CN201281043Y

CN201281043Y - Axial fan

Info

Publication number: CN201281043Y
Application number: CNU2008202015529U
Authority: CN
Inventors: 周拨; 姜凤华; 张敏; 程竑理
Original assignee: Guangdong Midea Electric Appliances Co Ltd
Current assignee: Midea Group Co Ltd
Priority date: 2008-10-07
Filing date: 2008-10-07
Publication date: 2009-07-29
Anticipated expiration: 2018-10-07

Abstract

The utility model relates to a cross flow fan, comprising a cross flow wind wheel, a chassis scroll casing and an air-out frame scroll casing; wherein, the cross sectional shape of the chassis scroll casing comprises a chassis drainage line, a rear guidance scroll casing curved line and a chassis air outlet mold line, the cross sectional shape of the air-out frame scroll casing comprises a scroll casing tongue part and a front guidance scroll casing form, and the distance value of the scroll casing tongue part and the outer edge of the blade of the cross flow wind wheel is change value parallel to the axial direction of a rotating shaft. The scroll casing tongue part (4) is made into teeth shape, corrugation shape or oblique deformation shape along the axial direction. The cross flow fan is changed along the axial direction by a scroll casing structure, and acts on with the wind wheel for producing inconsistent (trend) pressure pulsation along the axial direction, and inhibits higher ultra-harmonic components produced with the wind wheel, thus eliminating the harmonic waves which are contained in the noise and is changed into strident noise; meanwhile, the structure change of the axial direction of the cross flow fan can lead the axial flow in the flow field in the cross flow fan to inhibit the generation and development of end wall corner vortex and the vortex in the wind wheel clearance flow, thus improving the aerodynamic noise, improving the whole sound quality and controlling the noise level of the whole fan.

Description

A kind of cross flow fan

Technical field

The utility model is a kind of cross flow fan, belongs to the renovation technique of cross flow fan.

Background technique

Cross flow fan since under certain flow coefficient with respect to axial-flow blower and centrifugal blower, the stagnation pressure coefficient of generation is higher, its requirement for the wind wheel radial dimension very little (volume is little); Can select impeller length freely according to requirement to air quantity, and air-supply is evenly concentrated and the lower characteristics of noise, specific efficiency is on the low side mutually although it is with axial flow and centrifugal fan, but in low pressure ventilations such as household electric appliance, laser device ventilations occasion, and agricultural material the aspect such as is cleaned and has been obtained extensive use.Along with industrial production, science and technology, and people, reduce noise and have higher requirement for the external characteristics performance that improves cross flow fan the cleanliness of work and living environment and the raising of comfort level requirement.

Existing cross flow fan belongs to the impulse wheel of the speed that only produces basically in impeller, and this speed must just can be converted into static pressure in outlet volute, and its performance is decided by the design form of outlet volute to a great extent.And outlet volute generally can be divided into two-part, the spiral case that leads after the first, and it two is the related spiral cases of preceding snail tongue.Generally revise for the concentric circle in the center of circle on the project engineering for back guiding spiral case in order to cross flow fan eccentric vortex center of vorticity position (laboratory data affirmation).And for preceding snail tongue connection spiral case, divide from structure, can continue to be subdivided into volute tongue (being called for short the snail tongue here) and leading again to these two major components of spiral case; Wherein leading is one section great circle camber line or straight line consistent with flow direction to the spiral case molded lines, problem concentrates in the design for the snail tongue, at present on the engineering extensive use form certain envelope " pocket-type " scheme with impeller, adopt this kind snail tongue backflow can be limited in the narrow space.Snail tongue room size has a significant impact for external characteristics performance, the noise control of blower fan.Fan pressure head reduced when the tongue gap was big, and flow reduces, and noise diminishes; When the tongue gap reduced, fan pressure head raise, and it is big that flow becomes, and noise increases.

