Work machine with emergency stop switch

Abstract

Provided is a work machine capable of undergoing a safe and reliable stop operation implemented by a nearby worker. This work machine comprises a lower traveling body, an upper turning body mounted on the lower traveling body so as to be turnable, and an emergency stop switch (50) attached to the upper turning body. The emergency stop switch (50) has an operation surface (53), and the operation surface (53) faces the outside in the width direction of the upper turning body such that a worker positioned on the side of the work machine can apply a stop operation to an operation part of the operation surface (53) in a posture in which the front-rear direction of the upper turning body and the front-rear direction of the lower traveling body match each other.

Description

Work machines equipped with emergency stop switches

[0001] The present invention relates to a work machine equipped with an emergency stop switch.

[0002] As a conventional work machine capable of performing an emergency stop, a heavy machine equipped with an alarm means is disclosed in Patent Document 1. The heavy machine includes a contact sensor disposed on the rear surface of a rotating part of the heavy machine, and a control unit that stops the power of the heavy machine when a person or object comes into contact with the contact sensor.

[0003] Japanese Patent Application Laid-Open No. 2001-336178

[0004] An object of the present invention is to provide a work machine that can be quickly brought to an emergency stop by an operator located near the work machine.The contact-type sensor described in Patent Document 1 is located on the rear surface of the rotating part of the heavy machine so as to bring the operation of the heavy machine to an emergency stop when a person comes into contact with the heavy machine as it moves backward, and therefore cannot be said to be suitable as a switch that can be intentionally operated by an operator located near the work machine to bring the work machine to an emergency stop.

[0005] The provided work machine includes a lower traveling body, an upper rotating body rotatably mounted on the lower traveling body, and an emergency stop switch attached to the upper rotating body. The emergency stop switch has an operation surface, and an operation unit is provided on the operation surface to apply a stop operation to stop operation of the work machine. The operation surface faces outward in the width direction of the upper rotating body so that an operator positioned to the side of the work machine can apply the emergency stop operation to the operation unit in a reference posture in which the fore-and-aft direction of the upper rotating body, which is the fore-and-aft direction of the upper rotating body, and the fore-and-aft direction of the lower traveling body coincide. The width direction of the upper rotating body is the width direction of the upper rotating body and is a direction on the upper rotating body that is perpendicular to the fore-and-aft direction of the upper rotating body.

[0006] 5A is a diagram showing a hydraulic excavator according to a first embodiment of the present invention.

[0023] FIG. 1 is a perspective view showing an emergency stop switch of the hydraulic excavator.

[0024] FIG. 2 is a diagram showing an electrical circuit including the emergency stop switch, illustrating a normal state in which a stop operation has not been applied to the emergency stop switch.

[0025] FIG. 3 is a diagram showing a circuit including the emergency stop switch, illustrating an emergency state in which the stop operation has been applied to the emergency stop switch.

[0026] FIG. 4 is a perspective view showing a case that houses the emergency stop switch.

[0027] FIG. 5B is a perspective view showing an enlarged view of the portion surrounded by a circle 5B in FIG. 5A.

[0028] FIG. 5C is a side view showing the emergency stop switch and its surrounding parts.

[0029] FIG. 6 is a perspective view showing a routing path of a wire harness connected to the emergency stop switch.

[0030] FIG. 7 is a block diagram showing an emergency stop notification system of the hydraulic excavator.

[0031] FIG. 8 is a flowchart showing the flow of notification control performed by the emergency stop notification system.

[0032] FIG. 9 is a perspective view showing an emergency stop switch and its surrounding parts according to a first modified example of the first embodiment.

[0033] FIG. 10 is a side view showing the portion surrounded by a circle 11B in FIG. 11A. 16A . FIG. 16B is a perspective view showing the mounting position of the emergency stop switch according to the second modified example. FIG. 16C is a perspective view of a hydraulic excavator according to a third modified example of the first embodiment, showing the mounting position of the emergency stop switch. FIG. 16D is a perspective view showing the portion surrounded by circle 13B in FIG. 13A . FIG. 16E is a perspective view of a hydraulic excavator according to a fourth modified example of the first embodiment, showing the mounting position of the emergency stop switch. FIG. 16F is a perspective view showing the portion surrounded by circle 14B in FIG. 14A . FIG. 16G is a plan view showing the maximum turning radius circle of the hydraulic excavator. FIG. 16H is a side view of a hydraulic excavator according to a second modified example of the present invention. FIG. 16I is a perspective view showing the operator's cab of the hydraulic excavator shown in FIG. 16A and a lifting device that lifts and lowers the operator's cab. FIG. 16I is a side view showing the mounting position of the emergency stop switch according to the second modified example. FIG. 16J is a perspective view showing the wiring path of a wire harness connected to the emergency stop switch according to the second modified example. FIG. 16J is a plan view of a work machine according to a first comparative example. FIG. 16J is a plan view of a work machine according to a second comparative example.

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0008] FIG. 1 shows a hydraulic excavator 1 according to a first embodiment of the present invention, and its related elements, a cockpit 30 and a work support server 41. The hydraulic excavator 1 is a work machine for performing excavation work and the like, and includes a crawler-type undercarriage 3, an upper rotating body 10 rotatably mounted on the undercarriage 3, and an attachment. FIG. 1 shows a reference posture of the hydraulic excavator 1, in which the lower traveling body longitudinal direction, which is the fore-and-aft direction of the undercarriage 3, and the upper rotating body longitudinal direction, which is the fore-and-aft direction of the upper rotating body 10, are aligned. FIG. 1 also shows an arrow Up indicating the upward direction of the hydraulic excavator 1, an arrow Dw indicating the downward direction of the hydraulic excavator 1, an arrow Fw indicating the forward direction of the undercarriage 3 and the forward direction of the upper rotating body 10, and an arrow Rr indicating the rearward direction of the undercarriage 3 and the rearward direction of the upper rotating body 10. The same applies to the arrows Up, Dw, Fw, and Rr depicted in figures other than FIG. 1 .

[0009] The upper rotating body 10 includes an upper frame 13, a machine room 11, and an operator's cab (cab) 20, and the machine room 11 and the operator's cab 20 are mounted on the upper frame 13. The attachment is attached to the front end of the upper frame 13 so as to be able to be raised and lowered, and includes a boom 5, an arm 7, and a bucket 9. The machine room 11 houses a power source and a hydraulic pump (not shown). The hydraulic pump is driven by the power source and supplies hydraulic oil to a plurality of hydraulic actuators. The power source may be an engine, or a power source other than an engine, such as an electric motor. The machine room 11 is located at the rear of the upper rotating body 10 in the fore-and-aft direction of the upper rotating body. The operator's cab 20 allows an operator (not shown) to ride in the operator's cab 20 and operate the hydraulic excavator 1. The operator's cab 20 is located at the front of the upper rotating body 10 in the fore-and-aft direction of the upper rotating body and on the left side of the upper rotating body 10 in the width direction of the upper rotating body. The width direction of the upper rotating body is the width direction of the upper rotating body 10 and is a direction perpendicular to the fore-and-aft direction of the upper rotating body in the upper rotating body 10. The operator's cab 20 has a door 21, and the door 21 includes a door opening / closing knob 23 for opening and closing the door 21.

[0010] The hydraulic excavator 1 performs a plurality of operations in response to driving operations by an operator seated in the operator's cab 20. The plurality of operations include a traveling operation of the lower traveling body 3, a swinging operation of the upper rotating body 10, and a raising and lowering operation of the attachment. In this embodiment, the hydraulic excavator 1 is configured to also perform the plurality of operations in response to driving operations by an operator OP in the cockpit 30 located away from the operator's cab 20. In other words, the hydraulic excavator 1 is configured so that it can be remotely controlled in addition to being operated from inside the excavator.

[0011] The cockpit 30 is a remote control device and includes a controller 31, a seat 32, a monitor 33, an operation lever 35, a camera 37, and a wireless communication device 39 shown in FIG. 8. The seat 32 allows an operator OP to sit on the seat 32. The operation lever 35 is operated by the operator OP sitting on the seat 32, and a command signal corresponding to the operation is input to the controller 31. The monitor 33 displays an image of the work site and the like captured by a camera mounted on the hydraulic excavator 1. The camera 37 is positioned so as to capture an image of the face of the operator OP sitting on the seat 32.

