JPS58117395A - Fan - Google Patents

Abstract

PURPOSE:To raise the efficiency of a fan, by reducing the pressure loss by forming inlet ports of fluid passages at the peripheral portion of an upper plate for the fluid passages in the manner that they are communicated with outlet ports of an impeller, and thereby smoothening the fluid flow of the impeller. CONSTITUTION:Since the inner and the outer peripheral portions of an outlet port 13 of an impeller are located in the same plane and the portions of an upper plate 15 for return passages 14a where no opening is formed are juxtaposed in parallel with each other, the velocity distribution of fluid at the outlet port 13 is rendered substantially uniform. The fluid is introduced separately into a plurality of inlet ports 18 formed in the upper plate 15 and passed through divided return passages 14a communicated with respective inlet ports 18. Here, since the velocity of fluid flow is reduced gradually toward the outlet ports and the fluid discharged to the outside from an outlet 19 while increasing the fan pressure, it is enabled to reduce the pressure loss of the fan.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cylindrical blower used in combustion equipment, household appliances, appliances, and the like.

As shown in Figure 1.2, a conventional blower of this type has an impeller (b) rotatably disposed inside a cylindrical casing (fa).
A plurality of blades (C) are uniformly formed radially between a disc-shaped upper plate (bl) and a lower plate (b2), and these upper and lower plates (bl) (M) and blades (C ) and the outer end diameter of the impeller (b) are formed to have the same dimensions, and the lower plate (b2) of the impeller (b)
The upper surface plate (d) of the return passage Td disposed close to the impeller (bl) is set to be equal to the outer diameter of the impeller (bl), and It has a structure in which an annular dihyuser space (e) is provided therebetween.

However, according to such a structure, after the airflow flowing out from the outlet of the impeller (b) collides with the inner peripheral surface of the casing (a), most of the velocity component in the circumferential direction is generated in the dihyuser space (el). Since the air flows as a flow and circulates within the annular dehydrator space, a large pressure loss occurs when it collides with the inner peripheral surface of the casing (aluminum), and the circulating airflow is caused by the inner peripheral surface of the casing (aluminum Friction loss occurs, and bending loss occurs because the radial velocity component must be directed in the axial direction in the line through which the air flow flows in the return path (al side).

Furthermore, even when flowing into the return passage (dl), a loss occurs due to a mismatch in the direction of the flow with respect to the entrance of the return passage, and the total blowing pressure of the impeller (al) is transferred to the return passage (d).
By the time it reaches the fan outlet [f], which communicates with There were drawbacks such as not being able to do so.

In order to eliminate such drawbacks, as shown in Fig. 3, a plurality of spiral passages k are formed in the annular space formed between the inner circumferential direction of the casing (al) and the outer circumferential open end of the impeller (bl). A blower has been proposed in which the upper opening ends of these passages (GL) are provided at predetermined intervals in the circumferential direction, and the upper opening ends of these passages (GL) are communicated with the outer periphery of the impeller (BL), and the lower opening ends thereof are communicated with the return passage side. There is.

However, according to such a structure, the spiral passage (
Since the starting end (g2) of the passage wall (gl) forming g) is tangentially close to the outer periphery of the impeller (b) rotating at high speed, the air flow from the impeller tb) is i'+iJ g
rX is momentarily cut off at the starting end (g2), and a siren sound with a frequency determined by the number of blades of the impeller (bl) and the rotation speed is generated, and the generation of this siren sound is suppressed. In addition, configuring the spiral passages (g) independently in each of the annular spaces would complicate the structure and require a larger casing fat. The area of the passage that can be formed is restricted and the flow velocity within the passage increases, and when the air volume exceeds a certain level, pressure loss increases within the spiral passage fgl, resulting in a decrease in fan pressure.

In addition, a blower has been devised that attempts to eliminate the 8i+ defects by improving the structure of the impeller, but simply changing the shape of the impeller to the car does not allow the pressure possessed by the impeller to flow through without loss. Since the ventilation path is not configured, no significant improvement can be achieved.

