Method for producing a multi-sectioned cross-flow fan

Abstract

This invention discloses a method for producing a multi-section cross-flow fan, including a step of welding the middle sections of the fan. In this welding step, the inter-section deflection angle between each middle section is set to [(n-1) / 2]*360° / n, where n is the number of middle sections in the fan. This invention, through the establishment of a mathematical model, utilizes the principle that unbalanced quantities cancel each other out during the circular rotation of the cross-flow fan. Without significantly altering the fan's manufacturing process, and based on the premise of not relying on improved product molds and processing control, the method improves the welding process of the middle sections. By adjusting the inter-section deflection angle according to a specific formula, the overall dynamic balance level of the multi-section cross-flow fan is significantly improved. This effectively eliminates the inherent dynamic balance differences of the fan, as well as relatively stable dynamic balance differences within a certain processing time, without affecting completely random dynamic balance differences.

Description

Technical Field

[0001] This invention relates to the field of cross-flow fan technology, and in particular to a method for producing a multi-section cross-flow fan. Background Technology

[0002] Cross-flow fans are an important component of air conditioning indoor units, achieving airflow through their high-speed rotation. A typical cross-flow fan consists of an impeller and two end plates fixed to both ends of the impeller. The impeller itself is composed of welded sections with blades attached, hence it is also called a multi-section cross-flow fan.

[0003] During the production of cross-flow fans, dynamic balance deviations often exceed standards due to factors such as product structure, mold processing quality, production molding conditions, and fluctuations in the production environment. Currently, the common industry solution is to conduct dynamic balance tests and add balancing blocks for adjustment. However, these tests and adjustments consume significant manpower and resources, increasing the production cost of cross-flow fans. Furthermore, many factors contribute to excessive dynamic balance deviations in cross-flow fans, making it impossible to eliminate them all individually. This can significantly impact the entire production process, making it difficult to completely eradicate the problem at its source. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for producing a multi-section cross-flow fan, which can effectively improve the dynamic balance of the multi-section cross-flow fan through simple structural improvements.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for producing a multi-section cross-flow fan, including a step of welding the middle section of the multi-section cross-flow fan. In the welding step of the middle section of the multi-section cross-flow fan, the deflection angle between each middle section is set to [(n-1) / 2]*360° / n, with a tolerance range of ±10°, where n is the number of middle sections of the multi-section cross-flow fan.

[0006] As an improvement to the above solution, the following steps are included:

[0007] S1. Analyze the dynamic balance of the multi-section cross-flow fan, establish a mathematical model, use a circular model to represent the projection of the middle section of the multi-section cross-flow fan with the same structure, and use the radius line of the circle to represent the unbalance and direction of the multi-section cross-flow fan.

[0008] S2. Distribute the unbalance of the multi-section cross-flow fan across the entire circumferential model, observe the distribution of the unbalance, and adjust the distribution angle until the unbalance of the multi-section cross-flow fan is relatively evenly distributed on the circumferential model. Obtain the new inter-section deflection angle value and derive the calculation formula [(n-1) / 2]*360° / n.

[0009] S3. Analyze the partition balance of the multi-section cross-flow fan in the axial direction, establish a circular ring model, and use the radius and sphere to represent the unbalanced direction. Simulate the spatial arrangement of the multi-section assembly according to the inter-section deflection angle in step S2, observe the rotation dynamics of the sphere, and make the rotation of the sphere in the axial direction achieve a dynamic balance difference cancellation state.

[0010] S4. Analyze the blade overlap of the middle section of the multi-section cross-flow fan. First, compare the blade deflection positions of two consecutive middle sections, and then compare the blade deflection positions of all middle sections. The final solution is a design model that avoids blade overlap and avoids the blades being arranged in a completely balanced manner on the 360° circumference.

[0011] S5. Analyze the distribution of circumferential dynamic balance differences under the newly determined internode deflection angle to make the line distribution on the circular model relatively balanced, while the circumferential distribution of unbalanced lines on the circular model is not completely uniform.

[0012] S6. Determine the final design model and weld the middle section of the multi-section cross-flow fan.

[0013] As an improvement to the above scheme: the number of middle sections of the multi-section cross-flow fan is 13, and the deflection angle between the middle sections is 159°.