[0012] The controller 31, the work support server 41, and the hydraulic excavator 1 are configured to be able to communicate with each other via the wireless communication device 39, a wireless communication device 89 shown in FIG. 8, and the network 40. Specifically, when an operator OP in the cockpit 30 remotely operates the control levers 35 and the like while watching the video of the work site displayed on the monitor 33, commands corresponding to the operations are transmitted to the wireless communication device 89 of the hydraulic excavator 1 via the wireless communication device 39 and the network 40, and thereby the hydraulic excavator 1 performs the plurality of operations in response to the remote operation in exactly the same way as the operation of the operator in the operator cab 20. The work support server 41 includes a database that stores and retains the operation schedule, weather data, etc. of the hydraulic excavator 1, and is configured to support the operation of the hydraulic excavator 1 by the operator OP as necessary.

[0013] The hydraulic excavator 1 further includes an emergency stop switch 50 shown in Figures 2 to 9. In an emergency, a stop operation is given to the emergency stop switch 50 by a nearby worker W who is a worker positioned in the vicinity of the hydraulic excavator 1 as shown in Figure 1, thereby bringing about an emergency stop of the operation of the hydraulic excavator 1. For example, in a remotely operable work machine such as the hydraulic excavator 1, the hydraulic excavator 1 is operated by an operator OP in a cockpit 30 located away from the operator's cab 20. This can lead to situations where the operator OP does not notice obstacles or people in the vicinity of the hydraulic excavator 1, or where the hydraulic excavator 1 becomes uncontrollable due to the operator OP's poor physical condition. In such situations, the nearby worker W gives the stop operation to the emergency stop switch 50.

[0014] The emergency stop switch 50 includes a control box 51 shown in FIG. 2 , a button 55, and a holding mechanism (not shown) housed in the control box 51. The button 55 functions as an operation unit, and the stop operation is applied to the button 55. The control box 51 has a substantially rectangular parallelepiped shape having six outer surfaces. One of the six outer surfaces is an operation surface 53, and the button 55 protrudes from the operation surface 53. The protruding direction of the button 55 is substantially the same as the normal direction of the operation surface 53.

[0015] The emergency stop switch 50 is attached to the upper rotating body 10. The emergency stop switch 50 is connected to equipment of the hydraulic excavator 1 via a wire harness 57 shown in Fig. 7, and the equipment includes a controller 80 shown in Fig. 3A and Fig. 3B.

[0016] The button 55 can be pressed, which is the stop operation, and is configured to forcibly stop the operation of the hydraulic excavator 1. The holding mechanism is, for example, a latching mechanism, and when the button 55 is pressed down to a predetermined pressed position, it holds the button 55 in the pressed position, thereby maintaining the current interruption state and preventing unintended restart of the hydraulic excavator 1. The holding mechanism is a so-called turn-reset type, and is configured so that, after the operator has confirmed safety, they can turn the button 55 in a specified rotational direction, for example, clockwise in Figure 2, thereby releasing the hold on the button 55 and allowing the button 55 to return to its original position.

[0017] 3A and 3B show an electrical circuit including the emergency stop switch 50, which is a circuit for turning on and off the power supply to a lever lock solenoid 83. The lever lock solenoid 83 is included in a lever lock valve formed by an electromagnetic directional control valve, and the lever lock valve is interposed between a pilot hydraulic pressure source and multiple remote control valves included in a hydraulic system (not shown). The lever lock valve is an unloading valve that closes when the lever lock solenoid 83 is energized and interrupts the unloading circuit, thereby allowing pilot primary pressure to be supplied from the pilot hydraulic pressure source to each of the multiple remote control valves, thereby enabling operation of the operating levers included in each of the multiple remote control valves. On the other hand, when the power supply to the lever lock solenoid 83 is interrupted, the lever lock valve opens and opens the unloading circuit, thereby preventing the supply of pilot primary pressure to the multiple remote control valves, thereby disabling operation of the operating levers, i.e., locking the levers. FIG. 3A shows a normal state in which the stop operation has not been applied to the emergency stop switch 50 and the lever lock solenoid 83 is energized, and FIG. 3B shows an emergency state in which the stop operation has been applied to the emergency stop switch 50 and the power supply to the lever lock solenoid 83 has been cut off.

[0018] 3A and 3B , the emergency stop switch 50 is electrically connected to the controller 80. The controller 80 is configured to detect that the button 55 of the emergency stop switch 50 has been pressed, i.e., the stop operation has been performed, and to transmit an alert notification to the cockpit 30.

[0019] The electric circuit further includes an emergency stop relay 81. The emergency stop relay 81 includes a relay coil 81a formed of an electromagnetic coil and a relay contact 81b, the relay coil 81a being interposed between the power supply and the emergency stop switch 50, and the relay contact 81b being interposed between the power supply and the lever lock solenoid 83.

[0020] The emergency stop switch 50 is a normally closed switch, and in a normal state where the button 55 of the emergency stop switch 50 is not pressed, i.e., the stop operation is not applied, the switch contacts included in the emergency stop switch 50 close to allow current to flow through the relay coil 81a, as shown in Fig. 3A. This excites the relay coil 81a, closes the relay contact 81b, and allows current to flow through the lever lock solenoid 83, which closes the lever lock valve including the lever lock solenoid 83 and allows pilot oil to be supplied to each of the multiple remote control valves. In this way, the hydraulic excavator 1 becomes operable as normal.

[0021] 3B , in an emergency state in which the button 55 of the emergency stop switch 50 is pressed, i.e., the stop operation is performed, the switch contact of the emergency stop switch 50 opens, preventing current from flowing to the relay coil 81 a of the emergency stop relay 81. This causes the relay coil 81 a to enter a de-energized state, opening the relay contact 81 b and preventing current from flowing to the lever lock solenoid 83. This opens the lever lock valve including the lever lock solenoid 83, preventing pilot oil from being supplied to each of the multiple remote control valves, i.e., unloading each of the multiple remote control valves and placing them in a hydraulically locked state. In this way, it is impossible to operate the multiple actuators included in the hydraulic excavator 1, such as the attachments and the traveling motors.

[0022] If the wire harness 57 electrically connecting the emergency stop switch 50 and the controller 80, etc., is broken, a state occurs in which no current is supplied from the emergency stop switch 50 to the controller 80, similar to the emergency state shown in Fig. 3B. This causes the controller 80 to determine that the state in which the wire harness 57 is broken is an emergency state, thereby making it possible to achieve a fail-safe.

[0023] The hydraulic excavator 1 further includes a case 60 shown in Fig. 4A. The case 60 houses the emergency stop switch 50 and protects the emergency stop switch 50. The case 60 is made of a strong material such as metal so as to prevent objects such as soil or rubble from directly hitting the emergency stop switch 50 and damaging the emergency stop switch 50, and is attached to the upper rotating body 10 of the hydraulic excavator 1 with the emergency stop switch 50 housed therein. In other words, the emergency stop switch 50 is attached to the hydraulic excavator 1 via the case 60.

[0024] The case 60 shown in FIG. 4A is formed in the shape of a rectangular parallelepiped box, i.e., has a rectangular cylindrical portion and a pair of end portions that close both axial ends of the rectangular cylindrical portion. Specifically, the case 60 includes four side walls 61, 62, 63, and 64 that constitute the rectangular cylindrical portion and a pair of end walls 68 that constitute the end portions. Each of the side walls 61 to 64 has a rectangular shape that is elongated in the axial direction, and each of the pair of end walls 68 has a substantially square shape. Of the side walls 61 to 64, the side wall 61 faces the operation surface 53 of the emergency stop switch 50, and an opening 66 is formed in the side wall 61 and penetrates the side wall 61. The opening 66 is formed at a position corresponding to the operation surface 53, specifically, at a position that allows the button 55 of the emergency stop switch 50 housed in the case 60 to be operated through the opening 66. One of the pair of end walls 68 has a drain hole 67 passing therethrough, allowing rainwater and soil to be discharged from inside the case 60 through the drain hole 67 .

[0025] The case 60 further includes a plurality of magnets 65. In the example shown in FIG. 4A , the plurality of magnets 65 are fixed to the outer surface of the side wall 62, which faces the side wall 61 among the side walls 61 to 64, i.e., the side wall 62 opposite the operation surface 53, and to the outer surface of the side wall 63, which constitutes the bottom wall in the posture shown in FIG. 4A . Each of the magnets 65 is preferably detachably attached to the side walls 62, 63 via fasteners such as bolts. The plurality of magnets 65 are attracted to metal portions of the upper rotating body 10 by magnetic force, thereby enabling the emergency stop switch 50 to be easily attached to the upper rotating body 10 via the case 60 without requiring any special processing of the upper rotating body 10.

