JP6829672B2 - Construction machinery cooling fan - Google Patents

Description

The present invention relates to a cooling fan of a construction machine that supplies cooling air to a heat exchanger such as a radiator, and more particularly to a cooling fan in which the outer peripheral end portions of a plurality of blades are connected by a ring.

In construction machinery such as hydraulic excavators and dump trucks, a cooling unit including a heat exchanger such as a radiator or an oil cooler and a cooling fan that supplies cooling air at a flow rate required by the heat exchanger is generally an engine or the like. It is located inside the vehicle body together with the drive unit of the cooling fan. As one of the types of cooling fans, a fan in which the outer peripheral end portions of a plurality of blades are connected by a cylindrical member (ring), a so-called ring fan, is known.

In construction machinery, improvement of the cooling efficiency of the cooling unit is required in order to improve reliability and save energy. As a promising means for improving the cooling efficiency of the cooling unit, increasing the air volume of the cooling fan and increasing the efficiency can be mentioned. The techniques described in Patent Document 1 and Patent Document 2 are known as techniques for increasing the air volume and improving the efficiency of the cooling fan.

The cooling device described in Patent Document 1 includes an axial fan having a plurality of blades and a shroud arranged between the axial fan and the heat exchanger. A ring (fan ring) is attached to the outer peripheral end of the blade of the axial fan so as to surround the blade over the entire circumference, and this fan is a so-called ring fan. The ring has a protrusion that projects toward the outer circumference over the entire circumference. In the shroud, an adjustment plate divided into a plurality of parts in the circumferential direction is fixed to a variable distance from the outer peripheral surface of the ring. The technique described in Patent Document 1 can be easily assembled by the above configuration, and also reduces the flow of air (cooling air) flowing back from the discharge side to the suction side of the fan in the gap between the ring and the shroud to reduce the fan. This is to increase the air volume of.

The fan-housing coupling described in Patent Document 2 includes a ring fan (axial fan with a band) and a shroud (housing) for guiding an air flow, and the ring fan is positioned in the shroud. Steady flow control blades are arranged in the recirculation flow path between the ring (belt) and the shroud in a state of being connected to the shroud. The technique described in Patent Document 2 aims to improve efficiency by reducing the eddy current in the recirculated air flow that flows backward in the recirculation flow path between the ring (belt-shaped portion) and the shroud by the above configuration. is there.

Further, an effective means for increasing the air volume and improving efficiency in a general fan is to suppress the backflow of the gap between the blade and the shroud by reducing the gap (tip clearance) between the blade and the shroud. In the case of a ring fan, the wings are replaced with a ring, but by reducing the gap between the ring and the shroud, the pressure loss in the gap increases, so the effect of suppressing backflow is the same as for general fans. Can be expected.

International Publication WO 2005/098213 Pamphlet Special Table No. 9-505375

An effective means of suppressing backflow in a ring fan is to reduce the gap between the ring and the shroud. However, in construction machinery, the ring may come into contact with the shroud due to vibration of the vehicle body or the like, so it is necessary to widen the gap between the ring and the shroud as compared with a general fan. Therefore, there is a limit to the reduction of the gap. For example, when the fan (ring fan) described in Patent Document 1 is applied to a construction machine, there is a limit to the reduction of the gap between the ring and the adjustment plate, and the limit of this gap reduction limits the efficiency of the cooling fan. is there.

Further, as a means for improving the efficiency of the cooling fan other than reducing the gap between the ring and the shroud, a steady flow control blade connected to the shroud is provided in the gap between the ring and the shroud as in the technique described in Patent Document 2. By arranging it, there is one that reduces the eddy current in the recirculated air flow that flows back in the gap between the ring and the shroud. However, this steady flow control blade does not reduce the recirculated air flow itself.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to suppress backflow of the gap between the ring and the shroud while there is a limit to the reduction of the gap between the ring and the shroud. Is to provide a cooling fan for construction machinery.

The present application includes a plurality of means for solving the above problems. For example, it is a cooling fan of a construction machine arranged with a gap on the inner peripheral side of the shroud, and the space is spaced in the circumferential direction. The plurality of main wings are provided with a plurality of main wings arranged in a row and a ring connecting the outer peripheral end portions of the plurality of main wings so that at least one of the plurality of main wings is wider than the other wings. The ring has an enlarged diameter portion whose inner diameter and outer diameter expand in the discharge direction of the cooling fan, and the enlarged diameter portion is larger than the shroud in the axial direction of the cooling fan. A plurality of wing pieces are further provided on the outer peripheral portion of the enlarged diameter portion of the ring so as to be located on the discharge side of the ring, and the plurality of wing pieces are arranged at intervals in the circumferential direction. In the first region of the two main wings forming the space between the wide blades in the ring, which straddles the portion corresponding to the position of the front edge of the main blade on the rear side in the rotation direction of the cooling fan. It is composed of a plurality of arranged first wing pieces and a plurality of second wing pieces arranged outside the first region in the ring, and the plurality of first wing pieces are the plurality of second wing pieces. It is characterized in that it is formed in a shape that relaxes the stress generated in the joint portion with the ring rather than the blade piece portion.

According to the present invention, by arranging the wing piece portion on the outer peripheral portion of the enlarged diameter portion of the ring, a flow opposite to the flow flowing back through the gap between the ring and the shroud is generated. It is possible to suppress the backflow of the gap between the ring and the shroud while there is a limit to the reduction of the gap. As a result, it is possible to increase the air volume of the fan and improve the efficiency.
Issues, configurations and effects other than the above will be clarified by the following description of the embodiments.

