Construction machinery

Abstract

To provide a construction machinery in which the enlargement of a rotation-limit mechanism that limits the rotation of an engine cover can be prevented.SOLUTION: An engine cover 9 has an operator seat 10 arranged at a position in the upper area and corresponding to the middle of the width. The engine cover 9 is mounted on a revolving frame 5 (counterweight 5C) in such a way that it can rotate up and down between a close position covering an engine 7 from the top and an open position exposing the engine 7 outside. A rotation-limit mechanism 31 prevents the engine cover 9 from rotating towards the close position when the engine cover 9 is at the open position. The revolving frame 5 (the counterweight 5C) has a stopper mechanism 29 with a rubber stopper 23 at a position near to the rotation center and corresponding to the middle of the width of the engine cover 9. The rubber stopper 23 comes to contact with a member (a butting piece 24E of a bracket 24 on the cover side) of the engine cover 9, thereby preventing the engine cover 9 from rotating beyond the designated open angle.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to construction machines such as hydraulic excavators. [Background technology]

[0002] Generally, a hydraulic excavator, which is a representative example of a construction machine, comprises a self-propelled lower traveling body and an upper rotating body rotatably mounted on the lower traveling body. The lower traveling body and the upper rotating body form the vehicle body of the hydraulic excavator. A working device is provided at the front of the upper rotating body so that it can be raised and lowered. Various devices including a prime mover such as an engine are mounted on the upper rotating body. The prime mover is covered by a prime mover cover which can be opened and closed.

[0003] When opening the prime mover cover for daily inspection, internal maintenance, etc., it is necessary to hold the prime mover cover in a specified open state so that the prime mover cover does not open or close unintentionally due to the influence of wind, etc. For example, the work machine of Patent Document 1 has a slide bar (stay) and a slide rail (stay guide) provided between the prime mover cover and the building cover.

[0004] When the motor cover is operated, the slide bar slides along the slide rail. The slide rail has a linear guide section that guides the tip of the slide bar until the motor cover is fully open, and a V-shaped guide that holds the tip of the slide bar in place due to the weight of the motor cover. When the motor cover is opened, the tip of the slide bar moves along the linear guide section and engages with the end of the V-shaped guide. This makes it possible to hold the motor cover in the open state at a large opening angle. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-069673 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, for example, in a configuration in which a part such as a driver's seat is mounted on the top of the prime mover cover, most of the weight of the heavy prime mover cover and the parts mounted on the prime mover cover is applied to the engagement part between the tip of the slide bar and the V-shaped guide of the slide rail. This requires a stronger configuration to prevent the slide bar and slide rail from being deformed or damaged, which may lead to an increase in the size of the slide bar and slide rail.

[0007] An object of the present invention is to provide a construction machine that can prevent an increase in size of a rotation restricting mechanism that restricts the rotation of a motor cover. [Means for solving the problem]

[0008] The present invention relates to a construction machine comprising a body component to which a working device is attached, a prime mover attached to the body component, a prime mover cover attached to the body component so as to be rotatable in the vertical direction between a closed position which covers the prime mover from above and an open position which exposes the prime mover to the outside, with a driver's seat provided at the top and in a position corresponding to the center in the width direction, and a rotation restriction mechanism which restricts the prime mover cover from rotating toward the closed position when the prime mover cover is in the open position, in which a stopper mechanism is provided on one of the body component or the prime mover cover, on the rotation center side of the prime mover cover and in a position corresponding to the center in the width direction, for abutting against the other of the body component or the prime mover cover to restrict the prime mover cover from rotating more than a predetermined opening angle. Effect of the Invention

[0009] According to the present invention, it is possible to suppress an increase in size of the rotation restricting mechanism that restricts the rotation of the motor cover. [Brief description of the drawings]

[0010] [Figure 1]FIG. 1 is a perspective view showing a hydraulic excavator according to an embodiment. [Diagram 2] FIG. 2 is a perspective view showing the counterweight-integrated revolving frame, the engine, the hydraulic oil tank, the battery, the battery bracket, etc. [Diagram 3] 1 is a cross-sectional view showing the driver's seat, the engine cover, the battery bracket, the rotation restriction mechanism, the connecting device, etc. [Figure 4] FIG. 4 is a perspective view of the engine cover seen from below. [Diagram 5] FIG. [Figure 6] 4 is a perspective view showing a vehicle body side bracket and a rubber stopper that constitute the connecting device. FIG. [Figure 7] 4 is a cross-sectional view taken from the same direction as FIG. 3, showing the state in which the motor cover is opened to a position where the center of gravity G of the entire motor cover and its associated members exceeds a perpendicular line (imaginary line AA) passing through the rotation center O of the motor cover. [Figure 8] 8 is an enlarged cross-sectional view showing a rotation restricting mechanism, a connecting device, etc. in FIG. 7. [Figure 9] 4 is a cross-sectional view taken from the same direction as FIG. 3, showing a state in which the engine cover is opened to a maximum open position. [Figure 10] 10 is an enlarged cross-sectional view showing a rotation restricting mechanism, a connecting device, etc. in FIG. 9. [Figure 11] FIG. 1 is a perspective view showing the counterweight-integrated revolving frame, the engine, the coupling device (the vehicle body-side bracket, the rubber stopper), etc. [Figure 12] 12 is an enlarged cross-sectional view showing a connecting device (a bracket on a vehicle body side, a rubber stopper) and the like in FIG. 11. [Figure 13] FIG. 4 is a perspective view showing a coupling device and the like when the motor cover is in a closed position. [Figure 14] FIG. 4 is a perspective view showing a coupling device and the like when the motor cover is in an open position. [Figure 15] FIG. 4 is a cross-sectional view showing a coupling device and the like when the motor cover is in a closed position. [Figure 16] FIG. 4 is a cross-sectional view showing a coupling device and the like when the motor cover is in an open position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiment will be described in detail with reference to the attached drawings, taking as an example a case where the embodiment is applied to a hydraulic excavator, which is a representative construction machine (work machine), and more specifically, to a small hydraulic excavator. In the following description, the front-to-rear direction of the hydraulic excavator 1 refers to the front side as the working device 4 side, and the rear side as the counterweight 5C side, which is opposite to the working device 4. The left-to-right direction of the hydraulic excavator 1 refers to the direction perpendicular to the front-to-rear direction.

[0012] The hydraulic excavator 1 as a construction machine (work machine) is used, for example, at work sites for civil engineering, demolition, underground construction, etc. The hydraulic excavator 1 of the embodiment is configured as a mini excavator with a machine weight (total weight) of, for example, about 1 ton so that it can be used for demolition work inside buildings and excavation work in narrow places such as alleys.

[0013] In Fig. 1, the hydraulic excavator 1 comprises a crawler-type lower traveling body 2 which is capable of traveling, an upper rotating body 3 which is rotatably mounted on the lower traveling body 2, and a working device 4 which is provided on the upper rotating body 3. The lower traveling body 2 and the upper rotating body 3 constitute a vehicle body of the hydraulic excavator 1. The vehicle body is capable of traveling and rotating. A swing-type working device 4 is attached to the front side of the upper rotating body 3 so as to be able to swing. The hydraulic excavator 1 performs work such as excavating earth and sand using the working device 4.