[0026] 4B shows a case 70, which is a modified example of the case 60. The case 70 includes four side walls 71, 72, 73, and 74 that form a rectangular cylindrical portion similar to the side walls 61 to 64, and an end wall 78 that closes one of the ends of the rectangular cylindrical portion, but the other end is open to surround an opening 76. Each of the side walls 71 to 74 is rectangular, and the end wall 78 is generally square. The case 70 houses the emergency stop switch 50 so that the operating surface 53 of the emergency stop switch 50 is exposed to the outside of the case 70 through the opening 76, allowing the button 55 of the emergency stop switch 50 to be operated through the opening 76.

[0027] The case 70 further includes a plurality of magnets 75 similar to the plurality of magnets 65, and the plurality of magnets 75 are fixed to the outer surfaces of the four side walls 71, 72, 73, and 74, respectively, and are preferably detachably attached via fasteners such as bolts. Similar to the plurality of magnets 65, the plurality of magnets 75 enable the emergency stop switch 50 to be easily attached to a metal part of the upper rotating body 10 via the case 70 without requiring special processing or the like on the upper rotating body 10.

[0028] Each of the magnets 65, 75 is preferably covered with a relatively soft material such as rubber, which prevents the magnets 65, 75 from directly contacting the upper rotating body 10 and causing scratches or dents on the upper rotating body 10 when the cases 60, 70 are attached to the upper rotating body 10.

[0029] Next, we will explain a preferable arrangement of the emergency stop switch 50. In order to explain the advantages of this arrangement, a first comparative example shown in Fig. 19A and a second comparative example shown in Fig. 19B are prepared.

[0030] 19A and 19B each include a lower traveling body 103, an upper rotating body 110 mounted thereon, and an emergency stop switch 150, similar to the hydraulic excavator 1 according to the above embodiment. In a first comparative example shown in Fig. 19A, the emergency stop switch 150 is attached to the rear surface 112 of the upper rotating body 110, i.e., the surface facing rearward in the fore-and-aft direction of the upper rotating body, with the operation surface of the emergency stop switch 150 facing rearward in the fore-and-aft direction of the upper rotating body. In a second comparative example shown in Fig. 19B, the emergency stop switch 150 is attached to the front surface 114 of the upper rotating body 110, i.e., the surface facing forward in the fore-and-aft direction of the upper rotating body, with the operation surface facing forward in the fore-and-aft direction of the upper rotating body.

[0031] 19A and 19B, the hydraulic excavator 101 spends a longer time in the reference posture, in which the orientation of the upper rotating body 110 and the orientation of the lower traveling body 103 match, than the time when the orientations do not match, i.e., the time when the upper rotating body 110 is in a swing posture in which it swings from the reference posture with respect to the lower traveling body 103. For this reason, situations in which the operator aboard the upper rotating body 110 does not notice obstacles or people present around the hydraulic excavator 101 or the hydraulic excavator 101 becomes uncontrollable are more likely to occur when the hydraulic excavator 101 is moving forward or backward in the reference posture than when the upper rotating body 110 is swinging. When the hydraulic excavator 101 is moving forward or backward in this manner, it is preferable for safety reasons that the peripheral worker W working around the hydraulic excavator 101 is positioned to the side of the hydraulic excavator 101 in the reference posture, i.e., on the outside in the width direction of the upper rotating body 110, as shown in Figures 19A and 19B. Specifically, it is preferable for safety reasons that the peripheral worker W stands in a position more distant from the hydraulic excavator 101 in the width direction of the upper rotating body 110, for example, a position to the side as shown by a circle in Figure 19A, than in a position more distant from the hydraulic excavator 101 in the direction in which the hydraulic excavator 101 moves forward or backward, for example, a position shown by an x ​​in Figure 19A.

[0032] However, as shown in Figures 19A and 19B, the emergency stop switches 150 attached to the center of the rear surface 112 or the front surface 114 of the upper rotating body 110 are both difficult to reach for nearby workers W positioned to the side of the hydraulic excavator 101, and there is a risk that the nearby workers W will not be able to quickly operate the emergency stop switches 150, 160.

[0033] Even if the hand of the peripheral worker W positioned to the side of the hydraulic excavator 101 reaches the emergency stop switch 150, the direction of forward or backward movement of the hydraulic excavator 101 in the reference posture, i.e., the fore-and-aft direction of the upper rotating body, and the direction of the stop operation applied by the peripheral worker W to the emergency stop switch 150 are parallel to each other, which causes a problem that the stop operation itself is difficult. For example, when the hydraulic excavator 101 is moving forward as shown by the white arrow in the second comparative example in FIG. 19B , the direction in which the peripheral worker W applies the stop operation to the emergency stop switch 150, i.e., the direction shown by the black arrow in FIG. 19B , is opposite to the forward movement direction of the hydraulic excavator 101, so the body, for example, the hand, of the peripheral worker W attempting to apply the stop operation to the emergency stop switch 150 may interfere with the hydraulic excavator 101. This problem also occurs when the hydraulic excavator 101 is moving backward in the first comparative example in FIG. 19A . Conversely, when the hydraulic excavator 101 is moving forward in FIG. 19A or when the hydraulic excavator 101 is moving backward in FIG. 19B, the nearby worker W needs to apply a stop operation to the emergency stop switch 150 at a speed that exceeds the speed of the forward movement or rear end of the hydraulic excavator 101.

[0034] In consideration of the above circumstances, the emergency stop switch 50 according to this embodiment is attached to the upper rotating body 10 at a position forward of the operator's cab 20, as shown in Fig. 5A, so that the operation surface 53 faces outward in the width direction of the upper rotating body 10, i.e., in the width direction of the upper rotating body. More specifically, the emergency stop switch 50 is attached to one side in the width direction of the upper rotating body on the front surface 13a of the upper frame 13, as shown in Fig. 5B and Fig. 6, on the left side in the example shown in Fig. 5B, at the end on the side where the operator's cab 20 is located. The upper frame 13 is made of metal, and therefore the emergency stop switch 50 can be easily attached to the upper frame 13 by utilizing the magnet 65 of the case.

[0035] The emergency stop switch 50 and the case 60 that houses it are attached to the upper frame 13 at a position forward of the cab 20. Therefore, even though they are located on the same side as the cab 20 in the width direction of the upper rotating body, they are unlikely to interfere with the body of the driver entering the cab 20, and are therefore unlikely to be an obstacle to the driver attempting to enter the cab 20.

[0036] Furthermore, since the emergency stop switch 50 is attached to the upper rotating body 10 so that the operation surface 53 faces outward in the width direction of the upper rotating body, that is, toward the left in this embodiment, in the reference posture in which the orientation of the upper rotating body 10 and the orientation of the lower traveling body 3 match, the operation surface 53 faces outward (leftward) in the width direction of the entire hydraulic excavator 1. This prevents the direction in which the stop operation is applied to the operation surface 53 of the emergency stop switch 50 by the peripheral worker W, i.e., the stop operation direction, from facing inward in the width direction of the hydraulic excavator 1 in the reference posture, thereby preventing the operation direction from matching the movement direction of the hydraulic excavator 1, i.e., the forward direction or backward direction, and thereby makes it easier for the peripheral worker W to operate the button 55 of the emergency stop switch 50.

[0037] Regarding the position of the emergency stop switch 50 in the width direction of the upper rotating body, as shown in FIG. 5B, the operation surface 53 is located in a position more inward in the width direction of the upper rotating body than the outer surface, i.e., the left side surface 13b, of the upper frame 13, within a range where the nearby worker W located to the side of the hydraulic excavator 1 can operate the emergency stop switch 50, more specifically, at a position closer to the center of the upper rotating body 10 by a distance d1 shown in FIG. 5B than the left side surface 13b.

[0038] In this way, the operating surface 53 of the emergency stop switch 50 is located within a range that can be operated by a nearby worker W located to the side of the hydraulic excavator 1, which enables the nearby worker W to reliably and safely perform the stop operation on the button 55, which is the operating part of the emergency stop switch 50, while being located in a safe area outside the forward and backward paths of the hydraulic excavator 1, in this embodiment, an area to the left of the direction of travel of the hydraulic excavator 1.

[0039] Furthermore, since the surrounding worker W who wishes to bring the operation of the hydraulic excavator 1 to an emergency stop often heads towards the operator's cab 20, in this embodiment the emergency stop switch 50, which is located on the same side as the operator's cab 20 in the width direction of the upper rotating body, i.e., on the left side, can easily be operated to stop the operation by the surrounding worker W approaching the operator's cab 20.