It is a side view which shows the hydraulic excavator to which the 1st Embodiment of the cooling fan of the construction machine of this invention is applied. It is sectional drawing of the hydraulic excavator shown in FIG. 1 as seen from the arrow II-II, and is the figure which shows the internal structure of the machine room of a hydraulic excavator. It is a side view which shows the 1st Embodiment of the cooling fan of the construction machine of this invention, and the cooling apparatus including it in the state of a partial cross section. It is a figure which looked at the vicinity of the blade piece part which constitutes a part of the 1st Embodiment of the cooling fan of the construction machine of this invention from the suction side of a cooling fan. It is explanatory drawing which shows the operation of the 1st Embodiment of the cooling fan of the construction machine of this invention. It is a perspective view which looked at the 1st Embodiment of the cooling fan of the construction machine of this invention from the suction side. It is a front view which saw the 1st Embodiment of the cooling fan of the construction machine of this invention from the suction side. It is explanatory drawing which shows the deformed state during rotation drive in 1st Embodiment of the cooling fan of the construction machine of this invention. FIG. 5 is a perspective view seen from the suction side showing a part of the first embodiment of the cooling fan of the construction machine of the present invention indicated by reference numeral X in FIG. 7 in an enlarged state. It is a perspective view seen from the suction side which showed the part in the 2nd Embodiment of the cooling fan of the construction machine of this invention in the enlarged state. It is a perspective view seen from the suction side which showed the part in the 3rd Embodiment of the cooling fan of the construction machine of this invention in the enlarged state. It is a perspective view seen from the suction side which showed the part in the 4th Embodiment of the cooling fan of the construction machine of this invention in the enlarged state. FIG. 5 is a perspective view seen from the suction side showing a part of the cooling fan of the construction machine of the present invention in the fifth embodiment in an enlarged state. It is a perspective view seen from the suction side which showed the part in the 6th Embodiment of the cooling fan of the construction machine of this invention in the enlarged state.

Hereinafter, embodiments of the cooling fan of the construction machine of the present invention will be described with reference to the drawings. In the present embodiment, a hydraulic excavator will be described as an example of a construction machine.

First, the configuration of the hydraulic excavator to which the first embodiment of the cooling fan of the construction machine of the present invention is applied will be described with reference to FIGS. 1 and 2. FIG. 1 is a side view showing a hydraulic excavator to which the first embodiment of a cooling fan of a construction machine of the present invention is applied, and FIG. 2 is a cross-sectional view of the hydraulic excavator shown in FIG. 1 as viewed from the perspective of II-II. , It is a figure which shows the internal structure of the machine room of a hydraulic excavator. Here, the direction seen from the operator seated in the driver's seat will be described.

In FIG. 1, the hydraulic excavator 1 is mounted on a self-propelled crawler-type lower traveling body 2 and a lower traveling body 2 so as to be swivelable, and constitutes a vehicle body together with the lower traveling body 2. It is roughly composed of a work front 4 provided at the front end of the swivel body 3 so as to be able to move up and down.

The work front 4 is an articulated operating device for performing excavation work and the like, and includes a boom 6, an arm 7, and a bucket 8. The base end side of the boom 6 is rotatably connected to the front end portion of the upper swing body 3. A base end portion of the arm 7 is rotatably connected to the tip end portion of the boom 6. A base end portion of the bucket 8 is rotatably connected to the tip end portion of the arm 7. The boom 6, arm 7, and bucket 8 are rotated by the boom cylinder 6a, arm cylinder 7a, and bucket cylinder 8a, respectively.

The upper swivel body 3 includes a swivel frame 11 which is a support structure mounted on the lower traveling body 2 so as to be swivel, a cab 12 installed on the left front side on the swivel frame 11, and a rear end portion of the swivel frame 11. The counterweight 13 provided in the cab 12 and the machine room 14 arranged between the cab 12 and the counterweight 13 are included. The cab 12 is provided with an operating device for instructing the operation of the lower traveling body 2 and the work front 4, a driver's seat on which the operator is seated (both not shown), and the like. The counter weight 13 is for balancing the weight with the work front 4.

As shown in FIG. 2, the machine room 14 accommodates a large number of devices such as an engine 20 as a prime mover, a hydraulic pump 21 driven by the engine 20, and a cooling device 30 for cooling the engine 20, the hydraulic pump 21, and the like. There is. The cooling device 30 includes a heat exchange device 31 and a cooling fan 32, which will be described in detail later. For example, the cooling device 30 is arranged on the opposite side of the hydraulic pump 21 with the engine 20 in between. The outer shell of the machine room 14 is formed by a building cover 16. On the cooling device 30 side (left side) of the building cover 16, a suction port 16a for taking in outside air is provided in the machine room 14. On the side (right side) of the hydraulic pump 21 of the building cover 16, a discharge port 16b for discharging air from the inside of the machine room 14 is provided.

Next, the first embodiment of the cooling fan of the construction machine of the present invention and the configuration of the cooling device including the first embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a side view showing a first embodiment of the cooling fan of the construction machine of the present invention and a cooling device including the first embodiment in a partially cross-sectional state, and FIG. 4 is a first embodiment of the cooling fan of the construction machine of the present invention. It is the figure which looked at the vicinity of the blade piece part which constitutes a part of an Embodiment from the suction side of a cooling fan. In addition, in FIGS. 3 and 4, those having the same reference numerals as those shown in FIGS. 1 and 2 are the same parts, and thus detailed description thereof will be omitted.

In FIG. 3, the cooling device 30 includes a heat exchange device 31, a cooling fan 32 that generates cooling air for cooling the heat exchange device 31, and a shroud 33 that guides the cooling air to the heat exchange device 31. There is.

The heat exchanger 31 is composed of, for example, a heat exchanger such as a radiator or an oil cooler. The radiator cools the cooling water of the engine 20, and the oil cooler operates through a hydraulic circuit including hydraulic cylinders 6a, 7a, 8a (see FIG. 1) and a hydraulic pump 21 (see FIG. 2) of the work front 4. It cools the oil. The heat exchange device 31 is arranged so as to face the cooling fan 32 on the suction side of the cooling fan 32.