[0014] The beneficial effects of this invention are as follows: This invention analyzes the dynamic balance of multi-section cross-flow fans by establishing a mathematical model, matching it with the characteristics of cross-flow fan rotation. Utilizing the principle that unbalances cancel each other out during the circular rotation of the cross-flow fan, without significantly altering the production process of the cross-flow fan, and without relying on improved product molds and processing control, the invention improves the welding process of the middle section of the cross-flow fan. By adjusting the deflection angle between sections of the cross-flow fan according to a specific formula, the overall dynamic balance level of the multi-section cross-flow fan is significantly improved. This not only effectively eliminates the inherent dynamic balance differences of multi-section cross-flow fans but also eliminates relatively stable dynamic balance differences within a certain processing time period, without affecting completely random dynamic balance differences. Attached Figure Description

[0015] Figure 1 This is a schematic diagram showing the distribution of imbalance in a multi-section cross-flow fan on a circular model in the prior art.

[0016] Figure 2 This is a schematic diagram showing the distribution of unbalance in the multi-section cross-flow fan on a circular model in Embodiments 1 and 2 of the present invention;

[0017] Figure 3 This is a schematic diagram of the axial dynamic balance distribution of the multi-section cross-flow fan on the annular model in Embodiment 1 of the present invention;

[0018] Figure 4 This is a schematic diagram of the axial dynamic balance distribution of the multi-section cross-flow fan on the annular model in Embodiment 2 of the present invention;

[0019] Figure 5 This is a schematic diagram showing the overlapping deflection positions of the blades in two consecutive middle sections in Example 3;

[0020] Figure 6 This is a schematic diagram showing the overlapping of the blade deflection positions of all the middle sections in Example 3;

[0021] Figure 7 This is a schematic diagram of the distribution of unbalance in a circular model of a cross-flow fan with 13 middle sections. Detailed Implementation

[0022] To facilitate understanding of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0023] In the description of this invention, it should be noted that the terms "front", "rear", "left", "right", "up", "down", "inner", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0024] The production method of the multi-section cross-flow fan disclosed in this invention analyzes the dynamic balance of the multi-section cross-flow fan by establishing a mathematical model. It changes the existing method of small-angle welding deflection angle and adjusts the inter-section deflection angle to ensure it corresponds to the number of sections in the multi-section cross-flow fan. Specifically, it includes the following steps:

[0025] S1. Analyze the dynamic balance of the multi-section cross-flow fan and establish a mathematical model. Use a circular model to represent the projection of the middle section of the multi-section cross-flow fan with the same structure. Use the radius line of the circle to represent the unbalance and direction of the multi-section cross-flow fan. The distribution of the radius line on the circle indicates the distribution of the unbalance, and the direction of the radius line indicates the direction of the unbalance. If the radius line is more concentrated on the circular model, it indicates that the superposition of the unbalance is more serious. In actual products, this is reflected in the relatively concentrated and fixed area of ​​poor dynamic balance of the cross-flow fan.

[0026] S2. Distribute the unbalance of the multi-section cross-flow fan across the entire circumferential model, observe the distribution of the unbalance, and adjust the distribution angle until the unbalance of the multi-section cross-flow fan is relatively evenly distributed on the circumferential model. Obtain the new inter-section deflection angle value and derive the calculation formula [(n-1) / 2]*360° / n. Calculate the inter-section deflection angle corresponding to the number of sections of the multi-section cross-flow fan using this formula. This allows the radius line representing the unbalance projected onto the circumferential model to be distributed relatively evenly on the circumferential model. When fed back to the actual product, this can achieve mutual cancellation of the unbalance.

[0027] S3. Analyze the zonal balance of the multi-section cross-flow fan in the axial direction, establish a circular ring model, and use the radius and sphere to represent the unbalanced direction. Simulate the spatial arrangement of the multi-section assembly according to the inter-section deflection angle in step S2, observe the rotation dynamics of the sphere, and make the rotation of the sphere in the axial direction achieve a state of dynamic balance difference cancellation. The rotation of the sphere in this circular ring model reflects the dynamic balance of the cross-flow fan in the impeller axial direction composed of the middle section.

[0028] S4. Analyze the blade overlap of the middle section of the multi-section cross-flow fan. First, compare the blade deflection positions of two consecutive middle sections, and then compare the blade deflection positions of all middle sections. The final solution is a design model that avoids blade overlap and ensures that the blades are not completely evenly distributed on the 360° circumference. In addition to operating balance, noise issues must also be considered in the production of cross-flow fans. Therefore, blade overlap should be avoided in the overall structure. Simulate the blade overlap to observe whether there is a segmented overlapping phenomenon.

[0029] S5. Analyze the distribution of circumferential dynamic balance differences under the newly determined inter-section deflection angle to make the line distribution on the circular model relatively balanced, while the circumferential distribution of the unbalanced lines on the circular model is not completely uniform; the distribution of the unbalance of the cross-flow fan on the circumferential model is finitely non-uniform, so that the noise generation points of the single section in the middle section also show irregular distribution, which will not lead to the resonance superposition of sound waves and is conducive to the mutual cancellation and reduction of sound waves.

