JPH0478840B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an axial blower mounted on a speed sprayer or the like, and more particularly to an axial blower that reduces noise.

[Prior Art] FIG. 14 is an overall schematic diagram of an axial blower 12 mounted on a speed sprayer 10. The axial blower 12 is disposed at the rear of the speed sprayer 10, and includes a moving blade device 16 having a plurality of moving blades 14 arranged at equal angular intervals in the circumferential direction, and a plurality of stationary blades 18 arranged at equal angular intervals in the circumferential direction. and a stator vane device 20. The rotor blade device 16 and the stator blade device 20 are arranged side by side in the axial direction so that their center lines are the same.
is on the suction side, and the stator blade device 20 is on the discharge side, and the suction port of the moving blade device 16 is open toward the rear of the speed sprayer 10. In the case of the rear stator vane type, the output of the engine 22 is transmitted to the drive shaft 28 via the clutch 24 and the reducer 26, and the boss 30 of the rotor blade device 16 is integrally fixed to the rear end of the drive shaft 28. The rotor blades 14 are fixed to the circumferential surface of the boss 30 at the radially inner end of the axial blower 12. The hub 32 is disposed further rearward of the boss 30 and has a curved surface facing rearward. The fan case 34 surrounds the rotor blade device 16 and the stator blade device 20 on the outside in the radial direction, and the stator blade 18 includes:
It is fixed to the fan case 34 and the boss 36 at the radially outer and inner ends, respectively. The plurality of blow passages 38 extend in a curved manner from the discharge side of the stator vane device 20 and guide the wind from the axial blower 12 to the circumference of the speed sprayer 10 . The plurality of nozzles 40 are arranged at the downstream end of the ventilation passage 38,
The chemical liquid is fed under pressure from a power sprayer (not shown).

FIG. 15 shows the blade cross section 4 of the rotor blade 14 and stationary blade 18.
2 (a cross section of the rotor blades 14 and stator blades 18 taken in the circumferential direction of the axial blower 12). The chord length l is defined as a line segment connecting the leading edge and the trailing edge of the blade cross section 42, and the chord length center b is defined as the bisecting point of the chord length l.

FIG. 16 shows a cross section of each part (tip, average, and root) of the rotor blade 14 in a conventional axial blower 12 when viewed from the outside in the radial direction. Tip stagger αa, average stagger αb and root stagger αc
are the rotor blade tip cross section 44a and the rotor blade average cross section 44 with respect to the radial plane 46 passing through the center line of the rotor blade device 16.
b and a straight line drawn parallel to the chord length direction of each of the rotor blade root cross sections 44c. Stagger in the moving blade 14 increases from the root toward the tip. Conventional axial blower 12
Then, the chord length center b of the blade cross section 42 at each point in the radial direction of the axial blower 12 is the reference point, and the chord length center b as the reference point is a straight line ( (hereinafter referred to as a "radial straight line").
is fixed to the boss 30.

FIG. 17 shows a cross section of each part (tip, mean, and root) of the stationary blade 18 when viewed from the outside in the radial direction in the conventional axial flow blower 12. Tip stagger βa, average stagger βb and root stagger βc
is the stator blade tip cross section 48a with respect to the radiation plane 46,
Stator blade average cross section 48b and stator blade root cross section 48c
It is defined as the angle formed by a straight line drawn parallel to each chord length direction. The stagger in the stationary blade 18 decreases from the root to the tip. In the conventional axial blower 12, the chord length center b of the blade cross section 42 at each point in the radial direction of the axial blower 12
Each stator vane 18 is fixed to the boss 36 so that the chord length center b serving as the reference point is located on a radial straight line.

