阅读说明：本技术 混流式叶轮 (Mixed flow type impeller ) 是由 高飞 谢志尧 谢智育 艾子铭 顾嘉林 高乙禾 周艾文 艾芷欣 廖俊杰 周金华 杨 于 2019-11-19 设计创作，主要内容包括：本发明公开一种混流式叶轮,其包括叶轮本体、叶轮罩及多个叶片,叶轮本体用于安装转轴；叶轮罩罩设于叶轮本体外并与之相间隔,且叶轮罩与叶轮本体之间形成流道,流道在混流式叶轮的截面上呈双曲梯形结构,且流道的面积沿流通路径方向呈线性递增、线性递减或均匀变化；多个叶片相间隔地设于叶轮本体、叶轮罩之间,且每一叶片在垂直于转轴的平面上的投影均呈旋转螺旋线型,可以提高流道的整体流动效率,使风压、流量、噪音均有明显改善,再者通过配合旋转出模工艺使整体滑块数量降低,大大简化模具结构,使成型精度提高,开模周期、费用与后续维修成本均有大幅降低。(The invention discloses a mixed flow type impeller, which comprises an impeller body, an impeller cover and a plurality of blades, wherein the impeller body is used for installing a rotating shaft; the impeller cover is arranged outside the impeller body and is spaced from the impeller body, a flow channel is formed between the impeller cover and the impeller body, the flow channel is of a hyperbolic trapezoid structure on the section of the mixed-flow impeller, and the area of the flow channel is linearly increased, linearly decreased or uniformly changed along the flow path direction; the blades are arranged between the impeller body and the impeller cover at intervals, and the projection of each blade on the plane perpendicular to the rotating shaft is in a rotating spiral line shape, so that the overall flow efficiency of a flow channel can be improved, the air pressure, the flow and the noise are obviously improved, the number of the overall sliding blocks is reduced by matching with a rotating mold discharging process, the mold structure is greatly simplified, the forming precision is improved, and the mold opening period, the cost and the subsequent maintenance cost are greatly reduced.)

1. A mixed-flow impeller, comprising:

the impeller comprises an impeller body, a rotating shaft and a bearing, wherein the impeller body is used for mounting the rotating shaft;

the impeller cover is arranged outside the impeller body and is spaced from the impeller body, a flow channel is formed between the impeller cover and the impeller body, the flow channel is of a hyperbolic trapezoid structure on the section of the mixed-flow impeller, and the area of the flow channel is linearly increased, linearly decreased or uniformly changed along the direction of a flow path;

the blades are arranged between the impeller body and the impeller cover at intervals, and the projection of each blade on a plane perpendicular to the rotating shaft is in a rotating spiral line shape.

2. The mixed-flow impeller of claim 1, wherein a flow channel inlet is formed between the impeller shroud and the top of the impeller body, a flow channel outlet is formed between the impeller shroud and the bottom of the impeller body, and the area of the flow channel inlet is greater than or equal to the area of the flow channel outlet.

3. The mixed-flow impeller of claim 2, wherein the ratio of the area of the flow channel inlet to the area of the flow channel outlet is S₁/S_nAnd 1 is equal to or less than S₁/S_n2 or less, wherein S1 is the area of the runner inlet, and S2 is the area of the runner outlet.

4. The mixed-flow impeller of claim 3, wherein the ratio S of the area of the flow channel inlet to the area of the flow channel outlet₁/S_n∈(1.3，2)。

5. The mixed-flow impeller according to claim 1, wherein a flow passage area S passing through any point on a center line of the flow passage in a flow path direction of the flow passage_i＝πr_il_iWherein r is_iIs the distance from a point on the center line of the flow channel to the axis of the rotating shaft, l_iIs the distance between the impeller shroud and the impeller body past this point.

6. The mixed-flow impeller according to claim 1, wherein a tip and a tail are formed at two ends of the blade, respectively, the tip is formed by extending the impeller body upwards towards the impeller shroud, the tip is parabolic, the bottom of the tip is lower than the top of the impeller body, and the top of the tip is lower than the top of the impeller shroud.

7. The mixed-flow impeller as claimed in claim 6, wherein the top of the impeller body is 1-15 mm lower than the top of the blade head in the axial direction of the rotating shaft.

8. The mixed-flow impeller as claimed in claim 7, wherein the top of the impeller body is 10-13 mm lower than the top of the blade head in the axial direction of the rotating shaft.

9. The mixed-flow impeller of claim 6, wherein said blade tail is serrated or wavy.

10. The mixed-flow impeller of claim 1, further comprising a housing mounted outside and spaced from the impeller shroud, and wherein the outer wall of the impeller shroud is spaced from the housing by less than or equal to 2.5 mm.

Technical Field

The invention relates to the technical field of impellers, in particular to a mixed flow type impeller capable of simplifying a mold and reducing the mold opening cost.