[0014] The lower traveling body 2 is configured to include, for example, crawler belts 2A formed by attaching a plurality of shoes to endless track links, and left and right traveling hydraulic motors (not shown) that rotate the crawler belts 2A to travel (self-propel) the hydraulic excavator 1. A rotating device configured to include a rotating bearing and a rotating hydraulic motor is provided between the lower traveling body 2 and the upper rotating body 3.

[0015] The working device 4, also called a front device or a working machine, has a swing post 4A that is provided on the front side of a revolving frame 5 so as to be swingable in the left-right direction. A boom 4B is rotatably attached to the swing post 4A, an arm 4C is rotatably attached to the tip of the boom 4B, and a bucket 4D as a working tool is rotatably attached to the tip of the arm 4C. The working device 4 also includes a swing cylinder (not shown) that swings the swing post 4A, a boom cylinder 4E that rotates the boom 4B, an arm cylinder 4F that rotates the arm 4C, and a bucket cylinder 4G as a working tool cylinder that rotates the bucket 4D.

[0016] The upper rotating body 3 is mounted on the lower traveling body 2 so as to be rotatable. The upper rotating body 3 rotates on the lower traveling body 2 by being driven by a hydraulic motor for rotation of the rotation device. The upper rotating body 3 includes, for example, a counterweight-integrated rotating frame 5 (hereinafter referred to as the rotating frame 5) as a vehicle body constituent member, an engine 7 (FIGS. 2 and 7) serving as a prime mover of the hydraulic excavator 1, a prime mover cover 9 covering the engine 7, a driver's seat 10 provided above the prime mover cover 9 and in which an operator sits, and a travel lever 13 and an operation lever 14 provided in front of the driver's seat 10 for operating the hydraulic excavator 1. The operator can operate the travel lever 13 and the operation lever 14 to travel using the lower traveling body 2, rotate the upper rotating body 3, excavate using the operation device 4, and the like.

[0017] 2, the revolving frame 5 includes a substantially rectangular bottom plate 5A extending in the front-rear direction, a support portion 5B provided at the front portion of the bottom plate 5A so as to protrude forward and support the working device 4 so as to be swingable in the left-right direction, and a counterweight 5C extending in the left-right direction and upward from the rear portion of the bottom plate 5A. The bottom plate 5A, the support portion 5B, and the counterweight 5C are integrally formed by, for example, casting.

[0018] The counterweight 5C is formed as a heavy weight for balancing the weight with the working device 4. In the embodiment, the vehicle body constituent member is a counterweight-integrated revolving frame in which the revolving frame and the counterweight are integrated. However, this is not limiting, and for example, the revolving frame and the counterweight may be formed separately and assembled together. In this case, the revolving frame and the counterweight, which are separate from each other, correspond to the vehicle body constituent member.

[0019] As shown in Fig. 3 etc., a coupling device 21 that rotatably couples the prime mover cover 9 to the revolving frame 5 is provided on the top surface of the counterweight 5C. As shown in Figs. 3, 7 and 9, the prime mover cover 9 is supported openably (rotatably) on the upper part of the counterweight 5C via the coupling device 21. In addition, as shown in Fig. 1, a roll bar 15 is attached to the rear side of the revolving frame 5 (counterweight 5C).

[0020] 1, the side cover 6 is provided so as to surround the periphery of the bottom plate 5A of the revolving frame 5. The side cover 6 is erected with a height dimension substantially equal to that of the counterweight 5C, and is bent into a U-shape so that the rear side is open.

[0021] The engine 7 as a prime mover is provided at the rear of the revolving frame 5. The engine 7 is located in front of the counterweight 5C and is disposed in a horizontal state extending in the left-right direction. The engine 7 is attached to the revolving frame 5 in a vibration-proof state. The engine 7 drives a hydraulic pump (not shown). Note that the prime mover (power source, driving source) for driving the hydraulic pump can be constituted by the engine 7 alone, which is an internal combustion engine, or it may be constituted by, for example, "an engine and an electric motor" or "an electric motor alone". In other words, the prime mover corresponds to, for example, an "engine", "an engine and an electric motor", or "an electric motor".

[0022] The hydraulic pump draws in hydraulic oil stored in a hydraulic oil tank 8 (FIG. 2) and discharges (supplies) the pressurized oil toward a control valve device (not shown). The hydraulic pump supplies the pressurized oil to various hydraulic actuators (hydraulic cylinders, hydraulic motors) such as the boom cylinder 4E via the control valve device. The control valve device is a control valve group consisting of multiple directional control valves. The control valve device distributes the pressurized oil discharged from the hydraulic pump to multiple hydraulic actuators (hydraulic cylinders, hydraulic motors) such as the boom cylinder 4E in response to the operation of the travel lever 13 and the work lever 14. This enables the hydraulic excavator 1 to travel, swing, excavate, etc.

[0023] 2, the hydraulic oil tank 8 is provided on the front right side of the rotating frame 5. The hydraulic oil tank 8 is a roughly rectangular parallelepiped container extending in the front-rear direction, and stores hydraulic oil to be supplied to various hydraulic actuators mounted on the hydraulic excavator 1.

[0024] The prime mover cover 9 covers the engine 7 in an openable and closable manner. The prime mover cover 9 is formed as an openable cover whose front side can be opened and closed in the vertical direction with the rear side as a fulcrum. The prime mover cover 9 is formed in a box shape with an open bottom side, and is made up of a front surface 9A, a rear surface 9B, a left surface 9C, a right surface 9D, and a top surface 9E. The lower part of the front surface 9A forms a front surface 9A1 that extends vertically at the forefront of the prime mover cover 9. The top surface 9E of the prime mover cover 9 is formed to be gently curved and downwardly slanting.

[0025] A coupling device 21 is provided at the bottom of the rear portion 9B, which serves as a fulcrum when opening and closing the prime mover cover 9. The prime mover cover 9 is rotatably attached to the counterweight 5C via the coupling device 21. Meanwhile, an opening / closing lever 9F (FIGS. 7 and 9) is provided at the front portion 9A. By operating the opening / closing lever 9F, the prime mover cover 9 is released from its connection (lock) to a structure (catch) on the revolving frame 5 side, and can be opened upward. The opening / closing lever 9F is disposed at a position corresponding to the center of the prime mover cover 9 in the width direction. In this case, the opening / closing lever 9F is disposed at a position overlapping with the driver's seat 10 in the width direction of the prime mover cover 9 (left and right direction of the upper revolving body 3).

[0026] The driver's seat 10 is provided above the engine cover 9. In this case, the driver's seat 10 is provided at a position corresponding to the upper part of the engine cover 9 and the center in the width direction. The driver's seat 10 includes a seat portion 10A and a backrest portion 10B extending upward from the rear portion of the seat portion 10A. The driver's seat 10 is movable in the front-rear direction so that the seating position can be adjusted according to the operator's body shape and operating posture.

[0027] The floor 11 is provided extending forward from the engine cover 9. The lever stand 12 is provided upright at the front of the floor 11. On the upper part of the lever stand 12, a travel lever 13 which is an operating lever for travelling and an operation lever 14 which is an operating lever for operation are provided.