[0040] In addition, since the operating surface 53 of the emergency stop switch 50 is located more inward in the width direction of the upper rotating body than the outer surface of the upper frame 13, in this embodiment the left side surface 13b, the outer surface can function as a protective guard that prevents objects such as rubble from hitting the emergency stop switch or the case 60 that houses it from the outside, thereby suppressing damage to the emergency stop switch 50.

[0041] With regard to the height of the operation surface 53, it is preferable that the upper end of the operation surface 53 be at the same height as or lower than the upper end of the door opening / closing knob 23 of the door 21 of the operator's cab 20. In the example shown in Fig. 6, the position of the emergency stop switch 50 is set so that the upper end of the operation surface 53 is lower by a distance H than the upper end 23a of the door opening / closing knob 23. The door opening / closing knob 23 is usually disposed at a height that allows it to be operated by an operator attempting to get into the operator's cab 20 from the side of the hydraulic excavator 1, and therefore, having the upper end of the operation surface 53 at the same height as or lower than the upper end 23a of the door opening / closing knob 23 allows a nearby worker W positioned to the side of the hydraulic excavator 1 to easily access the operation surface 53.

[0042] 7, the thick solid line and thick dashed line indicate the routing path of the wire harness 57 connected to the emergency stop switch 50. The wire harness 57 includes a switch vicinity portion 57a, an exterior front portion 57b, an exterior interior portion 57c, an exterior lower portion 57d, and an interior portion 57e.

[0043] The switch vicinity portion 57a ​​is inserted into a harness hole (not shown) formed in the case 60 and extends between the inside and outside of the case 60. As shown in Fig. 7, the exterior front portion 57b is routed so as to extend in the width direction of the upper rotating body along the front surface 13a of the upper frame 13. A protective member 58 is attached to the front surface 13a of the upper frame 13, and the protective member 58 has a shape that becomes lower toward the front in the fore-and-aft direction of the upper rotating body so as to cover the exterior front portion 57b of the wire harness 57. The protective member 58 prevents objects such as rubble from coming into contact with the wire harness 57 and causing a break in the wire harness 57.

[0044] The exterior inner portion 57c extends in the front-rear direction of the upper rotating body along the inner surface of the cab 20 in the width direction of the upper rotating body (the left side surface in FIG. 7). The front end of the exterior inner portion 57c is connected to the inner end of the exterior front portion 57b in the width direction of the upper rotating body via a bent portion. The bent portion is a portion where the wire harness 57 is bent approximately 90 degrees. The rear end of the exterior inner portion 57c is connected to the exterior lower portion 57d, which is the area surrounded by a circle 7A in FIG. 7.

[0045] The exterior lower portion 57d is connected to the interior portion 57e through a through-hole formed in the bottom of the cab 20. The interior portion 57e is routed inside the cab 20 and connected to the controller 80 installed in the cab 20. That is, the wire harness 57 is routed so as to electrically connect a plurality of outdoor devices provided outside the cab 20 to the controller 80 inside the cab 20, and the plurality of outdoor devices includes the emergency stop switch 50. In this way, by utilizing the existing through-hole formed in the bottom of the cab 20, the emergency stop switch 50 can be electrically connected to the controller 80 inside the cab 20 without any special processing being performed on the upper rotating body 10.

[0046] The controller 80 can function as a wireless emergency stop device, and is installed behind the driver's seat in the driver's cab 20. The interior portion 57e includes a first interior portion extending rearward from a position near the through-hole on the right side of the driver's seat 25 in the driver's cab 20, a second interior portion extending diagonally upward and left from an end of the first interior portion on the back side of the driver's seat 25, and a third interior portion extending upward from the end of the second interior portion to a position surrounded by a circle 7B in Fig. 7 and connected to the controller 80.

[0047] Next, the emergency stop notification system according to this embodiment will be described.

[0048] With a remotely operated work machine such as the hydraulic excavator 1 according to this embodiment, it is difficult for a nearby worker W to determine whether an operation abnormality has occurred and whether the operator has recognized the abnormality. The operation abnormality determination is a determination as to whether the operation of the hydraulic excavator 1 at the work site is the result of an intentional operation by the operator or whether it is an abnormal operation that is different from the operator's intention. The operator recognition determination is a determination as to whether the operator has noticed an obstacle or a person present around the hydraulic excavator 1. The determination is important for the nearby worker W who is around the remotely operated hydraulic excavator 1 to determine whether to bring the hydraulic excavator 1 to an emergency stop.

[0049] To facilitate such a determination by the nearby worker W, the hydraulic excavator 1 according to this embodiment is equipped with an emergency stop notification system. The emergency stop notification system includes a notification determination unit 80a and a notification device 87 shown in FIG. 8. The notification determination unit 80a functions as a determination unit that determines whether the hydraulic excavator 1 should be brought to an emergency stop, based on information related to operations performed on the controller 31 in the cockpit 30 and information related to the situation around the hydraulic excavator 1. The notification device 87 notifies the nearby worker W of the hydraulic excavator 1 that the emergency stop switch 50 should be operated to stop the hydraulic excavator 1, when the notification determination unit 80a determines that the hydraulic excavator 1 should be brought to an emergency stop.

[0050] 8 is a block diagram showing the emergency stop notification system. The emergency stop notification system includes a plurality of cockpit-side elements provided in the cockpit 30 and a plurality of work machine-side elements provided in the hydraulic excavator 1. The plurality of cockpit-side elements include the controller 31, the wireless communication device 39, the monitor 33, the plurality of control levers 35, and the camera 37, while the plurality of work machine-side elements include the controller 80, the wireless communication device 89, the emergency stop switch 50, the camera 85, and the notification device 87. This emergency stop notification system issues a notification that the emergency stop switch 50 should be operated to stop when predetermined cockpit-side notification conditions or work machine-side notification conditions are satisfied. The cockpit-side notification conditions are conditions related to an abnormality in the cockpit 30, and the work machine-side notification conditions are conditions related to an abnormality in the hydraulic excavator 1, which is the work machine.

[0051] The controller 31 is configured with a microprocessor and includes a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores processing programs, and a RAM (Random Access Memory) that temporarily stores data. The controller 31 is configured to perform a plurality of controls by the CPU, ROM, and RAM working together to execute the processing programs.

[0052] As shown in FIG. 8, the controller 31 includes a distraction determination unit 31a, an operation determination unit 31b, a communication state determination unit 31c, and a notification reason determination unit 31d.

[0053] The looking-away determination unit 31a determines whether or not the operator OP is looking away based on image data of the face of the operator OP captured by the camera 37, generates a determination signal corresponding to the result of the determination, and inputs the generated signal to the wireless communication device 39. Specifically, the looking-away determination unit 31a generates a looking-away signal, which is an abnormal determination signal corresponding to the determination result that the operator OP is looking away, or a not-looking-away signal, which is a normal determination signal corresponding to the determination result that the operator OP is not looking away, and the generated determination signal is transferred from the wireless communication device 39 to the wireless communication device 89 of the hydraulic excavator 1 and input to the controller 80 of the hydraulic excavator 1.

[0054] The operation determination unit 31b determines whether an abnormality exists based on a certain operation time, which is the time during which a certain operation is continuously applied to the operation lever 35. For example, if the operator OP seated in the seat 32 in the cockpit 30 suddenly becomes ill, there is a possibility that the operation lever 35 will remain motionless for a long period of time while being operated in a certain manner. For example, there is a possibility that the operator OP will rotate the operation lever 35 to a predetermined position for a long period of time. In this way, the operation determination unit 31b performs abnormality determination by focusing on the certain operation time, which is the time during which a certain input operation is continuously performed. Specifically, the operation determination unit 31b measures the time during which a certain input operation is continuously applied to the operation lever 35, i.e., the certain operation time, based on an operation signal input from the operation lever 35, determines whether the certain operation time exceeds a predetermined allowable time, and generates a determination signal corresponding to the determination result and inputs it to the wireless communication device 39. Specifically, the operation determination unit 31b generates an abnormal operation signal, which is an abnormal determination signal corresponding to the determination result that the certain operation time exceeds the allowable time, or a normal operation signal, which is a normal determination signal corresponding to the determination result that the certain operation time is equal to or less than the allowable time, and the generated determination signal is transferred from the wireless communication device 39 to the wireless communication device 89 of the hydraulic excavator 1 and input to the controller 80.

