Front guard and working vehicle

Abstract

To provide a front guard and a working vehicle capable of restraining a flexible member from being damaged when the flexible member possessed by a working device comes into contact with the front guard, while excellently securing visibility of an operator.SOLUTION: The front guard 50 is arranged between an operator cabin 25 on which an operator rides and the work device 30, and covers a front surface of the cabin. In an upper region of the front guard 50, a plurality of plate-like members 54 are arranged so as to extend in a vertical direction, have a rectangular cross section, and have long sides of the rectangular shape radially around an eye point 70 of the operator seated in the operator cabin 25. In a facing region 57 facing the work device 30 in a lower region of the front guard 50, a plurality of rod-shaped members 58 extending in the vertical direction and having a circular cross section are arranged.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a front guard and a work vehicle. [Background technology]

[0002] BACKGROUND ART Some work vehicles such as hydraulic excavators are provided with a front guard in front of the cabin in which the operator sits to protect the operator from flying objects and the like.

[0003] For example, Patent Document 1 describes a front guard in which multiple first plate members are arranged radially around the viewpoint of the driver sitting in the driver's seat so as not to impair the driver's visibility due to the front guard.

[0004] Furthermore, Patent Document 2 describes a hydraulic excavator provided with a protective guard (front guard) that provides a hose relief opening at a position that interferes with a slack portion of a hydraulic hose that connects a cylinder or the like of a front device to a control valve. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5355831 [Patent Document 2] Patent No. 4317100 Summary of the Invention [Problem to be solved by the invention]

[0006] The first plate-shaped member of the front guard described in Patent Document 1 has a square cross section. Therefore, hydraulic hoses provided on an attachment of the work vehicle may come into contact with the corners of the first plate-shaped member, causing wear or the like in the hydraulic hoses, which may result in damage to the hydraulic hoses.

[0007] In addition, in Patent Document 2, although the provision of a hose relief opening prevents contact between the front guard and the hydraulic hose, the front guard cannot protect the cabin from flying objects. Also, in Patent Document 2, a removable opening blocking guard can be provided to block the hose relief opening, but with this configuration, as in Patent Document 1, the opening blocking guard can come into contact with the hydraulic hose, potentially damaging the hydraulic hose.

[0008] As described above, Patent Documents 1 and 2 do not prevent flexible members such as hydraulic hoses from coming into contact with the front guard and being damaged.

[0009] Therefore, an object of the present invention is to provide a front guard and a work vehicle that can ensure good visibility for the operator while preventing flexible members provided on the work equipment from coming into contact with the front guard and causing damage to the flexible members. [Means for solving the problem]

[0010] The front guard of the first aspect of the present invention is a front guard that is arranged between the cabin in which the operator sits and the work equipment that performs a specified task, and covers the front of the cabin, and in the upper region of the front guard, a plurality of plate-shaped members are arranged that extend in the vertical direction and have a rectangular cross section, with the long sides of the rectangle radiating out from the eye position of the operator seated in the cabin, and in the region of the lower region of the front guard facing the work equipment, a plurality of rod-shaped members are arranged that extend in the vertical direction and have a circular cross section.

[0011] According to this configuration, multiple plate-shaped members are arranged in the upper region of the front guard so as to radiate from the position of the operator's eyes, or so-called eye point, thereby preventing the front guard from impairing the operator's visibility. Furthermore, multiple rod-shaped members with circular cross sections are arranged in the lower region of the front guard, where components of the work equipment, such as hydraulic hoses, may come into contact. Because the rod-shaped members have circular cross sections and no corners, the work equipment is less likely to be damaged even if they come into contact with a flexible member provided in the work equipment. Thus, according to this configuration, the operator's visibility is maintained good while preventing damage to the flexible member provided in the work equipment due to contact with the front guard.

[0012] A second aspect of the front guard is the front guard of the first aspect, wherein the rod-shaped member includes a recessed portion recessed toward the cabin. This configuration increases the distance between the rod-shaped member and the working device, thereby reducing contact between the rod-shaped member and a flexible member of the working device. This configuration reduces damage to the hydraulic hose due to contact with the rod-shaped member.