[0028] The roll bar 15 is attached to the rear side of the counterweight 5C of the revolving frame 5. The roll bar 15 is composed of an inverted U-shaped strength member that extends to a position higher than the operator sitting in the driver's seat 10. The roll bar 15 can protect the operator when, for example, a structure falls or the hydraulic excavator 1 is turned upside down. In addition, the roll bar 15 can be rotated horizontally to retract so as not to get in the way when the prime mover cover 9 is opened.

[0029] As shown in FIG. 2 etc., a battery bracket 16 is provided on the rear side of the revolving frame 5. The battery bracket 16 is fixed to the revolving frame 5. The battery bracket 16 constitutes a base on which a battery 17 is placed. The battery bracket 16 includes a lower plate 16A, a left side plate 16B, and a front side plate 16C. As shown in FIG. 3 etc., a guide rail 32 is provided on the left side plate 16B on the surface opposite to the surface facing the battery 17. A rod member 34 is movably attached to the guide rail 32. The guide rail 32 and the rod member 34 constitute a rotation restriction mechanism 31, which will be described later.

[0030] Next, the "mover cover 9," "connecting device 21 that rotatably supports the motor cover 9 on the revolving frame 5 (counterweight 5C)," and "rotation restriction mechanism 31 that restricts the rotation of the motor cover 9" will be described.

[0031] As shown in Figures 1 and 3, a driver's seat 10 on which an operator sits is attached to the prime mover cover 9. A coupling device 21 is provided between the prime mover cover 9 and the revolving frame 5 (counterweight 5C). A rotation restricting mechanism 31 is provided between the prime mover cover 9 and the battery bracket 16. The prime mover cover 9 is formed as a cup-shaped cover with the upper sides of its rectangular cylindrical peripheral surfaces (front surface 9A, rear surface 9B, left surface 9C, right surface 9D) closed by an upper surface 9E.

[0032] The rear surface 9B of the motor cover 9 is attached to the upper surface of the counterweight 5C via the connecting device 21. The front side of the motor cover 9 can be opened and closed up and down with the connecting device 21 as the rotation center O. When the motor cover 9 is in the closed state, the lower end of the front surface 9A of the motor cover 9 faces the floor 11, the lower ends of the left surface 9C and right surface 9D face the bottom plate 5A (or side cover 6) of the revolving frame 5, and the lower end of the rear surface 9B faces the counterweight 5C of the revolving frame 5.

[0033] The coupling device 21 comprises a vehicle body side bracket 22 attached to the swivel frame 5 (counterweight 5C) on the vehicle body side, a cover side bracket 24 attached to the prime mover cover 9 on the cover side, and a first support shaft 25 and a second support shaft 26 arranged between the vehicle body side bracket 22 and the cover side bracket 24 and supporting them rotatably.

[0034] As shown in Fig. 6, the vehicle body bracket 22 includes a bottom plate portion 22A, a vertical plate portion 22B, a vehicle body first shaft support portion 22C, a vehicle body second shaft support portion 22D, a block stopper 22E as a rigid stopper, and a stopper mounting portion 22F. The bottom plate portion 22A is placed on the upper surface of the counterweight 5C. The vertical plate portion 22B rises upward from the bottom plate portion 22A.

[0035] The vehicle body first shaft support portion 22C is located on one end side in the width direction of the vertical plate portion 22B (for example, the left side in the left-right direction of the vehicle body) and protrudes toward the rear surface portion 9B of the motor cover 9. The vehicle body second shaft support portion 22D is located on the other end side in the width direction of the vertical plate portion 22B (for example, the right side in the left-right direction of the vehicle body) and protrudes toward the rear surface portion 9B of the motor cover 9. The block stopper 22E is provided between the vehicle body first shaft support portion 22C and the vehicle body second shaft support portion 22D.

[0036] The stopper attachment portion 22F is provided between the vehicle body side first shaft support portion 22C and the vehicle body side second shaft support portion 22D. A rubber stopper 23 serving as an elastic stopper is attached to the stopper attachment portion 22F. The vehicle body side first shaft support portion 22C is provided with a vehicle body side first through hole 22C1 through which the first support shaft 25 is inserted. The vehicle body side second shaft support portion 22D is provided with a vehicle body side second through hole 22D1 through which the second support shaft 26 is inserted. The second support shaft 26 is fixed to the vehicle body side second shaft support portion 22D by welding or the like in a state where it is inserted into the vehicle body side second through hole 22D1.

[0037] As shown in Fig. 4, the cover side bracket 24 includes a horizontal plate portion 24A, a cover side first shaft support portion 24B, a cover side second shaft support portion 24C, a U-shaped abutment body 24D, and an abutment piece 24E. The horizontal plate portion 24A is attached to the inner surface of the motor cover 9. The cover side first shaft support portion 24B protrudes downward from the horizontal plate portion 24A. As shown in Figs. 13 and 14, the cover side first shaft support portion 24B faces the vehicle body side first shaft support portion 22C.

[0038] The cover-side second shaft support portion 24C protrudes downward from the horizontal plate portion 24A. As shown in Fig. 13 and Fig. 14, the cover-side second shaft support portion 24C faces the vehicle-side second shaft support portion 22D. The U-shaped abutment body 24D is provided between the cover-side first shaft support portion 24B and the cover-side second shaft support portion 24C. The abutment body 24D abuts against the block stopper 22E to prevent the prime mover cover 9 from rotating any further.

[0039] The abutment piece 24E is provided between the cover side first shaft support portion 24B and the cover side second shaft support portion 24C. The abutment piece 24E abuts against the rubber stopper 23. The cover side first shaft support portion 24B is provided with a cover side first through hole (not shown) through which the first support shaft 25 is inserted. The cover side second shaft support portion 24C is provided with a cover side second through hole 24C1 through which the second support shaft 26 is inserted.

[0040] The cover side bracket 24 is welded to the underside of the rear surface portion 9B of the motor cover 9. The abutment piece 24E is provided at a position where it abuts against the rubber stopper 23 of the vehicle body side bracket 22. The abutment body 24D is provided at a position where it abuts against the block stopper 22E of the vehicle body side bracket 22. When the motor cover 9 is opened from the closed position to the open position, the abutment piece 24E abuts against the rubber stopper 23 before the abutment body 24D and the block stopper 22E abut, and the rubber stopper 23 is deformed.

[0041] This reduces the impact applied to U-shaped abutment body 24D and block stopper 22E when motor cover 9 is forcefully opened, and the load due to the weight of motor cover 9. As shown in Fig. 16, when U-shaped abutment body 24D and block stopper 22E abut against each other, abutment surface 24D1 of abutment body 24D and abutment surface 22E1 of block stopper 22E come into surface contact with each other.

[0042] As shown in Fig. 4 and other figures, the first support shaft 25 has one end which forms a flange portion 25A which protrudes in the radial direction over the entire circumference. The other end of the first support shaft 25 (the side opposite to the flange portion 25A) is provided with a pin hole through which the retaining pin 27 is inserted. In contrast, as shown in Fig. 6, the second support shaft 26 is fixed to the vehicle body side second shaft support portion 22D by welding or the like in a state in which one end of the second support shaft 26 is inserted into the vehicle body side second through hole 22D1 of the vehicle body side second shaft support portion 22D. The other end of the second support shaft 26 is provided with a pin hole through which the retaining pin 27 (Fig. 12 and other figures) is inserted.

