JPH0538395U - Centrifugal multi-blade blower for automobile air conditioner - Google Patents

Abstract

(57) [Abstract] [Purpose] Preventing noise and abnormal noise from centrifugal multiblade blowers with a simple configuration. [Structure] A plurality of blades 2 are arranged around a rotating body 1 at a predetermined pitch P.
To form the fan 3, and to install the fan 3 in the case 4
In the centrifugal multi-blade blower for an air conditioner for an automobile housed in the fan scroll portion 5 of FIG. Of the winglets 2 are formed in a zigzag shape in the extending direction, and the distance L between the tips of the staggered throat portions is set to the set pitch P of the blades (n-
½) times (n is a natural number).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a centrifugal multi-blade blower, which prevents generation of abnormal noise and noise during operation.

[0002]

[Prior Art]

 An example of a centrifugal multiblade blower used in an air conditioner for an automobile is disclosed in Japanese Utility Model Laid-Open No. 60-192,912. As shown in FIGS. 6 and 7, in this centrifugal multiblade blower, a bell mouth 10 is provided on one side plate of the fan scroll portion 5 of the intake unit 15, and the wing piece 2 is provided on the other side plate. The fan motor 11 to which the fan 3 having is attached is fixed. Further, a concave portion 12 is formed in the central portion of the fan 3, and by accommodating a part of the fan motor 11 in the concave portion 12, the volume occupied by the entire intake unit is reduced. When the fan motor 11 operates and the fan 3 rotates, outside air or inside air is introduced from an intake (not shown), and this air passes through the bell mouth 10 and is blown from the suction portion 13 of the fan 3 to the discharge portion 14. . Thereafter, the intake air is blown to a cooler unit or a heater unit (not shown) connected to the intake unit 15 and is supplied as conditioned air into the vehicle compartment from each outlet.

[0003]

[Problems to be solved by the device]

 However, in the conventional centrifugal multi-blade blower, the fan blades 2 pass through the throat tip 16 of the fan scroll portion 5 (the portion where the gap between the fan and the fan scroll portion is the smallest). At this time, the air pressure at this portion rises, and after the wing piece 2 has passed through the slot tip 16, the air pressure falls. Therefore, when the centrifugal multi-blade fan 3 in which a large number of blades 2 are arranged at a predetermined interval rotates, the air pressure between the fan 3 and the throat tip 16 fluctuates periodically as shown in FIG. It was the cause of the abnormal noise.

The present invention has been made in view of the above problems of the prior art, and an object thereof is to prevent noise and abnormal noise of a centrifugal multiblade blower with a simple configuration.

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention forms a fan (3) by arranging a plurality of blades (2) around a rotating body (1) at a predetermined pitch (P). In the eccentric multi-blade blower for an air conditioner for automobiles, in which the fan scroll part (5) of the case (4) is housed, the gap between the fan scroll part (5) and the fan (3) is the largest. The throat end (6) of the narrow case is formed in a zigzag shape in the extending direction of the blade (2) of the fan, and the separation dimension (L) of each end of the throat part which is zigzag Is set to (n-1 / 2) times the set pitch (P) of the blades (n is a natural number), which is a centrifugal multi-blade blower for an air conditioner for an automobile.

[0006]

[Action]

 When the fan (3) housed in the fan scroll part (5) rotates, when the blade piece (2) passes through the tip (6) of the throat part where the gap between the fan scroll part and the fan is the smallest, The air pressure in the area rises, but after the winglet passes, the air pressure drops. Since this fan (3) has a plurality of blades (2) arranged at a predetermined pitch (P) around the rotating body (1), such air pressure fluctuations occur periodically. However, according to the centrifugal multiblade blower of the present invention configured as described above, the throat tip (6) is formed in a zigzag shape in the extending direction of the fan blade (2), and Since the separation dimension (L) at each tip of the staggered throat is (n-1 / 2) times the set pitch (P) of the winglets (n is a natural number), the peak value of air pressure is small. At the same time, the fluctuation cycle of the air pressure is also reduced, resulting in high-frequency noise, and as a result, the sound absorption processing becomes easy.

[0007]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a main part of a centrifugal multiblade blower according to an embodiment of the present invention, FIG. 2 is a plan view showing the same embodiment, and FIG. FIG. 4 is a graph showing a pressure fluctuation, and FIG. 4 is a conceptual diagram showing a specific example in which the centrifugal multiblade blower of the embodiment is applied to an air conditioner for an automobile.

First, as shown in FIG. 1, the fan 3 according to the present embodiment has a recess 12 for accommodating a part of the fan motor 11 formed in the center of the rotating body 1. It has a mold shape and its slope is formed so as to smoothly curve along the flow direction of intake air. Further, a plurality of blades 2 are arranged around the rotor 1 at a predetermined pitch P, and the air flowing from the suction portion 13 of the rotor 1 along the above-mentioned recess 12 is adjacent. It is discharged to the fan scroll portion 5 from the discharge portion 14 formed in the gap between the blade pieces.