[0013] A third aspect of the front guard may be the front guard of the first or second aspect, further comprising a frame that surrounds the front guard, and the lower ends of the rod-shaped members may be welded to the front surface of the frame that constitutes the front guard. By connecting the rod-shaped members to the front guard by welding, the rod-shaped members are more resistant to frontal impacts than, for example, when fastened with bolts. This improves the durability of the front guard and the protection of the driver.

[0014] A fourth aspect of the front guard is the front guard of any one of the first to third aspects, and includes a frame that surrounds the front guard, and the upper ends of the rod-shaped members are connected to beams that extend laterally of the frame that constitute the front guard, and the lower ends of the rod-shaped members are connected to a lower part of the frame. With this configuration, the rod-shaped members have a fixed-end beam structure, which increases their strength and makes them more resistant to frontal impacts. With this configuration, damage to the rod-shaped members due to contact with hydraulic hoses can be reduced.

[0015] A fifth aspect of the front guard is the front guard of the second aspect, wherein the working device has a flexible member, and the recessed portion is formed so that the rod-shaped member and the flexible member do not come into contact with each other. This configuration can prevent damage to the flexible member of the working device.

[0016] In a sixth aspect of the front guard, in the fifth aspect, the flexible member may be a hydraulic hose that supplies hydraulic oil. With this configuration, damage to the hydraulic hose of the working device can be suppressed.

[0017] The work vehicle of the seventh embodiment comprises a cabin in which an operator rides, a work device for performing a specified task, and a front guard that is arranged between the cabin and the work device and covers the front of the cabin, and in the upper region of the front guard, a plurality of plate-shaped members are arranged that extend in the vertical direction and have a rectangular cross section, with the long sides of the rectangle radiating out from the eye position of the operator seated in the cabin, and in the area facing the work device in the lower region of the front guard, a plurality of rod-shaped members that extend in the vertical direction and have a circular cross section are arranged. [Effects of the Invention]

[0018] According to the present invention, it is possible to ensure good visibility for the operator while preventing a flexible member provided in a work implement from coming into contact with the front guard and causing damage to the flexible member. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a front perspective view of a hydraulic excavator according to an embodiment. [Figure 2] FIG. 2 is a front perspective view of the front guard according to the embodiment. [Figure 3] FIG. 2 is a side view of the front guard according to the embodiment. [Figure 4] FIG. 2 is a cross-sectional view of the upper region of the front guard of the embodiment. [Figure 5] FIG. 4 is an enlarged view of a facing region in the front guard of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the embodiment described below shows an example of how the present invention can be implemented, and the present invention is not limited to the specific configuration described below. When implementing the present invention, a specific configuration corresponding to the embodiment may be appropriately adopted.

[0021] An example of the work vehicle of this embodiment is a hydraulic excavator 1. As shown in the front perspective view of Fig. 1, the hydraulic excavator 1 includes a lower traveling body 10 configured to be able to travel, an upper rotating body 20 provided above the lower traveling body 10 so as to be able to rotate horizontally, and a work device 30 provided in front of the upper rotating body 20 to perform a predetermined task. In the following description, the up-down direction of the hydraulic excavator 1 will also be referred to as the vertical direction, and the left-right direction of the hydraulic excavator 1 will also be referred to as the horizontal direction.

[0022] The undercarriage 10 is equipped with a pair of left and right crawler mechanisms 15, each having a drive wheel, a plurality of driven wheels, and tracks 14 wound around the wheels, on the left and right sides of the undercarriage frame 11. The left and right crawler mechanisms 15 have left and right traveling motors that rotate the drive wheels. The undercarriage 10 is configured to be able to travel in any direction and at any speed by controlling the rotation direction and rotation speed of the left and right traveling motors, respectively.

[0023] A blade 18 is provided at the front of the lower traveling body frame 11 so as to be able to swing up and down. The blade 18 is configured to be able to swing up and down by extending and contracting a blade cylinder 19 that is provided between the blade 18 and the lower traveling body frame 11.