[0043] The first support shaft 25 is inserted through the vehicle body side first through hole 22C1 of the vehicle body side first shaft support portion 22C and the cover side first through hole (not shown) of the cover side first shaft support portion 24B, and in this state, the retaining pin 27 is inserted through the pin hole. The second support shaft 26 fixed to the vehicle body side second shaft support portion 22D is inserted through the cover side second through hole 24C1 of the cover side second shaft support portion 24C, and in this state, the retaining pin 27 is inserted through the pin hole of the second support shaft 26. As a result, the cover side bracket 24 is connected to the vehicle body side bracket 22 so as to be rotatable about the support shafts 25, 26. That is, the cover side bracket 24, the vehicle body side bracket 22, the first support shaft 25, and the second support shaft 26 constitute a hinge mechanism 28 that rotatably supports the prime mover cover 9 with respect to the revolving frame 5 (counterweight 5C).

[0044] Additionally, the rubber stopper 23 and block stopper 22E of the vehicle body side bracket 22 and the abutment piece 24E and abutment body 24D of the cover side bracket 24 constitute a stopper mechanism 29 that restricts the rotation of the motor cover 9. The rubber stopper 23 is attached to the stopper attachment portion 22F of the vehicle body side bracket 22. Due to the layout of the vehicle body side bracket 22, the rubber stopper 23 is disposed at a position slightly shifted from the center of the vehicle body side bracket 22 in the width direction.

[0045] That is, in the vehicle body side bracket 22, not only the rubber stopper 23 serving as an elastic stopper but also the metal block stopper 22E serving as a rigid stopper is provided between the vehicle body side first shaft support portion 22C and the vehicle body side second shaft support portion 22D. When only the rubber stopper 23 is provided on the vehicle body side bracket 22, the rubber stopper 23 can be provided at the width direction center of the vehicle body side bracket 22. In either case, the rubber stopper 23 can receive the load of the motor cover 9 and the members that rotate together with the motor cover 9 at the width direction center or a position close to the center of the motor cover 9.

[0046] In this embodiment, the vehicle body side bracket 22 constituting the hinge mechanism 28 is provided with both the rubber stopper 23 serving as an elastic stopper and the metal block stopper 22E serving as a rigid stopper. That is, the stopper mechanism 29 that restricts the rotation of the motor cover 9 is composed of the rubber stopper 23 and the metal block stopper 22E. In this case, the rubber stopper 23 abuts against the abutment piece 24E of the cover side bracket 24 when the motor cover 9 is in the open position, thereby elastically supporting the motor cover 9 and the members that rotate together with the motor cover 9.

[0047] On the other hand, when the motor cover 9 is forcefully opened, the block stopper 22E comes into contact with the abutting body 24D of the cover side bracket 24, thereby preventing the motor cover 9 and the members rotating together with the motor cover 9 from rotating further in the opening direction. Either the elastic stopper (rubber stopper 23) or the rigid stopper (metallic block stopper 22E) may be omitted as necessary. That is, the stopper mechanism may be constituted by an elastic stopper, may be constituted by a rigid stopper, or may be constituted by both an elastic stopper and a rigid stopper.

[0048] Also, for example, when the stopper mechanism is composed of both an elastic stopper and a rigid stopper, the elastic stopper may be provided on the hinge mechanism 28 (e.g., the vehicle body side bracket 22), while the rigid stopper may be provided at a position away from the hinge mechanism 28 (the vehicle body side bracket 22 and the cover side bracket 24). The elastic stopper (rubber stopper 23) that receives the weight of the entire motor cover 9 and its associated members (e.g., the driver's seat 10) when the motor cover 9 is in the open position is preferably provided at the center of the motor cover 9 in the width direction or at a position close to the center. This makes it possible to suppress twisting of the motor cover 9 when the motor cover 9 is in the open position.

[0049] As shown in FIG. 3 and other figures, the rotation restriction mechanism 31 is attached between the revolving frame 5 (more specifically, the battery bracket 16) and the motor cover 9. When the motor cover 9 is in the open position, the rotation restriction mechanism 31 restricts the motor cover 9 from rotating toward the closed position. As shown in FIG. 5 and other figures, the rotation restriction mechanism 31 includes a guide rail 32 attached to the battery bracket 16 on the vehicle body side, a rod support member 33 attached to the motor cover 9 on the cover side, a rod member 34 one end of which is movably attached to the guide hole 32A of the guide rail 32 and the other end of which is rotatably attached to the rod support member 33, and a wire 39 that releases the restriction of the rotation of the motor cover 9 by the rotation restriction mechanism 31. Note that, as shown in FIG. 5, the "one end" and the "other end" of the rod member 34 are not limited to the "end" of the rod member 34, but correspond to a portion having a certain width including the "end" (one end, the other end, one end side, the other end side).

[0050] As shown in FIG. 3 and other figures, the guide rail 32 is attached to the left side plate 16B of the battery bracket 16 by, for example, welding. As a result, the rotation restriction mechanism 31 is arranged biased toward one side (right side) in the width direction within the space (engine room) surrounded by the motor cover 9. The guide rail 32 is provided with a guide hole 32A penetrating in the plate thickness direction. The guide hole 32A has a straight portion 32B that extends linearly and an enlarged portion 32C that serves as a cutout portion. When the guide rail 32 is attached to the battery bracket 16, the straight portion 32B of the guide hole 32A extends horizontally and in the front-rear direction (the direction toward and away from the counterweight 5C). The guide hole 32A has a width dimension that prevents the retaining plate 35 attached to one end of the rod member 34 from falling out. The guide hole 32A guides one end (the tip, the end on the moving side) of the rod member 34 to be movable in the length direction of the guide hole 32A.

[0051] The rod support member 33 is attached to the rear surface portion 9B of the motor cover 9. In this case, the rod support member 33 is disposed at a position corresponding to the guide rail 32 of the battery bracket 16 in the width direction of the motor cover 9. As a result, the rod support member 33 is also disposed biased to one side (right side) in the width direction of the engine room. The rod support member 33 is provided with a through hole in the plate thickness direction, the through hole having an inner diameter larger than the outer diameter dimension of the rod support member 33. The other end (base end, end on the cover side) of the rod member 34 is rotatably attached to the through hole of the rod support member 33.

[0052] The rod member 34 is provided between the battery bracket 16 (more specifically, the guide rail 32) and the prime mover cover 9 (more specifically, the rod support member 33). One end of the rod member 34 is movably attached within the guide hole 32A of the guide rail 32. The other end of the rod member 34 is rotatably attached to the rod support member 33. As a result, the rod member 34 connects between the battery bracket 16 (more specifically, the guide rail 32) and the motor cover 9 (more specifically, the rod support member 33) on one side (the right side) in the width direction of the engine compartment. One end of the rod member 34 moves into the enlarged portion 32C of the guide hole 32A as the motor cover 9 rotates, in order to prevent the motor cover 9 from closing unintentionally when the motor cover 9 is in the open position.

[0053] The rod member 34 is formed by bending both ends of an elongated rod-shaped body made of, for example, a steel rod. That is, one end of the rod member 34 is bent in a direction to enter the guide hole 32A of the guide rail 32. The other end of the rod member 34 is bent in a direction to enter the through hole of the rod support member 33. In this embodiment, both ends of the rod member 34 are bent in the same direction (towards the battery 17, which is the right side of the vehicle body).