The noise source of cross flow fan mainly can be divided into two parts, first wideband turbulence noise by a narrow margin, and it two is channel noises (rotational noise) of the high amplitude of narrow-band.On the one hand channel noise is as cross flow fan main noise source, and the complexity of turbulent flow research has on the other hand determined at present research for the cross flow fan noise reduction how mainly to concentrate on the discrete channel noise spectrum.Application and research for the measure of discrete channel noise spectrum, consider with discrete two aspects of axial direction dislocation from the radial direction dislocation is discrete, mainly concentrate in the transformation to tubular wine wheel, adopt modular more piece wind wheel to misplace combination (the axial direction dislocation is discrete) except the facility and structural strength improvement of processing, can play the effect of discrete channel noise spectrum; Adopt the equidistant random distribution (the radial direction dislocation is discrete) of oblique blade (axial direction dislocation discrete) and blade, compare, also effective discrete channel noise with the relevant equidistant prismatic blade that has strengthened the fundamental frequency pulsation of harmonic wave; Whether Chinese patent application number be to have put down in writing equidistantly or not blade hybrid mode noise reduction, equidistant tiltedly blade noise reduction, blade grouping in 99106786,95100629,00123848 respectively, and every group of blade evenly increases angle and arrange noise reduction.And, consider the duality and the spiral case molded lines two-dimensional design characteristic of cross flow fan internal flow for exploring by revising the approach of cross flow fan worm frame noise reduction, can suppress developing of turbulent flow by optimizing the design of spiral case molded lines, thereby improve noise level; But angle from the discrete channel noise spectrum, the two-dimensional design of spiral case molded lines obviously is not enough, need in the axial direction the spiral case molded lines to be designed again, consider the material impact of snail tongue to fan performance and noise control, thereby can at first transform in the axial direction the snail tongue, make it have the three dimensional design feature, be referred to as special-shaped snail tongue here.At present the snail tongue that adopts on the engineering mainly is the snail tongue of parallel rotary axes, and this snail tongue remains permanent distance with impeller outer edge in the axial direction, with " scraping " of wind wheel be permanent apart from linear type, be that two-dimentional spiral case molded lines designs the result of stretching vertically.Thereby near the snail tongue, adopt conventional rotor shaft upwards to be easy to generate the pressure pulsation of unanimity (trend), and therefore being easy to generate big higher harmonics composition, this harmonic wave has the characteristics that become the thorn power of hearing easily if be included in the noise.

The perseverance of using is apart from the cross flow fan of snail tongue (being referred to as straight line snail tongue) at present, and flow becomes big when reducing along with the tongue gap, but the also corresponding increase of noise.

The model utility content

The purpose of this utility model is to consider the problems referred to above and a kind of external characteristics performance of improving cross flow fan is provided, and reduces the cross flow fan of noise.

The technical solution of the utility model is: include tubular wine wheel, chassis spiral case, outlet frame spiral case, wherein the sectional shape of chassis spiral case includes chassis drainage thread, back guiding spiral case curve and chassis exhaust outlet molded lines, the sectional shape of outlet frame spiral case comprises volute tongue and leading to volute type, and volute tongue is being parallel on the axial direction of running shaft and the distance value between the impeller outer edge of tubular wine wheel is a changing value.

Above-mentioned volute tongue is axially being made dentation, corrugated or oblique twisted shape.

The utility model is owing to adopt volute tongue being parallel on the axial direction of running shaft and the distance value between the impeller outer edge of tubular wine wheel is the structure of changing value, it mainly acts on is by the variation in the axial direction of snail tongue structure, with the wind wheel effect, produce the pressure pulsation of inconsistent (trend) in the axial direction, suppress big higher harmonics composition with the wind wheel generation, thereby reach elimination is included in the thorn power of hearing that becomes in the noise by this harmonic wave effect, changing by the cross flow fan axial arrangement simultaneously makes the axial flow of cross flow fan flow field to helping to suppress end wall corner whirlpool, vortex in the stream of wind wheel gap etc. produces and development, play and improve the aerodynamic noise effect of (mainly referring to turbulence noise), finally improve the tonequality of complete machine, the noise level of control complete machine.The utility model is that a kind of design is ingenious, function admirable, convenient and practical cross flow fan.

Description of drawings

Fig. 1 is an idle call cross flow fan air channel two-dimension plane structure schematic representation.

Fig. 2 is the structural representation of spiral case in Fig. 1 structure.

Fig. 3 joins conventional straight snail tongue A1 or the oblique snail tongue A2 structural representation of abnormity for cross flow fan single-unit wind wheel.

Fig. 4-1 is that A among Fig. 3 is to view.

Fig. 4-2 is that B among Fig. 3 is to view.

Fig. 5-1 is the structural drawing of the utility model embodiment piano keys type abnormity snail tongue.

Fig. 5-2 is the sectional view of piano keys type abnormity snail lingual groove groove among Fig. 5-1.

Fig. 6 is the jagged structural drawing of the utility model embodiment abnormity snail tongue.

Fig. 7 is the jagged structural drawing of another special-shaped snail tongue of the utility model embodiment.

