Construction machine

Abstract

To protect a wiper moving mechanism by a protective member against earth and sand flying toward the wiper moving mechanism.SOLUTION: A hydraulic excavator 1 includes: a cab 7 provided with front windshield glass 7F; and a wiper device 9 for wiping dirt off the front windshield glass 7F. The wiper device 9 is configured to include: a wiper blade 10 moving in contact with the front windshield glass 7F; and a wiper moving mechanism 13 transmitting power from an electric actuator 11 to the wiper blade 10. A protective member 14 covering the periphery of the wiper moving mechanism 13 is provided on a front end side of a revolving frame 5. The protective member 14 is disposed below the wiper moving mechanism 13 and includes: a lower plate 15 covering the wiper moving mechanism 13 from below; and a front fence 16 extending upward from a front side of the lower plate 15 and covering the wiper moving mechanism 13 from the front.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to construction machinery such as a hydraulic excavator equipped with a cab and a wiper device.

Background Art

[0002] A hydraulic excavator, which is representative of construction machinery, includes a self-propelled lower traveling body, an upper revolving body rotatably mounted on the lower traveling body, and a working device provided on the front side of the upper revolving body so as to be capable of pitching. A cab forming a driver's cab is provided on the front side of the upper revolving body.

[0003] The cab generally has a box shape surrounded by a front surface, a rear surface, a left side surface, a right side surface, and an upper surface, and covers a driver's seat, various operating devices, and the like. Windows are provided on the front surface, the rear surface, the left side surface, the right side surface, and the upper surface of the cab, and transparent plates (window glasses) formed of tempered glass or the like are attached to these windows. An operator sitting on the driver's seat operates the operating device while visually observing the surroundings of the hydraulic excavator through the window glass attached to the window of the cab, and performs earth and sand excavation work or the like with the working device.

[0004] A wiper device for wiping dirt, water droplets, etc. on the front window glass attached to the front window is provided in the cab. The wiper device includes a wiper blade that moves in contact with the front window glass and a wiper movable mechanism that transmits power from a power source to the wiper blade. The wiper movable mechanism is often arranged at the peripheral edge of the front window.

[0005] On the other hand, a hydraulic excavator has been proposed in which a wiper movable mechanism is arranged on the front side of a revolving frame on which a cab is mounted (Patent Document 1). This hydraulic excavator can ensure a larger field of view for the operator without the field of view of the operator being blocked by the wiper movable mechanism as compared with a configuration in which the wiper movable mechanism is arranged at the peripheral edge of the front window.

Prior Art Documents

Patent Documents

[0006] Patent Document 1 Japanese Patent No. 4883626 Summary of the Invention Problems to be Solved by the Invention

[0007] However, in the hydraulic excavator according to Patent Document 1, the power source (motor) is arranged inside a cover member provided on the front side of the swing frame, and the wiper movable mechanism (wiper shaft and wiper movable part) for transmitting the power of the motor to the wiper blade is exposed outside the cover member. When the hydraulic excavator travels on a rough road such as a work site, the earth and sand scattered and bounced up by the crawler of the lower traveling body fly toward the wiper device and the like. For this reason, there is a problem that the wiper device is damaged when the earth and sand flying toward the wiper device and the like collide with the wiper movable mechanism.

[0008] The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a construction machine capable of protecting a wiper movable mechanism. Means for Solving the Problems

[0009] The present invention includes a self-propelled vehicle body, a cab disposed on the front side of the vehicle body and provided with a transparent front plate, and a wiper device for wiping dirt on the transparent front plate. The wiper device includes a wiper blade that moves in contact with the transparent front plate, and a wiper movable mechanism that is attached to the vehicle body and transmits power from a power source to the wiper blade. In the construction machine configured to include the above, a protective member that covers the periphery of the wiper movable mechanism is provided on the front end side of the vehicle body, and the protective member has a lower protective portion that is disposed below the wiper movable mechanism and covers the wiper movable mechanism from below. Effects of the Invention

[0010] According to the present invention, the wiper movable mechanism can be protected by a protective member against earth and sand flying toward the wiper movable mechanism.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 7, taking a hydraulic excavator as an example.

[0013] A hydraulic excavator 1 representing construction machinery includes a self-propelled lower traveling body 2 and an upper revolving body 3 rotatably mounted on the lower traveling body 2, and the vehicle body is constituted by the lower traveling body 2 and the upper revolving body 3. The lower traveling body 2 has left and right crawlers (tracks) 2A and can stably travel on an unprepared work site. The upper revolving body 3 includes a revolving frame 5, a counterweight 6, a cab 7, a lower front cover 8, etc., which will be described later. A working device 4 is rotatably provided on the front side of the upper revolving body 3, and earth and sand excavation work, etc. is performed using the working device 4.