[0024] A swivel mechanism is provided at the upper center of the lower travelling body frame 11. The upper swivel body 20 is provided to the lower travelling body frame 11 via the swivel mechanism so as to be able to rotate horizontally, and is configured to be able to rotate horizontally in the left and right directions relative to the lower travelling body 10 by operating a swivel motor (not shown) 8 in the forward or reverse direction.

[0025] The upper rotating body 20 has an upper rotating body frame 21 that is mounted on the lower running body frame 11 via a rotating mechanism so as to be able to rotate horizontally, and an operator cabin 25 that is mounted on the upper rotating body frame 21 and serves as a cabin for an operator. A main body head 22 that protrudes forward is provided at the front of the upper rotating body frame 21.

[0026] The work device 30 is provided on the front right side of the operator cabin 25. The work device 30 has a boom bracket 31 mounted on the main body head 22 so as to be swingable left and right about a vertical axis, a boom 32 mounted on the upper end of the boom bracket 31 so as to be swingable up and down (raise and lower), an arm 33 mounted on the tip of the boom 32 so as to be swingable up and down (bend and extend), and a bucket 34 mounted on the tip of the arm 33 so as to be swingable up and down. Furthermore, the work device 30 has a boom cylinder 36 mounted between the boom bracket 31 and the boom 32, an arm cylinder 37 mounted between the boom 32 and the arm 33, a bucket cylinder 38 mounted between the arm 33 and the bucket 34, and a link arm 39 mounted between the tip of the rod of the bucket cylinder 38 and the bucket 34.

[0027] The boom bracket 31 is configured to be swingable left and right relative to the main body head 22 (upper rotating body frame 21). The boom 32 is configured to be swingable up and down (raised and lowered) relative to the boom bracket 31 by extending and contracting a boom cylinder 36. The arm 33 is configured to be swingable up and down relative to the boom 32 by extending and contracting an arm cylinder 37. The bucket 34 is configured to be swingable up and down relative to the arm 33 via a link arm 39 by extending and contracting a bucket cylinder 38. These various cylinders are operated by hydraulic oil supplied from the upper rotating body 20 via a hydraulic hose 40, which is a flexible member provided in the working device 30.

[0028] Instead of the bucket 34, various attachments such as a breaker, crusher, cutter, and auger device can be attached to the ends of the arm 33 and link arm 39 so that they can swing up and down. When these attachments are attached, multiple connection ports are provided on both the left and right sides of the arm 33 to which hydraulic hoses 40 can be connected to supply hydraulic oil to the hydraulic actuators of the attachments.

[0029] The operator's cabin 25 is formed in a substantially rectangular box shape, forming an operation room inside where the operator can sit, and is provided with a cabin door 26 that can be opened and closed sideways on the left side. Inside the operator's cabin 25, there are provided an operator's seat where the operator can sit facing forward, various levers such as a travel operation lever, a swing operation lever, and a work operation lever, a display device, operation switches, pedals, etc.

[0030] The hydraulic excavator 1 of this embodiment is provided with a front guard 50 that is disposed in front of the operator cabin 25, that is, between the operator cabin 25 and the work implement 30, and that covers the front surface of the operator cabin 25.

[0031] Fig. 2 is a front perspective view of the front guard 50 of this embodiment. Fig. 3 is a side view of the front guard 50 of this embodiment, in which the facing region 57 described below is shown in cross section.

[0032] In this embodiment, a plurality of plate-like members 54 extending in the vertical direction and having a rectangular cross section are arranged in an upper region 52 of the front guard 50. Furthermore, a plurality of rod-like members 58 extending in the vertical direction and having a circular cross section are arranged in a region 57 (hereinafter referred to as the "facing region") facing the working device 30 in a lower region 56 of the front guard 50. The plate-like members 54 are so-called flat bars made of steel or iron such as SS400, and the rod-like members 58 are so-called round bars made of steel or iron such as SS400, but the plate-like members 54 and the rod-like members 58 are not limited to being made of steel or iron such as SS400 and may be made of other metals.