A rotating shaft 23 is attached to the cooling fan 32. The rotary shaft 23 is rotatably supported by the engine 20 above the drive shaft (output shaft) 20a of the engine 20. Pulleys 24 and 25 are provided on the rotary shaft 23 and the drive shaft 20a of the engine 20, respectively. A belt 26 is hung between the pulley 24 on the rotating shaft 23 side and the pulley 25 on the drive shaft 20a side. With this configuration, the engine 20 functions as a drive device for rotationally driving the cooling fan 32. Further, both pulleys 24 and 25 and the belt 26 function as a power transmission mechanism for transmitting the power of the engine 20 to the cooling fan 32.

A shroud 33 is fixed to the cooling fan 32 side (right side in FIG. 3) of the heat exchange device 31. The shroud 33 is composed of a tubular portion 35 extending in the axial direction of the cooling fan 32 and an overhanging portion 36 protruding inward in the radial direction from the entire circumference of the end portion of the tubular portion 35 on the cooling fan 32 side. , Part of the outer edge of the cooling fan 32 is surrounded. The inner peripheral edge 36a of the overhanging portion 36 forms a circular opening, and faces the outer edge portion of the cooling fan 32 with a gap d1.

The cooling fan 32 is a so-called ring fan, and includes a boss 41 to which the rotating shaft 23 is attached, and a plurality of main wings 42 arranged at intervals in the circumferential direction on the outer peripheral portion of the boss 41 for ventilation and boosting. A ring 43 for connecting the outer peripheral end portion 42a of the main wing 42 of the above is provided. The cooling fan 32 is made of resin, for example, and the boss 41, the main wing 42, and the ring 43 are integrally molded.

The ring 43 has a tubular shape whose discharge side is widened toward the end. That is, the inner and outer diameters of the ring 43 are substantially equal to the outer diameter of the main wing 42, and the ring main body 45 in contact with the outer peripheral end 42a of the main wing 42 and the discharge side end of the ring main body 45 (FIG. 3). , It is composed of a diameter-expanded portion 46 whose inner diameter and outer diameter gradually increase from the right end portion) to the discharge direction (right direction in FIG. 3). The suction side end of the ring body 45 is located closer to the suction side than the front edge 42b of the main wing 42, and the discharge side end (the right end in FIG. 3) is closer to the trailing edge 42c of the main wing 42. It is configured to be located on the discharge side. That is, the ring main body 45 is configured so that the entire outer peripheral end portion 42a of the main wing 42 is arranged inside the ring main body 45. On the outer peripheral side of the ring main body 45, the inner peripheral edge 36a of the overhanging portion 36 of the shroud 33 is arranged with a gap d1. The diameter-expanded portion 46 is located on the discharge side of the overhanging portion 36 of the shroud 33 in the axial direction of the cooling fan 32, and has a trumpet shape in which the diameter is expanded by drawing a curve from the suction side to the discharge side. ing. The ring 43 is composed of a tubular member having a substantially constant plate thickness, and the outer diameter of the ring 43 changes in the same manner as the inner diameter.

On the outer peripheral surface of the enlarged diameter portion 46 of the ring 43, a plurality of blade piece portions 50 having a blade action protruding outward are provided at intervals over the entire circumferential direction. The wing piece portion 50 has a size similar to the difference between the maximum diameter and the minimum diameter of the enlarged diameter portion 46 of the ring 43 and the size of the gap d1 between the ring 43 and the shroud 33, and the main wing 42 that generates cooling air. Extremely small compared to. The blade piece portions 50 are arranged at intervals d2 on the discharge side of the overhanging portion 36 of the shroud 33 in the axial direction of the cooling fan 32. The blade piece 50 is, for example, a substantially fan-shaped plate-shaped member, so that the leading edge 50b of the blade is substantially parallel to the radial direction of the cooling fan 32 and the trailing edge 50c of the blade is substantially parallel to the axial direction of the cooling fan 32. It is configured in. That is, the leading edge 50b of the blade is the suction side end in the axial direction (the left end in FIG. 3), and the trailing edge 50c of the blade is the outer peripheral end of the blade piece portion 50. The outer peripheral end 50c of the blade piece portion 50 is located, for example, radially inside the outer peripheral end of the enlarged diameter portion 46. Further, as shown in FIG. 4, the blade piece portion 50 is configured to tilt backward with respect to the rotation direction of the cooling fan 32. That is, the blade piece portion 50 is inclined so that the outer peripheral end 50c of the leading edge 50b of the blade is located behind the root portion (the joint portion with the enlarged diameter portion 46 of the ring 43) 50a in the rotational direction of the cooling fan 32. doing. As shown in FIG. 3, these wing piece portions 50 rotate integrally with the main wing 42 and the ring 43.

Next, the operation of the first embodiment of the cooling fan of the construction machine of the present invention will be described with reference to FIGS. 2 and 5. FIG. 5 is an explanatory diagram showing the operation of the first embodiment of the cooling fan of the construction machine of the present invention. In FIG. 2, the thick arrow indicates the flow of the cooling air. In FIG. 5, those having the same reference numerals as those shown in FIGS. 1 to 4 are the same parts, and thus detailed description thereof will be omitted.

When the cooling fan 32 shown in FIG. 2 is driven by the engine 20, outside air is sucked from the suction port 16a of the building cover 16 of the machine room 14, and cooling air is generated in the machine room 14. This cooling air cools the heat exchange device 31 in the machine room 14, and then is discharged from the cooling fan 32 via the shroud 33. The cooling air discharged from the cooling fan 32 is discharged to the outside from the discharge port 16b of the building cover 16 after cooling the peripheral portion of the engine 20 and the hydraulic pump 21. In this way, the heat exchange device 31 and other devices housed in the machine room 14 are cooled by the cooling air generated by the cooling fan 32, so that they can be operated normally.

In the cooling fan 32 shown in FIG. 5, the rotation of the main wing 42 causes the main flow α to flow from the suction side to the discharge side of the cooling fan 32, and a pressure difference is generated between the suction side and the discharge side. Due to this pressure difference, air flows in the direction opposite to the mainstream α from the discharge side of the overhanging portion 36 of the shroud 33 arranged on the outer peripheral side of the ring 43 toward the gap d1 between the ring 43 and the overhanging portion 36. (Backflow) β occurs. This backflow β causes a decrease in air volume and a decrease in efficiency of the cooling fan 32.

