CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority under 35 U. S. C. § 119 to Japanese Patent Application No. 2024-004605, filed Jan. 16, 2024. The contents of this application are incorporated herein by reference in their entirety.
BACKGROUND
Technical Field
The present invention relates to a work vehicle.
Discussion of the Background
Japanese Patent Application Laid-Open No. 2023-097643 discloses a work vehicle including a radiator fan provided in an engine compartment and a radiator provided on a member capable of being opened and closed with respect to the engine compartment. The work vehicle includes a feature that when a member provided with the radiator is opened, access to the engine room is facilitated.
SUMMARY OF THE INVENTION
In accordance with a first aspect of the present disclosure, a work vehicle includes a vehicle body frame, a support frame, a cooling fan, a first shroud, a heat exchanger, and a second shroud. The vehicle body frame includes an opening. The support frame rotatably connected to the vehicle body frame to be turned to a first position and a second position. The cooling fan provided on the vehicle body frame to face a part of the opening. The cooling fan includes blades configured to rotate around a fan rotational axis to generate cooling air, the fan rotational axis passing through the part of the opening, the blades defining a blade reachable region obtained by rotating the blades around the fan rotational axis. The first shroud is provided on the vehicle body frame between the blade reachable region and the vehicle body frame as viewed along the fan rotational axis. The first shroud has a first shape to cover a part of a side surface of the blade reachable region around the fan rotation axis. The heat exchanger is provided on the support frame to cover the part of the opening when the vehicle body frame is turned to the first position and to have the part of the opening uncovered when the vehicle body frame is turned to the second position. The heat exchanger has a first surface configured to receive the cooling air when the heat exchanger covers the part of the opening. The second shroud is provided on the support frame and includes a proximal end portion surrounding an outer periphery of the first surface of the heat exchanger, and a distal end portion extending from the proximal end portion and having a second shape to cover a remaining part of the side surface of the blade reachable region other than the part of the side surface, when the heat exchanger covers the part of the opening.
BRIEF DESCRIPTION OF DRAWINGS
A more complete appreciation of the present disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings.
FIG. 1 is an overall side view of a work vehicle.
FIG. 2 is a partial rear view of a work vehicle.
FIG. 3 is a partial rear view of the work vehicle when the bonnet cover is removed.
FIG. 4 is a view of the cooling fan, the first shroud, the second shroud, and the heat exchanger as viewed from the engine.
FIG. 5 is a perspective view showing the cooling fan, the first shroud, the second shroud, and the heat exchanger.
FIG. 6 is an enlarged view showing the cooling fan, the first shroud, the second shroud, and the heat exchanger.
FIG. 7 is a cross-sectional view taken along the line VII-VII′ in FIG. 6.
FIG. 8 is a view of the heat exchanger, the support frame, and the second shroud when they are disposed at the second position, as viewed from the rear.
FIG. 9 is a top view of the rear portion of the work vehicle when the upper cover is removed.
FIG. 10 is a front view showing the cooling fan, the first shroud, the second shroud, and the heat exchanger according to the second embodiment.
FIG. 11 is a top view showing the cooling fan, the first shroud, the second shroud, and the heat exchanger according to the second embodiment.
FIG. 12 is a left side view showing the cooling fan, the first shroud, the second shroud, and the heat exchanger according to the second embodiment.
DESCRIPTION OF THE EMBODIMENTS
Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Like reference numerals designate corresponding or identical elements throughout the several views.
First Embodiment
Referring to FIG. 1, a work vehicle 1 includes a vehicle body frame 2, a traveling device 3, an work device 4, and a cabin 5. The vehicle body frame 2 supports the traveling device 3, the work device 4, and the cabin 5. In the illustrated embodiment, the traveling device 3 is a crawler traveling device 3. However, the traveling device 3 is not limited to the crawler traveling device 3. The traveling device 3 may be, for example, a front wheel/rear wheel traveling device, or a traveling device 3 having a front wheel and a rear crawler. The work device 4 is provided with an implement (bucket) 41 at the distal end of the work device 4. The proximal end of the work device 4 is attached to the rear portion of the vehicle body frame 2. A work device 4 includes a pair of arms 42 for rotatably supporting the implement (bucket) 41 via a bucket rotational shaft 43. Each of the pair of arms 42 includes a lift link 44 and a boom 45. The lift link 44 is rotatable with respect to the vehicle body frame 2 about the first pivot pin 46. The boom 45 is rotatable about the second pivot pin 47 with respect to the lift link 44. The work device 4 further includes a boom cylinder 48 and at least one implements cylinder 49. Each boom cylinder 48 is rotatably connected to the vehicle body frame 2 and the boom 45, and operates the lift link 44 and the boom 45 to raise and lower the implement (bucket) 41. At least one implement cylinder 49 is configured to incline the implement (bucket) 41. The cabin 5 is attached to a front portion of the vehicle body frame 2. The work vehicle 1 includes a front door 51 provided at a front portion of the cabin 5, a driver's seat 52 provided inside the cabin 5, and an operating device (not illustrated).