In order to eliminate such drawbacks of conventional blowers, the present invention converts the dynamic pressure caused by the flow at the impeller outlet into pressure within the passage from the impeller outlet to the fan outlet, thereby reducing most of the interlocking energy of the flow. More than recovering pressure without loss #
The present invention provides an air blower characterized by making it possible to significantly improve fan performance by 150% compared to the conventional one.

To explain an embodiment of the present invention with reference to the drawings, (1) is a cylindrical casing, and a large face plate (2) is integrally provided at the upper end of the casing, and an inlet port (3) is provided in the center of this large face plate (2). It is perforated. +41 is an electric motor placed above the suction port (3), which is attached to a support fitting (5) fixed to the large face plate (2), and which is attached to the lower end of its rotating shaft (6) inside the casing (1). The impeller (7) is fixed by a fixture (8).

This impeller (7) has an upper surface plate O1j provided with an inlet (9) communicating with the suction port (3:) in the center, and this upper surface plate 0.
A plurality of blades #( 2) are installed radially.

The lower plate (l (#) of the impeller (7) is formed to have a larger diameter than the lower plate 0, and is inclined in the same direction from the inlet (9) to the outer periphery. It is formed into a bowl shape that is curved downward, and the curved bottom end of the bowl is the bottom plate (qI).
An annular outlet (14) is formed that opens downward between the curved lower end and the outer peripheral end surface of the lower surface plate Q (1), and is located on the outer peripheral extension of the upper surface plate Q (1). A small gap exists between the curved lower end and the inner peripheral surface of the casing (1).

The blade G is formed in a planar arc shape, S-shape, or flat plate shape, and its upper and lower ends are connected to the upper and lower surface plates [1 (') of the impeller (7).
The top and bottom plates (Ha1 (11
), and its outer end is attached to the bottom plate a.
It extends one circle from η and is located in the annular exit α field.

04 is a return passage, the lower plate α℃ of the impeller (7) mentioned above.
A circular passageway upper plate installed horizontally with a small gap below o! 9, the passage bottom plate 0 o'clock arranged at a constant interval below this passage upper plate nQ, and the initial number of guide vanes σ force arranged radially between these passage upper plate Qfll and the bottom plate 0O. and a booster blade.

The return passage upper plate a0 has a plurality of return passages on its outer periphery facing the annular outlet α east of the impeller (7) with gaps therebetween and opening in the same axial direction as the annular outlet (end). A zero-population Enoki is provided, and the inner arc surface (18a) of this passage entrance (G) is
) of the lower plate αυ of the impeller (7), that is, the annular outlet a
It is provided on a vertical plane equal to the inner end surface of the impeller (7), and the outer end opening is the outer diameter of the upper surface plate QQ of the impeller (7), that is, the annular outlet α4.
Further, one side end surface (18b) is formed on the same curved end surface as the curve on the back side of the guide vane αη, and the other side end surface (18C) is provided on a vertical plane equal to the outer end surface of the guide vane αη. It is formed into a linear end face in the same direction as the radial direction or in a direction slightly inclined from the outer end position of the next guide vane αη adjacent to . Therefore, the number of the return passage entrance α hooks and the guide vane α force are the same, and during the opening in the circumferential direction at the outer peripheral end of the return passage entrance QE9, the adjacent guide vane (17J
07), which is equal to the dimension between the outer ends of 07). Also, at the entrance of this passage), 1 tl on both sides of
l (18b) (18C) are formed so that they do not coincide with the outer end of the blade @ at the outlet of the impeller (7) on the vertical plane, and the number of blades (2) of the impeller (7) and The generation of the siren sound is suppressed by creating a time lag in the generation of the siren sound whose frequency is determined by the product of the number of rotations.

Guide vane (17+ is the impeller (7) as shown in Figure 6)
is curved in a substantially circular arc shape in the rotational direction of the passage, and its inner end is located at the upper end opening of the return passage outlet provided in the center of the passage bottom plate θ frame, and the outer end is passed through the upper plate and the outer periphery of the bottom plate QQ. It is tightly fixed to the inner circumferential surface of the casing (1) integrally with the end face, and forms an independent return passage (14a) between adjacent guide vanes αηαη to eliminate circulation and deflection of the gas flow. .