Background

The mixed flow impeller of manufacturing on the market at present generally adopts 9 straight wings or arc wing structures, but straight wing or arc wing structure are not conform to the requirement of rotatory flow pattern structure, it is mostly unordered runner that changes to make circulation channel in the leaf and wing section structure, and then lead to the flow of impeller, the wind pressure, performance such as noise is not good enough, furthermore, because the configuration needs to make the blade distortion, 9 leaf structures lead to the interval between the blade less simultaneously, consequently, it is very high to its mold processing requirement, this type of blade need adopt too much slider structure (slider quantity is about between 27 ~ 36) in production technology, lead to the mould structure complicated, the die sinking expense is high, the shaping precision is poor.

Therefore, there is a need to provide a mixed-flow impeller with good performance, which can simplify the mold and reduce the mold opening cost, so as to solve the above-mentioned problems in the prior art.

Disclosure of Invention

The invention aims to provide a mixed-flow impeller which has good performance, can simplify a mold and reduce the mold opening cost.

In order to achieve the purpose, the technical scheme of the invention is as follows: the mixed-flow impeller comprises an impeller body, an impeller cover and a plurality of blades; the impeller body is used for mounting a rotating shaft; the impeller cover is arranged outside the impeller body and is spaced from the impeller body, a flow channel is formed between the impeller cover and the impeller body, the flow channel is of a hyperbolic trapezoid structure on the section of the mixed-flow impeller, and the area of the flow channel is linearly increased, linearly decreased or uniformly changed along the direction of a flow path; the blades are arranged between the impeller body and the impeller cover at intervals, and the projection of each blade on a plane perpendicular to the rotating shaft is in a rotating spiral line shape.

Preferably, a flow channel inlet is formed between the impeller cover and the top of the impeller body, a flow channel outlet is formed between the impeller cover and the bottom of the impeller body, and the area of the flow channel inlet is greater than or equal to the area of the flow channel outlet.

Preferably, the ratio of the area of the flow channel inlet to the area of the flow channel outlet is S₁/S_nAnd 1 is equal to or less than S₁/S_n2, wherein, S1 is the area of runner import, S2 is the area of runner export, avoid accelerating too fast in the runner and produce extra flow resistance or slow down and produce the backward flow to improve runner circulation efficiency.

Preferably, a ratio S of an area of the flow channel inlet to an area of the flow channel outlet₁/S_n∈(1.3，2)。

Preferably, the center line of the flow passage is passed through in the direction of the flow path of the flow passageArea S of the flow path at any point_i＝πr_il_iWherein r is_iIs the distance from a point on the center line of the flow channel to the axis of the rotating shaft, l_iIs the distance between the impeller shroud and the impeller body past this point.

Preferably, the two ends of the blade form a blade head and a blade tail respectively, the blade head is formed by extending the impeller body upwards towards the impeller shroud, the blade head is parabolic, the bottom of the blade head is lower than the top of the impeller body, and the top of the blade head is lower than the top of the impeller shroud.

Preferably, the top of the impeller body is 1-15 mm lower than the top of the impeller head along the axial direction of the rotating shaft.

Preferably, the top of the impeller body is 10-13 mm lower than the top of the impeller head along the axial direction of the rotating shaft.

Preferably, the blade tail is zigzag or wavy.

Preferably, the mixed-flow impeller further comprises a casing, the casing is installed outside the impeller cover and spaced from the impeller cover, and the space between the outer wall of the impeller cover and the casing is less than or equal to 2.5 mm.

Compared with the prior art, the mixed-flow impeller has the advantages that the flow channel is formed between the impeller cover and the impeller body, the cross section of the flow channel on the mixed-flow impeller is of a hyperbolic trapezoid structure, and the area of the flow channel is linearly increased, linearly decreased or uniformly changed along the direction of a flow path; locate a plurality of blades looks interval the impeller body between the impeller casing, and each blade is at the perpendicular to projection on the plane of pivot all is rotatory helix type, consequently can improve the whole flow efficiency of runner, makes wind pressure, flow, noise all have obvious improvement, moreover makes whole slider quantity reduction through the rotatory process of drawing a mould of cooperation, has simplified the mould structure greatly, makes the shaping precision improve, and die sinking cycle, expense and follow-up cost of maintenance all reduce by a wide margin.

Drawings

Fig. 1 is a schematic structural view of a mixed-flow impeller according to an embodiment of the present invention.

Fig. 2 is a top view of fig. 1.

Fig. 3 is a front view of fig. 1.

Fig. 4 is a cross-sectional view of fig. 1.

Fig. 5 is an exploded view of fig. 1.

FIG. 6 is a top view of the impeller body and blades of FIG. 5.

FIG. 7 is a front view of the impeller body and blades of FIG. 5.