In the illustrated embodiment, one of the pair of arms 42 is provided on the left side of the cabin 5. The other of the pair of arms 42 is provided on the right side of the cabin 5. Specifically, one of the boom cylinder 48 and the boom 45 is provided on the left side of the cabin 5. The other boom cylinder 48 and the other boom 45 are provided on the right side of the cabin 5. FIG. 1 shows the left side of the work vehicle 1. However, the left and right sides of the work vehicle 1 are substantially symmetrical.
The work vehicle 1 further includes an engine 6, a heat exchanger 7, a first shroud 10, a second shroud 15, and a cooling fan 20 provided at the vehicle body frame 2. The engine 6 is configured to provide driving force to the traveling device 3 and the work device 4. The heat exchanger 7 includes a radiator for cooling the cooling water of the engine 6. Preferably, the heat exchanger 7 includes an oil cooler for cooling a hydraulic fluid used in a hydraulic system (e.g., a boom cylinder and at least one implement cylinder 49) of the work vehicle 1. The cooling fan 20 is configured to generate cooling air for cooling the heat exchanger 7. The first shroud 10 and the second shroud 15 are configured to cover the outer periphery of the cooling fan 20 so as to efficiently send the cooling air to the heat exchanger 7. The engine 6, the heat exchanger 7, the first shroud 10, the second shroud 15, and the cooling fan 20 are provided between the pair of arms 42 in the left-right direction of the work vehicle 1. The engine 6, the heat exchanger 7, the first shroud 10, the second shroud 15, and the cooling fan 20 are provided between the boom cylinder 48 in the left-right direction of the work vehicle 1.
The work vehicle 1 further includes a bonnet cover 9. The bonnet cover 9 is provided at the rear end of the vehicle body frame 2 and covers the opening 82. FIG. 2 is a partial rear view of the periphery of the bonnet cover 9 of the work vehicle 1. Referring to FIG. 2, the bonnet cover 9 is swingable about a cover rotational axis Axc. In FIG. 2, since the hinge 91 for rotating the bonnet cover 9 exists on the back side of the bonnet cover 9, the hinge 91 is shown by a dotted line. The vehicle body frame 2 includes an upper cover 8 above and in front of the bonnet cover 9. The upper cover 8 is openable and closable.
FIG. 3 is a partial rear view of the work vehicle 1 when the bonnet cover 9 is removed. Referring to FIGS. 1 and 3, the vehicle body frame 2 includes a support wall 81 and has the opening 82 having the support wall 81 as a part of its outer periphery. The vehicle body frame 2 forming the opening 82 covers the front portion and the peripheral portion of the engine 6 and the cooling fan 20. FIG. 4 is a view of the cooling fan 20, the first shroud 10, the second shroud 15, and the heat exchanger 7 as viewed from the engine 6. FIG. 5 is a perspective view showing the cooling fan 20, the first shroud 10, the second shroud 15, and the heat exchanger 7. FIG. 6 is an enlarged view showing the cooling fan 20, the first shroud 10, the second shroud 15, and the heat exchanger 7. In FIGS. 3 and 4, the pair of arms 42 is not illustrated. Referring to FIGS. 3-5, the heat exchanger 7 includes a first surface 71 and a second surface 72 opposite to the first surface 71 in the thickness direction (air-flow direction) Dt. Referring to FIGS. 4 and 5, the second shroud 15 includes a proximal end portion 16 that covers the outer periphery of the first surface 71 of the heat exchanger 7, and a distal end portion 17 having a second shape that is a substantially arc shape when viewed from the thickness direction Dt. The second shape is a shape of the inner peripheral surface of the distal end portion 17 as viewed in the thickness direction Dt. The second shroud 15 has a tubular shape extending in the thickness direction Dt from the proximal end portion 16 to the distal end portion 17.