Furthermore, the passage bottom plate Qf on which these guide vanes αη are erected
9 is gradually inclined downward from its outer circumferential end in the same direction as the exit of the return passage Q41, and the height of the guide vane ση is gradually lowered from the outer end to the inner end according to the inclination, thereby forming the bottom of the return passage Q41. By gradually increasing the return path α
It is formed in a shape that gradually reduces the flow velocity at step 4, converts the interlocking energy of the flow into pressure, and recovers the pressure.

Note that the integration of the guide vane qno and the return passage upper plate Qf9 is achieved by means of a locking pawl (1) protruding from the upper end of these guide vanes αη.
An engagement hole (N4 in , 4η) drilled in the return passage upper plate Q
Although not shown, the lower end of the guide vane αη is also fixed to the return passage bottom plate OQ with the same structure.

) is a booster blade piece, whose L end is integrally connected to the inner end arc surface (13a) of each passageway population Q8J of the return passageway upper plate (to), and is downwardly connected to the return passageway upper plate OFj. It is formed by hanging at a right angle, and its - side end surface is brought into close contact with the back surface of the guide vane aη over the entire height to form a passage concentric with the inner circumferential surface of the casing (1) in a part of the return passage C141. death,
This is to recover the pressure of the flow from the passage entrance (toward) of the passage upper plate α type.

This booster blade piece (2) is preferably provided at a position with a radius approximately equal to the outer diameter of the impeller lower surface plate 0η, and its length and width in the direction of passage are also in the direction of passage [] (g). Don Sano 60~
A length of 85% maximizes the pressure recovery effect.

To describe the operation of the embodiment configured as described above, when the electric motor (4) is started and the impeller (7) is rotated, the airflow flows from the inlet (3) to the inlet (9) of the impeller (7). ),
The pressure increases due to the pressure increase action of the blades, and the flow flows in the centrifugal direction, and the flow is electrified downward (axially) by the curved portion of the upper surface of the impeller (7) and the outer peripheral cylinder of the OU. It flows out from the impeller exit.

The flow velocity distribution at the impeller outlet 03 is such that the inner and outer circumferential edges of the outlet α are on the same plane, and the unopened portions of the return passage upper plate are arranged parallel to each other in close proximity. The flow becomes approximately uniform, and the flow is divided into a plurality of passage entrances bored in the return passage upper plate Ql, and flows into the divided return passage (14a) that communicates with each passage entrance (end). do.

Since a booster blade piece (c) is provided that protrudes from the outer surface of the inlet portion of each return passageway (14a), the airflow flowing into the return passageway (14a) is caused by this booster blade. It flows along one side and is rectified to become a uniform flow and its flow velocity decreases, and the pressure corresponding to the amount of decrease is recovered and the pressure is increased.

In addition, the depth and height of each return passageway (14a) extends from the passageway entrance (G) and forms an expanding passageway that gradually increases in size, so that the flow velocity from the passageway population 08 is The fan pressure can be increased by gradually decelerating the speed energy and recovering the pressure, and the fan pressure is discharged from the passage outlet 09.

Furthermore, in this embodiment, the passage bottom plate Oo is inclined downward from the outer end toward the center in the flow direction, so that the flow can exit the passage smoothly without colliding strongly with the passage bottom plate OQ or being greatly restricted. It can flow up to the OI and reduce pressure loss.

Figure 6 shows a comparison of the pressure-air volume characteristics when the blower of the present invention and a conventional blower are manufactured with the same dimensions and operated at the same rotation speed, and the solid line indicates one example of the present invention. The broken line represents the fan characteristics of a conventional blower.

As is clear from this figure, according to the air blower of the present invention, the fan pressure is 1.5 times that of the conventional air blower,
It is possible to achieve high pressure.