[0054] A side ring 36 is fixed to one end of the rod member 34 for positioning the one end with respect to the guide rail 32. A pin hole (not shown) through which a retaining pin (not shown) is inserted is provided at one end of the rod member 34, closer to the tip side than the side ring 36. Two rectangular retaining plates 35 are attached to one end of the rod member 34 so as to sandwich the guide rail 32. The two retaining plates 35 are sandwiched between the side ring 36 and the retaining pins. As a result, one end of the rod member 34 is attached to the guide rail 32 so as to be movable within the guide hole 32A.

[0055] An other-side ring 37 is fixed to the other end of the rod member 34 for positioning the other end with respect to the rod support member 33. Furthermore, a pin hole through which a retaining pin 38 is inserted is provided at the other end of the rod member 34, closer to the tip side than the other-side ring 37. With the other end of the rod member 34 inserted into the through hole, the rod support member 33 is clamped between the other-side ring 37 and the retaining pin 38. In this way, the other end of the rod member 34 is rotatably attached to the rod support member 33 provided on the motor cover 9.

[0056] Further, a wire 39 is attached to one end of the rod member 34. The wire 39 is a restriction release member that releases the restriction imposed by the rotation restriction mechanism 31. One end side (base end side) of the wire 39 is attached to one end of the rod member 34, between the one side ring 36 and the retaining plate 35. The other end side (tip side) of the wire 39 forms a ring-shaped grip part 39A (pulling part) into which the operator inserts his / her finger. The rotation restriction mechanism 31 restricts the rotation of the motor cover 9 to the closed position by inserting one end of the rod member 34 into the enlarged part 32C.

[0057] That is, the motor cover 9 is restricted from further rotating to the closed position by one end of the rod member 34 abutting against the abutment portion 32D which is the side edge of the expanded portion 32C. The wire 39 is used when one end of the rod member 34 is pulled up from the expanded portion 32C past the abutment portion 32D to the straight portion 32B. That is, by guiding one end of the rod member 34 to the straight portion 32B with the wire 39, the restriction by the rotation restriction mechanism 31 can be released. This allows the motor cover 9 to be rotated from the open position to the closed position.

[0058] Here, as shown in FIG. 11, the guide rail 32 is attached to the left side plate 16B of the battery bracket 16. As a result, the rotation restriction mechanism 31 is arranged biased to one side in the width direction in the space (engine room) surrounded by the motor cover 9. That is, the rotation restriction mechanism 31 is arranged biased to the right side in the left-right direction, which is the vehicle width direction. Therefore, when the motor cover 9 is opened, a continuous wide maintenance opening can be secured. Also, by making the rotation restriction mechanism 31 not to be located above the engine 7 that is extended in the width direction, the rotation restriction mechanism 31 can be prevented from becoming an obstacle during maintenance. However, in this case, if the rotation restriction mechanism 31 is configured to support the weight of the motor cover 9 when it is opened, the center of gravity position of the motor cover 9 and the position that supports the motor cover 9 are misaligned, causing a twisting load to be generated on the rotation restriction mechanism 31. Similarly, a twisting load is also generated on the motor cover 9. Therefore, in the embodiment, a stopper mechanism 29 (rubber stopper 23) that supports the weight of the entire prime mover cover 9 and its associated components (e.g., the driver's seat 10) when the prime mover cover 9 is opened is provided on the rotation center O side of the prime mover cover 9 and at a position corresponding to the center in the width direction.

[0059] When the motor cover 9 is opened from the closed position to the open position, the motor cover 9 rotates integrally with members (cover side members) such as the driver's seat 10 mounted on the motor cover 9. In this case, when the center of gravity G of the motor cover 9 and the entirety of the members rotating together with the motor cover 9 (hereinafter referred to as the entire motor cover 9) passes through a vertical (perpendicular) imaginary line AA that passes through the rotation center O of the motor cover 9 and extends in the up-down direction, the motor cover 9 opens to the open position due to its own weight. In the embodiment, as shown in Figs. 7 and 8, the rotation angle θ1 at which the center of gravity G of the entire motor cover 9 passes through the imaginary line AA is set to, for example, 50°.

[0060] 7 and 8 show the state of the rotation restriction mechanism 31 and the connecting device 21 (hinge mechanism 28, stopper mechanism 29) immediately after the center of gravity G of the entire motor cover 9 passes over the vertical imaginary line AA that passes through the rotation center O of the motor cover 9 and extends in the up-down direction. At this time, the rubber stopper 23 on the vehicle body side bracket 22 side and the abutment piece 24E of the cover side bracket 24 of the stopper mechanism 29 start to abut. At the same time, one end of the rod member 34 of the rotation restriction mechanism 31 enters the enlarged portion 32C of the guide hole 32A. As a result, the movement range of the motor cover 9 is restricted to a range in which one end of the rod member 34 can move within the enlarged portion 32C. That is, the motor cover 9 can be rotated toward the open position side within the range corresponding to the enlarged portion 32C, but is restricted from being rotated toward the closed position side beyond the range corresponding to the enlarged portion 32C.

[0061] 9 and 10 show the state of the rotation restriction mechanism 31 and the connecting device 21 (hinge mechanism 28, stopper mechanism 29) when the motor cover 9 is in the open position (maximum open position). At this time, the load of the entire weight of the motor cover 9 is applied to the rubber stopper 23 on the vehicle body side bracket 22 side from the abutting piece 24E of the cover side bracket 24 of the stopper mechanism 29, and the rubber stopper 23 is compressed and deformed. As a result, the load of the weight of the motor cover 9 is reduced by the rubber stopper 23. Also, in the rotation restriction mechanism 31, one end of the rod member 34 moves within the enlarged portion 32C of the guide hole 32A and stops halfway through the enlarged portion 32C. Therefore, almost no load due to the weight of the motor cover 9 is applied to the rod member 34 and the guide rail 32 (guide hole 32A).

[0062] Here, in the hydraulic excavator 1 (i.e., mini-excavator) as in the embodiment, the maintenance work performed by opening the prime mover cover 9 includes the replacement of the battery 17. For this reason, assuming that the rotation angle when the prime mover cover 9 is in the closed position is set as a reference (0°), it is preferable that the rotation angle of the prime mover cover 9 in the open position is set to a minimum rotation angle (e.g., 60°) or more at which an operator can replace the battery 17. In the embodiment, as shown in Figs. 9 and 10, the maximum rotation angle θ2 of the prime mover cover 9 is set to, for example, 80°. The maximum rotation angle θ2 can be set, for example, as the rotation angle of the prime mover cover 9 when the block stopper 22E serving as a rigid stopper comes into contact with the U-shaped contact body 24D. Note that Figures 13 and 15 show the coupling device 21 (hinge mechanism 28, stopper mechanism 29) when the motor cover 9 is in the closed position, and Figures 14 and 16 show the coupling device 21 (hinge mechanism 28, stopper mechanism 29) when the motor cover 9 is in the maximum closed position.

