Connecting structure of wind wheel and shaft of centrifugal fan

Abstract

The utility model relates to a centrifugal fan wind wheel and shaft connecting structure which comprises a wind wheel and a rotating shaft, one end of the rotating shaft is embedded in a support center block of the wind wheel, a plurality of protrusions distributed in the inclined direction are arranged on the circumferential face of the rotating shaft located on the support center block, and inclined grain knurling-shaped inlay bodies are formed. The inlay is located between the axial end of the rotating shaft and the main body end, the upper plane of the axial end of the rotating shaft is lower than the upper plane of the support center block, the end, with the inlay, of the rotating shaft and the support center block are fixed in an integrated injection molding mode, and a reinforcing boss is integrally formed on the lower plane of the support center block in an injection molding mode; according to the utility model, the wind wheel and the shaft body can be prevented from loosening, and the wind wheel can be prevented from being separated from the shaft body.

Description

Technical Field

[0001] The utility model belongs to the technical field of centrifugal fans, and in particular relates to a centrifugal fan impeller and shaft connection structure. Background Art

[0002] Existing air-cooled refrigerators all have centrifugal fans. Centrifugal fans are based on the principle of converting kinetic energy into potential energy. They use a high-speed rotating wind wheel to accelerate the gas, then slow down and change the flow direction, so that the kinetic energy is converted into potential energy (pressure). The wind wheel is in high-speed rotation during the conversion process, and the wind wheel is connected to the rotating shaft of the centrifugal fan. The current connection between the rotating shaft and the wind wheel is detachable or integrally injection-molded. Because the wind wheel rotates at high speed during operation, the existing detachable connection is easy to loosen and cause the centrifugal fan to fail. The integral injection-molded connection is because the circumferential surface of the rotating shaft is directly injection-molded with the wind wheel. Since the temperature of the refrigerator is relatively low and the rotating shaft is made of metal material and the wind wheel is made of plastic material, the wind wheel and the rotating shaft are easy to loosen over time, causing the centrifugal fan to fail. In addition, during the high-speed rotation of the wind wheel, a groove is excavated or an edge is milled on one side of the circumferential surface of the rotating shaft. In this way, the contact surface with the wind wheel after injection molding is too small, and the wind wheel will be separated from the shaft body over time. Summary of the invention

[0003] The utility model aims to overcome the deficiencies of the prior art and to provide a centrifugal fan impeller and shaft connection structure, which can prevent the impeller from loosening from the shaft and the impeller from separating from the shaft.

[0004] The purpose of the utility model is achieved through the following technical scheme. The centrifugal fan impeller and shaft connection structure comprises a impeller and a rotating shaft, one end of the rotating shaft is embedded in the bracket center block of the impeller, and the circumferential surface of the rotating shaft located on the bracket center block is provided with a plurality of obliquely distributed protrusions and an inlay forming a twill knurled shape, and the inlay is located between the axial end and the main body end of the rotating shaft, the upper plane of the axial end of the rotating shaft is lower than the upper plane of the bracket center block, the rotating shaft end with the inlay is fixed to the bracket center block by integral injection molding, and the lower plane of the bracket center block is integrally injection molded with a reinforcing boss.

[0005] The beneficial effects of the utility model are as follows: compared with the prior art, a twill knurled inlay is provided on the circumferential surface of one end of the rotating shaft and is fixed to the center block of the bracket by integral injection molding. The molding of the inlay makes the contact surface with the wind wheel after injection molding a full circumferential surface, and the embedded contact surface is greatly increased, so that no loosening will occur in any part of the embedded place, and the upper plane of the axial end of the rotating shaft is lower than the upper plane of the center block of the bracket, so that the rotating shaft is located below the injection molded body of the center block of the bracket, and the axial movement of the rotating shaft is controlled. At the same time, by providing a reinforcing boss, the force stability of the center block of the bracket is better; the above-mentioned arrangement can prevent loosening between the wind wheel and the rotating shaft, and the occurrence of the wind wheel detaching from the shaft body.

[0006] Preferably, the diameter of the inlay is smaller than the diameter of the rotating shaft, and the diameter difference between the two is 3 to 5 mm. Through such a diameter difference design, the contact surface of the center block of the bracket is larger and the anti-loosening is better during the integral injection molding process with the inlay. At the same time, the anti-pull-out between the axial surface of the inlay of the rotating shaft and the center block of the bracket is also better.

[0007] Preferably, the height h of the inlay is 1 / 3 to 1 / 2 of the height H of the support center block; through the arrangement of the above structure, the inlay is fully covered in the support center block, so that the inlay has a better anti-loosening effect in the support center block.

[0008] Preferably, the protrusions are obliquely distributed along the rotation direction of the rotating shaft, and adjacent protrusions are distributed at equal intervals; through the arrangement of the above structure, the anti-loosening force between the rotating shaft and the center of the bracket is made more uniform.

[0009] Preferably, the cross-section of the protrusion is an isosceles trapezoid, and the length of the lower base of the protrusion is 3 to 5 times the length of the upper top; this can prevent the protrusion from biting better between the centers of the brackets, and with such a structural arrangement, the protrusion has better stability against breaking at the low temperature of the refrigerator.

[0010] Preferably, the reinforcing boss is arranged in an inverted isosceles trapezoidal shape along the axial direction of the central block of the bracket; the reinforcing boss arranged in the shape of an isosceles trapezoid saves materials and facilitates demoulding while meeting the strength requirements, thereby greatly reducing costs.