Embodiment

Embodiment:

The structural representation in idle call cross flow fan air channel comprises the air-inlet grille 15 that the intake grill place is provided with as shown in Figure 1, and the chassis 12 in addition that links to each other with air-inlet grille is pressed close to the position air-inlet grille 15 and is provided with the bar folding shape vaporizer 16 that supports by the chassis.Air from air-inlet grille 15 enters behind bar folding shape vaporizer, traverses cross flow fan 11, is sent to indoor environment by 14 guiding of blinds wind deflector again.The position that links to each other with the blinds wind deflector near wind wheel is provided with outlet frame 13 and wind deflector supporting bar 14, cross flow fan 11 includes tubular wine wheel 21, chassis spiral case 22, outlet frame spiral case, wherein the sectional shape of chassis spiral case includes chassis drainage thread 1, back guiding spiral case curve 2 and chassis exhaust outlet molded lines 3, the sectional shape of outlet frame spiral case mainly comprises volute tongue 4 and leading to volute type 5, and volute tongue 4 is being parallel on the axial direction of running shaft and the distance value between the impeller outer edge of tubular wine wheel is a changing value.

The utility model is not done simple axial tension on the basis of cross flow fan two dimension spiral case molded lines design, but makes the air channel design have more three-dimensional feature, considers the variation of axial flow; Particularly complete machine performance and noise are controlled the snail tongue portion that material impact is arranged, adopt change snail tongue technology (being referred to as special-shaped snail tongue here) in the axial direction, it is not the result that two-dimentional spiral case molded lines designs simple tension vertically that the utility model adopts the snail tongue, be parallel to running shaft to remain the structure of permanent distance different with impeller outer edge in the axial direction with traditional, above-mentioned volute tongue 4 is axially making special-shaped states such as dentation, corrugated or oblique twisted shape, as Fig. 5-1, Fig. 5-2, Fig. 6, shown in Figure 7.Fig. 3, Fig. 4 are the comparative example of conventional straight snail tongue and a kind of simple oblique axial form of snail tongue, and Fig. 3 joins the structural representation of conventional straight snail tongue A1 or the oblique snail tongue A2 of abnormity for cross flow fan single-unit wind wheel.In the present embodiment, the long 740mm of fuselage; Wind wheel is made up of 35 blades, and its physical dimension is 93mm (diameter) * 580mm (wind wheel is long); Tiltedly the tilt angle of blade is 5 degree; Former snail tongue room is 7.5mm, and tiltedly snail tongue room scope is 4mm～10mm; High wind shelves wind speed round 1050rpm.It mainly acts on, by the variation in the axial direction of snail tongue structure, with the wind wheel effect, produce the pressure pulsation of inconsistent (trend) in the axial direction, suppress big higher harmonics composition with the wind wheel generation, thereby reach elimination is included in the thorn power of hearing that becomes in the noise by this harmonic wave effect, changing by the cross flow fan axial arrangement simultaneously makes the axial flow of cross flow fan flow field to helping to suppress end wall corner whirlpool, vortex in the stream of wind wheel gap etc. produces and development, play and improve the aerodynamic noise effect of (mainly referring to turbulence noise), finally improve the tonequality of complete machine, the noise level of control complete machine.

The utility model is owing to make the axial flow of cross flow fan flow field to helping to suppress the gathering of low energy fluid at the end wall place by the variation of cross flow fan axial arrangement, control obstruction owing to end wall corner whirlpool, whirlpool, gap, passage whirlpool etc. produce and development produces runner, thereby reach the raising air quantity, improve the external characteristics performance of blower fan integral body.

It is that a kind of design is unique that the utility model adopts the cross flow fan of special-shaped snail tongue, the external characteristics function admirable, and tonequality and noise controlling level are preferable is used for low pressure ventilations ventilation occasions such as household electric appliance, laser device, and agricultural material such as cleans at the mechanism of aspect.

Claims

1, a kind of cross flow fan, include tubular wine wheel, chassis spiral case, outlet frame spiral case, wherein the sectional shape of chassis spiral case includes chassis drainage thread (1), back guiding spiral case curve (2) and chassis exhaust outlet molded lines (3), the sectional shape of outlet frame spiral case comprises volute tongue (4) and leading to volute type (5), it is characterized in that volute tongue (4) is being parallel on the axial direction of running shaft and the distance value between the impeller outer edge of tubular wine wheel is a changing value.

2, cross flow fan according to claim 1 is characterized in that above-mentioned volute tongue (4) axially making dentation, corrugated or oblique twisted shape.