[0014] The slewing frame 5 constitutes the base of the upper slewing body 3 and is mounted on the lower traveling body 2 via a slewing device so as to be slewing - capable. The slewing frame 5 has a bottom plate (not shown), a left - side frame 5A arranged on the left side of the bottom plate and extending in the front - rear direction, a right - side frame 5B arranged on the right side of the bottom plate and extending in the front - rear direction, and left and right vertical plates (not shown) erected on the bottom plate and extending in the front - rear direction. At the front end of the left - side frame 5A, a front - side cab support frame 5C extending in the left - right direction is provided. At the front side of the left and right vertical plates, the proximal end of the working device 4 is rotatably attached. At the rear side of the left and right vertical plates, a counterweight 6 is provided, and the counterweight 6 maintains the weight balance with the working device 4. The front - side cab support frame 5C supports the front - side part of the cab 7 described later, and a cab lower front cover 8 and a wiper device 9 described later are attached to the front surface of the front - side cab support frame 5C.

[0015] The cab 7 is arranged at the left - front part of the slewing frame 5. The cab 7 forms a driver's cab, and a driver's seat, a travel lever - pedal device, an operation lever device, etc. (all not shown) are provided in the cab 7. The cab 7 is formed in a box - shape surrounded by a front surface 7A, a rear surface 7B, a left - side surface 7C, a right - side surface 7D, and an upper surface 7E. A front window (opening) is formed almost over the entire area of the front surface 7A of the cab 7, and a front - window glass 7F as a transparent front plate formed using tempered glass or the like is attached to this front window.

[0016] On the left - side surface 7C of the cab 7, a door 7G for getting on and off and a left - window glass 7H attached to the left window are provided. Rear - window glass and right - window glass (both not shown) are also provided on the rear surface 7B and the right - side surface 7D of the cab 7, respectively. The operator who gets into the cab 7 operates the operation lever device etc. while visually observing the surroundings of the hydraulic excavator 1 through the front - window glass 7F, the left - window glass 7H, the right - window glass, and the rear - window glass etc., and drives the working device 4 to perform earth - sand excavation work etc.

[0017] The lower front cover 8 of the cab is attached to the front surface of the front cab support frame 5C that constitutes the swing frame 5. The lower front cover 8 of the cab is supported by the front cab support frame 5C via a bracket or the like (not shown) and extends in the left - right direction in a state of protruding forward from the front cab support frame 5C. The left side of the lower front cover 8 is a narrow - width portion 8A with a small amount of protrusion from the front cab support frame 5C, and the right side of the lower front cover 8 is a wide - width portion 8B with a large amount of protrusion from the front cab support frame 5C. A trapezoidal opening 8C is formed in the narrow - width portion 8A of the lower front cover 8, and the output shaft 11A of an electric actuator 11 described later is inserted through this opening 8C.

[0018] The wiper device 9 is provided between the front cab support frame 5C of the swing frame 5 and the front surface 7A of the cab 7. The wiper device 9 ensures the visibility of an operator who operates the working device 4 etc. inside the cab 7 by wiping off dirt, water droplets etc. adhering to the front window glass 7F. As shown in FIGS. 2 and 4, the wiper device 9 includes a wiper blade 10 that abuts against the front window glass 7F and moves in the left - right direction, an electric actuator 11 as a power source for driving the wiper blade 10, and a wiper movable mechanism 13 that transmits the power from the electric actuator 11 to the wiper blade 10.

[0019] The wiper blade 10 is composed of a blade holding member 10A, an upper blade 10B and a lower blade 10C held by the blade holding member 10A. The upper blade 10B and the lower blade 10C are formed in an elongated plate shape from a rubber material and are held in a posture (vertical posture) extending linearly in the up - down direction by the blade holding member 10A. When the parallel link 13A described later swings in the left - right direction, the blade holding member 10A moves in the left - right direction while maintaining the vertical posture. Thereby, the upper blade 10B and the lower blade 10C move in the left - right direction in a state of abutting against the front window glass 7F, and wipe off dirt, water droplets etc. adhering to the front window glass 7F.