Referring to FIG. 3, the work vehicle 1 further includes a support frame 30 and a hinge 93. The support frame 30 supports the heat exchanger 7 and the first shroud 10 so that the distal end portion 17 and the second surface 72 are exposed. As shown in FIGS. 3, 5, and 6, the support frame 30 is a frame-shaped member that surrounds the outer peripheral surface of the heat exchanger 7 that connects the first surface 71 and the second surface 72. Referring to FIG. 3, the hinge 93 is provided on the support wall 81. The hinge 93 is connected to the support frame 30. The support frame 30 is supported by the hinge 93 so as to be rotatable about a hinge rotational axis Axh substantially parallel to the wall surface of the support wall 81. More specifically, the hinge 93 has a hinge rotational axis Axh, extends along the hinge rotational axis Axh, and is attached to the hinge rotation shaft 94 and the support wall 81 that can swing together with the support frame 30, and includes a shaft support plate 95 having a through hole through which the hinge rotation shaft 94 passes. As a result, the support frame 30 can be opened and closed so that the heat exchanger 7 can be rotated rearward, and a maintenance operator can perform maintenance work on the heat exchanger 7 and the engine 6.
Referring to FIGS. 3 to 6, the cooling fan 20 includes a fan rotational shaft 21 and a plurality of blades 22. The fan rotational shaft 21 has and extends along a fan rotational axis Axf around which the fan rotational shaft 21 is configured to rotate, the fan rotational shaft 21 being provided such that the fan rotational shaft 21 passes through the opening 82. As shown in FIG. 3 and the like, the fan rotational axis Axf and the hinge rotational axis Axh are lines (skewlines) at skew positions. In the present embodiment, the hinge rotational axis Axh, the fan rotational axis Axf, and the width direction Dw are substantially perpendicular to each other. Preferably, when the fan rotational axis Axf is projected onto the surface including the rotational axis Axh, the projected line is orthogonal to the hinge rotational axis Axh. However, when the fan rotational axis Axf is projected onto the surface including the hinge rotational axis Axh, the projected line is orthogonal to the hinge rotational axis Axh. The plurality of blades 22 are provided around the fan rotational shaft 21 in the radial direction with respect to the fan rotational axis Axf. The cooling fan 20 is configured to rotate the plurality of blades 22 around the fan rotational axis Axf to generate cooling air.
Referring to FIG. 4, the first shroud 10 is connected to the vehicle body frame 2 between the plurality of blades 22 and the support wall 81, and covers a part of the radially outer side of the blade reachable region 24 (a side surface of the blade reachable region 24 around the fan rotational axis Axf) of the plurality of blades 22. Referring to FIG. 5, the first shroud 10 has a first shape that is substantially arcuate as viewed in the axial direction DAX along the fan rotational axis Axf, and extends in the axial direction DAX. The first shape is a shape of the inner circumferential surface of the first shroud 10 as viewed in the axial direction DAX. Referring to FIG. 6, the first shroud 10 is supported by the vehicle body frame 2 via the stay 14. When the support frame 30 is located at the first position P1 at which the heat exchanger 7 is opposite to the cooling fan 20, the distal end portion 17 of the first shroud 10 and the second shroud 15 cover the outer periphery of the blade reachable region 24 in the radial direction.
Still referring to FIG. 6, the radius R2 of the second shape is substantially equal to the radius R1 of the first shape. When the support frame 30 is located at the first position P1, the center C1 of the first shape and the center C2 of the second shape substantially coincide with each other. The center C1 and the center C2 are located on the fan rotational axis Axf. The central angle θ2 of the second shape is 180 degrees or more, and the central angle θ1 of the first shape is 180 degrees or less. The distance L2 between the two end points E3 and E4 of the substantially circular arc shape of the second shape is larger than the diameter L24 of the blade reachable region 24 as viewed in the axial direction DAX. The distance L1 between the two end points E1, E2 of the substantially circular arc shape of the first shape is smaller than the diameter L24 of the blade reachable region 24. A gap 18 is provided between the two end points E1 and E3 to avoid collision between the first shroud 10 and the second shroud 15 due to rattling of the hinge 93. A gap 19 is provided between the two end points E2 and E4 to avoid collision between the first shroud 10 and the second shroud 15 due to rattling of the hinge 93.