[0033] As an example, the front guard 50 has a rectangular frame 60 that forms the periphery of the front guard 50, and is provided with beams 62, 64 that extend laterally of the frame 60. The beams 62, 64 are provided so as to divide the frame 60 into three sections, upper and lower. Of these, as an example, the section above the beam 64 is defined as an upper region 52, and the section below the beam 64 is defined as a lower region 56. In the present embodiment, the beam 64 is formed by bolting beams 64A and 64B together in the vertical direction, and the upper front guard 50A located in the upper region 52 to the lower front guard 50B located in the lower region 56 can be removed.

[0034] Furthermore, mounting portions 66 are provided on the left and right sides of the frame 60 for mounting the front guard 50 to the front of the operator cabin 25. Holes are formed in the mounting portions 66 for inserting bolts 67, and the front guard 50 is mounted to the operator cabin 25 by the bolts 67.

[0035] In this embodiment, the right side of lower region 56 is a facing region 57. A plurality of rod-like members 58 are arranged in facing region 57. On the other hand, the left side of lower region 56 is a non-facing region 59, in which a plurality of plate-like members 54 are arranged.

[0036] As an example, nine plate-like members 54 are arranged in the horizontal direction in the upper region 52. As an example, five rod-like members 58 are arranged in the facing region 57 and four plate-like members 54 are arranged in the non-facing region 59 in the lower region 56. Note that in this embodiment, the numbers and horizontal positions of the plate-like members 54 and rod-like members 58 are the same in the upper region 52 and the lower region 56, but this is not limiting, and the numbers and horizontal positions of the plate-like members 54 and rod-like members 58 may differ between the upper region 52 and the lower region 56.

[0037] As shown in the cross-sectional view of FIG. 4 , the plate-like member 54 of this embodiment is arranged so that the long sides of the rectangle radiate from the eye position (hereinafter referred to as "eye point") 70 of the operator seated in the operator cabin 25. The eye point 70 is defined by various standards. For example, the eye point 70 is defined by "Earth-moving machinery - Operator's field of view" according to ISO5006:2017 and JIS A8311:2018, but the definition of the eye point 70 is not limited to these standards, and other standards may be used, or it may not be defined by a standard.

[0038] The dashed lines A connecting the eye point 70 to the plate-like members 54 in Figure 4 indicate the direction of the driver's line of sight. Even if the driver looks left or right in this way, because the plate-like members 54 are arranged radially, the long sides of the plate-like members 54 are unlikely to be in the driver's field of view, and only the short sides of the plate-like members 54 are in the driver's field of view. This prevents the front guard 50 from obstructing the driver's field of view.

[0039] As described above, the rod-shaped member 58 is disposed in the facing region 57 in the lower region 56 of the front guard 50. In this embodiment, there is a possibility that the facing region 57 may come into contact with components of the working device 30, such as the hydraulic hose 40, which is a flexible member. The rod-shaped member 58 disposed in the facing region 57 has a circular cross section with no corners, and therefore, even if the hydraulic hose 40 comes into contact with the rod-shaped member 58 when the working device 30 operates, the hydraulic hose 40 is unlikely to be damaged.

[0040] As described above, in the front guard 50 of this embodiment, a plurality of plate-like members 54 are arranged radially around the eye point 70 in the upper region 52, and a plurality of rod-like members 58 with circular cross sections are arranged in the opposing region 57 in the lower region 56. This ensures good visibility for the operator while preventing the hydraulic hose 40 from coming into contact with the front guard 50 and causing damage to the hydraulic hose 40.