[0020] The electric actuator 11 is provided within the narrow portion 8A of the lower front cover 8 of the cab. The electric actuator 11 is configured to include, for example, an electric motor, a reduction mechanism (both not shown), etc. The electric actuator 11 is attached, for example, to the upper surface 12A side of a bracket 12 provided on the slewing frame 5, and is disposed between the front cab support frame 5C of the slewing frame 5 and the lower front cover 8 (narrow portion 8A). The output shaft 11A of the electric actuator 11 protrudes forward through the opening 8C of the lower front cover 8, and is connected to the actuator-side connecting portion 13B of a wiper movable mechanism 13, which will be described later, outside the lower front cover 8. The electric actuator 11 is covered by the lower front cover 8, and thus is protected from, for example, earth and sand splashed up by the crawler 2A during the travel of the hydraulic excavator 1, or earth and sand dropped from the working device 4 during the excavation work.

[0021] The wiper movable mechanism 13 connects between the output shaft 11A of the electric actuator 11 and the blade holding member 10A of the wiper blade 10. The wiper movable mechanism 13 is configured to include a parallel link 13A, an actuator-side connecting portion 13B, and a blade-side connecting portion 13C. The parallel link 13A has a narrow first link 13A1 and a wide second link 13A2 that are paired in the left-right direction. The actuator-side connecting portion 13B has a first connecting portion 13B1 that connects between the lower end of the first link 13A1 and the output shaft 11A of the electric actuator 11, and a second connecting portion 13B2 that rotatably connects the lower end of the second link 13A2 to the lower front cover 8. The blade-side connecting portion 13C connects between the upper end sides of the first link 13A1 and the second link 13A2 that constitute the parallel link 13A and the blade holding member 10A of the wiper blade 10.

[0022] When the electric actuator 11 is driven, the power (rotational force) of the output shaft 11A is transmitted to the first connecting portion 13B1 of the actuator side connecting portion 13B that constitutes the wiper movable mechanism 13. The first link 13A1 and the second link 13A2 that constitute the parallel link 13A swing in the left - right direction around the output shaft 11A of the electric actuator 11, and move the blade holding member 10A of the wiper blade 10 connected to the blade side connecting portion 13C in the left - right direction while maintaining a vertical posture. In this way, the upper blade 10B and the lower blade 10C held by the blade holding member 10A wipe off dirt, water droplets, etc. adhering to the front window glass 7F.

[0023] Next, the protective member 14 used in this embodiment will be described.

[0024] The protective member 14 is provided on the front - end side of the swivel frame 5. Specifically, the protective member 14 is attached to the front - side cab support frame 5C that constitutes the swivel frame 5, and covers the periphery of the wiper movable mechanism 13 that constitutes the wiper device 9. As shown in FIGS. 3 to 7, the protective member 14 is composed of a lower plate 15 as a lower - side protective portion, a front - side fence 16 as a front - side protective portion, and left - hand and right - hand side plates 17 and 18 as side - protective portions. The lower plate 15 extends from a bracket 12 attached to the front - side cab support frame 5C to the lower side of the wiper movable mechanism 13 and covers the wiper movable mechanism 13 from below. The front - side fence 16 extends upward from the front side of the lower plate 15 and covers the wiper movable mechanism 13 from the front. The left - hand side plate 17 extends obliquely upward from the left - end side of the lower plate 15 and covers the wiper movable mechanism 13 from the left - hand side, and the right - hand side plate 18 extends obliquely upward from the right - end side of the lower plate 15 and covers the wiper movable mechanism 13 from the right - hand side.

[0025] The lower plate 15 as the lower protection member constitutes the base of the protection member 14. The lower plate 15 includes a mounting plate portion 15A attached to the bracket 12, a bent plate portion 15B provided at the front end of the mounting plate portion 15A, and an overhanging plate portion 15C provided at the front end of the bent plate portion 15B. The mounting plate portion 15A is in the shape of a flat plate extending in the left - right direction and is provided with two bolt insertion holes 15D. The bent plate portion 15B protrudes forward while bending obliquely downward from the front end of the mounting plate portion 15A, ensuring the strength of the lower plate 15. The bent plate portion 15B is set to have a smaller length dimension in the left - right direction than the mounting plate portion 15A. The overhanging plate portion 15C is composed of a flat plate body and protrudes forward from the front end of the bent plate portion 15B. The overhanging plate portion 15C has the same length dimension in the left - right direction as the bent plate portion 15B. A left side plate 17 is integrally formed on the left end side of the overhanging plate portion 15C, and a right side plate 18 is integrally formed on the right end side of the overhanging plate portion 15C.

[0026] The lower plate 15 is fixed to the lower surface 12B of the bracket 12 by screwing a bolt 15E inserted through the bolt insertion hole 15D of the mounting plate portion 15A to the bracket 12, and is attached to the swing frame 5 via the bracket 12. As shown in FIG. 5, the length dimension A in the left - right direction of the overhanging plate portion 15C of the lower plate 15 is set to a length dimension that covers the lower end side of the parallel link 13A constituting the wiper movement mechanism 13 over the entire left - right direction. Thereby, the overhanging plate portion 15C of the lower plate 15 covers the lower end side of the parallel link 13A constituting the wiper movement mechanism 13, the actuator - side connecting portion 13B, and the output shaft 11A of the electric actuator 11 from below.