FIG. 8 is a schematic view of the flow path formed between the impeller body and the impeller shroud of FIG. 1.

Fig. 9 is a schematic view showing the linear change of the flow passage area in fig. 8 in the direction of the flow path.

Fig. 10 is a blade profile schematic view of the mixed-flow impeller of fig. 1.

FIG. 11 is a schematic structural view of an impeller body and blades of another embodiment of the mixed-flow impeller of the present invention.

Detailed Description

Embodiments of the present invention will now be described with reference to the drawings, wherein like element numerals represent like elements.

Referring first to fig. 1-8, an embodiment of a mixed-flow impeller 100 provided by the present invention includes an impeller body 110, an impeller shroud 120, and a plurality of blades 130. The impeller body 110 has a middle portion provided with a mounting portion 111 for mounting the rotating shaft, the mounting portion 111 is provided with a mounting hole, the cross section of the impeller body 110 is substantially a hyperbolic trapezoid structure (see fig. 4 and 8), specifically, the outer surface of the impeller body 110 is an arc structure and forms a first guide wall 112. The impeller cover 120 is covered outside the impeller body 110 and spaced from the impeller body 110, the top of the impeller cover 120 is higher than the top of the impeller body 110, the bottom of the impeller cover 120 is higher than the bottom of the impeller body 110 (see fig. 3-4), the inner surface of the impeller cover 120 is of an arc structure and forms a second guide wall 121, a flow channel 140 is formed between the second guide wall 121 and the first guide wall 112, and meanwhile, the area of the flow channel 140 is linearly increased, linearly decreased or uniformly changed along the airflow flowing direction so as to adapt to different requirements of acceleration, deceleration and uniform flow channels. The plurality of blades 130 are disposed between the first guide wall 112 and the second guide wall 121 at intervals, and each blade 130 extends spirally from the top of the impeller body 110 to the bottom thereof, so that a projection of each blade 130 on a plane perpendicular to the rotation axis is in a spiral shape (described in detail later).

Referring to fig. 4 and 8, in the present invention, the flow passage 140 has a hyperbolic trapezoid structure in a cross section of the mixed-flow impeller 100 (see fig. 8). Specifically, a runner inlet 141 is formed between the impeller body 110 and the top of the impeller cover 120, a runner outlet 142 is formed between the impeller body 110 and the bottom of the impeller cover 120, and the ratio of the area of the runner inlet 141 to the area of the runner outlet 142 is S₁/S_nWherein S is₁Is the area of the runner inlet 141, S_nThe area ratio S of the flow channel outlet 142₁/S_nPreferably in the range of 0.23 to 3.5, to form an accelerating, decelerating or uniform velocity flow channel.

With continued reference to FIGS. 4 and 8-9, in a more preferred embodiment of the present invention, the ratio S of the area of the channel inlet 141 to the area of the channel outlet 142₁/S_nPreferably in the range of 1. ltoreq.S₁/S_nLess than or equal to 2 to form equal acceleration or equal speed flow channel. In one of the most preferred embodiments, the area S of the channel inlet 141₁Greater than or equal to the area S of the flow channel outlet 142_nAnd, the ratio S of the areas₁/S_nThe flow channel 140 belongs to (1.3, 2), so that extra flow resistance caused by over-quick acceleration or backflow caused by deceleration in the flow channel 140 is avoided, the flow channel circulation efficiency is improved, flow loss is increased along the process of over-quick acceleration, and the backflow caused by deceleration causes the loss to be increased. Of course, S₁/S_nThe range is not limited to the above range.

Referring to fig. 4 and 8-9, a flow path direction F is formed from the runner inlet 141 to the runner outlet 142_mAlong the direction F of the flow path_mArea S of flow channel_iThe position in the flow channel is represented by the ratio of the length from any point on the center line of the flow channel 140 to the inlet 141 of the flow channel to the total length M of the flow channel 140, as shown in fig. 9. Specifically, in the flow path direction F_mThe area S of the flow path corresponding to any point on the center line of the flow path 140_i＝πr_il_iWherein r is_iIs the distance from the center point of the center line of the flow channel 140 to the axis A-A of the rotating shaft, l_iThe distance between the first guide wall 112 and the second guide wall 121 passing through the center point is shown in fig. 8. That is, the area S at the runner inlet 141₁＝πr₁l₁Wherein r is₁Is the distance from the central point of the channel inlet 141 to the axis A-A of the rotating shaft,/₁The distance between the first guide wall 112 and the second guide wall 121 passing through the center point; correspondingly, the area S at the flow channel outlet 142_n＝πr_nl_nWherein r is_nIs the distance from the central point of the channel inlet 141 to the axis A-A of the rotating shaft,/_nThe distance between the first guide wall 112 and the second guide wall 121 passing through the center point; area S₁To the area S_nIs uniformly changed.