[0041] Furthermore, it is preferable that the diameter of the rod-shaped member 58 is large. The reason for this is that the section modulus, which indicates the resistance to breaking of a cylinder, is proportional to the cube of the diameter, and therefore the rod-shaped member 58 is stronger as the diameter is large. Furthermore, the larger the diameter of the rod-shaped member 58, the larger the contact area with the hydraulic hose 40. Even if the rod-shaped member 58 and the hydraulic hose 40 come into contact, wear on the hydraulic hose 40 can be reduced, making the hydraulic hose 40 less likely to break. For this reason, it is preferable to arrange a smaller number of thick rod-shaped members 58 than to arrange a larger number of thin rod-shaped members 58. For example, the rod-shaped members 58 may have a diameter larger than the long side of the cross section of the plate-shaped members 54, and the number of the rod-shaped members 58 may be smaller than the number of plate-shaped members 54.

[0042] The diameter of the rod-shaped member 58 is, for example, approximately 6 mm to 42 mm. The diameter of the rod-shaped member 58 is 0.6 to 2.1 times the length of the long side of the plate-shaped member 54. The diameter of the rod-shaped member 58 is at least a diameter that allows the rod-shaped member 58 to pass a performance test for the operator protective structure. This performance test includes, for example, a Falling-Object Protective Structures (FOPS) test. The range of 6 mm to 42 mm is a range in which, by providing the rod-shaped member 58 in the facing region 57, the visibility area, which is the area visible to the operator, becomes larger than the obstructed area that obstructs the operator's view (visibility area > obstructed area).

[0043] Note that the rod-shaped member 58 is more likely to block the driver's view than the plate-shaped member 54 as described above. However, the opposing area 57 is near the feet of the driver seated in the operator cab 25, and generally, for the driver, the area beyond the opposing area 57 is outside the range of the excavation work by the hydraulic excavator 1. Therefore, during normal operation, the driver rarely visually recognizes the area beyond the opposing area 57. Thus, in the opposing area 57, it is not necessary to consider the driver's visibility, and it is sufficient if it is configured to ensure the driver's safety.

[0044] In addition, the rod-shaped member 58 of the present embodiment includes a recessed portion 72 having a concave shape that is recessed toward the direction of the operator cab 25, or in other words, toward the rear of the hydraulic excavator 1. The recessed portion 72 is formed so that the rod-shaped member 58 and the hydraulic hose 40 do not come into contact. The depth D of the recessed portion 72 is less than 40 mm (0 mm < D < 40 mm) with respect to the front surface of the front guard 50. Note that as long as there is a recess, contact between the hydraulic hose 40 and the rod-shaped member 58 can be suppressed, so at least the depth D should exceed 0 mm. On the other hand, the maximum value of the depth D is a value corresponding to the gap between the front guard 50 and the operator cab 25.

[0045] By forming the recessed portion 72 in the rod-shaped member 58, the distance between the front guard 50 and the hydraulic hose 40 becomes longer, preventing the hydraulic hose 40 from contacting the front guard 50 and suppressing damage to the hydraulic hose 40. Even if the hydraulic hose 40 contacts the recessed portion 72, since the distance between the rod-shaped member 58 and the hydraulic hose 40 is long, the frictional pressure between the rod-shaped member 58 and the hydraulic hose 40 can be reduced, suppressing damage to the hydraulic hose 40.

[0046] In addition, when a relatively large flying object hits the recessed portion 72 of the rod-shaped member 58, the flying object hits the recessed portion 72 at multiple locations rather than just one location, increasing the likelihood that the rod-shaped member 58 receives loads at multiple locations. This can further ensure the safety of the driver.

[0047] 5 is an enlarged view of the facing region 57. In this embodiment, the lower ends of the rod-shaped members 58 are welded to the front surface of the frame 60. More specifically, the vertical dimension of the front surface 61A of the horizontal plate 61 constituting the lower part of the frame 60 in this embodiment is larger than the longitudinal dimension, and the side surface 58A of the lower ends of the rod-shaped members 58 is welded to the front surface 61A of the horizontal plate 61. This provides greater resistance to frontal impacts than, for example, fixing the rod-shaped members 58 to the frame 60 with bolts, improving the durability of the front guard 50 and the protection of the operator. In addition, because the corners of the horizontal plate 61 are not located on the front side, contact between the corners of the horizontal plate 61 and the hydraulic hose 40 is prevented, thereby suppressing damage to the hydraulic hose 40.