In the present embodiment, the blade piece portion 50 provided on the ring 43 rotates integrally with the main wing 42, so that a radial outward flow γ is generated on the outer peripheral side of the ring 43. This flow γ is a flow opposite to the backflow β flowing between the ring 43 and the shroud 33. Since the backflow β is hindered by the flow γ in the opposite direction, the flow rate of the backflow β flowing through the gap d1 between the ring 43 and the overhanging portion 36 of the shroud 33 is reduced as compared with the case where the blade piece portion 50 is not provided. Will be done. Therefore, the efficiency of the cooling fan 32 can be improved by the amount that the flow rate of the backflow β is reduced.

Further, in the present embodiment, since the wing piece portion 50 provided on the outer peripheral surface of the enlarged diameter portion 46 of the ring 43 has a wing action, the wing piece portion 50 rotates integrally with the main wing 42. By doing so, it exerts a pressor action by itself. Therefore, the effective fan outer diameter of the cooling fan 32 is determined by the position of the outer peripheral end 50c of the blade piece portion 50, and becomes D2 shown in FIG. On the other hand, the effective fan outer diameter of the cooling fan having no blade piece 50 is determined by the position of the outer peripheral end portion 42a of the main blade 42, and is D1 shown in FIG. That is, the effective fan outer diameter of the cooling fan 32 of the present embodiment is larger by the amount of the blade piece 50 than D1 in the case of the cooling fan having no blade piece 50, and increases to D2. The effective work performed on the air of the cooling fan 32, that is, the increase in total pressure is proportional to the square of the outer diameter of the fan. Therefore, in the cooling fan 32 of the present embodiment, the air volume increases at the same rotation speed as compared with the case of the cooling fan having the configuration without the blade piece portion 50.

In addition, in the present embodiment, the blade piece 50 is tilted so that the outer peripheral end 50c of the blade leading edge 50b of the blade piece 50 is located behind the root portion 50a in the rotational direction of the cooling fan 32. (See Fig. 4). In the case of this configuration, it has been confirmed that the static pressure efficiency of the fan is increased as compared with the case where the blade piece 50 is not tilted.

Further, in the present embodiment, the ring 43 is configured so that the inner and outer diameters of the ring 43 on the discharge side are increased. In this case, of the main flow α discharged from the main wing 42, the flow on the outer peripheral side spreads outward in the smooth radial direction along the inner peripheral surface of the enlarged diameter portion 46 of the ring 43, so that the discharge side of the ring 43 is expanded in diameter. The generation of vortices around the discharge side end of the ring 43 is reduced as compared with the case where the diameters are the same. The efficiency of the cooling fan 32 increases as the generation of vortices is reduced.

As described above, in the present embodiment, the effect of increasing the air volume and improving the efficiency of the cooling fan 32 can be obtained without reducing the gap d1 between the ring 43 and the shroud 33. By increasing the air volume of the cooling fan 32, it is possible to suppress the temperature rise of various devices such as the heat exchange device 31 in the machine room 14, and the reliability of the hydraulic excavator 1 is improved. Further, since the power consumption can be reduced by improving the efficiency of the cooling fan 32, it is possible to realize energy saving of the hydraulic excavator 1.

By the way, in construction machinery, in order to ensure the comfort of the operator, it is required to suppress the peak noise generated from the cooling fan 32, that is, the noise at the blade passing frequency. Therefore, in the present embodiment, the plurality of main wings 42 of the cooling fan 32 are arranged at unequal pitches (different intervals) in the rotation direction.

Next, the arrangement of the main wings of the cooling fan will be described with reference to FIGS. 6 and 7. FIG. 6 is a perspective view of the first embodiment of the cooling fan of the construction machine of the present invention as viewed from the suction side, and FIG. 7 is the first embodiment of the cooling fan of the construction machine of the present invention indicated by reference numeral X in FIG. It is a perspective view seen from the suction side which showed the part of the form in an enlarged state. In addition, in FIGS. 6 and 7, those having the same reference numerals as those shown in FIGS. 1 to 5 are the same parts, and thus detailed description thereof will be omitted.

In FIGS. 6 and 7, the cooling fan 32 has, for example, seven main wings 42, and these main wings 42 are arranged at different intervals in the rotation direction. That is, between the seven main wings 42, a relatively wide space between the blades (hereinafter, may be referred to as a first blade) and a relatively narrow space between the blades (hereinafter, referred to as a second blade). There is) P2 and. In the present embodiment, for example, the main wing 42 is arranged so that there are two wing P1s that are relatively wide as compared with other blades. Further, the cooling fan 32 has, for example, 62 blade piece portions 50. These blade pieces 50 are arranged at equal pitches (same intervals) in the rotation direction, for example.

When the main wings 42 are arranged at unequal pitches in this way, when the cooling fan 32 is operated, the portion of the ring 43 located at the relatively wide inter-blade P1 is located at the other inter-blade (relatively narrow inter-blade) P2. It may be deformed more than the part to be used.

Next, the result of deformation analysis of the cooling fan in which the main wings are arranged at unequal pitches will be described with reference to FIG. FIG. 8 is an explanatory view showing a deformed state during rotational driving in the first embodiment of the cooling fan of the construction machine of the present invention, and is a front view seen from the suction side of the cooling fan. The cooling fan in FIG. 8 shows an extremely deformed state. In FIG. 8, those having the same reference numerals as those shown in FIGS. 1 to 7 are the same parts, and thus detailed description thereof will be omitted.