[0027] The front fence 16 as the front protection part protrudes vertically upward from in front of the front end 15F of the lower plate 15 (the overhanging plate part 15C). The front fence 16 has a base end side welded to the lower surface of the overhanging plate part 15C, and a columnar left and right shaft body 16A whose tip side is bent vertically upward from the overhanging plate part 15C, and a connecting part 16B connecting between the tips (upper ends) of the left and right shaft bodies 16A. As shown in FIG. 4, the rear end 16C of the connecting part 16B of the front fence 16 faces the lower end side of the parallel link 13A constituting the wiper movement mechanism 13 and the actuator side connecting part 13B with a predetermined first interval B in the front-rear direction. Thereby, the front fence 16 covers the lower end side of the parallel link 13A constituting the wiper movement mechanism 13 and the actuator side connecting part 13B from the front.

[0028] Here, as shown in FIG. 4, the angle θ1 formed by the lower plate 15 constituting the protection member 14 and the bent part of the front fence 16 is set to 90 degrees or less. Thereby, it suppresses the first interval B formed between the rear end 16C of the connecting part 16B of the front fence 16 and the lower end side of the parallel link 13A and the actuator side connecting part 13B constituting the wiper movement mechanism 13 from becoming excessive, and prevents sediment and the like from easily accumulating between the front fence 16 and the parallel link 13A.

[0029] The left side plate 17 and the right side plate 18 as the left and right side protection parts are integrally formed at both left and right ends in the lateral direction of the overhanging plate part 15C constituting the lower plate 15. The left side plate 17 is integrally formed at the left end of the overhanging plate part 15C by bending an extended part extending leftward from the overhanging plate part 15C of the lower plate 15 obliquely upward to the left. The right side plate 18 is integrally formed at the right end of the overhanging plate part 15C by bending an extended part extending rightward from the overhanging plate part 15C of the lower plate 15 obliquely upward to the right.

[0030] The left side plate 17 covers the lower end side of the parallel link 13A (the first link 13A1) that constitutes the wiper drive mechanism 13 and the actuator side connecting portion 13B (the first connecting portion 13B1) from the left side. Here, as shown in FIG. 5, when the parallel link 13A swings and approaches the left side plate 17 most during the operation of the wiper device 9, a straight line parallel to the first link 13A1 of the parallel link 13A passing through the upper end 17A of the left side plate 17 is defined as L1, and the angle at which the overhanging plate portion 15C of the lower plate 15 intersects the left side plate 17 is defined as θ2. The angle θ2 is set within a range where the upper end 17A of the left side plate 17 is positioned between the straight line L1 and the first link 13A1. That is, the angle θ2 is set such that the distance between the left side plate 17 and the first link 13A1 becomes narrower toward the upper end 17A of the left side plate 17 in a state where the parallel link 13A swings and approaches the left side plate 17 most.

[0031] The right side plate 18 covers the lower end side of the parallel link 13A (the second link 13A2) that constitutes the wiper drive mechanism 13 and the actuator side connecting portion 13B (the second connecting portion 13B2) from the right side. Here, as shown by the dashed two-dot line in FIG. 5, when the parallel link 13A swings and approaches the right side plate 18 most during the operation of the wiper device 9, a straight line parallel to the second link 13A2 of the parallel link 13A passing through the upper end 18A of the right side plate 18 is defined as L2, and the angle at which the overhanging plate portion 15C of the lower plate 15 intersects the right side plate 18 is defined as θ3. The angle θ3 is set within a range where the upper end 18A of the right side plate 18 is positioned between the straight line L2 and the second link 13A2. That is, the angle θ3 is set such that the distance between the right side plate 18 and the second link 13A2 becomes narrower toward the upper end 18A of the right side plate 18 in a state where the parallel link 13A swings and approaches the right side plate 18 most.

[0032] Thereby, it is possible to suppress an excessive increase in the distance between the left side plate 17 and the parallel link 13A (the first link 13A1) and the distance between the right side plate 18 and the parallel link 13A (the second link 13A2), and a configuration is provided that can prevent sediment or the like from easily accumulating between the left side plate 17 and the right side plate 18 and the parallel link 13A.