FIG. 18 is a diagram of a conventional axial flow blower 12 viewed from the stator vane device 20 side in the axial direction. 16th
As explained in Figures and Figure 17, the axial blower 1
Each rotor blade 14 and stationary blade 18 are fixed to the boss 30 and the boss 36 such that the chord length center b of the blade cross section 42 at each point in the radial direction of the rotor blade 14 is located on a radial straight line. The stagger in the stator blades 18 increases and decreases from the root to the tip, so if the chord length of each of the rotor blades 14 and the stator blades 18 is constant at the tip, average, and root, the axis of the axial blower 12 When viewed from the direction, the leading edge 5 of the rotor blade 14
0 and the trailing edge 52, as well as the leading edge 54 and the trailing edge 56 of the stator vane 18, are arranged such that the leading edge 54 and the trailing edge 56 of the stator vane 18 gradually move away from the radial plane 46 on both sides in the circumferential direction toward the radial outward side of the axial blower 12, and the radial plane 46. 46. The axial intersection angle γ is the edge of the rotor blade 14 and the stator blade 18 that are closer to the stator blade 18 and the rotor blade 14 in the axial direction of the axial blower 12, in this case, the trailing edge 52 of the rotor blade 14. and Shizuka 1
This is the angle at which the front edge 54 of 8 intersects when viewed from the axial direction of the axial blower 12. In the conventional axial blower 12, this axial direction intersection angle γ is a smaller value than in the present invention.

[Problem that the invention seeks to solve]

Conventional axial flow blowers produce a large amount of wind noise when ensuring a predetermined air volume.

An object of the present invention is to provide an axial blower that can reduce wind noise, which is noise generated when ensuring a predetermined air volume.

[Means for solving problems]

According to this invention, a rotor blade device and a stator vane device each having a plurality of rotor blades and a plurality of stator blades are arranged adjacent to each other in the axial direction with their center lines coincident, and the stator of the rotor blades is moved from the inside in the radial direction. The stator blade's stagger increases outwardly and decreases from the radially inner side to the outer side. The edges of the rotor blade and the stator blade that are farthest from the stator blade and the rotor blade in the axial direction, respectively, are located in a parallel plane that is parallel to a radial plane passing through the center line of the rotor blade.

[Effect]

The edges of the rotor blades and stator blades that are closer to the stator blade and the rotor blade, respectively, in the axial direction of the axial blower are referred to as the "near side edges," and The edge that is farthest from the stationary blade and rotor blade is defined as the "distal edge." The axial intersection angle γ is defined as the angle at which the adjacent side edges of the rotor blade and stationary blade intersect when viewed from the axial direction of the axial blower. As the intersection angle γ increases, i.e.
It has been found that as the angle approaches 45°, the noise decreases. The far side edge of the rotor blade and stator blade is located on a plane passing through the center line of the rotor blade, and the stagger of the rotor blade increases from the inside to the outside in the radial direction, and the stagger of the stator blade increases in the radial direction. The number decreases from the inside to the outside. Therefore, when viewed from the axial direction of the axial blower, the proximal edge of the rotor blade forms a plane parallel to the radial plane that passes through the distal edge of the rotor blade as it goes radially outward. , and the degree of separation is larger than in the conventional case. Also, when viewed from the axial direction of the axial blower, the proximal side edge of the stator blade passes through the far side edge of the stator blade and approaches a plane parallel to the radial plane, radially outward, and approaches.
This degree of proximity is greater than in the conventional case. As a result, the axial intersection angle γ, which is the angle at which the proximal edges of the rotor blade and the stator blade intersect when viewed from the axial direction of the axial blower, increases (becomes close to 45°).

〔Example〕

Hereinafter, the present invention will be described with reference to embodiments shown in the drawings.

FIG. 13 is a graph showing the relationship between the axial arrow intersection angle γ and the specific noise level. It can be seen that in the range of 0 to 45 degrees of the axial direction arrow intersection angle γ, the specific noise level decreases as the axial direction arrow intersection angle γ increases.

1 to 5 relate to a first embodiment of the invention.

FIG. 2 shows the positional relationship between the rotor blades 14 and the stator blades 18 in the air flow direction, and the rotor blade device 16 and the stator blade device 20 are located on the upstream and downstream sides, respectively, in the air flow direction, that is, the axial blower 12 are arranged on the suction side and the discharge side, respectively, in the axial direction (rear stator vane type).