[0063] When the motor cover 9 is in the open position, a force in the opening direction is generated on the motor cover 9 due to the weight of the entire motor cover 9. Therefore, in the stopper mechanism 29, the rubber stopper 23 comes into contact with the abutment piece 24E of the cover side bracket 24, and further, the rubber stopper 23 is compressed and deformed due to the load due to the weight of the entire motor cover 9. Furthermore, when the motor cover 9 is in the open position, in the rotation restriction mechanism 31, one end of the rod member 34 is located in the enlarged portion 32C of the guide hole 32A. This keeps the motor cover 9 in the open state. At this time, a force is applied to the motor cover 9 by the reaction force of the rubber stopper 23 to return the motor cover 9 in the closing direction. Therefore, when the motor cover 9 is in the open position and no external force is applied to the motor cover 9, the rotation angle of the motor cover 9 is about 70°, which is smaller than the maximum angle of 80°.

[0064] Thus, according to the embodiment, the hydraulic excavator 1 as a construction machine includes the revolving frame 5 as a vehicle body component, the engine 7 as a prime mover, the prime mover cover 9, and a rotation restricting mechanism 31. The revolving frame 5 has the working device 4 attached to the front side. The engine 7 is attached to the revolving frame 5. The prime mover cover 9 has a driver's seat 10 provided at an upper portion and at a position corresponding to the center in the width direction. The prime mover cover 9 is attached to the revolving frame 5 (counterweight 5C) so as to be vertically rotatable between a closed position (e.g., Figs. 1, 3, 13, 15) in which the engine 7 is covered from above and an open position (e.g., Figs. 7 to 10, 14, 16) in which the engine 7 is exposed to the outside. The rotation restricting mechanism 31 restricts the prime mover cover 9 from rotating toward the closed position when the prime mover cover 9 is in the open position.

[0065] In addition, according to the embodiment, the revolving frame 5 (counterweight 5C) is provided with a stopper mechanism 29 (e.g., block stopper 22E, rubber stopper 23) at a position on the rotation center O side of the prime mover cover 9 and corresponding to the center in the width direction of the prime mover cover 9. That is, the stopper mechanism 29 is provided on the rotation center O side (the rear side opposite the maintenance opening) in the front-rear direction of the prime mover cover 9 and at a position corresponding to the center in the left-right direction of the prime mover cover 9. In addition, the center in the left-right direction of the prime mover cover 9 corresponds to the position where the driver's seat 10 is provided. That is, the stopper mechanism 29 is disposed at a position overlapping with the driver's seat 10 in the width direction of the prime mover cover 9 (the left-right direction of the upper revolving body 3).

[0066] The stopper mechanism 29 abuts against a member on the motor cover 9 side (the abutment piece 24E and the abutment body 24D of the cover-side bracket 24), thereby restricting the motor cover 9 from rotating beyond a predetermined opening angle. The stopper mechanism 29 also has a rubber stopper 23 that elastically abuts against a member on the motor cover 9 side (the abutment piece 24E of the cover-side bracket 24). The rubber stopper 23 allows the motor cover 9 to rotate up to the predetermined opening angle while abutting against the member on the motor cover 9 side (the abutment piece 24E of the cover-side bracket 24) from an opening angle smaller than the predetermined opening angle.

[0067] The predetermined opening angle is set to an angle at which the center of gravity G of the entire "motor cover 9" and "members that rotate together with the motor cover 9, including the driver's seat 10" exceeds a vertical (perpendicular) imaginary line AA that passes through the rotation center O of the motor cover 9 and extends in the up-down direction. That is, the predetermined opening angle is set to a rotation angle θ2 shown in Fig. 9 (more specifically, an angle slightly returned from this angle due to the reaction force of the rubber stopper 23) that is larger than the rotation angle θ1 shown in Fig. 7 (the rotation angle θ1 when the center of gravity G of the entire motor cover 9 exceeds the imaginary line AA).

[0068] The rotation restriction mechanism 31 includes a guide rail 32 and a rod member 34. The guide rail 32 has a guide hole 32A extending in a predetermined direction (specifically, the front-rear direction which is the longitudinal direction of the guide rail 32), and is provided on the revolving frame 5 side (more specifically, the battery bracket 16 fixed to the revolving frame 5). One end (front end, tip) of the rod member 34 is movably attached to the guide hole 32A of the guide rail 32, and the other end (rear end, base end) is rotatably attached to the prime mover cover 9 (more specifically, the rod support member 33 fixed to the prime mover cover 9).

[0069] As shown in FIG. 5, the "one end" and the "other end" of the rod member 34 are not limited to the "end" of the rod member 34, but correspond to a portion having a certain width including the "end" (one end, the other end, one end side, the other end side). As shown in FIG. 9 and FIG. 10, when the motor cover 9 is in the open position (more specifically, the maximum rotation angle θ2), one end of the rod member 34 is separated from the edge 32E of the guide hole 32A in a predetermined direction (longitudinal direction, front-rear direction) via a gap. In other words, when the rotation of the motor cover 9 is restricted by the stopper mechanism 29, one end of the rod member 34 is separated from the edge 32E of the guide hole 32A in a predetermined direction (the direction in which the guide hole 32A extends) via a gap.

[0070] 3 and 5, the guide hole 32A of the guide rail 32 is provided with an abutment portion 32D that abuts against one end of the rod member 34 to restrict the motor cover 9 from rotating toward the closed position. As shown in Fig. 7 and 8, the abutment portion 32D corresponds to the position of one end of the rod member 34 when the center of gravity G of the entire "motor cover 9" and "members that rotate together with the motor cover 9, including the driver's seat 10" passes through an imaginary line AA passing through the rotation center O of the motor cover 9.

[0071] The hydraulic excavator 1 according to the embodiment has the configuration described above. Next, its operation will be described.

[0072] The operator boards on the floor 11 and sits in the driver's seat 10. The operator seated in the driver's seat 10 can operate the travel lever 13 on the lever stand 12 to travel the lower traveling body 2. On the other hand, the operator can operate the work lever 14 to rotate the upper rotating body 3 and turn the work device 4 to perform work such as excavating soil and sand.

[0073] Also, for example, when performing maintenance on the engine 7, the prime mover cover 9 is opened from the closed position. Specifically, by operating the opening / closing lever 9F, which serves as a locking mechanism for the prime mover cover 9, the prime mover cover 9 is unlocked from the rotating frame 5, and the prime mover cover 9 is lifted in the opening direction. At this time, the prime mover cover 9 is opened upward with the first support shaft 25 and the second support shaft 26 of the hinge mechanism 28 as the rotation center. Then, when the prime mover cover 9 exceeds a predetermined rotation angle, one end of the rod member 34 of the rotation restriction mechanism 31 enters the enlarged portion 32C of the guide hole 32A. As a result, the prime mover cover 9 is held in an open state by the rotation restriction mechanism 31 within a range in which one end of the rod member 34 can move within the enlarged portion 32C of the guide hole 32A. The predetermined rotation angle is set, for example, to an angle at which the center of gravity G of the entire prime mover cover 9 exceeds a vertical imaginary line AA that passes through the rotation center O of the prime mover cover 9 and extends in the up-down direction.