FIG. 7 is a cross-sectional view taken along the line VII-VII' of FIG. 6. Referring to FIG. 7, when the support frame 30 is located at the first position P1 at which the heat exchanger 7 is opposite to the cooling fan 20, the first shroud 10 is in contact with the proximal end portion 16 of the second shroud 15. More specifically, referring to the enlarged view of the region A in FIG. 7, the first shroud 10 includes a first shroud body 11 and an elastic body 12. The first shroud 10 includes an elastic body 12 at a portion (a radially outer and rear end portion of the first shroud body 11) that abuts against the proximal end portion 16 of the second shroud 15 when the support frame 30 is located at the first position P1. Referring to FIGS. 5 and 7, when the support frame 30 is located at the first position P1 at which the heat exchanger 7 is opposite to the cooling fan 20, the first shroud 10 and the second shroud 15 cover the periphery of the cooling fan 20 in the radial direction so that the cooling air passes through the first surface 71 and the second surface 72.
FIG. 8 is a view of the second shroud 15, the support frame 30, and the second shroud 15, which are disposed at the second position P2, as viewed from the rear. Referring to FIG. 8, when the support frame 30 is located at the second position P2 where the opening 82 is exposed to the outside of the vehicle body frame 2, the fan rotational shaft 21, the plurality of blades 22, and the first shroud 10 are uncovered. Therefore an internal space opposite to the opening 82 with respect to the cooling fan 20 is accessible through a gap between the opening 82 and the plurality of blades 22.
In FIG. 7, a region that can be occupied by the blade reachable region 24 of the cooling fan 20 when the support frame 30 is rotated about the hinge rotational axis Axh is shown as R24. As can be seen from the fact that the region R24 does not contact the proximal end portion 16 on the left of the second shroud 15 and the distal end portion 17 on the right of the second shroud 15 in FIG. 7 and the fact that the region R24 does not contact the distal end portion 17 of the second shroud 15 in FIG. 6, the second shape is determined so that the distal end portion 17 of the second shroud 15 does not enter the blade reachable region 24 when the support frame 30 rotates from the second position P2 to the first position P1.
FIG. 9 is a top view of the rear portion of the work vehicle 1 when the upper cover 8 is removed. In FIG. 9, the engine 6 is not illustrated. As shown in FIG. 9, the hinge rotational axis Axh is provided on the side opposite to the cover rotational axis Axc with respect to the opening 82. That is, the bonnet cover 9 and the support frame 30 are configured to open on opposite sides, respectively. Therefore, the bonnet cover 9 and the support frame 30 form double doors opening from the center, and the second surface 72 can be covered by the bonnet cover 9. Referring to FIGS. 2, 3, and 8, the bonnet cover 9 has a plurality of air holes 92 in a portion of the bonnet cover 9 opposite to the second surface 72 when the bonnet cover 9 is turned to the position covering the second surface 72. The outside air sucked from the air holes 89 of the upper cover 8 and the like cools the engine 6 and the heat exchanger 7, and is then discharged from the plurality of air holes 92 of the bonnet cover 9.
Further, as shown in FIGS. 5, 6, 8 and 9, the support frame 30 has the roller 32 at the lower end thereof, and the roller 32 rolls on the bottom wall 83 of the vehicle body frame 2 when the maintenance worker moves the support frame 30, so that the maintenance worker can easily move the support frame 30. Further, since the support frame 30 is supported by the bottom wall 83 through the roller 32 during operation of the work vehicle 1, it is suppressed that a large load is applied to the hinge 93 for a long time.
As shown in FIG. 9, the hinge rotational axis Axh is located rearward of the rear end 81RE of the support wall 81. This allows the heat exchanger 7, the support frame 30, and the second shroud 15 to rotate 90 degrees or more around the hinge rotational axis Axh. That is, the orientation of the support frame 30 at the second position P2 is obtained by rotating 90 degrees or more about the hinge rotational axis Axh from the orientation of the support frame 30 at the first position P1. In FIG. 9, the heat exchanger 7, the support frame 30, and the second shroud 15 at the first position P1 are indicated by solid lines, and the support frame 30 and the second shroud 15 at the second position P2 are indicated by two dot chain lines, and the heat exchanger 7 at the second position P2 is indicated by one dot chain lines. The second position as illustrated indicates a position obtained by rotating 105 degrees from the first position P1.
Effect of First Embodiment
In the work vehicle 1 according to the first embodiment, the fan rotational shaft 21 and the plurality of blades 22 are exposed when the support frame 30 is located at the second position P2 where the opening 82 is exposed to the outside of the vehicle body frame 2. Therefore, when the member provided with the heat exchanger 7 is opened, access to the engine compartment is facilitated by utilizing the gap between the opening 82 and the plurality of blades 22. Further, the first shroud 10 is provided in the region where the distal end portion 17 of the second shroud 15 is cut out so that the second shroud 15 does not come into contact with the plurality of blades 22, and thus it is possible to increase the air volume of the cooling air passing through the heat exchanger 7, and to improve the cooling efficiency.