FIG. 1 shows a cross-section of the corner points (tip, mean, and root) of the rotor blade 14 and stationary blade 18 when viewed from the outside in the radial direction in the axial blower 12. The tip stagger αa, the average stagger αb, and the root stagger αc are relative to the radial plane 46 (already defined in FIGS. 16 and 17) as a plane passing through the center lines of the rotor blades 14 and stationary blades 18, or to the radial plane The rotor blade tip cross section 44 with respect to a parallel plane 58 parallel to 46
a, rotor blade average cross section 44b and rotor blade root cross section 4
4c is defined as the angle formed by a straight line drawn parallel to each chord length direction. Moving blade 14 and stationary blade 1
The staggers in 8 increase and decrease from the root to the tip, respectively. The edges of the rotor blades 14 and the stator blades 18 that are closer to the stator blades 18 and the rotor blades 14, respectively, in the axial direction of the axial flow blower 12 are adjacent side edges; 12 in the axial direction, respectively.
8 and the edge farthest from the rotor blade 14 are respectively defined as the far side edge. However, in this embodiment (rear stator vane type), the proximal side edge and the far side edge of the rotor blade 14 are defined as the far side edge. A trailing edge 52 and a leading edge 50, respectively, and the proximal and distal edges of the vane 18 are leading edges 54 and trailing edges 56, respectively. The moving blade 14 has a leading edge 50 as a far side edge as a reference point, and the leading edge 50 as the reference point is located on a parallel plane 58 along a radial line of the axial blower 12 (passing through the center line of the axial blower 12). , a straight line extending in the radial direction), and its base end portion is fixed to the boss 30 . The stationary blade 18 has a rear edge 56 as a far side edge as a reference point, and the rear edge 56 as the reference point is located on a straight line parallel to the radial line of the axial blower 12 on a parallel plane 58. As such, the base end and the distal end are fixed to the boss 36 and the fan case 34, respectively.

3 and 4 are views of only the rotor blade device 16 and only the stator blade device 20 viewed from the discharge side in the axial direction, and FIG. It is a diagram seen from the side. The moving blade 14 and the stationary blade 18 have a leading edge 50 and a trailing edge 56 as far side edges, respectively, located on straight lines 59 and 60 parallel to the radial line on a parallel plane 58. The stagger of the rotor blade 14 increases from the inside to the outside in the radial direction, and the stagger of the stationary blade 18 decreases from the inside to the outside in the radial direction. When viewed from above, it is radially outwardly away from the radiation plane 46, and this distance is greater than in the conventional case (FIG. 3). In addition, the leading edge 5 of the stationary blade 18
4 approaches the radiation plane 46 radially outward when viewed from the axial direction of the axial blower 12, and the degree of approach is greater than in the conventional case (FIG. 4).
As a result, as shown in FIG. 5, the axial intersection angle γ, which is the angle at which the trailing edge 52 of the moving blade 14 and the leading edge 54 of the stationary blade 18 intersect when viewed from the axial direction of the axial blower 12, increases. (It will be close to 45°.)

6 to 10 relate to a second embodiment of the invention.

FIG. 7 shows the positional relationship of the rotor blades 14 and the stator blades 18 in the air flow direction. Blower 12
are arranged on the discharge side and suction side, respectively, in the axial direction (front stator vane type).

FIG. 6 shows a cross section of the corner points (tip, mean, and root) of the rotor blades 14 and stationary blades 18 in the axial blower 12 when viewed from the outside in the radial direction. Moving blade 14
The staggers in the stator blades 18 increase and decrease from the root to the tip, respectively. In this embodiment (front stator vane type), the proximal and far side edges of the rotor blade 14 are a leading edge 50 and a trailing edge 5, respectively.
2, and the proximal and far side edges of the vanes 18 are the trailing edge 56 and the leading edge 54, respectively. Moving blade 1
4 has a rear edge 52 as a far side edge as a reference point, and the rear edge 52 as a reference point is parallel to a parallel plane 58.
The base end portion is fixed to the boss 30 so as to be located on a straight line parallel to the radial line of the axial blower 12 at the top. The stationary blade 18 has a leading edge 54 as a far side edge as a reference point, and a leading edge 54 as a reference point.
The base end and the distal end are respectively fixed to the boss 36 and the fan case 34 so that the fan 4 is located on a straight line parallel to the radial line of the axial blower 12 on a parallel plane 58.