[0074] That is, when the operator rotates the prime mover cover 9 from the closed position to the open position, one end of the rod member 34 is guided in the straight portion 32B of the guide hole 32A from one side (the front side, the working device 4 side) to the other side (the rear side, the counterweight 5C side) in accordance with this rotation. Then, when the opening operation of the prime mover cover 9 is continued, one end of the rod member 34 moves to the enlarged portion 32C of the guide hole 32A. That is, as shown in Figs. 7 and 8, the rotation angle of the prime mover cover 9 becomes θ1 (=50°), and the center of gravity G of the entire prime mover cover 9 crosses the imaginary line AA. As a result, the prime mover cover 9 is in an "open holding state" in which the open state is held by the rotation restriction mechanism 31.

[0075] 9 and 10 show the state where the motor cover 9 is in the maximum open position, that is, the state where the rotation angle of the motor cover 9 is θ2 (=80°). As shown in FIG. 9 and FIG. 10, even at this time, one end of the rod member 34 can move within the enlarged portion 32C of the guide hole 32A and does not come into contact (clash) with the longitudinal (front-rear) edge 32E of the guide hole 32A. When the motor cover 9 is in the open position, even if a force in the closing direction is applied to the motor cover 9 due to an external force such as wind, the one end of the rod member 34 comes into contact with the contact portion 32D of the enlarged portion 32C. As a result, the restriction by the rotation restriction mechanism 31 is not released, and the motor cover 9 can be maintained in the open state.

[0076] When opening the motor cover 9 from the closed position, a large force corresponding to the weight of the entire motor cover 9 is required until the center of gravity G of the entire motor cover 9 passes over the imaginary vertical line AA passing through the rotation center O. However, once this point is exceeded, the weight of the entire motor cover 9 acts in the direction of opening the motor cover 9. As a result, an auxiliary force in the opening direction due to the weight of the entire motor cover 9 is applied to the motor cover 9, making it possible to easily open the motor cover 9 to the open position.

[0077] At this time, one end of the rod member 34 of the rotation restriction mechanism 31 enters the enlarged portion 32C of the guide hole 32A in accordance with the opening movement of the motor cover 9, and passes the abutment portion 32D, dropping below the enlarged portion 32C. As a result, the rotation restriction mechanism 31 automatically enters the "open holding state." In addition, even if the hand is released from the motor cover 9 before the abutment piece 24E of the cover side bracket 24 abuts against the rubber stopper 23 after the center of gravity G of the entire motor cover 9 passes the imaginary line AA, the rubber stopper 23 can cushion the momentum of the motor cover 9. This can prevent the block stopper 22E of the vehicle side bracket 22 and the abutment body 24D of the cover side bracket 24 from colliding with a strong force. In addition, the load applied to the rotation restriction mechanism 31 can also be reduced.

[0078] After the necessary work such as the maintenance of the engine 7 is completed, the prime mover cover 9 is returned from the open position to the closed position. At this time, the operator pulls upward the gripping portion 39A of the wire 39 visible from the opening of the prime mover cover 9 with one hand. This allows one end of the rod member 34 to be pulled up to the upper side of the enlarged portion 32C, and the restriction by the rotation restriction mechanism 31 can be released. At this time, in accordance with this movement, the prime mover cover 9 is lifted in the closing direction with the other hand. Then, when the rotation angle of the prime mover cover 9 becomes smaller than θ1 (=50°), the restriction by the rotation restriction mechanism 31 is completely released. Thereafter, the hand is released from the wire 39 and the prime mover cover 9 is closed, so that the prime mover cover 9 can finally be brought to the closed position.

[0079] Thus, in the embodiment, in order to reduce the load applied to the rotation restriction mechanism 31 when the motor cover 9 is opened, the stopper mechanism 29 having the rubber stopper 23 is provided. As shown in Figs. 8, 9, 13 and 16, when the motor cover 9 is in the maximum open position (θ2=80°), the rubber stopper 23 of the stopper mechanism 29 is compressed and deformed by the weight of the entire motor cover 9. At this time, in the rotation restriction mechanism 31, one end of the rod member 34 does not come into contact (clash) with the edge 32E in the longitudinal direction (front-rear direction) of the guide hole 32A. This makes it possible to reduce the load applied to the rotation restriction mechanism 31. In addition, the rubber stopper 23 that supports the entire motor cover 9 is provided at a position corresponding to the center of the motor cover 9 in the width direction. Therefore, it is also possible to reduce the twisting of the motor cover 9 when the motor cover 9 is in the open position.

[0080] As described above, according to the embodiment, the stopper mechanism 29 is provided on the revolving frame 5 (counterweight 5C) which is a vehicle body component. The stopper mechanism 29 (rubber stopper 23, block stopper 22E) abuts against the components on the motor cover 9 side (the abutment piece 24E and the abutment body 24D of the cover side bracket 24), thereby restricting the motor cover 9 from rotating beyond a predetermined opening angle. For this reason, the rotation of the motor cover 9 in the opening direction is restricted by the stopper mechanism 29 provided separately from the rotation restriction mechanism 31. That is, the weight of the motor cover 9 and the components associated with the motor cover 9 (driver's seat 10, etc.) can be supported by the stopper mechanism 29. This makes it possible to suppress deformation and damage of the rotation restriction mechanism 31. As a result, since the rotation restriction mechanism 31 does not need to be configured to be strong, the size of the rotation restriction mechanism 31 can be suppressed.

[0081] Moreover, the stopper mechanism 29 (rubber stopper 23, block stopper 22E) that comes into contact with the components on the motor cover 9 side (contact piece 24E and contact body 24D of cover-side bracket 24) is provided on the rotation center O side of the motor cover 9 and at a position corresponding to the center in the width direction. Therefore, for example, compared to a configuration in which the stopper mechanism is provided at a position away from the position corresponding to the center in the width direction of the motor cover, it is possible to suppress twisting of the motor cover 9 when the motor cover 9 is in the open position.

[0082] 9 and 10, when the motor cover 9 is in the open position (i.e., when the rotation of the motor cover 9 is restricted by the stopper mechanism 29), one end of the rod member 34 of the rotation restricting mechanism 31 is separated from the edge 32E of the guide hole 32A of the guide rail 32 via a gap. This makes it possible to prevent the weight of the motor cover 9 and the members (such as the driver's seat 10) associated with the motor cover 9 from being applied from the one end of the rod member 34 to the edge 32E of the guide hole 32A. This also makes it possible to prevent deformation and damage to the rotation restricting mechanism 31 and to prevent the rotation restricting mechanism 31 from becoming large.

[0083] According to the embodiment, the stopper mechanism 29 has a rubber stopper 23 that elastically abuts against a member on the motor cover 9 side (the abutment piece 24E of the cover side bracket 24). Therefore, the motor cover 9 can be elastically held in the open position. Also, when the motor cover 9 opens forcefully in the open direction, the abutment (crash) between the member on the motor cover 9 side (for example, the U-shaped abutment body 24D of the cover side bracket 24) and the stopper mechanism 29 (the block stopper 22E of the vehicle body side bracket 22) can be buffered. Furthermore, the rubber stopper 23 allows the motor cover 9 to rotate to a predetermined opening angle while abutting against the motor cover 9 (the abutment piece 24E of the cover side bracket 24) from an opening angle smaller than a predetermined opening angle. Therefore, the positioning and fixing work of the open position of the motor cover 9 can be easily performed.