From the result of the deformation analysis shown in FIG. 8, it can be seen that the deformation of the portion of the ring 43 located at the first interwing P1 is larger than the deformation of the portion located at the second interwing P2. More specifically, at the suction side end of the ring main body 45 of the ring 43, the portion located at the first blade inter-blade P1 is deformed particularly greatly inward in the radial direction. On the other hand, among the main wings 42 (Wf) and 42 (Wr) forming the first inter-blade P1, a predetermined value including the front edge 42b (Wr) of the main wings 42 (Wr) located on the rear side in the rotation direction of the cooling fan 32. The part located in the region of is greatly deformed radially outward.

According to the result of this deformation analysis, when the wing piece portion 50 provided in the enlarged diameter portion 46 of the ring 43 receives a centrifugal force outward in the radial direction, the joint portion (root portion) with the deformed ring 43 in the wing piece portion 50. The local stress generated in the area increases. In the wing piece portion 50 arranged in the enlarged diameter portion 46 of the ring 43 in the portion corresponding to the predetermined region straddling the front edge 42b (Wr) of the main wing 42 (Wr) in which the deformation becomes particularly large, the joint portion with the ring 43. The local stress generated in is particularly large.

In this way, in order to reduce the noise of the cooling fan 32 while increasing the air volume and improving the efficiency of the cooling fan 32, the blade piece portions 50 are arranged on the outer peripheral portion of the enlarged diameter portion 46 of the ring 43, and a plurality of blade pieces are arranged. When the main wings 42 of the above are arranged at unequal pitches, there is the above-mentioned problem. Therefore, in the present embodiment, the blade piece portion 50, which has a particularly large local stress, is configured to have a shape that relieves the stress generated at the joint portion with the ring 43.

Next, the configuration and structure of the plurality of blade pieces will be described with reference to FIGS. 7 and 9. FIG. 9 is a perspective view of a part of the first embodiment of the cooling fan of the construction machine of the present invention indicated by reference numeral X in FIG. 7 as viewed from the suction side in an enlarged state. In FIG. 9, those having the same reference numerals as those shown in FIGS. 1 to 8 are the same parts, and thus detailed description thereof will be omitted.

In FIGS. 7 and 9, the plurality of blade pieces 50 are two main wings 42 (Wf), 42 (Wr) that are located in the relatively wide inter-blade P1 in the ring 43 and form the inter-blade P1. ), Which is arranged in a predetermined region (hereinafter referred to as the first region) R1 straddling the portion corresponding to the position of the front edge 42b (Wr) of the main wing 42 (Wr) on the rear side in the rotation direction of the cooling fan 32. It is composed of a plurality of first wing piece portions 51 and a plurality of second wing piece portions 52 arranged outside the first region. In the present embodiment, there are two first region R1s, and the number of first wing piece portions 51 arranged in each first region R1 is, for example, four. This first region R1 is a region having a particularly large local stress found by the above-mentioned deformation analysis of the cooling fan, and depends on conditions such as the diameter of the ring 43, the size of the inter-blade P1, and the size of the enlarged diameter portion 46. The range is determined.

The first wing piece portion 51 is formed in a shape that relaxes the stress generated at the joint portion with the ring 43 as compared with the second wing piece portion 52. Specifically, as shown in FIG. 9, the first wing piece portion 51 includes a corner portion (joint portion) between the side surface on the rotation direction side and the enlarged diameter portion 46 of the ring 43, and a side surface and the ring on the opposite rotation direction side. The rotating side fillet portion 51a and the counter-rotating side fillet portion 51b are provided at the corners (joining portions) of the 43 with the enlarged diameter portion 46, respectively. Similarly, the second wing piece portion 52 has a corner (joint portion) between the side surface on the rotation direction side and the enlarged diameter portion 46 of the ring 43 and a corner between the side surface on the opposite rotation direction side and the enlarged diameter portion 46 of the ring 43. The portion (joining portion) has a rotating side fillet portion 52a and a counter-rotating side fillet portion 52b, respectively. The counter-rotating fillet portion 51b of the first wing piece portion 51 is set to be relatively larger than the counter-rotating side fillet portion 52b of the second wing piece portion 52. On the other hand, the rotation-side fillet portion 51a of the first wing piece portion 51 is set to have substantially the same size as the rotation-side fillet portion 52a of the second wing piece portion 52.

In the present embodiment, a fillet portion 51b that is relatively larger than the fillet portion 52b of the second wing piece portion 52 is provided with respect to the joint portion (root portion) of the first wing piece portion 51 with the ring 43. Therefore, it is possible to exert the effect of suppressing the local stress generated at the joint portion (root portion) of the first wing piece portion 51 by that amount.

As described above, according to the first embodiment of the cooling fan of the construction machine of the present invention, the ring 43 and the shroud 33 are formed by arranging the wing piece portion 50 on the outer peripheral portion of the enlarged diameter portion 46 of the ring 43. Since a flow γ opposite to the flow β flowing back through the gap d1 is generated, there is a limit to the reduction of the gap d1 between the ring 43 and the shroud 33, and the gap d1 between the ring 43 and the shroud 33 Backflow β can be suppressed. As a result, it is possible to increase the air volume of the fan and improve the efficiency.

Further, according to the present embodiment, since the plurality of main wings 42 are arranged at unequal pitches, the noise of the fan can be reduced.

Further, according to the present embodiment, among the plurality of wing piece portions 50, the first wing piece portion 51 arranged in the first region R1 which is greatly affected by the increase in deformation of the ring 43 due to the unequal pitch of the main wing 42 is provided. , Since it is configured to have a shape that relaxes the stress generated in the joint portion with the ring 43 rather than the second wing piece portion 52 arranged outside the first region, the joint portion with the ring 43 in the first wing piece portion 51. The local stress generated at the (root portion) can be further reduced.

That is, according to the present embodiment, it is possible to reduce the noise of the cooling fan 32 and reduce the local stress generated in the blade piece portion 50 while maintaining the increase in the air volume and the high efficiency of the cooling fan 32.

Further, according to the present embodiment, the fillet portion 51b of the first wing piece portion 51 arranged in the first region R1 is made larger than the fillet portion 52b of the second wing piece portion 52 arranged outside the first region. Since it is set to, the material for forming the cooling fan 32 is larger than the case where both the fillet portions of the first wing piece portion 51 and the second wing piece portion 52 have the same size as the fillet portion of the first wing piece portion 51. The amount of the fillinget used can be reduced, and as a result, the manufacturing cost can be reduced.