[0055] The looking-away signal, the not looking-away signal, the abnormal operation signal, and the normal operation signal each correspond to information relating to an operation in the remote control device.

[0056] The communication state determination unit 31c determines whether or not a communication abnormality has occurred in the wireless communication device 39, generates a determination signal corresponding to the determination result, and inputs the generated signal to the wireless communication device 39. Specifically, the communication state determination unit 31c generates a communication abnormality signal, which is an abnormality determination signal corresponding to the determination result that a communication abnormality has occurred, or a communication normality signal, which is a normality determination signal corresponding to the determination result that no communication abnormality has occurred, and the generated determination signal is transferred from the wireless communication device 39 to the wireless communication device 89 of the hydraulic excavator 1 with support from the ascent operation support server 41, and is input to the controller 80.

[0057] When a notification to the effect that the emergency stop switch 50 should be operated to stop is issued based on an abnormality in the hydraulic excavator 1, which is a work machine, the notification reason determination unit 31d determines the reason for the notification based on information input from the controller 80 of the hydraulic excavator 1, and displays the reason on the monitor 33. This is because the reason for a notification issued based on an abnormality on the work machine side is often unknown to the operator OP operating in the cockpit 30.

[0058] The controller 80 in the hydraulic excavator 1 includes a CPU, a ROM, and a RAM, similar to the controller 31 in the cockpit 30, and is configured to execute a plurality of controls by the CPU, the ROM, and the RAM working together to execute processing programs. Specifically, the controller 80 further includes a surrounding situation determination unit 80b and a communication state determination unit 80c in addition to the notification determination unit 80a.

[0059] The surrounding condition determination unit 80b is configured to detect a detection object, such as an obstacle or a person, in the vicinity of the hydraulic excavator 1 based on image data of the surrounding conditions of the hydraulic excavator 1 captured by the camera 85 installed on the hydraulic excavator 1, specify the relative position of the detected obstacle (for example, a dump truck, a pile of earth or a person) with respect to the hydraulic excavator 1 and its distance from the hydraulic excavator 1, determine whether or not the detection object is present within a predetermined target range around the hydraulic excavator 1 based on the specified relative position and distance, and generate a determination signal corresponding to the determination result and input the determination signal to the alarm determination unit 80a. Specifically, the surrounding condition determination unit 80b is configured to output an object presence signal, which is an abnormality determination signal, when it is determined that the detection object is present within the target range defined around the hydraulic excavator 1, and to output an object absence signal, which is a normal determination signal, when it is determined that the detection object is not present within the target range.

[0060] The target presence signal and the target absence signal correspond to information relating to the situation around the work machine.

[0061] The communication status determination unit 80c determines whether or not a communication abnormality has occurred in the wireless communication device 89, and generates a communication abnormality signal, which is an abnormality determination signal corresponding to the determination result that a communication abnormality has occurred, or a communication normality signal, which is a normality determination signal corresponding to the determination result that no communication abnormality has occurred, and inputs this to the notification determination unit 80a.

[0062] The alarm determination unit 80a is configured to input an alarm start command signal to the alarm device 87 when the abnormality determination signal is input, specifically, when at least one of the averted looking signal generated by the averted looking determination unit 31a, the abnormal operation signal generated by the operation determination unit 31b, the communication abnormality signal generated by the communication state determination unit 31c, the object detection signal generated by the surrounding situation determination unit 80b, and the communication abnormality signal generated by the communication state determination unit 80c is input.

[0063] On the other hand, the alarm determination unit 80a is configured to input an alarm stop command signal to the alarm device 87 when the normal state signal is input after the alarm start command signal is input to the alarm device 87, specifically, when the non-looking away signal is input from the looking away determination unit 31a that generated the looking away signal, when the normal operation signal is input from the operation determination unit 31b that generated the abnormal operation signal, when the normal communication signal is input from the communication state determination unit 31c that generated the communication abnormality signal, when the target absence signal is input from the surrounding situation determination unit 80b that generated the target presence signal, or when the normal communication signal is input from the communication state determination unit 80c that generated the communication abnormality signal. In addition, the notification determination unit 80a is configured to input a notification stop command signal to the notification device 87 even if a pressing operation, i.e., a stop operation, is performed on the button 55 of the emergency stop switch 50 after inputting the notification start command signal to the notification device 87.

[0064] The alarm device 87 includes at least one alarm device installed on the hydraulic excavator 1, such as a speaker, a rotating light, and an electronic signboard capable of displaying letters and images, and is configured, when the alarm start signal is input from the alarm determination unit 80a, to notify a worker W in the vicinity of the hydraulic excavator 1 that the emergency stop switch 50 should be operated to stop, for example, through sound emitted by the speaker, light emitted by the rotating light, and / or letters and images displayed on the electronic signboard. On the other hand, when an alarm stop command signal is input from the alarm determination unit 80a while the alarm device 87 is in a state in which it is issuing an alarm that the emergency stop switch 50 should be operated to stop, the alarm device 87 is configured to stop the alarm through sound, light, and / or letters and images.

[0065] As described above, the notification determination unit 80a of the emergency stop notification system according to this embodiment can accurately determine whether or not to issue a notification to the operator that the hydraulic excavator 1 should be brought to an emergency stop by determining whether or not to bring the hydraulic excavator 1 to an emergency stop based on the status of operation of the controller 31 in the cockpit 30 and the status around the hydraulic excavator 1. For example, the determination of whether or not to issue the notification is accurately made based on whether or not the operator OP in the cockpit 30 is looking away from the driver or continues to unintentionally rotate the operating lever 35, or based on the presence or absence of obstacles or people around the hydraulic excavator 1.

[0066] Furthermore, the notification device 87, in response to a command signal input from the notification determination unit 80a, notifies the worker W in the vicinity of the hydraulic excavator 1 that he or she should operate the emergency stop switch 50 to stop the hydraulic excavator 1, thereby effectively assisting the worker W in determining whether or not to make an emergency stop of the hydraulic excavator 1. In other words, by urging the worker W in the vicinity to operate the emergency stop switch 50 when an emergency stop is necessary, the emergency stop function provided in the hydraulic excavator 1 can be made to function more effectively.

[0067] Next, an example of notification control performed by the emergency stop notification system will be described with reference to the flowchart of FIG.

[0068] The notification determination unit 80a determines whether any abnormal state signal has been input (step S1). If the notification determination unit 80a determines that no abnormal state signal has been input (NO in step S1), specifically, if no abnormal state signal has been input from any of the inattentive behavior determination unit 31a, the operation determination unit 31b, the communication state determination unit 31c, the surrounding situation determination unit 80b, and the communication state determination unit 80c, the notification control is not executed. On the other hand, if it determines that any of the abnormal state signals has been input (YES in step S1), the notification determination unit 80a inputs a notification start command signal to the notification device 87, thereby activating the notification device 87 to notify nearby workers W around the hydraulic excavator 1 that they should operate the emergency stop switch 50 to stop the excavator (step S2).

[0069] If the emergency stop switch 50 is operated to stop the notification after the notification has started (YES in step S3), the notification determination unit 80a inputs a notification stop command signal to the notification device 87 to cause the notification device 87 to stop the notification (step S5). Also, if a normal state signal is input during the notification (YES in step S4), the notification determination unit 80a inputs a notification stop command signal to the notification device 87 to cause the notification device 87 to stop the notification (step S5).

[0070] FIG. 10 is a perspective view showing an emergency stop switch 50 and its mounting structure according to a first modified example of the first embodiment. The hydraulic excavator according to the first modified example includes a support member 59 shown in FIG. 10 in addition to the emergency stop switch 50 and a case 60 that houses the emergency stop switch 50. The support member 59 is mounted to the undercover 26 of the cab 20 while supporting the emergency stop switch 50 and the case 60. Specifically, the support member 59 has a switch support portion 59a and a mounting portion 59b. The mounting portion 59b is a rear end portion in the fore-and-aft direction of the upper rotating body, and is mounted to the undercover 26 by a pair of bolts 26a. The pair of bolts 26a are originally fasteners for fastening the undercover 26 to the cab main body of the cab 20, and the pair of bolts 26a are threadedly engaged with the cab main body while vertically penetrating both the mounting portion 59b and the undercover 26. That is, the support member 59 is attached to the cab 20 by utilizing the bolts 26a for fixing the undercover 26 to the cab main body as support member fasteners. Meanwhile, the emergency stop switch 50 and the case 60 accommodating the emergency stop switch 50 are attached to the switch support portion 59a by a pair of bolts 69, which are switch fasteners, in a state where they are supported on the switch support portion 59a. The pair of bolts 69 are threadedly engaged with the case 60 or the emergency stop switch 50 in a state where they pass through the switch support portion 59a in the vertical direction.

