield member 16, the cover 19, the antenna 48a, the drone 100, and the like are omitted from Fig. 10(a) and Fig. 10(b). Hereinafter, the third embodiment will be described with reference to Fig. 10(a) and Fig. 10(b), but the same reference numerals are used to designate the same components as those in the first and second embodiments, and the description thereof will be omitted or simplified.

The third embodiment differs from the second embodiment in that the engine 11 and the generator 14 are disposed closer to the periphery of the upper main body device 40a than the fuel tank 12. Also, in the third embodiment, the engine 11, the fuel tank 12, and the generator 14 are mounted on the counter mass 43. Therefore, the third embodiment differs from the second embodiment in that the fuel tank 12 is used as a mass body for correcting the unbalanced load acting on the hydraulic excavator 1. Therefore, the weight of the counter mass 43 in the third embodiment can be made lighter than the weight of the counter mass 43 in the second embodiment.

As in the first embodiment, the counter mass 43 may be moved to the outside of the upper main body device 40a by the counter mass motor 46. This allows maintenance of the engine 11, generator 14, etc. to be performed outside the upper main body device 40a.

In the second and third embodiments, the upper main body device 40a is used as a storage unit, and the two working devices 60 are connected to the lower main body device 40b via the swing unit 41 and the swing cylinder 42. Alternatively, the lower main body device 40b may be used as a storage unit, and the two working devices 60 may be connected to the upper main body device 40a via the swing unit 41 and the swing cylinder 42.

According to the first to third embodiments, the drone 100 assists the hydraulic excavator 1, so that automated civil engineering work can be efficiently realized. In the first to third embodiments, the hydraulic excavator 1 is driven by supplying ammonia to the engine 11, but instead, the hydraulic excavator 1 may be driven using hydrogen and a fuel cell. In this case, high-pressure hydrogen gas may be stored in the fuel tank 12, and the hydrogen gas may be supplied to the fuel cell. Also, a fuel tank storing hydrogen gas or a fuel cell may be placed on the counter mass 43. The hydraulic excavator 1 may also be driven using methane.

The above-described embodiments are merely examples for explaining the present invention, and various modifications can be made without departing from the scope of the present invention. For example, if an infrared camera is used as the imaging device 102, a series of construction works such as excavation and loading (discharging) can be performed even at night, thereby shortening the construction period. A breaker, fork, ripper, or lifter may be attached to the first arm 63 instead of the first bucket. The first to third embodiments may also be combined as appropriate.

REFERENCE SIGNS LIST 1 Hydraulic excavator 10 Drive system 11 Engine 12 Fuel tank 30 Swing device 30a Upper swing device 30b Lower swing device 40 Main device 40a Upper main device 40b Lower main device 43 Counter mass 50 Heavy equipment control device 60 Work device 51 Power transmission device 100 Drone 102 Imaging device 103 Power receiving device

Claims (9)

A main body portion that can be turned by turning a turning portion;
A working device connected to one end side of the main body portion;
a drive system that drives at least one of the main body and the working device;
a mass body that corrects an unbalanced load acting on the main body portion due to driving of the working device,
The mass supports at least a portion of the drive system ;
the mass holds a fuel tank for storing fuel;
The drive system of the construction machine includes the fuel tank and a control unit that moves the mass body depending on the remaining amount of fuel in the fuel tank . The drive system includes an engine.
2. The construction machine of claim 1, wherein said mass supports said engine. 3. The construction machine according to claim 1 , wherein the fuel tank stores a fuel that does not emit greenhouse gases. The drive system includes a generator for providing electrical power;
The construction machine according to any one of claims 1 to 3 , wherein the mass body supports the generator. The construction machine according to claim 1 , wherein the mass body moves in response to movement of the working implement. A main body portion that can be turned by turning a turning portion;
A working device connected to one end side of the main body portion;
a drive system that drives at least one of the main body and the working device;
a mass body that corrects an unbalanced load acting on the main body due to driving of the working device;
a leak detection sensor for detecting a leak of fuel utilized in the drive system;
The mass supports at least a portion of the drive system;
A construction machine comprising a movement control unit that moves the mass body to the outside of the main body when the leak detection sensor detects a fuel leak. 7. The construction machine according to claim 6 , wherein the leak detection sensor detects the fuel in a gaseous state. The construction machine according to any one of claims 1 to 7 , further comprising an alarm that notifies the user that the mass body is moving. A takeoff and landing unit provided in the main body unit and capable of taking off and landing an unmanned aerial vehicle;
A power supply unit, a portion of which is provided in the takeoff and landing section and which supplies power to the unmanned aerial vehicle;
The construction machine according to any one of claims 1 to 8 , further comprising: a blocking unit provided on the takeoff and landing section, which blocks noise from the power supply unit.

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