Further, according to the present embodiment, the first wing piece portion 51 and the second wing piece portion 52 constituting the wing piece portion 50 are configured to be tilted backward with respect to the rotation direction of the cooling fan 32, and the first wing piece portion 52 is configured. Since the fillet portion 52b is provided at the base of the side surface of the 1st wing piece portion 51 and the 2nd wing piece portion 52 on the anti-rotation direction side, the first wing piece portion 51 and the first wing piece portion 51 tilting backward are provided along with further improvement in the efficiency of the fan. It is possible to relieve the stress generated at the joint portion between the second blade piece portion 52 and the enlarged diameter portion 46 of the ring 43.

Next, a second embodiment of the cooling fan of the construction machine of the present invention will be described with reference to FIG. FIG. 10 is a perspective view seen from the suction side showing a part of the cooling fan of the construction machine of the present invention in an enlarged state in the second embodiment. In FIG. 10, those having the same reference numerals as those shown in FIGS. 1 to 9 have the same reference numerals, and thus detailed description thereof will be omitted.

The second embodiment of the cooling fan of the construction machine of the present invention differs from the first embodiment as follows. In the cooling fan 32 according to the first embodiment, of the plurality of blade piece portions 50, the counter-rotating fillet portion 51b of the first blade piece portion 51 arranged in the first region R1 is arranged outside the first region. The second wing piece portion 52 is made relatively larger than the counter-rotating side fillet portion 52b (see FIG. 9). On the other hand, in the cooling fan 32A according to the second embodiment shown in FIG. 10, the thickness of the first blade piece portion 51A arranged in the first region R1 is outside the first region among the plurality of blade piece portions 50A. It is relatively thinner than the thickness of the second wing piece portion 52A arranged in. Further, although the first wing piece portion 51A and the second wing piece portion 52A of the present embodiment do not have a fillet portion at the root portion thereof, a configuration having a fillet portion is also possible.

In the present embodiment, the thickness of the first wing piece portion 51A arranged in the first region R1 is thinner than the thickness of the second wing piece portion 52A arranged outside the first region. The mass of the portion 51A is smaller than the mass of the second wing piece portion 52A. Therefore, the centrifugal force acting on the first wing piece portion 51A becomes smaller than the centrifugal force acting on the second wing piece portion 52A, and the centrifugal force acting on the first wing piece portion 51A is correspondingly smaller than the centrifugal force acting on the first wing piece portion 51A with the enlarged diameter portion 46 of the ring 43 in the first wing piece portion 51A. Local stress generated at the joint (root) can be reduced.

According to the second embodiment of the cooling fan of the construction machine of the present invention described above, the same effect as that of the first embodiment described above can be obtained.

Further, according to the present embodiment, the amount of the material used for molding the cooling fan 32A can be reduced by the amount that the thickness of the first wing piece portion 51A is made thinner than the thickness of the second wing piece portion 52A. , The manufacturing cost can be reduced.

Next, a third embodiment of the cooling fan of the construction machine of the present invention will be described with reference to FIG. FIG. 11 is a perspective view of the cooling fan of the construction machine of the present invention as viewed from the suction side, showing a part of the cooling fan according to the third embodiment in an enlarged state. In FIG. 11, those having the same reference numerals as those shown in FIGS. 1 to 10 have the same parts, and thus detailed description thereof will be omitted.

The third embodiment of the cooling fan of the construction machine of the present invention differs from the second embodiment as follows. The cooling fan 32A according to the second embodiment has a second blade piece portion in which the thickness of the first blade piece portion 51A arranged in the first region R1 is arranged outside the first region among the plurality of blade piece portions 50A. It is relatively thinner than the thickness of 52A (see FIG. 10). On the other hand, the cooling fan 32B according to the third embodiment shown in FIG. 11 has an axial length of the first blade piece portion 51B arranged in the first region R1 among the plurality of blade piece portions 50B. It is relatively shorter than the axial length of the second wing piece portion 52A arranged outside the first region.

In the present embodiment, the axial length of the first wing piece portion 51B arranged in the first region R1 is relatively shorter than the axial length of the second wing piece portion 52A arranged outside the first region. Therefore, the mass of the first wing piece portion 51B is smaller than the mass of the second wing piece portion 52A. Therefore, as in the case of the second embodiment, the centrifugal force acting on the first wing piece portion 51B becomes smaller than the centrifugal force acting on the second wing piece portion 52A, and the first wing piece portion is correspondingly smaller. It is possible to reduce the local stress generated at the joint portion (root portion) of the ring 43 with the enlarged diameter portion 46 of the 51B.

According to the third embodiment of the cooling fan of the construction machine of the present invention described above, the same effect as that of the second embodiment described above can be obtained.

Next, a fourth embodiment of the cooling fan of the construction machine of the present invention will be described with reference to FIG. FIG. 12 is a perspective view of the cooling fan of the construction machine of the present invention as viewed from the suction side, showing a part of the cooling fan according to the fourth embodiment in an enlarged state. In FIG. 12, those having the same reference numerals as those shown in FIGS. 1 to 11 have the same reference numerals, and thus detailed description thereof will be omitted.

The fourth embodiment of the cooling fan of the construction machine of the present invention differs from the third embodiment as follows. In the cooling fan 32B according to the third embodiment, among the plurality of blade piece portions 50B, the axial length of the first blade piece portion 51B arranged in the first region R1 is arranged outside the first region. It is relatively shorter than the axial length of the two wing piece portion 52A (see FIG. 11). On the other hand, the cooling fan 32C according to the fourth embodiment shown in FIG. 12 has a radial length of the first blade piece portion 51C arranged in the first region R1 among the plurality of blade piece portions 50C. It is relatively shorter than the radial length of the second wing piece portion 52A arranged outside the first region.