[0071] The use of the support member 59, the support member fastener, and the switch fastener makes it possible to fix the emergency stop switch 50 and the case 60 to the upper rotating body 10 more firmly than the magnet 65. Furthermore, using the pair of bolts 26a for attaching the undercover 26 as the support member fasteners makes it possible to attach the emergency stop switch 50 to the upper rotating body 10 without performing any special processing on the upper rotating body 10.

[0072] Figures 11A, 11B, and 12 show a second modified example of the first embodiment. Figure 11A is a perspective view showing the hydraulic excavator 1 according to the second modified example, and Figures 11B and 12 are a side view and a perspective view, respectively, showing an enlarged view of a portion surrounded by a circle 11B in Figure 11A.

[0073] 11A, that is, a portion of the upper rotating body 10 rearward of the operator's cab 20. Specifically, the emergency stop switch 50 is housed in a case 60, and the case 60 is attached to the bottom 11a of the machine room 11 of the upper rotating body 10, more specifically, to the left side of the bottom 11a in the width direction of the upper rotating body, that is, to the portion closer to the operator's cab 20 in the width direction of the upper rotating body, as shown in FIG.

[0074] In this way, although the emergency stop switch 50 and the case 60 that houses it are located on the same side as the driver's cab 20 in the width direction of the upper rotating body, they are attached to the upper rotating body 10 at a position rearward of the driver's cab 20 in the direction of the upper rotating body, thereby preventing them from interfering with the driver attempting to enter the driver's cab 20.

[0075] The operation surface 53 of the emergency stop switch 50 according to the second modified example is attached at an attachment position shown in Fig. 11B and Fig. 12 while facing outward in the width direction of the upper rotating structure. The attachment position is a position where a nearby worker W positioned on the left side of the hydraulic excavator 1 in the reference posture can apply the stop operation to the emergency stop switch 50, and is closer to the center in the width direction of the upper rotating structure than the left side surface 11b of the machine room 11, more specifically, a position closer to the center by the distance d2 shown in Fig. 12 than the left side surface 11b, that is, a position separated by the distance d2 to the right from the left side surface 11b in the width direction of the upper rotating structure.

[0076] In this way, the operating surface 53 of the emergency stop switch 50 is located more inward in the width direction of the upper rotating body than the left side surface 11b, which is the outer surface of the machine room 11, which enables the left side surface 11b of the machine room 11 to prevent objects such as rubble from hitting the operating surface 53, i.e., to function as a protective guard, i.e., enables the left side surface 11b to prevent damage to the emergency stop switch 50.

[0077] 13A and 13B show a third modified example of the first embodiment. Fig. 13A is a perspective view showing the hydraulic excavator 1 according to the third modified example, and Fig. 13B is a perspective view showing a portion surrounded by a circle 13B in Fig. 13A.

[0078] The emergency stop switch 50 and the case 60 that houses it according to this third modified example are attached to a portion of the upper rotating body 10 that is surrounded by a circle 13B shown in Fig. 13A, i.e., a portion rearward of the operator's cab 20 in the upper rotating body 10. More specifically, as shown in Fig. 13B, the emergency stop switch 50 is attached via the case 60 to a portion of the bottom 11a of the machine room 11 on the side opposite the operator's cab 20 in the width direction of the upper rotating body, that is, on the right side in the upper rotating body 10 illustrated in Figs. 13A and 13B.

[0079] In this way, the area on the opposite side of the operator's cab 20 in the width direction of the upper rotating structure and rearward of the operator's cab 20 is an area that is likely to be a blind spot for the operator inside the operator's cab 20, and therefore it is possible to more effectively exercise the function of the emergency stop switch 50. In other words, a stop operation can be quickly given to the emergency stop switch 50 according to the third modified example by a nearby worker W positioned on the opposite side (right side) of the operator's cab 20 in the width direction of the upper rotating structure.

[0080] <Orientation of operation surface> In this third modified example, as shown in FIG. 13B , the operation surface 53 of the emergency stop switch 50 faces outward in the width direction of the upper rotating body and is located at a position closer to the center in the width direction of the upper rotating body than the right side surface 11 c of the machine room 11, within a range that allows a nearby worker W located on the opposite side (right side) of the hydraulic excavator 1 from the operator's cab 20 to operate the emergency stop switch 50 to stop the operation, that is, at a position away from the right side surface 11 c to the left in the width direction of the upper rotating body.

[0081] In this way, the operating surface 53 of the emergency stop switch 50 is located more inward in the width direction of the upper rotating body than the right side surface 11c, which is the outer surface of the machine room 11, which enables the right side surface 11c of the machine room 11 to prevent objects such as rubble from hitting the operating surface 53, i.e., to function as a protective guard, i.e., enables the left side surface 11b to prevent damage to the emergency stop switch 50.

[0082] 14A and 14B show a fourth modified example of the first embodiment. Fig. 14A is a perspective view of the hydraulic excavator 1 according to the fourth modified example, and Fig. 14B is a perspective view showing a portion surrounded by a circle 14B in Fig. 14A.

[0083] The hydraulic excavator 1 according to the fourth modified example includes two emergency stop switches 50A, 50B and cases 60, 70 that house the switches, respectively. The emergency stop switches 50A, 50B and the cases 60, 70 are attached to the portion of the upper rotating body 10 that is surrounded by the circle 14B shown in Fig. 14A, i.e., the front end portion on the right side in the width direction of the upper rotating body. The emergency stop switch 50A and the case 70 that houses the switch are attached to the front surface 19a of the upper frame 19 that supports the trunk room 17 of the upper rotating body 10, as shown in Fig. 14B. More specifically, the case 70 that houses the emergency stop switch 50A includes a plurality of magnets 75, similar to the case 70 shown in Fig. 4B, and the plurality of magnets 75 are fixed to the upper frame 19 by magnetic force. The case 60 that houses the emergency stop switch 50B includes a plurality of magnets 65, similar to the case 60 shown in FIG. 4A, and the plurality of magnets 65 are fixed to the right side surface 19b of the upper frame 19 by magnetic force.

[0084] 14B , in the fourth modified example, the operation surfaces 53A, 53B of the emergency stop switches 50A, 50B both face outward in the width direction of the upper rotating structure and are disposed in positions where a nearby worker W located on the right side of the hydraulic excavator 1 can apply a stop operation to the emergency stop switches 50A, 50B. Specifically, the operation surface 53A of the emergency stop switch 50A is disposed in a position closer to the center of the upper rotating structure 10 in the width direction of the upper rotating structure than the right side surface 19b of the upper frame 19, i.e., to the left of the right side surface 19b in the width direction of the upper rotating structure, within a range where a nearby worker W located on the right side of the hydraulic excavator 1 can apply the stop operation to the emergency stop switch 50A. In contrast, the operation surface 53 of the emergency stop switch 50B is disposed in a position where it protrudes outward, i.e., to the right, in the width direction of the upper rotating structure than the right side surface 19b of the upper frame 19. The case 60 that houses the emergency stop switch 50B can prevent objects such as rubble from hitting the operation surface 53B arranged in this manner.

[0085] Even in the case where it is difficult to bring the operation surface 53B close to the center of the upper rotating body 10 in the width direction of the upper rotating body as in the case of the emergency stop switch 50B according to the fourth modification, it is preferable that the emergency stop switch 50B, or more preferably, the case 60 that houses the emergency stop switch 50B, fits inside a maximum turning radius circle CR as shown in Fig. 15. The maximum turning radius circle CR is a circle whose center is the center of rotation of the upper rotating body 10 and has a radius equal to the maximum turning radius of the upper rotating body 10, and the maximum turning radius is the distance in a plan view between the center of rotation and a part of the upper rotating body 10 that does not include a working device such as the attachment.

[0086] If the emergency stop switch 50 deviates outside the maximum turning radius circle CR, the turning radius of the emergency stop switch 50 exceeds the maximum turning radius of the upper rotating body 10, increasing the possibility that the emergency stop switch 50 will come into contact with an obstacle or a person as the upper rotating body 10 turns. This forces the operator to work more carefully to avoid the contact, which may result in a deterioration in workability.