As described above, the present invention includes an impeller rotatably disposed within a casing, and a plurality of guide vanes curved in a substantially arc shape between a passage top plate and a passage bottom plate, which are placed close to the bottom of the impeller. A return passage is provided in a radial manner, and a passage entrance communicating with the impeller outlet is provided on the outer periphery of the upper plate of the return passage, and a fan outlet is opened in the center of the passage bottom plate. Since this relates to a blower in which a booster blade piece is arranged on the six-curved side of the guide blade, a passage upper plate is arranged close to the blade piece, and the impeller outlet is placed on the outer periphery of this passage upper plate. Since there is a passage entrance that communicates with the impeller, the flow from the impeller quickly and smoothly flows into the passage entrance, preventing flow leakage or circulation, and preventing the flow from colliding with the inner peripheral surface of the casing. It does not cause any loss due to friction or friction with the wall surface, and therefore, it greatly reduces the H2 loss and makes it possible to blow air with high efficiency.

In addition, since the outlet of the impeller is parallel to and opposed to the entrance of the return passage, and the starting end of the passage can be eliminated, the generation of siren noise can be almost completely eliminated. The structure can be formed so that leakage of flow can be prevented by making it close to the inner circumferential surface of the casing with a narrow gap between the two, and the structure can be simplified.

Furthermore, in the present invention, the guide vanes arranged radially in the return passage are curved in a substantially arc shape, and the booster vane pieces are arranged on the six-curved side of the guide vanes, so that the airflow flowing into the return passage is directed to the booster vanes. The blade rectifies the flow into a uniform flow, reduces the flow velocity, and recovers the pressure to increase the pressure.The guide vanes also allow the fan pressure to be smoothly guided to the outlet of the passage, greatly increasing the fan pressure. be.

[Brief explanation of the drawing]

Figure 1 is a partially cutaway perspective view of a conventional blower;
The figure is a simplified cross-section m1, and the third meat is the same (a different feed ill from the conventional example). 4 is a partially cutaway perspective view showing an embodiment of the present invention, FIG. 5 is an exploded perspective view showing the components of the return passage, and FIG. 6 is a perspective view showing the embodiment of the present invention. It is a P-Q characteristic diagram with a conventional blower. (1) is the casing, (3) is the suction port, (4) is the electric motor, (7) is the impeller, (9) C-year-old population, (12 is the impeller, (
14 is the annular outlet, (14) is the return passage, OF, l is the passage top plate, QQ is the passage bottom plate, 0η is the guide vane, 01 is the passage entrance, (' is the passage exit. Patent attorney representing the patent applicant, Mt. Takashi Moto ゛Figure 1, Figure 3, Iris 5・g

Claims (1)

[Scope of Claims] ■ An impeller is rotatably disposed within the casing, and a plurality of guide vanes curved in a substantially arc shape are arranged radially between the passage top plate and the passage bottom plate in close proximity to the bottom of the impeller. A return passage number is fixedly provided in the upper plate of the return passage, and a passage entrance communicating with the outlet of the impeller X is opened on the outer periphery of the upper plate of the return passage, and a fan outlet is opened in the center of the passage bottom plate. A blower with a booster blade piece placed on the curved surface side of the guide blade. ■ The shape of the passage entrance that opens on the passage upper plate is such that the inner end surface is equal to the outer diameter of the lower plate of the impeller, the outer end surface is equal to the inner diameter of the casing, and one side end face is on the side of the curved surface of the guide vane. Claim 1, in which the other side end surface is equal to or slightly inclined in the radial direction from the same position as the outer end surface of the next guide vane in the rotational direction. The blower described in Ii+. ■ The blower according to claim 1 or 2, wherein the circumferential length of the booster blade piece disposed in the return passage is shorter than the minimum opening in the circumferential direction of the passage entrance. The blower according to claim 1, 2, or 3, wherein the pressure boosting blade piece disposed in the return passage is arranged at a position substantially equal to the outer diameter of the lower plate of the impeller. The impeller has an outer end projecting outward from the outer periphery of the lower plate between a circular flat bottom plate and a lower plate whose outer periphery is curved downward so that the outer periphery is located on the extension of the outer periphery of the lower plate. An air blower according to claim 1, 2, 3, or 4, wherein a plurality of blades are arranged in a radial manner.