[0048] On the other hand, the upper end of the rod-shaped member 58 is welded to the end face of the beam 64B. In this way, the upper end of the rod-shaped member 58 is connected to the beam 64B extending laterally of the frame 60, and the lower end of the rod-shaped member 58 is connected to the horizontal plate 61 of the frame 60. Since the rod-shaped member 58 has a fixed-end beam structure connected to the front guard 50 at two points, top and bottom, deflection is reduced compared to a cantilever beam structure. This reduces bending stress and improves the strength of the rod-shaped member 58, making the rod-shaped member 58 more resistant to frontal impacts.

[0049] Although the present invention has been described above using the above-mentioned embodiment, the technical scope of the present invention is not limited to the scope described in the above-mentioned embodiment. Various changes or improvements can be made to the above-mentioned embodiment without departing from the gist of the invention, and such changes or improvements are also included in the technical scope of the present invention.

[0050] In the above embodiment, a configuration has been described in which the hydraulic hose 40 provided on the working implement 30 faces the facing region 57 of the front guard 50, but the present invention is not limited to this, and the component of the working implement 30 facing the facing region 57 may be a flexible member other than the hydraulic hose 40, the boom 32, or the like. Note that flexible members other than the hydraulic hose 40 include, for example, electrical wiring, protective tubes for the hydraulic hose 40, and cable ties for securing the hydraulic hose 40 and the electrical wiring.

[0051] In the above embodiment, the working implement 30 is provided on the front right side of the operator cabin 25, but the present invention is not limited to this, and the working implement 30 may be provided on the front left side or the front center of the operator cabin 25. The facing area 57 of the front guard 50 is positioned according to the position of the working implement 30.

[0052] In the above embodiment, the rod-shaped members 58 are arranged vertically in the facing region 57 of the front guard 50, but the present invention is not limited to this, and the rod-shaped members 58 may be arranged horizontally in the facing region 57. In other words, the plate-shaped members 54 may be arranged vertically and the rod-shaped members 58 may be arranged horizontally. [Explanation of symbols]

[0053] 1. Hydraulic excavator 25 Operator Cabin (Cabin) 30 Work equipment 40 Hydraulic hose 50 Front guard 54 Plate-shaped member 58 Rod-shaped member 57 Opposing area 72 recess

Claims

1. A front guard that is arranged between a cabin in which an operator rides and a work device that performs a predetermined work, and covers the front of the cabin, In the upper region of the front guard, a plurality of plate-like members are arranged, each extending in the vertical direction and having a rectangular cross section, with the long sides of the rectangle radiating out from the eye position of the driver seated in the cabin as the center, A plurality of rod-shaped members extending in the vertical direction and having a circular cross section are arranged in a region of the lower region of the front guard facing the working device. Front guard.

2. The front guard according to claim 1 , wherein the rod-shaped member includes a recessed portion having a shape recessed toward the cabin.

3. a frame that forms the periphery of the front guard; 3. The front guard according to claim 1, wherein a lower end of the rod-shaped member is welded to the front surface of the frame.

4. a frame that forms the periphery of the front guard; The upper end of the rod-shaped member is connected to a beam extending laterally of the frame, 3. The front guard according to claim 1, wherein a lower end of the rod-shaped member is connected to a lower portion of the frame.

5. The working device has a movable member, The front guard according to claim 2 , wherein the recessed portion is formed so that the rod-shaped member and the flexible member do not come into contact with each other.

6. 6. The front guard according to claim 5, wherein the flexible member is a hydraulic hose for supplying hydraulic oil.

7. A cabin for the driver, a work device that performs a predetermined work; a front guard disposed between the cabin and the working device and covering a front surface of the cabin; In the upper region of the front guard, a plurality of plate-like members are arranged, each extending in the vertical direction and having a rectangular cross section, with the long sides of the rectangle radiating out from the eye position of the driver seated in the cabin as the center, A plurality of rod-shaped members extending in the vertical direction and having a circular cross section are arranged in a region of the lower region of the front guard facing the working device. Work vehicle.

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