[0033] Further, as shown in FIG. 4, the rear end 17B of the left side plate 17 and the rear end 18B of the right side plate 18 face the front surface 8D of the narrow portion 8A constituting the under-cab front cover 8 with a predetermined second interval C in the front-rear direction. On the other hand, the first interval B in the front-rear direction between the lower end side of the parallel link 13A and the actuator-side connecting portion 13B and the front side fence 16 (rear end 16C) is set larger than the above-described second interval C (B > C).

[0034] Accordingly, for example, when the hydraulic excavator 1 is traveling, even if the earth and sand, rocks, etc. bounced up by the crawler 2A collide with the front side fence 16 of the protection member 14 and the front side fence 16 is deformed or displaced rearward, before the front side fence 16 contacts the actuator-side connecting portion 13B of the parallel link 13A, the rear end 17B of the left side plate 17 and the rear end 18B of the right side plate 18 abut against the front surface 8D of the narrow portion 8A constituting the under-cab front cover 8. Thereby, it is configured to suppress a large load from acting on the actuator-side connecting portion 13B of the parallel link 13A and protect the parallel link 13A.

[0035] Moreover, as shown in FIG. 5, the interval D between the left and right shaft bodies 16A constituting the front side fence 16 is set smaller than the length dimension A in the left-right direction of the overhanging plate portion 15C constituting the lower plate 15 (D < A). For this reason, appropriate gaps 19 are respectively formed between the left side plate 17 provided at the left end portion of the overhanging plate portion 15C and the left shaft body 16A, and between the right side plate 18 provided at the right end portion of the overhanging plate portion 15C and the right shaft body 16A.

[0036] Accordingly, when performing excavation work or the like using the hydraulic excavator 1, even if earth and sand or the like falls on the overhanging plate portion 15C of the lower plate 15, the earth and sand that has fallen on the overhanging plate portion 15C can be discharged to the outside through the gaps 19 by the traveling operation of the hydraulic excavator 1 or the turning operation of the upper swing body 3. Further, for example, when the operator of the hydraulic excavator 1 performs a cleaning operation, the earth and sand that has fallen on the overhanging plate portion 15C can be easily discharged through the gaps 19.

[0037] The hydraulic excavator 1 according to this embodiment has the configuration as described above, and its operation will be described below.

[0038] The operator of the hydraulic excavator 1 gets into the cab 7 and sits on the driver's seat, and drives the hydraulic excavator 1 to the work site by operating, for example, the travel lever - pedal device. When the hydraulic excavator 1 moves to the work site, the operator visually observes the surroundings of the hydraulic excavator 1 through the front window glass 7F and the like, and drives the working device 4 by operating the operation lever device and the like to perform earth - excavation work and the like.

[0039] Here, when water droplets, dirt, etc. adhere to the front window glass 7F, the operator operates the electric actuator 11 of the wiper device 9. The power (rotational force) of the output shaft 11A of the electric actuator 11 is transmitted to the actuator - side connecting portion 13B (first connecting portion 13B1) of the wiper movable mechanism 13, and the parallel link 13A swings in the left - right direction around the output shaft 11A of the electric actuator 11. In this way, the wiper blade 10 connected to the blade - side connecting portion 13C moves in the left - right direction while maintaining a vertical posture, and wipes off dirt, water droplets, etc. adhering to the front window glass 7F, thereby ensuring a good field of view for the operator.

[0040] Here, the electric actuator 11 of the wiper device 9 is arranged between the front - side cab support frame 5C of the swing frame 5 and the lower - cab front cover 8 (narrow portion 8A). The output shaft 11A of the electric actuator 11 projects to the outside (front) of the lower - cab front cover 8 through the opening 8C formed in the lower - cab front cover 8, and the space between the output shaft 11A and the wiper blade 10 is connected via the wiper movable mechanism 13 outside the lower - cab front cover 8. When the hydraulic excavator 1 is traveling, earth and sand are splashed up and scattered by the crawler 2A, and a part of it flies toward the lower - cab front cover 8 and the like. Therefore, there is a risk that the flying earth and sand may collide with the wiper movable mechanism 13 and the like arranged outside the lower - cab front cover 8.

[0041] In contrast, in the present embodiment, a protective member 14 including a lower plate 15, a front fence 16, a left side plate 17, and a right side plate 18 is provided on the front cab support frame 5C that constitutes the swing frame 5. The lower plate 15 covers the wiper drive mechanism 13 from below, the front fence 16 covers the wiper drive mechanism 13 from the front, and the left side plate 17 and the right side plate 18 cover the wiper drive mechanism 13 from the left side and the right side, respectively. Therefore, the sediment flying from below toward the wiper drive mechanism 13 can be blocked by the lower plate 15 of the protective member 14, and the sediment flying from the front toward the wiper drive mechanism 13 can be blocked by the front fence 16. Also, the sediment flying from the left side toward the wiper drive mechanism 13 can be blocked by the left side plate 17, and the sediment flying from the right side toward the wiper drive mechanism 13 can be blocked by the right side plate 18.