More specifically, in the flow path direction F_mIn the above, the change rule of the flow channel area Si is linear change, specifically S_i＝k₁m_iWherein m is_iK1 is a constant value whose value is positively correlated with the acceleration/deceleration ratio, and k1 is a constant value when the total length M of the flow path 140 is determined to the area ratio of the flow path inlet 141 to the flow path outlet 142. In the present embodiment, k₁E (tan10 DEG, tan86 DEG), but the numerical value is not limited thereto.

More preferably, in the flow path direction F_mIn addition, the change rule of the flow passage area Si can adopt a complex fitting function form

Wherein (1 < k)₂≤6)。

Referring to fig. 4-7, a blade head 131 and a blade tail 132 are respectively formed at two ends of the blade 130, the blade head 131 is formed by extending the impeller body 110 upwards towards the impeller cover 120, and the blade head 131 is parabolic, so that the blade 130 is rotated and obliquely inserted to intake air, and the air intake capacity is increased; meanwhile, the bottom of the blade head 131 is lower than the top of the impeller body 110, so that a relatively large gap L (see fig. 4) is formed between the blade head 131 and the axis a-a, thereby forming an air suction channel between the blade heads 131 of the plurality of blades 130 and the axis a-a, the air suction channel is communicated with a channel between two adjacent blades 130, air is sucked and then is rotationally sent into the channel between the blades 130, and the distance h that the top of the impeller body 110 is lower than the top of the blade head 131 along the axis a-a direction is preferably 1-15 mm, so that an air inlet space is ensured, and air flow is smooth.

In a more preferred embodiment of the present invention, the distance h between the top of the impeller body 110 and the top of the blade head 131 along the axial direction is 10 to 13mm to ensure the above effect, but the distance is not limited thereto.

Referring to fig. 6 and 10, in the present embodiment, the projection of the profile of each vane 130 on the plane perpendicular to the axis a-a of the rotating shaft is a spiral, specifically, the profile of each vane 130 conforms to the profile of each vane 130

Rule, wherein the variable R_mIs the distance from any point on the blade profile line to the axis A-A of the rotating shaft, theta is the central angle of the point on the profile line and the starting point O of the blade profile line relative to the axis A-A of the rotating shaft, as shown in figure 10, k₃、k₅Is a labeled constant, and k₃≤r、k₅Less than or equal to 1.5, thereby reducing the loss of the flow channel 140, obviously improving the wind pressure, the flow and the noise and improving the whole flow efficiency of the flow channel 140.

Referring again to fig. 1-5, the mixed-flow impeller 100 of the present invention further includes a casing (not shown) installed outside and spaced apart from the impeller cup 120, and the interval between the inner wall of the casing and the outer wall of the impeller cup 120 is not more than 2.5mm, so as to suppress backflow and improve the overall flow efficiency. In the present embodiment, the interval between the inner wall of the casing and the outer wall of the impeller cup 120 is preferably set to be between 0.2mm and 1mm to ensure the above-mentioned effects. The structure and design of the housing are well known to those skilled in the art and will not be described in detail herein.

Referring now to fig. 11, in another embodiment of the mixed-flow impeller 100 of the present invention, the difference from the above embodiment is only that: the blade tail 132 of each blade 130 is zigzag or wavy to improve the speed distribution of the air outlet, uniformly exhaust air, miniaturize the wake vortex, and reduce the local noise caused by the secondary flow at the tail edge. The other structures are the same as those of the above-described embodiment, and the description thereof will not be repeated.

As shown in fig. 1 to 11, the mixed-flow impeller 100 of the present invention adopts a six-blade structure, and compared with the conventional nine-blade structure, the design of the airfoil structure of the flow channel 140 and the blades 130 is combined, so that the space between the blades 130 is increased, and the number of the integral slide blocks can be reduced to 0 to 6 by matching with the rotational mold-releasing process, which greatly simplifies the mold structure, improves the molding precision, greatly reduces the mold-releasing period, the cost and the subsequent maintenance cost, and greatly improves the production efficiency and the mold life because the number of the parts matched with the mold is reduced.

In summary, in the mixed-flow impeller 100 of the present invention, the area of the flow channel 140 formed between the impeller body 110 and the impeller shroud 120 is along the flow path direction F_mThe flow channel 140 is in a hyperbolic trapezoid structure in the cross section of the mixed-flow impeller 100, and the projection of each blade 130 on the plane perpendicular to the rotating shaft is in a spiral line shape, so that the overall flow efficiency of the flow channel 140 is improved, the air pressure, the flow and the noise are obviously improved, the number of the overall sliding blocks is reduced by matching with a rotary mold discharging process, the mold structure is greatly simplified, the forming precision is improved, and the mold opening period, the cost and the subsequent maintenance cost are greatly reduced.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the present invention, therefore, the present invention is not limited by the appended claims.