[0011] Preferably, one or two annular grooves are provided on the circumferential surface of the main body end of the rotating shaft, the annular grooves are located on the side of the reinforcing boss, and the annular grooves and the reinforcing bosses are fixed by integral injection molding; by providing the annular grooves, loosening between the wind wheel and the rotating shaft is further prevented, so that loosening between the wind wheel and the rotating shaft is doubly prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the main cross-sectional structure of the centrifugal fan impeller and shaft connection structure of the utility model.

[0013] Figure 2 yes Figure 1 A is an enlarged structural diagram of FIG.

[0014] Figure 3 It is a schematic diagram of the three-dimensional structure of the rotating shaft of the utility model.

[0015] The numbers in the accompanying drawings are: 1. wind wheel; 2. rotating shaft; 3. bracket center block; 4. inlay; 5. reinforcing boss; 6. circumferential groove; 21. axial end; 22. main body end; 41. protrusion. DETAILED DESCRIPTION

[0016] The following is a detailed introduction to the utility model in conjunction with the accompanying drawings: Figures 1 to 3 As shown, the utility model includes a wind wheel 1 and a rotating shaft 2, one end of the rotating shaft 2 is embedded in the bracket center block 3 of the wind wheel 1, and a plurality of obliquely distributed protrusions 41 are provided on the circumferential surface of the rotating shaft 2 located on the bracket center block 3 to form an inlay 4 in the shape of a twill knurling, and the inlay 4 is located between the axial end 21 and the main body end 22 of the rotating shaft 2, the upper plane of the axial end 21 of the rotating shaft 2 is lower than the upper plane of the bracket center block 3, the end of the rotating shaft 2 with the inlay 4 is fixed to the bracket center block 3 by integral injection molding, and the lower plane of the bracket center block 3 is integrally injection molded with a reinforcing boss 5. The above-mentioned structure has the following advantages: when the temperature of the refrigerator is low and the rotating shaft is made of metal and the wind wheel is made of plastic, the wind wheel and the rotating shaft may become loose over time, which may cause the centrifugal fan to fail. The rotating shaft 2 is provided with a twill knurled inlay 4, so that the rotating shaft and the wind wheel 1 are in full circumferential embedded injection molding contact. Therefore, even if a certain part is tempered when the temperature of the refrigerator is low, it will not cause the rotating shaft and the wind wheel to loosen or fail all at once.

[0017] The diameter of the inlay 4 is smaller than the diameter of the rotating shaft 2, and the diameter difference between the two is 3 to 5 mm.

[0018] The height h of the inlay 4 is 1 / 3 to 1 / 2 of the height H of the stent central block 3 .

[0019] The protrusions 41 are distributed obliquely along the rotation direction of the rotation shaft 2 , and adjacent protrusions 41 are distributed at equal intervals.

[0020] The cross section of the protrusion 41 is an isosceles trapezoid, and the length of the lower bottom surface of the protrusion 41 is 3 to 5 times the length of the upper top surface.

[0021] The reinforcing boss 5 is arranged in an inverted isosceles trapezoidal shape along the axial direction of the bracket center block 3 .

[0022] One or two circles of annular embedding grooves 6 are provided on the circumferential surface of the main body end 22 of the rotating shaft 2. The annular embedding grooves 6 are located on the side of the reinforcing boss 5, and the annular embedding grooves 6 and the reinforcing boss 5 are fixed by integral injection molding.

[0023] During the injection molding process of the utility model, the inlay 4 end of the rotating shaft is placed into the center block 3 of the bracket, and the inlay 4 and the annular embedding groove 6 are integrally injection-molded with the center block 3 of the bracket by an injection molding machine.

[0024] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A centrifugal fan impeller and shaft connection structure, comprising an impeller (1) and a rotating shaft (2), characterized in that: One end of the rotating shaft (2) is embedded in the support center block (3) of the wind wheel (1), and a plurality of obliquely distributed protrusions (41) are provided on the circumferential surface of the rotating shaft (2) located on the support center block (3) to form an inlay (4) in the shape of a twill knurling, and the inlay (4) is located between the axial end (21) and the main body end (22) of the rotating shaft (2), and the upper plane of the axial end (21) of the rotating shaft (2) is lower than the upper plane of the support center block (3), and the end of the rotating shaft (2) with the inlay (4) is fixed to the support center block (3) by an integral injection molding method, and the lower plane of the support center block (3) is integrally injection molded with a reinforcing boss (5).

2. The centrifugal fan impeller and shaft connection structure according to claim 1, characterized in that: The diameter of the inlay (4) is smaller than the diameter of the rotating shaft (2), and the diameter difference between the two is 3 to 5 mm.

3. The centrifugal fan impeller and shaft connection structure according to claim 1, characterized in that: The height h of the inlay (4) is 1 / 3 to 1 / 2 of the height H of the support center block (3).

4. The centrifugal fan impeller and shaft connection structure according to claim 1, characterized in that: The protrusions (41) are distributed obliquely along the rotation direction of the rotation shaft (2), and adjacent protrusions (41) are distributed at equal intervals.

5. The centrifugal fan impeller and shaft connection structure according to claim 1, characterized in that: The cross section of the protrusion (41) is an isosceles trapezoidal shape, and the length of the lower bottom surface of the protrusion (41) is 3 to 5 times the length of the upper top surface.

6. The centrifugal fan impeller and shaft connection structure according to claim 1, characterized in that: The reinforcing boss (5) is arranged in the shape of an inverted isosceles trapezoid along the axial direction of the bracket center block (3).

7. The centrifugal fan impeller and shaft connection structure according to claim 1, characterized in that: One or two annular embedding grooves (6) are provided on the circumferential surface of the main body end (22) of the rotating shaft (2), the annular embedding grooves (6) are located on the side of the reinforcing boss (5), and the annular embedding grooves (6) and the reinforcing boss (5) are fixed by integral injection molding.

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