[0084] According to the embodiment, the predetermined opening angle at which the motor cover 9 is held in the open position is set to an angle at which the center of gravity G of the entire motor cover 9 and the members rotating together with the motor cover 9 exceeds the rotation center O of the motor cover 9 (more specifically, a vertical imaginary line AA that passes through the rotation center O and extends in the up-down direction). Therefore, when the motor cover 9 is in the open position, the weight of the motor cover 9 and the members rotating together with the motor cover 9 is applied as a force in a direction that brings the members on the motor cover 9 side (the abutment piece 24E of the cover-side bracket 24) and the stopper mechanism 29 (the rubber stopper 23) into contact with each other. Therefore, the weight of the motor cover 9 and the members rotating together with the motor cover 9 can hold the motor cover 9 in the open position.

[0085] According to the embodiment, the guide hole 32A of the guide rail 32 is provided with an abutment portion 32D that restricts the motor cover 9 from rotating toward the closed position by abutting against one end of the rod member 34. Therefore, the abutment between the one end of the rod member 34 and the abutment portion 32D of the guide hole 32A can restrict the motor cover 9 from rotating further toward the closed position.

[0086] According to the embodiment, the abutment portion 32D corresponds to the position of one end of the rod member 34 when the center of gravity G of the entire motor cover 9 and the members rotating together with the motor cover 9 exceeds the rotation center O of the motor cover 9 (more specifically, a vertical imaginary line AA passing through the rotation center O and extending in the up-down direction). Therefore, if the motor cover 9 is opened to a position where one end of the rod member 34 exceeds the abutment portion 32D, the motor cover 9 can be opened to the open position (the position held by the stopper mechanism 29) by the weight of the motor cover 9 and the members associated with the motor cover 9, and the rotation of the motor cover 9 to the closed position can be restricted.

[0087] In the embodiment, the counterweight-integrated revolving frame 5 has been described as an example of a vehicle body component that constitutes the vehicle body of the hydraulic excavator 1. However, the present invention is not limited to this, and for example, the revolving frame and the counterweight may be separate bodies, and the counterweight that is separate from the revolving frame may be fixed to the revolving frame. In this case, the revolving frame and the counterweight correspond to vehicle body components, i.e., vehicle body components to which the working device is attached and to which the prime mover cover is attached.

[0088] That is, the prime mover cover can be attached to the revolving frame to which the working device is attached directly or via other members (counterweight, building cover, prime mover cover support member, etc.). In the case where the prime mover cover is directly attached to the revolving frame, the revolving frame corresponds to the vehicle body constituent member to which the working device and the prime mover cover are attached. In the case where the prime mover cover is attached to the revolving frame via other members, the revolving frame and other members (counterweight, building cover, prime mover cover support member, etc.) correspond to the vehicle body constituent member to which the working device and the prime mover cover are attached.

[0089] In the embodiment, an example has been described in which the stopper mechanism 29 (rubber stopper 23) is provided on the revolving frame 5 (counterweight 5C) which is a vehicle body constituent member. However, this is not limiting, and the stopper mechanism (rubber stopper) may be provided on the prime mover cover. In this case, the stopper mechanism abuts against the vehicle body constituent member to restrict the prime mover cover from rotating beyond a predetermined opening angle. That is, the stopper mechanism can be provided on either the vehicle body constituent member or the prime mover cover. The stopper mechanism abuts against the other of the vehicle body constituent member or the prime mover cover to restrict the prime mover cover from rotating beyond the predetermined opening angle.

[0090] In the embodiment, the hydraulic excavator 1 equipped with a swing-type working implement 4 has been described as an example. However, the present invention is not limited to this, and can be applied to hydraulic excavators equipped with other types of working implements (front implements), such as hydraulic excavators equipped with a mono-boom type working implement and hydraulic excavators equipped with an offset type working implement. In addition, although the embodiment has been described as an example in which the working implement of the working implement 4 is the bucket 4D, a working implement equipped with another working implement, such as a crusher, may also be used.

[0091] In the embodiment, the hydraulic excavator 1 equipped with the roll bar 15 has been described as an example. However, the present invention is not limited to this, and for example, a hydraulic excavator with a cab or a hydraulic excavator with a canopy may be used.

[0092] In the embodiment, a small hydraulic excavator 1 has been described as an example, but the present invention may be applied to a larger hydraulic excavator, for example. Also, although the vehicle body has been described as being composed of a lower traveling body 2 and an upper rotating body 3, the vehicle body may not have a rotating body (for example, an articulated vehicle body in which a front vehicle body having front wheels and a rear vehicle body having rear wheels are flexibly connected via a connecting shaft).

[0093] In the embodiment, the hydraulic excavator 1 has been taken as an example of the construction machine, but the present invention is not limited to this and can be widely applied to various types of construction machines such as wheel loaders. [Explanation of symbols]

[0094] 1. Hydraulic excavator (construction machinery) 2 Undercarriage (car body) 3 Upper rotating body (car body) 4 Work equipment 5 Swing frame (body component) 7 Engine (prime mover) 9 Engine cover 10 Driver's seat 21 Coupling device 23 Rubber stopper 29 Stopper mechanism 31 Rotation control mechanism 32 Guide rail 32A Guide hole 32D Contact part 32E Edge 34 Rod member G Overall center of gravity O Rotation center

Claims

1. A vehicle body component having a working device attached thereto; A prime mover attached to the vehicle body structural member; and an engine cover attached to the vehicle body constituent member so as to be rotatable in a vertical direction between a closed position that covers the engine from above and an open position that exposes the engine to the outside, the engine cover including a driver's seat provided at an upper portion and a position corresponding to a center in a width direction; a rotation restricting mechanism that restricts the motor cover from rotating toward the closed position when the motor cover is in the open position, A construction machine characterized in that a stopper mechanism is provided on one of the vehicle body component or the motor cover at a position toward the rotation center of the motor cover and corresponding to the center in the width direction, which abuts against the other of the vehicle body component or the motor cover to prevent the motor cover from rotating beyond a predetermined opening angle.

2. The rotation restriction mechanism includes: a guide rail having a guide hole extending in a predetermined direction and provided on the vehicle body component; a rod member having one end movably attached to the guide hole of the guide rail and the other end rotatably attached to the prime mover cover, 2. The construction machine according to claim 1, wherein when the rotation of the prime mover cover is restricted by the stopper mechanism, one end of the rod member is separated from the edge of the guide hole in the specified direction via a gap.

3. the stopper mechanism has a rubber stopper that allows the prime mover cover to rotate to the predetermined opening angle while abutting against the other cover from an opening angle smaller than the predetermined opening angle, 2. The construction machine according to claim 1 .

4. 2. The construction machine according to claim 1, wherein the predetermined opening angle is set at an angle at which the center of gravity of the entire motor cover and members that rotate together with the motor cover, including the driver's seat, exceeds the center of rotation of the motor cover.

5. 3. A construction machine as described in claim 2, characterized in that the guide hole of the guide rail is provided with an abutment portion that abuts against the one end of the rod member to restrict the rotation of the prime mover cover toward the closed position.

6. The construction machine according to claim 5, characterized in that the abutment portion corresponds to the position of the one end of the rod member when the overall center of gravity of the motor cover and the members that rotate together with the motor cover, including the driver's seat, exceeds the rotation center of the motor cover.

Images