[0042] In this way, the lower part of the wiper drive mechanism 13 disposed outside the lower front cover 8 of the cab, specifically, the lower end side of the parallel link 13A that constitutes the wiper drive mechanism 13, the actuator side connecting portion 13B, and the output shaft 11A of the electric actuator 11 are always covered by the protective member 14. As a result, it is possible to suppress the wiper drive mechanism 13 from being damaged due to the impact of sediment during the traveling or excavation work of the hydraulic excavator 1, and the wiper device 9 can be stably operated over a long period of time.

[0043] In this case, the angle θ1 formed by the lower plate 15 and the front fence 16 that constitute the protective member 14 is set to 90 degrees or less. Thereby, it is possible to suppress the first interval B formed between the rear end 16C of the front fence 16 and the lower end side of the parallel link 13A and the actuator side connecting portion 13B that constitute the wiper drive mechanism 13 from becoming excessive. As a result, it is possible to prevent sediment falling from above during excavation work or the like from being easily deposited between the front fence 16 and the parallel link 13A.

[0044] Further, a first interval B between the rear end 16C of the front fence 16, the lower end side of the parallel link 13A constituting the wiper movable mechanism 13, and the actuator side connecting portion 13B is set larger than a second interval C between the rear end 17B of the left side plate 17 and the rear end 18B of the right side plate 18, and the front surface 8D of the narrow portion 8A constituting the under-cab front cover 8 (see FIG. 4). Thereby, even if the earth and sand, rocks, etc. bounced up by the crawler 2A collide with the front fence 16 of the protection member 14 and the front fence 16 is deformed or displaced rearward, before the front fence 16 contacts the actuator side connecting portion 13B of the parallel link 13A, the rear end 17B of the left side plate 17 and the rear end 18B of the right side plate 18 abut against the front surface 8D of the narrow portion 8A constituting the under-cab front cover 8. As a result, it is possible to suppress a large load from acting on the lower end side of the parallel link 13A, the actuator side connecting portion 13B, etc., and protect the parallel link 13A.

[0045] Also, an interval D between the left and right shaft bodies 16A constituting the front fence 16 is set smaller than a left-right length dimension A of the overhanging plate portion 15C constituting the lower plate 15. For this reason, appropriate gaps 19 are respectively formed between the left side plate 17 provided at the left end portion of the overhanging plate portion 15C and the left shaft body 16A, and between the right side plate 18 provided at the right end portion of the overhanging plate portion 15C and the right shaft body 16A. Thereby, even if earth and sand etc. fall on the overhanging plate portion 15C of the lower plate 15, the earth and sand that has fallen on the overhanging plate portion 15C can be discharged to the outside through the gaps 19 by the traveling operation of the hydraulic excavator 1 or the slewing operation of the upper slewing body 3. Further, for example, when an operator of the hydraulic excavator 1 performs a cleaning operation, the earth and sand that has fallen on the overhanging plate portion 15C can be easily discharged through the gaps 19. As a result, it is possible to suppress the deposition of earth and sand etc. on the overhanging plate portion 15C and protect the actuator side connecting portion 13B etc. of the parallel link 13A.

[0046] Furthermore, when the angle at which the overhanging plate portion 15C of the lower plate 15 intersects with the left side plate 17 is θ2, the angle θ2 is set such that in the state where the parallel link 13A swings and approaches the left side plate 17 most closely, the distance between the left side plate 17 and the parallel link 13A (the first link 13A1) becomes narrower toward the upper end 17A of the left side plate 17. Also, when the angle at which the overhanging plate portion 15C of the lower plate 15 intersects with the right side plate 18 is θ3, the angle θ3 is set such that in the state where the parallel link 13A swings and approaches the right side plate 18 most closely, the distance between the right side plate 18 and the parallel link 13A (the second link 13A2) becomes narrower toward the upper end 18A of the right side plate 18. Thereby, it is possible to suppress the distance between the left side plate 17 and the right side plate 18 and the parallel link 13A from becoming excessive. As a result, it is possible to prevent sediment such as earth and sand from easily accumulating between the left side plate 17 and the right side plate 18 and the parallel link 13A, and the wiper movable mechanism 13 can be stably operated over a long period of time.