In the present embodiment, the radial length of the first wing piece portion 51C arranged in the first region R1 is relatively shorter than the radial length of the second wing piece portion 52A arranged outside the first region. Therefore, the mass of the first wing piece portion 51C is smaller than the mass of the second wing piece portion 52A. Therefore, as in the case of the third embodiment, the centrifugal force acting on the first wing piece portion 51C becomes smaller than the centrifugal force acting on the second wing piece portion 52A, and the first wing piece portion is correspondingly smaller. It is possible to reduce the local stress generated at the joint portion (root portion) of the ring 43 with the enlarged diameter portion 46 of the 51C.

Further, since the length in the radial direction is relatively short, the rotation speed of the first blade piece portion 51C is smaller than the rotation speed of the second blade piece portion 52A. By that amount, the centrifugal force acting is smaller than that in the case of the third embodiment. Therefore, the centrifugal force acting on the first wing piece portion 51C becomes smaller than the centrifugal force acting on the second wing piece portion 52A, and the coupling with the enlarged diameter portion 46 of the ring 43 in the first wing piece portion 51C by that amount. It is possible to reduce the local stress generated in the portion (root portion).

According to the fourth embodiment of the cooling fan of the construction machine of the present invention described above, the same effect as that of the third embodiment described above can be obtained.

Next, a fifth embodiment of the cooling fan of the construction machine of the present invention will be described with reference to FIG. FIG. 13 is a perspective view of the cooling fan of the construction machine of the present invention as viewed from the suction side, showing a part of the cooling fan according to the fifth embodiment in an enlarged state. In FIG. 13, those having the same reference numerals as those shown in FIGS. 1 to 12 have the same reference numerals, and thus detailed description thereof will be omitted.

The fifth embodiment of the cooling fan of the construction machine of the present invention differs from the first embodiment as follows. In the cooling fan 32 according to the first embodiment, of the plurality of blade piece portions 50, the counter-rotating fillet portion 51b of the first blade piece portion 51 arranged in the first region R1 is arranged outside the first region. The second wing piece portion 52 is made relatively larger than the counter-rotating side fillet portion 52b (see FIG. 9). On the other hand, the cooling fan 32D according to the fifth embodiment shown in FIG. 13 has a configuration in which the first blade piece portion 51D arranged in the first region R1 is connected by the rib 54 among the plurality of blade piece portions 50D. The second wing piece portion 52 arranged outside the first region has a rib-free configuration.

Specifically, each of the plurality of first blade piece portions 51D arranged in the first region R1 has a rib 54 at the suction side end portion in the axial direction thereof. The rib 54 extends in the circumferential direction and connects a plurality of first wing piece portions 51D. The radial length of the rib 54 is substantially the same as the radial length of the suction side end portion of the first blade piece portion 51D. By the function of the rib 54, it is possible to reduce the local stress generated in the joint portion (root portion) of the ring 43 with the enlarged diameter portion 46 in the first blade piece portion 51D.

According to the fifth embodiment of the cooling fan of the construction machine of the present invention described above, the same effect as that of the first embodiment described above can be obtained.

Further, according to the present embodiment, since the rib 54 is provided on the first wing piece portion 51D, the rigidity of the first wing piece portion 51D can be increased as compared with the case of the first embodiment. Further, since the rib 54 is provided so as to connect the plurality of first wing piece portions 51D, the rigidity of the first wing piece portion 51D can be further increased.

Next, a sixth embodiment of the cooling fan of the construction machine of the present invention will be described with reference to FIG. FIG. 14 is a perspective view of the cooling fan of the construction machine of the present invention as viewed from the suction side, showing a part of the cooling fan according to the sixth embodiment in an enlarged state. In FIG. 14, those having the same reference numerals as those shown in FIGS. 1 to 13 have the same reference numerals, and thus detailed description thereof will be omitted.

The sixth embodiment of the cooling fan of the construction machine of the present invention shown in FIG. 14 differs from the first embodiment in that a plurality of blade piece portions 50E are arranged in the first region R1. Instead of being composed of the first wing piece portion 51 and a plurality of second wing piece portions 52 arranged outside the first region, it is composed of only the second wing piece portion 52 arranged outside the first region. is there. That is, the plurality of blade piece portions 50E are not arranged in the first region R1, but are arranged in the entire circumferential direction of the ring 43 excluding the first region R1. In this case, since the blade piece portion (first blade piece portion) is not arranged in the first region R1 where an increase in local stress is a concern, there is no need to worry about an increase in the local stress of the blade piece portion.

According to the sixth embodiment of the cooling fan of the construction machine of the present invention described above, the same effect as that of the first embodiment described above can be obtained.

Further, according to the present embodiment, since the blade piece portion 50E is not arranged in the first region R1, the amount of the material used for molding the cooling fan 32E can be reduced, and as a result, the manufacturing cost can be reduced. ..

The present invention is not limited to the present embodiment, and includes various modifications. The above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations. It is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

For example, in the first to sixth embodiments of the construction machine of the present invention described above, an example in which the cooling fan of the construction machine of the present invention is applied to the hydraulic excavator 1 is shown, but the present invention includes a hydraulic crane and the like. It can be widely applied to various construction machines such as wheel loaders.

Further, in the above-described embodiment, the engine 20 is used as the drive device for the cooling fan 32, but an electric motor, a hydraulic motor, or the like can also be used as the drive device.

Further, in the above-described embodiment, an example is shown in which the seven main wings 42 of the cooling fan 32 are arranged so that there are two P1s that are relatively wide compared to the other blades. However, it is possible to obtain the effect of reducing fan noise by arranging an arbitrary number of main wings so that at least one of the wings is relatively wider than the other wings. Further, there may be a relative width in the relatively wide space between the blades P1 and the relatively narrow space between the blades P2. That is, it is possible to arrange the main wings so that the plurality of wings are all different.