The fan 3 configured as described above is attached to the rotation shaft of the fan motor 11, and is housed in the fan scroll portion 5 of the intake unit 15. The intake unit 15 is provided with an outside air intake 17 and an inside air intake 18, and an intake door 19 for selectively opening or closing either one is rotatably attached. Then, the air introduced from the outside air intake 17 or the inside air intake 18 is introduced into the suction portion 13 of the fan 3, flows along the concave portion 12, and is blown from the discharge portion 14 to the fan scroll portion 5. A cooler unit 21 incorporating the evaporator 20 is connected to the downstream side of the intake unit 15, and a heater unit 22 is connected to the downstream side of the cooler unit 21. The intake air discharged from the discharge unit 14 of the fan 3 is introduced into the heater unit 22 in a cooled or uncooled state when passing through the evaporator 20, and the heater core 23 installed in the heater unit 22 is introduced into the heater unit 22. The ratio of the amount of air passing through and the amount of air bypassing the heater core is adjusted by the opening degree of the mix door 24 rotatably mounted on the upstream side of the heater core. Then, after being mixed to a predetermined temperature in a mixing chamber 25 formed on the downstream side of the heater core 23, any one of the differential outlet 26, the vent outlet 27, and the foot outlet 28 provided in the heater unit is blown. It will be supplied from the exit into the passenger compartment.

In this embodiment, the slot portion 6 of the fan scroll portion 5 of the intake unit 15, that is, the portion where the gap between the fan 3 and the side wall of the fan scroll portion 5 is the smallest is shown in FIG. As shown in FIG. 2, the fan blades 2 are formed in a zigzag shape in the extending direction. In this throat portion 6, a step portion 29 is formed at a position corresponding to the center of the fan blade piece 2, and the upper and lower throat portion tips 6a and 6b defined by the step portion 29 are substantially parallel to the blade piece 2. Has become. The distance L between the upper tip 6a and the lower tip 6b of the throat portion is (n-1 / 2) times the set pitch P of the fan blade 2 described above. However, n is a natural number.

Next, the operation will be described. When the fan motor 11 is operated and the fan 3 rotates, the intake air introduced from the outside air intake 17 or the inside air intake 18 is introduced into the suction portion 13 of the fan. Then, this air is discharged from the discharge portion 14 of the fan to the fan scroll portion 5 due to the pressure difference between the inside and outside of the rotating blade piece 2, and flows down to the cooler unit 21 and the heater unit 22 connected to the intake unit 15. As the fan 3 rotates, when the blade 2 passes through the tip 6 of the throat portion where the gap between the fan scroll portion 5 and the fan 3 is the smallest, the air pressure at this portion rises, and After 2 passes, the air pressure will drop. Since the fan 3 has a plurality of blades 2 arranged around the rotating body 1 at a predetermined pitch P, such fluctuation of the air pressure occurs periodically. However, in the present embodiment, the throat tip ends 6a, 6b are formed in a zigzag shape in the extending direction of the fan blades 2, and the distance L between the tip ends 6a, 6b of the throat portion is zigzag. Is set to (n-1 / 2) times the set pitch P of the winglets 2 (n is a natural number). Therefore, as shown in FIG. 3, air pressure fluctuations caused by the upper tip 6a of the throat portion (see FIG. 3). (Shown by the solid line) and the air pressure fluctuation caused by the lower tip 6b of the throat portion (shown by the dotted line in FIG. 3) temporally phase with each other, and as a result, the peak value of the air pressure generated from the entire throttle portion 6 Becomes smaller and the period of fluctuation of air pressure becomes smaller, resulting in high frequency noise. Since such high frequency noise is easier to absorb with a sound absorbing material than low frequency noise, if a sound absorbing material is provided in the intake unit 15 or the like, noise generated from the throat portion 6 can be prevented. it can.

The present invention is not limited to the above-described embodiments, but can be modified in various ways. For example, in the above-described embodiment, the throat portion has a zigzag shape of two upper and lower stages, but it may have a zigzag shape of three or more stages as shown in FIG.

[0013]

[Effect of the device]

 As described above, according to the present invention, the tip of the throat portion of the case where the gap between the fan scroll portion and the fan is the smallest is formed in a zigzag pattern in the extending direction of the fan blades. Since the distance between each tip of the throat part, which is shaped like a circle, is set to (n-1 / 2) times the set pitch of the blade (n is a natural number), the noise and noise of the centrifugal multiblade blower can be simplified. Can be prevented.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a centrifugal multiblade air blower according to an embodiment of the present invention.

FIG. 2 is a plan view showing the same embodiment.

FIG. 3 is a graph showing pressure fluctuation at the tip of the throat according to rotation of the fan of the embodiment.

FIG. 4 is a conceptual diagram showing a specific example in which the centrifugal multiblade air blower of the embodiment is applied to an automobile air conditioner.

FIG. 5 is a perspective view of an essential part of another embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a conventional centrifugal multiblade blower.

FIG. 7 is a plan view showing a conventional centrifugal multiblade air blower of the same type.

FIG. 8 is a graph showing pressure fluctuations at the tip of the throat due to rotation of the fan of the conventional centrifugal multiblade blower.

[Explanation of symbols]

1 ... Rotating body, 2 ... wing piece,
3 ... Fan, 4 ... Case, 5 ... Fan scroll part, 6 ... Throat part tip, L ... Spacing size of each tip of throat part, P ... Set pitch of blade

Claims (1)

[Scope of utility model registration request] 1. A fan (3) is constructed by arranging a plurality of blades (2) around a rotating body (1) at a predetermined pitch (P), and the fan (3) is installed in a case (4). In a centrifugal multi-blade blower for an automobile air conditioner housed in a fan scroll section (5), a throat section of a case where the gap between the fan scroll section (5) and the fan (3) is the smallest. The tips (6) are formed in a zigzag shape in the extending direction of the fan blades (2) of the fan, and the spacing dimension (L) of the tips of the throat portion in the zigzag shape is set to the set pitch (P) of the blades. )
(N-1 / 2) times (n is a natural number) of the centrifugal multi-blade blower for an air conditioner for an automobile.