[0047] Thus, in the embodiment, a self - propelled vehicle body, a cab 7 disposed on the front side of the vehicle body and provided with a front window glass 7F, and a wiper device 9 for wiping the dirt on the front window glass 7F are provided. The wiper device 9 includes a wiper blade 10 that moves in contact with the front window glass 7F and a wiper movable mechanism 13 that is attached to the vehicle body and transmits the power from the electric actuator 11 to the wiper blade 10. In the construction machine configured as such, a protective member 14 that covers the periphery of the wiper movable mechanism 13 is provided on the front end side of the vehicle body. The protective member 14 is disposed below the wiper movable mechanism 13 and has a lower plate 15 that covers the wiper movable mechanism 13 from below.

[0048] According to this configuration, the sediment flying downward toward the wiper movable mechanism 13 can be blocked by the lower plate 15 of the protective member 14, and the wiper movable mechanism 13 can be protected from the sediment.

[0049] In the embodiment, the protection member 14 extends upward from the front side of the lower plate 15 and has a front fence 16 that covers the wiper movable mechanism 13 from the front. According to this configuration, the sediment flying from the front toward the wiper movable mechanism 13 can be blocked by the front fence 16 of the protection member 14, and the wiper movable mechanism 13 can be protected from the sediment.

[0050] In the embodiment, the protection member 14 extends upward from both sides in the left - right direction of the lower plate 15 and has a left side plate 17 and a right side plate 18 that cover the wiper movable mechanism 13 from the left - right direction. According to this configuration, the sediment flying from the left side toward the wiper movable mechanism 13 can be blocked by the left side plate 17, and the sediment flying from the right side toward the wiper movable mechanism 13 can be blocked by the right side plate 18.

[0051] In the embodiment, the lower protection part of the protection member 14 is constituted by a lower plate 15 that extends from the front end of the swing frame 5 to the lower side of the wiper movable mechanism 13, the left and right side protection parts of the protection member 14 are constituted by a left side plate 17 and a right side plate 18 that extend upward from both sides in the left - right direction of the lower plate 15, and the front protection part of the protection member 14 is constituted by a front fence 16 that has a plurality of shaft bodies 16A and extends upward from the front side of the lower plate 15. According to this configuration, the lower plate 15, the left side plate 17 and the right side plate 18, and the front fence 16 can constitute the protection member 14 that covers the periphery of the wiper movable mechanism 13.

[0052] The lower plate 15 has a length dimension that covers the lower end side of the wiper movable mechanism 13 over the entire range in the left - right direction. According to this configuration, the sediment flying from below toward the wiper movable mechanism 13 can be surely blocked by the lower plate 15, and the wiper movable mechanism 13 can be protected.

[0053] In the embodiment, the rear end 16C of the front fence 16 faces the wiper drive mechanism 13 in the front-rear direction with a predetermined first interval, the rear end 17B of the left side plate 17 and the rear end 18B of the right side plate 18 face the under-cab front cover 8 in the front-rear direction with a predetermined second interval, and the first interval is set to be larger than the second interval. According to this configuration, even if the front fence 16 is deformed or displaced rearward due to the collision of earth and sand or the like, before the front fence 16 contacts the wiper drive mechanism 13, the rear end 17B of the left side plate 17 and the rear end 18B of the right side plate 18 abut against the under-cab front cover 8. Thereby, it is possible to suppress a large load from acting on the wiper drive mechanism 13 and protect the wiper drive mechanism 13.

[0054] In the embodiment, the wiper drive mechanism 13 is configured to include a parallel link 13A that has one end attached to the electric actuator 11 and the other end attached to the wiper blade 10 and swings along the front window glass 7F. The angle formed by the left side plate 17 and the lower plate 15 of the protection member 14 is set such that in a state where the parallel link 13A swings and is closest to the left side plate 17, the interval between the left side plate 17 and the parallel link 13A (the first link 13A1) becomes narrower toward the upper end 17A of the left side plate 17. Also, the angle formed by the right side plate 18 and the lower plate 15 of the protection member 14 is set such that in a state where the parallel link 13A swings and is closest to the right side plate 18, the interval between the right side plate 18 and the parallel link 13A (the second link 13A2) becomes narrower toward the upper end 18A of the right side plate 18. According to this configuration, it is possible to suppress the interval formed between the left side plate 17 and the right side plate 18 and the wiper drive mechanism 13 from becoming too large, and prevent the earth and sand that has fallen from above during excavation work or the like from entering between the left side plate 17 and the right side plate 18 and the wiper drive mechanism 13. Also, in the vicinity of the lower plate 15, the interval formed between the left side plate 17 and the right side plate 18 and the wiper drive mechanism 13 is wide, and the intruded earth and sand can be easily discharged. That is, it is possible to prevent the earth and sand that has fallen from above during excavation work or the like from easily accumulating between the front fence 16 and the wiper drive mechanism 13.