8 and 9 are views of only the stator vane device 20 and only the rotor blade device 16 viewed from the discharge side in the axial direction, and FIG. It is a diagram seen from the side.
The stationary blades 18 and the rotor blades 14 have a leading edge 54 and a trailing edge 52 as far side edges, respectively, located on a straight line parallel to the radial line of the axial blower 12 on a parallel plane 58. The stagger of the blades 18 decreases from the inside to the outside in the radial direction, and the stagger of the rotor blades 14 increases from the inside to the outside in the radial direction.
When viewed from the axial direction of 2, the radial plane 46 is approached radially outward, and the degree of approach is greater than in the conventional case (FIG. 8). Also, Act 14
When viewed from the axial direction of the axial blower 12, the leading edge 50 of the axial blower 12 is radially outwardly away from the radiation plane 46, and the degree of separation is greater than in the conventional case (FIG. 9). As a result, as shown in FIG. 10, the axial intersection angle γ, which is the angle at which the trailing edge 56 of the stationary blade 18 and the leading edge 50 of the rotor blade 14 intersect when viewed from the axial direction of the axial blower 12, increases. (It will be close to 45°.)

FIG. 11 shows the rotor blades 14 as viewed from the outside in the radial direction in a third embodiment of the rear stator vane type axial flow blower 12 in which the rotor blade device 16 is disposed on the suction side of the stator vane device 20. A cross section of each location (tip, average and root) is shown. The leading edges 50a, 50b, 50c and the trailing edges 52a, 52b, 52c respectively indicate the leading edge and the trailing edge of the rotor blade tip cross section 44a, the rotor blade average cross section 44b, and the rotor blade root cross section 44c. In this embodiment, the reference point and the leading edge 50a, 50b, 50c of the blade cross section 42 at each location of the rotor blade 14 in the radial direction of the axial blower 12 are as follows:
They are not located on the same radial line, and the closer the leading edge is to the tip, the further downstream in the air flow direction they are located. However, the leading edges 50a, 50b, 50c as the rear far side of the rotor blade 14 and as the reference point,
Since it is located on the parallel plane 58, the trailing edges 52a, 52b, 52c as the proximal edges of the rotor blade 14
is farther away from the parallel plane 58 or the radial plane 46 when viewed from the axial direction of the axial blower 12, and this degree of separation is larger than in the conventional case. As a result, the intersection angle γ of the rotor blade 14 and the stator blade 18 in the axial direction
increases (becomes close to 45°).

FIG. 12 shows a front stator vane type axial flow blower 12 in which a rotor blade device 16 is disposed on the discharge side of a stator vane device 20.
FIG. 5 shows cross sections of each part (tip, average, and root) of the rotor blade 14 when viewed from the outside in the radial direction in the fourth embodiment. In this embodiment, the blade cross section 4 at each location of the rotor blade 14 in the radial direction of the axial blower 12 is
2 as a reference point and a trailing edge 52a as a far side edge;
52b and 52c are not located on the same radial line, but are located closer to the trailing edge of the tip and upstream in the air flow direction. However, the trailing edge 52a as the far side edge of the rotor blade 14 and as a reference point,
52b and 52c are located on the parallel plane 58, so that the leading edge 50 as the proximal edge of the rotor blade 14
a, 50b, 50c are the axial flow blower 1 toward the tip side.
Parallel plane 58 or radial plane 4 when viewed from the axial direction of 2
6, and this degree of separation is larger than in the conventional case. As a result, the axial intersection angle γ of the moving blade 14 and the stator blade 18 increases (approaching 45°).