[0087] In contrast, locating the emergency stop switch within the maximum turning radius circle CR makes it possible to provide the work machine with an emergency stop function without increasing the workload of the operator.

[0088] Furthermore, the operation surfaces 53A, 53B of the emergency stop switches 50A, 50B in this fourth modified example are both located in positions where a nearby worker W located on the right side of the hydraulic excavator 1, i.e., on the opposite side from the cab 20, can apply a stop operation to the emergency stop switches 50A, 50B, in other words, positions where a pressing operation can be applied to the buttons 55A, 55B of the emergency stop switches 50A, 50B. Therefore, a nearby worker W who is in an area that is likely to be a blind spot for the operator because it is on the opposite side of the cab 20, i.e., the area to the right of the hydraulic excavator 1, can reliably and quickly operate the emergency stop switches 50A, 50B.

[0089] Next, a second embodiment of the present invention will be described with reference to FIGS. 16A, 16B and 17. FIG.

[0090] Figure 16A shows a hydraulic excavator 201 according to the second embodiment. The hydraulic excavator 201 includes a lower traveling body 203, an upper rotating body 210 rotatably mounted on the lower traveling body 203, and an attachment including a boom 205. The upper rotating body 210 includes a machine room 211, a cab 220, and an elevator device 90 that raises and lowers the cab 220. The cab 220 is provided in front of the upper rotating body 210 in the fore-and-aft direction of the upper rotating body and on the left side in the width direction of the upper rotating body. The elevator device 90 is configured to raise and lower the cab 220 between a lower position shown in Figure 16A and an upper position shown in Figure 16B.

[0091] As shown in FIGS. 16B and 17 , the lifting device 90 includes a base 91, a pair of link members 92, a cylinder 94, and an emergency lowering valve 93. The base 91 is erected on the upper frame of the upper rotating body 210 at a position forward of the machine room 211 shown in FIG. 16A . The pair of link members 92 are arranged to interconnect the operator's cab 220 and the base 91, and constitute a parallel link mechanism in cooperation with the operator's cab 220 and the base 91. Each of the pair of link members 92 has opposite ends that are rotatably connected to the operator's cab 120 and the base 91, respectively. The parallel link mechanism enables the operator's cab 120 to move in parallel between the lower position in front of the base 91 as shown in FIG. 16A and the upper position as shown in FIG. 16B while maintaining a horizontal posture. The cylinder 94 has opposite ends, which are rotatably connected to the operator's cab 120 and the base 91, respectively. The cylinder 94 is made of, for example, a hydraulic cylinder capable of telescopic movement, and is arranged so as to raise and lower the operator's cab 120 between the lower position and the upper position by the telescopic movement. The emergency lowering valve 93 is a valve that is operated in an emergency to reduce the pressure in the cylinder 94 and lower the operator's cab 120 to the lower position, and is arranged at a position where it can be operated by a worker W in the vicinity of the hydraulic excavator 101, specifically, on the outer (left) surface of the base 91 in the width direction of the upper rotating body.

[0092] FIG. 17 is a side view showing the mounting positions of the emergency stop switch 250 and the case 260 that houses the switch according to the second embodiment. The emergency stop switch 250 is mounted on a portion of the upper rotating body 210 rearward of the operator's cab 220, which is in the lower position, and which does not move up or down regardless of the operation of the lifting device 90. More specifically, as shown in FIG. 17 , the case 260 that houses the emergency stop switch 250 is mounted via a support member 259 on the outer (left) surface of the base 91 at a position below the emergency lowering valve 93. That is, the emergency stop switch 250 is mounted via the case 260 and the support member 259 to the base 91, which is a portion of the lifting device 90 that does not move up or down. This allows a nearby worker W on the ground positioned to the side of the hydraulic excavator 201 (on the left side in the illustrated example) to easily apply a stop operation to the emergency stop switch 250 regardless of the lifting or lowering of the operator's cab 220.

[0093] Furthermore, since the emergency stop switch 250 is located near the emergency lowering valve 93, even if the operation of the hydraulic excavator 201 is stopped by operating the emergency stop switch 250 while the operator's cab 220 is raised from the lower position, the operator's cab 220 can be quickly lowered by operating the emergency lowering valve 93 immediately thereafter.

[0094] In this second embodiment, too, the emergency stop switch 250 is positioned so that the operating surface 253 faces outward in the width direction of the upper rotating body, in other words, so that it faces outward (left side) in the width direction of the hydraulic excavator 201 in the reference posture in which the fore-and-aft direction of the upper rotating body of the upper rotating body 210 and the fore-and-aft direction of the lower running body of the lower running body 203 coincide.

[0095] 17, the upper end of the operation surface 253 is at the same height as or lower than the upper end 224 of the door opening / closing knob 223 of the door 221 of the operator's cab 220 in the lower position. This makes it possible for a peripheral worker W on the ground who is positioned to the side of the hydraulic excavator 201 on the same side as the door 221 (the left side in the illustrated example) regardless of whether the operator's cab 220 is raised, to easily apply a stop operation to the operation surface 253.

[0096] 18 shows, with a thick solid line and a thick dashed line, the routing path of a wire harness 257 connected to the emergency stop switch 250 according to the second embodiment. The wire harness 257 is inserted through a harness hole formed in the case 260 and routed inside and outside the case 260. As shown in FIG. 18 , the wire harness 257 extends in the width direction of the upper rotating structure along the back surface 91 a of the base 91 between the base 91 and the machine room 211, which are aligned in the fore-and-aft direction of the upper rotating structure. The wire harness 257 includes a portion 257 a extending in the width direction of the upper rotating structure from the case 260 to a position inward in the width direction of the upper rotating structure (to the right in FIG. 18 ), and a portion 257 b extending along the back surface 91 a of the base 91 from the inner end of the portion 257 a to the top end of the base 91.

[0097] On the other hand, as shown in Figure 18, a hydraulic hose 95 connected to the cylinder 94 and another wire harness 97 other than the wire harness 157 are arranged in the vertical direction along the back surface 91a of the base 91 while being aligned with each other in the width direction of the upper rotating body, and the wire harness 257 connected to the emergency stop switch 250 is arranged so as to merge with the other wire harness 97 at the upper end of the base 91.

[0098] The other wire harness 97 is routed so as to electrically connect a controller installed in the cab 220 with equipment provided outside the cab 220, and a through-hole is formed in the bottom of the cab 220 to allow the other wire harness 97 to pass through so as to enable the other wire harness 97 to be routed from the inside to the outside of the cab 220. The wire harness 257 connected to the emergency stop switch 250 is routed from the inside to the outside of the cab 220 together with the other wire harness 97 through the through-hole. In this way, using the through-hole formed in the bottom of the cab 220 makes it possible to electrically connect the emergency stop switch 250 with a controller in the cab 220 without performing any special processing on the upper rotating body 210.

[0099] The present invention is not limited to the above-described embodiment, but can be modified in various ways, for example, as described below.

[0100] The work machine according to the present invention is not limited to the above-described hydraulic excavator 1, 201. The work machine according to the present invention may be a work machine other than a hydraulic excavator, for example, a self-propelled work machine such as a crawler crane.

[0101] The undercarriage according to the present invention is not limited to the undercarriage 3, 203 having a pair of crawlers, but may be, for example, an undercarriage having a plurality of wheels.

[0102] The upper rotating body of the present invention is not limited to the above-mentioned upper rotating body 10, 210 in which the operator's cab 20, 220 is located on the left side in the width direction of the upper rotating body, but may also be, for example, one in which the operator's cab is located on the right side in the width direction of the upper rotating body.

[0103] The working machine according to the present invention is not limited to one that can be remotely controlled, but may be a working machine that is operated solely based on the driving operations of an operator seated in the operator's cab 20, 220, for example.

[0104] The emergency stop notification system is optional and not necessarily required.

[0105] As such, the above-described embodiment is merely illustrative and is not intended to limit the present invention. Furthermore, all modifications and variations within the scope of the claims are within the scope of the present invention.

[0106] As described above, a work machine is provided that can be quickly brought to an emergency stop by an operator located near the work machine. The work machine includes a lower traveling body, an upper rotating body rotatably mounted on the lower traveling body, and an emergency stop switch attached to the upper rotating body. The emergency stop switch has an operation surface, and an operation unit is provided on the operation surface through which a stop operation to stop operation of the work machine is applied. The operation surface faces outward in the width direction of the upper rotating body so that an operator located to the side of the work machine can apply the emergency stop operation to the operation unit in a reference attitude in which the fore-and-aft direction of the upper rotating body, which is the fore-and-aft direction of the upper rotating body, and the fore-and-aft direction of the lower traveling body coincide. The width direction of the upper rotating body is the width direction of the upper rotating body and is a direction perpendicular to the fore-and-aft direction of the upper rotating body on the upper rotating body.