Second Embodiment
In the first embodiment, the gaps 18 and 19 are provided between the first shroud 10 and the second shroud 15, but by changing the shapes of the first shroud 10 and the second shroud 15, the gaps 18 and 19 may not be provided. The first shroud and the second shroud according to such a configuration are referred to as a first shroud 10a and a second shroud 15a, and the work vehicle including the first shroud 10a and the second shroud 15a is referred to as a work vehicle la. FIG. 10 is a front view showing the cooling fan 20, the first shroud 10a, the second shroud 15a, and the heat exchanger 7 according to the present embodiment. FIG. 11 is a front view showing the cooling fan 20, the first shroud 10a, the second shroud 15a, and the heat exchanger 7. FIG. 11 is a top view showing the cooling fan 20, the first shroud 10a, the second shroud 15a, and the heat exchanger 7. FIG. 12 is a left side view showing the cooling fan 20, the first shroud 10a, the second shroud 15a, and the heat exchanger 7. In FIGS. 10 to 12, the same components as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. In the second embodiment, only the structures of the first shroud 10a and the second shroud 15a are different. The structures of the first shroud 10a and the second shroud 15a other than the structures described below are the same as the structures of the first shroud 10 and the second shroud 15 of the first embodiment.
As shown in FIGS. 11 and 12, the first shroud body 11a of the first shroud 10a and the distal end portion 17a of the second shroud 15a are configured to obliquely contact each other, and the thicknesses of the distal end portion 17a of the second shroud 15a in the thickness direction Dt at the two end portions E5 and E6 of the first shroud body are substantially equal to the thicknesses of the distal end portion 17 of the second shroud 15 in the thickness direction Dt in the first embodiment. 17a. The width of the distal end portion 17a of the second shroud 15a in the thickness direction Dt is 0 near the end points E1 and E2 of the first embodiment. Therefore, the central angle θ1 of the first shape in the present embodiment is desirably 180 degrees or more. It is desirable that the inclination is gentle so that the elastic body 12 can absorb the displacement due to rattling of the hinge 93. In the first embodiment, the thickness of the first shroud body 11 in the thickness direction Dt is substantially equal to the thickness of the distal end portion 17 of the second shroud 15 in the thickness direction Dt. However, in the second embodiment, the maximum width of the first shroud body 11a in the thickness direction Dt is larger than the maximum width of the distal end portion 17a of the second shroud 15a in the thickness direction Dt.
Effect of Second Embodiment
The work vehicle la according to the second embodiment has a structure in which the first shroud body 11a of the first shroud 10a and the distal end portion 17a of the second shroud 15a obliquely contact each other, and thus the gaps 18 and 19 as in the first shroud 10 and the second shroud 15 may not be provided. Therefore, the work vehicle la according to the second embodiment can further increase the volume of the cooling air passing through the heat exchanger 7, and can further improve the cooling effect, in addition to the effects of the work vehicle 1 according to the first embodiment.
In this application, the word “comprise” and its derivatives are used as open-ended terms to describe the presence of elements but not to exclude the presence of other elements not listed. This applies to “having”, “including” and derivatives thereof. This applies to “having”, “including” and derivatives thereof.
The terms “member,” “part,” “element,” “body,” and “structure” may have a plurality of meanings, such as a single portion or a plurality of portions.
The ordinal numbers such as “first” and “second” are merely terms for identifying the configuration, and do not have other meanings (for example, a specific order). For example, the presence of a “first element” does not imply the presence of a “second element,” and the presence of a “second element” does not imply the presence of a “first element.”
Terms of degree such as “substantially”, “about”, and “approximately” can mean a reasonable amount of deviation such that the end result is not significantly changed, unless the embodiment is specifically described otherwise. All numerical values recited herein may be construed to include terms such as “substantially,” “about,” and “approximately.”
The phrase “at least one of A and B” as used herein should be interpreted to include A alone, B alone, and both A and B.
Obviously, numerous modifications and variations of the present disclosure are possible in light of the above teachings. Thus, it is to be understood that the embodiments may be practiced otherwise than as specifically described herein without departing from the scope of the disclosure.
Patent Application
20250230628