[0055] In the embodiment, the front fence 16 rises upward from the lower plate 15 with a predetermined interval from the wiper movable mechanism 13, and the angle formed by the lower plate 15 and the front fence 16 is 90 degrees or less. According to this configuration, it is possible to suppress an excessive interval formed between the front fence 16 and the wiper movable mechanism 13, and prevent sediment falling from above during excavation work or the like from easily accumulating between the front fence 16 and the parallel link 13A.

[0056] In the embodiment, the case where the protective member 14 is attached to the front cab support frame 5C of the swing frame 5 is illustrated. However, the present invention is not limited to this, and for example, a configuration in which the protective member is attached to the lower end side of the front surface constituting the cab 7 may be adopted.

[0057] Further, in the embodiment, the case where the front window glass 7F formed using tempered glass or the like is attached to the front surface 7A of the cab 7 is illustrated. However, the present invention is not limited to this, and for example, a configuration in which a transparent front plate formed using a transparent resin material is attached may be adopted.

[0058] Furthermore, in the embodiment, the crawler-type hydraulic excavator 1 including the cab 7 is illustrated as an application target of the protective member 14. However, the present invention is not limited to this, and for example, it can be widely applied to construction machines including cabs such as wheel-type hydraulic excavators and hydraulic cranes.

Explanation of reference numerals

[0059] 2 Lower traveling body 3 Upper swing body 7 Cab 7F Front window glass (transparent front plate) 9 Wiper device 10 Wiper blade 11 Electric actuator (power source) 13 Wiper movable mechanism 13A Parallel link 14 Protective member 15 Lower plate (lower protective part) 16 Front fence (front protective part) 17 Left side plate (side protective part) 18 Right side plate (lateral protection part)

Claims

1. A construction machine comprising a self-propelled vehicle body, a cab disposed on the front side of the vehicle body and provided with a transparent front plate, and a wiper device for wiping dirt off the transparent front plate, wherein the wiper device includes a wiper blade that moves in contact with the transparent front plate and a wiper movable mechanism that is attached to the vehicle body and transmits power from a power source to the wiper blade. A protective member for covering the periphery of the wiper movable mechanism is provided on the front end side of the vehicle body. The construction machine is characterized in that the protective member has a lower protective part disposed below the wiper movable mechanism and covering the wiper movable mechanism from below.

2. The construction machine according to claim 1, wherein the protective member has a front protective part that extends upward from the front side of the lower protective part and covers the wiper movable mechanism from the front.

3. The construction machine according to claim 1, wherein the protective member has left and right side protective parts that extend upward from both sides in the left-right direction of the lower protective part and cover the wiper movable mechanism from the left and right directions.

4. The protective member has a front protective part that extends upward from the front side of the lower protective part and covers the wiper movable mechanism from the front, and left and right side protective parts that extend upward from both sides in the left-right direction of the lower protective part and cover the wiper movable mechanism from the left and right directions. The lower protective part is constituted by a lower plate that extends from the front end of the vehicle body to below the wiper movable mechanism. The left and right side protective parts are constituted by left and right side plates that extend upward from both sides in the left-right direction of the lower plate. The front protective part is constituted by a front fence having a plurality of shaft bodies and extending upward from the front side of the lower plate. The construction machine according to claim 1 is characterized in this regard.

5. The construction machine according to claim 1, wherein the lower protective part has a length dimension that covers the lower end side of the wiper movable mechanism over the entire left-right direction.

6. The protective member has a front protective part that extends upward from the front side of the lower protective part and covers the wiper movable mechanism from the front, and left and right side protective parts that extend upward from both sides in the left-right direction of the lower protective part and cover the wiper movable mechanism from the left and right directions. The rear end of the front protective part faces the wiper movable mechanism in the front-rear direction with a predetermined first interval. The rear end of the side protective part faces the vehicle body in the front-rear direction with a predetermined second interval. The construction machine according to claim 1, wherein the first interval is set to be larger than the second interval.

7. The wiper moving mechanism is configured to include a parallel link having one end attached to the power source and the other end attached to the wiper blade, and the parallel link swings along the transparent front plate. The construction machine according to claim 3, wherein the angle formed by the side protection part and the lower protection part of the protection member is set such that the distance between the side protection part and the parallel link becomes narrower toward the upper end of the side protection part in a state where the parallel link swings and is closest to the side protection part.

8. The front protection part rises upward from the lower protection part with a predetermined interval from the wiper moving mechanism. The construction machine according to claim 2, wherein the angle formed by the lower protection part and the front protection part is 90 degrees or less.

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