Further, in the above-described embodiment, an example is shown in which the ring main body 45 is configured so that the entire outer peripheral end portion 42a of the main wing 42 is arranged inside the ring main body 45 of the ring 43. The shape of the main body is not limited to this. For example, the ring main body may be configured so that the suction side end of the ring main body is located on the discharge side of the front edge 42b of the main wing 42. Further, the ring main body may be configured so that the discharge side end of the ring main body is located on the suction side of the trailing edge 42c of the main wing 42.

Further, in the above-described embodiment, the blade piece portion 50 is such that the blade leading edge 50b is substantially parallel to the radial direction of the cooling fan 32 and the blade trailing edge 50c is substantially parallel to the axial direction of the cooling fan 32. Although an example of a substantially fan shape is shown, the shape of the wing piece may be any shape having a wing action.

Further, in the above-described embodiment, an example of a resin cooling fan 32 in which the boss 41, the main wing 42, the ring 43, and the wing piece portion 50 are integrally molded is shown, but the boss 41, the main wing 42, the ring 43, It is also possible to form a cooling fan by joining the members after manufacturing the wing piece portions 50 separately.

Further, in the second to fourth embodiments described above, the thickness, the axial length, and the radial length of the first blade pieces 51A, 51B, and 51C arranged in the first region R1 are set to the first. Centrifugal action on the first wing pieces 51A, 51B, 51C by making it relatively smaller than the thickness, axial length, and radial length of the second wing piece 52A arranged outside one region. An example is shown in which the force is configured to be smaller than the centrifugal force acting on the second wing piece portion 52A. However, by forming the first wing piece portion in a shape other than the above, which has a smaller mass than the second wing piece portion, the centrifugal force acting on the first wing piece portion acts on the second wing piece portion. It can be smaller than the force.

1 ... Hydraulic excavator (construction machinery), 32, 32A, 32B, 32C, 32D, 32E ... Cooling fan, 33 ... Shroud, 42 ... Main wing, 43 ... Ring, 46 ... Enlarged part, 50, 50A, 50B, 50C, 50D, 50E ... wing piece, 51, 51A, 51B, 51C, 51D ... first wing piece, 52, 52A ... second wing piece, 51b ... counter-rotating fillet (fillet), 52b ... counter-rotating Side fillet part (fillet part), 54 ... Rib

Claims (9)

A cooling fan for construction machinery that is placed with a gap on the inner circumference side of the shroud.
With multiple main wings arranged at intervals in the circumferential direction,
A ring for connecting the outer peripheral end portions of the plurality of main wings is provided.
The plurality of wings are arranged so that at least one of the wings is wider than the other wings.
The ring has an enlarged diameter portion whose inner diameter and outer diameter expand in the discharge direction of the cooling fan, and the enlarged diameter portion is closer to the discharge side of the cooling fan than the shroud in the axial direction of the cooling fan. Arranged to be located,
A plurality of wing pieces arranged at intervals in the circumferential direction are further provided on the outer peripheral portion of the enlarged diameter portion of the ring.
The plurality of blade pieces are located between the wide blades in the ring and are located at the front edge of the main blade on the rear side in the rotation direction of the cooling fan among the two main blades forming the space between the blades. It is composed of a plurality of first wing pieces arranged in a first region straddling the corresponding portions and a plurality of second wing pieces arranged outside the first region in the ring.
A cooling fan for a construction machine, wherein the plurality of first wing pieces are formed in a shape that relieves stress generated in a joint portion with the ring, as compared with the plurality of second wing pieces. In the cooling fan of the construction machine according to claim 1.
The first wing piece and the second wing piece each have a fillet at the root.
The first wing piece portion is a cooling fan for a construction machine, characterized in that the fillet portion thereof is configured to be larger than the fillet portion of the second wing piece portion. In the cooling fan of the construction machine according to claim 2.
The first wing piece and the second wing piece are configured to tilt backward with respect to the rotation direction of the cooling fan.
The fillet portion of the first wing piece portion and the fillet portion of the second wing piece portion are on the side surface of the first wing piece portion on the opposite rotation direction side and the second wing piece portion on the opposite rotation direction side, respectively. A cooling fan for construction machinery, which is characterized by being installed on the side. In the cooling fan of the construction machine according to claim 1.
The first wing piece portion is a cooling fan for a construction machine, characterized in that the first wing piece portion is formed in a shape having a smaller mass than the second wing piece portion. In the cooling fan of the construction machine according to claim 4.
The cooling fan of a construction machine, wherein the first wing piece portion is configured to have a thickness smaller than that of the second wing piece portion. In the cooling fan of the construction machine according to claim 4.
The first wing piece portion is a cooling fan for a construction machine , characterized in that the length in the radial direction is shorter than that of the second wing piece portion. In the cooling fan of the construction machine according to claim 4.
The first wing piece portion is a cooling fan for a construction machine , characterized in that the length in the axial direction is shorter than that of the second wing piece portion. In the cooling fan of the construction machine according to claim 1.
A cooling fan for a construction machine , characterized by having ribs connecting the plurality of first wing pieces. A cooling fan for construction machinery that is placed with a gap on the inner circumference side of the shroud.
With multiple main wings arranged at intervals in the circumferential direction,
A ring for connecting the outer peripheral end portions of the plurality of main wings is provided.
The plurality of wings are arranged so that at least one of the wings is wider than the other wings.
The ring has an enlarged diameter portion whose inner diameter and outer diameter expand in the discharge direction of the cooling fan, and the enlarged diameter portion is closer to the discharge side of the cooling fan than the shroud in the axial direction of the cooling fan. Arranged to be located,
A plurality of wing pieces arranged at intervals in the circumferential direction are further provided on the outer peripheral portion of the enlarged diameter portion of the ring.
The plurality of blade pieces are located between the wide blades in the ring and are located at the front edge of the main blade on the rear side in the rotation direction of the cooling fan among the two main blades forming the space between the blades. A cooling fan for a construction machine, characterized in that it is arranged in the entire circumferential direction of the ring except for a region straddling the corresponding portion .

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