〔Effect of the invention〕

As described above, according to the present invention, in an axial flow blower in which the stagger of the rotor blade increases from the inside to the outside in the radial direction, and the stagger of the stator blade decreases from the inside to the outside in the radial direction, Since the far side edge of the rotor blade and the stator blade are located on a plane passing through the center line of the rotor blade, the proximal side edge of the rotor blade is the far side edge of the rotor blade when viewed from the axial direction of the axial blower. radially outward and away from a plane parallel to the radial plane passing through the area, the degree of separation is greater than in the conventional case, and the proximal side edge of the stator vane is located at the far side of the stator blade. Radially outwardly, the plane approaches the plane parallel to the radiation plane through the side edges, and this approach is greater than in the prior art. As a result, the axial intersection angle γ, which is the angle at which the proximal edges of the rotor blade and stationary blade intersect when viewed from the axial direction of the axial blower, increases (approaching 45°), and wind noise as noise increases. can be reduced.

[Brief explanation of the drawing]

1 to 5 relate to a first embodiment of the present invention, in which FIG. 1 is a cross-sectional view of each part of a moving blade and a stator blade when viewed from the outside in the radial direction in an axial flow blower, and FIG. The figure shows the positional relationship of the rotor blades and stator blades in the air flow direction, Figures 3 and 4 are views of only the rotor blade device and only the stator blade device viewed from the discharge side in the axial direction, and Figure 5 6 is a view of the rotor blade device and the stator blade device together viewed from the discharge side in the axial direction, FIGS. 6 to 10 relate to the second embodiment of the present invention, and FIG. Figure 7 is a diagram showing the positional relationship of the rotor blades and stator blades in the air flow direction, and Figures 8 and 9 are the stator blades. Figure 10 is a view of only the device and the rotor blade device viewed from the discharge side in the axial direction, Figure 10 is a view of both the stator blade unit and the rotor blade unit viewed from the discharge side in the axial direction, and Figure 11 is a view of the rotor blade unit as viewed from the discharge side. FIG. 1 is a diagram showing a cross section of each part of the rotor blade when viewed from the outside in the radial direction in the third embodiment of the axial blower disposed on the suction side of the stator vane device.
Figure 2 is a diagram showing a cross section of various parts of the rotor blade when viewed from the outside in the radial direction in a fourth embodiment of an axial flow blower in which the rotor blade device is disposed on the discharge side of the stator blade device; The figure is a graph showing the relationship between the axial arrow intersection angle γ and the specific noise level, Figure 14 is an overall schematic diagram of an axial blower mounted on a speed sprayer, and Figure 15 is a blade cross section of the rotor blade and stationary blade. Figure 1 showing
Figure 6 shows the cross section of each part of the rotor blade when viewed from the outside in the radial direction in a conventional axial flow blower.
Figure 18 shows a cross section of each stationary blade when viewed from the outside in the radial direction in a conventional axial flow blower.
The figure is a diagram of a conventional axial flow blower (rear stator vane type) viewed from the side of the stator vane device in the axial direction. 12... Axial blower, 14... Moving blade, 16...
Moving blade device, 18... Stator blade, 20... Stator blade device, 5
0, 54... Leading edge, 52, 56... Trailing edge, 58...
...parallel planes.

Claims (1)

[Scope of Claims] 1. A rotor blade device 16 and a stator blade device 20 each having a plurality of rotor blades 14 and a plurality of stator blades 18 are disposed adjacent to each other in the axial direction with their center lines coincident, and the rotor blades 14
In the axial flow blower 12, the stagger of the stator blades 18 increases from the inside to the outside in the radial direction, and the stagger of the stator blades 18 decreases from the inside to the outside in the radial direction. The stator blade 18 and the rotor blade 1 in the axial direction, respectively.
4. An axial flow blower characterized in that an edge farther from the moving blade 14 is located in a parallel plane 58 parallel to a radial plane passing through the center line of the rotor blade 14. 2 The rotor blades 14 and the stator blades 18 have edges that are farthest from the stator blades 18 and the rotor blades 14 in the axial direction, respectively.
Straight line 5 parallel to the radial line passing through the center line of 8
9. The axial blower according to claim 1, wherein the axial blower is located on the upper part of the axial flow fan.