[0107] By facing outward in the width direction of the upper rotating body, the operation surface including the operation unit of the emergency stop switch allows a nearby worker positioned to the side of the work machine in a standard attitude in which the fore-and-aft directions of the upper rotating body and the lower traveling body coincide, i.e., a nearby worker positioned in a safe area off the path of the lower traveling body, to apply the stop operation to the operation unit, thereby enabling the nearby worker to safely and quickly bring the operation of the work machine to an emergency stop. Furthermore, because the direction in which the stop operation is applied to the operation unit by the nearby worker, i.e., the width direction of the upper rotating body or a direction close thereto, is significantly different from the direction of travel of the work machine, i.e., the travel direction of the lower traveling body, it is possible to effectively prevent interference between the hand or the like of a nearby worker attempting to apply the stop operation to the emergency stop switch and the work machine.

[0108] When the upper rotating body includes a cab and allows an operator to board the cab and operate the work machine, it is preferable that the emergency stop switch be positioned in front of or behind the cab in the fore-and-aft direction of the upper rotating body, and that the operating surface be positioned closer to the center of the upper rotating body in the width direction of the upper rotating body than the side of the upper rotating body around the emergency stop switch, within a range that allows a nearby worker positioned to the side of the work machine in the standard posture to perform the stop operation on the emergency stop switch.

[0109] Since positions in front of or behind the cab are likely to be blind spots for the operator in the cab, the emergency stop switch installed in such a position enables nearby workers who are in a position that is likely to be in the operator's blind spot to properly and quickly perform the stop operation on the emergency stop switch.

[0110] Furthermore, by positioning the operating surface closer to the center of the upper rotating body in the width direction of the upper rotating body than the side of the upper rotating body surrounding the emergency stop switch, within the range where the nearby worker can perform the stop operation on the emergency stop switch, the side of the upper rotating body can function as a protective guard that prevents objects such as rubble from hitting the operating surface, thereby making it possible to prevent damage to the emergency stop switch.

[0111] If the driver's cab includes a door that can be opened and closed, and the door includes a door opening / closing knob that is operated to open and close the door, it is preferable that the operating surface be positioned so that the upper end of the operating surface is at the same height as the upper end of the door opening / closing knob or lower than the upper end of the door opening / closing knob.

[0112] Since the door opening / closing knob is the part that is operated by the operator to open and close the door of the driver's cab, the fact that the upper end of the operating surface is at the same height as or lower than the upper end of the door opening / closing knob makes it possible for a nearby worker positioned to the side of the work machine to easily perform a stop operation on the operating part of the operating surface.

[0113] It is preferable that the operator's cab be located on either the left or right side in the width direction of the upper rotating body, with the operation surface facing the one side. This allows a nearby worker approaching the work machine from the one side of the operator's cab to easily and quickly operate the emergency stop switch to stop the work machine. Moreover, because the emergency stop switch is located forward or rearward of the operator's cab, it is possible to prevent the emergency stop switch from interfering with the operator attempting to enter the operator's cab.

[0114] The operator's cab may be configured to be able to rise and fall between a lower position and an upper position higher than the lower position. In this case, the emergency stop switch is preferably attached to a portion of the upper rotating body that is forward or rearward in the fore-and-aft direction of the upper rotating body from the operator's cab in the lower position and that does not rise and fall. This allows a worker on the ground in the vicinity to easily apply the stop operation to the emergency stop switch regardless of whether the operator's cab is raised.

[0115] In this case, it is preferable that the upper end of the operation surface is at the same height as the upper end of the door knob of the driver's cab when it is in the lower position or at a position lower than the door knob when it is in the lower position, which enables a worker on the ground nearby to easily apply a stop operation to the operation surface of the emergency stop switch regardless of whether the driver's cab is raised or lowered.

[0116] The emergency stop switch is preferably attached to the upper rotating body at a position within a maximum turning radius circle of the upper rotating body. The maximum turning radius circle is a circle centered on the center of rotation of the upper rotating body and having a radius equal to the maximum turning radius of the upper rotating body, which is the distance in a plan view between the center of rotation and the farthest point from the center of rotation of the upper rotating body, excluding the attachment. Arranging the emergency stop switch within such a maximum turning radius circle makes it possible to prevent the emergency stop switch from coming into contact with objects around the work machine as the upper rotating body rotates, regardless of whether the emergency stop switch is located inside or outside the outer surface of the upper rotating body in the direction of the turning radius, and thereby makes it possible to suppress an increase in the burden on the operator caused by preventing damage to the emergency stop switch.

[0117] The work machine may be configured to be remotely controlled by operating a remote control device located away from the driver's cab. In this case, it is preferable that the work machine further include a determination unit that determines whether or not an emergency stop should be made on the work machine based on information related to the operation of the remote control device and information related to the situation around the work machine, and a notification device that, when the determination unit determines that an emergency stop should be made on the work machine, notifies nearby workers around the work machine that they should apply the stop operation to the emergency stop switch. The notification enables the nearby workers to easily determine whether or not the stop operation should be applied to the emergency stop switch.

Claims

1. A work machine comprising: a lower running body; an upper rotating body rotatably mounted on the lower running body; and an emergency stop switch attached to the upper rotating body, wherein the emergency stop switch has an operating surface and an operating unit is provided on the operating surface to which a stop operation for stopping operation of the work machine is applied, the operating surface faces outward in the width direction of the upper rotating body so that an operator positioned to the side of the work machine can apply the stop operation to the operating unit in a reference posture in which the fore-and-aft direction of the upper rotating body, which is the fore-and-aft direction of the upper rotating body, and the fore-and-aft direction of the lower running body coincide, and the width direction of the upper rotating body is the width direction of the upper rotating body and is a direction perpendicular to the fore-and-aft direction of the upper rotating body on the upper rotating body.

2. A work machine as described in claim 1, wherein the upper rotating body includes a driver's cab that allows an operator to board the cab and operate the work machine, the emergency stop switch is located in a position forward or rearward of the driver's cab in the fore-and-aft direction of the upper rotating body, and the operating surface is located in a position closer to the center of the upper rotating body in the width direction of the upper rotating body than the side of the upper rotating body around the emergency stop switch, within a range that allows an operator positioned to the side of the work machine in the reference posture to perform the stop operation on the emergency stop switch.

3. A work machine as described in claim 2, wherein the operator's cab includes an openable and closable door, the door includes a door opening / closing knob that is operated to open and close the door, and the upper end of the operating surface is at a position equal to the height of the upper end of the door opening / closing knob or at a position lower than the upper end of the door opening / closing knob.

4. A work machine as set forth in claim 2 or 3, wherein the operator's cab is disposed on either the left or right side in the width direction of the upper rotating body, and the operating surface faces the one side.

5. A work machine as described in claim 1, wherein the upper rotating body includes a driver's cab that allows an operator to board the cab and operate the work machine, the driver's cab is configured to be able to rise and fall between a lower position and an upper position that is higher than the lower position, and the emergency stop switch is attached to a location that is forward or rearward of the driver's cab in the lower position in the fore-and-aft direction of the upper rotating body and that does not rise or fall.

6. A work machine as claimed in claim 5, wherein the upper end of the operating surface is at a position equal to the height of the upper end of the door opening / closing knob of the door of the driver's cab when the door is in the lower position, or at a position lower than the upper end of said door opening / closing knob.

7. A work machine as set forth in any one of claims 1 to 6, wherein the emergency stop switch is disposed within the maximum turning radius circle of the upper rotating body, and the maximum turning radius circle is a circle having a center on the center of rotation of the upper rotating body and a radius equal to the maximum turning radius of the upper rotating body.

8. A work machine as claimed in claim 1, wherein the upper rotating body includes a cab in which an operator sits, and the work machine is configured so as to be capable of being remotely operated by operation of a remote control device located away from the cab, and the work machine further comprises a determination unit which determines whether the work machine should be brought to an emergency stop based on information relating to the operation of the remote control device and information relating to the situation around the work machine, and an alarm device which, when the determination unit determines that the work machine should be brought to an emergency stop, notifies a worker in the vicinity of the work machine that the stop operation should be applied to the emergency stop switch.

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