[0030] S6. After determining the final design model and obtaining the optimal inter-section deflection angle implementation scheme, the middle section of the multi-section cross-flow fan is welded.

[0031] In this invention, a multi-section cross-flow fan with 13 sections is used as the test object. The welding scheme with a small inter-section deflection angle in the prior art is used as a comparative example. The inter-section deflection angle is adjusted to 360° / n and [(n-1) / 2]*360° / n as Example 1 and Example 2. Specifically, the inter-section deflection angle of the comparative example is 5°, the inter-section deflection angle of Example 1 is 28°, and the inter-section deflection angle of Example 2 is 166°.

[0032] like Figure 1 In the comparative circular model shown, a small inter-node deflection angle of 5° is used to reflect the distribution of imbalance on the circular model. The imbalance of the cross-flow fan is concentrated in one-quarter of the circular model. The imbalance will form a superposition effect, and the corresponding cross-flow fan product will show a fixed problem of poor dynamic balance.

[0033] like Figure 2 In the circumferential models of Examples 1 and 2 shown, the inter-node deflection angles of 28° and 166° are used to reflect the distribution of unbalance on the circumferential model. The unbalance of the cross-flow fan is relatively evenly distributed on the circumference, and the unbalances will cancel each other out. Therefore, the overall dynamic balance level of the corresponding cross-flow fan product is good.

[0034] like Figure 3 In the circular ring model of Example 1 shown, a 28° inter-segment deflection angle is used to reflect the spherical three-dimensional rotation diagram on the circular ring model. The sphere rotates spirally upward in a single-cycle rotation manner. The rotation status in the axial direction of the circular ring model reflects that the dynamic balance of the first half is biased to one side, while the dynamic balance of the second half is biased to the other side. There is still a situation where the dynamic balance difference is locally superimposed.

[0035] like Figure 4 In the annular model of Example 2 shown, a 166° inter-segment deflection angle is used to reflect the spherical three-dimensional rotation diagram on the annular model. The sphere rotates spirally upward in a manner of 6 rotations. The rotation status in the axial direction of the annular model reflects the state of dynamic balance difference cancellation in the axial direction as well. Therefore, the dynamic balance effect of the corresponding irrigation fan product can be effectively improved.

[0036] Therefore, taking a cross-flow fan with 13 sections as an example, the scheme using a 166° inter-section deflection angle is better than the scheme using a 28° inter-section deflection angle; the following embodiments will further illustrate this with Embodiment 2 using a 166° inter-section deflection angle.

[0037] In the blade stacking simulation of Example 2, which uses an internode deflection angle of 166°, it was found that the blades overlapped. Therefore, the internode deflection angle was further adjusted, and within a tolerance range of ±10°, Example 3 was obtained with an internode deflection angle of 159°.

[0038] like Figure 5 and Figure 6 In the simulation diagram of the blade superposition state shown in Example 3, the blade deflection positions of two consecutive middle sections and all middle sections of the scheme with an internode deflection angle of 159° are simulated by overlapping. The resulting simulation pattern shows that the blades have misaligned spacing, no overlap, and no obvious regular local distribution changes.

[0039] Furthermore, a simulation analysis was performed on the imbalance in Example 3, such as... Figure 7 In the circular model of Example 3 shown, the distribution of the radius lines on the overall circumference is relatively balanced, and the center of gravity is basically at the center of the circle; and the distribution of the radius lines representing the unbalanced state on the circumference is not completely uniform, but has a certain degree of difference, which means that the noise generation points of the middle section are also irregularly distributed, and will not cause the resonance superposition of sound waves. On the basis of improving the dynamic balance effect, the noise generation can be reduced.

[0040] Finally, samples corresponding to the comparative examples and Examples 1 to 3 were prepared, and dynamic balancing tests were conducted on the samples for comparison. The samples of the comparative examples exhibited severe shaking during the dynamic balancing test, and the dynamic balance exceeded the measurement limit and could not be leveled; the samples of Example 1 showed slight shaking during the dynamic balancing test, but the dynamic balance could be leveled; the samples of Examples 2 and 3 did not shake during the dynamic balancing test, and the dynamic balance was easily leveled.

[0041] Combined with axial dynamic balance analysis, the optimal inter-section deflection angle for a multi-section cross-flow fan with 13 sections was determined to be 159°.

Claims

1. A method of producing a multi-sectioned cross-flow fan, comprising a step of welding a middle section of the multi-sectioned cross-flow fan, characterized by: In the welding process of the middle section of a multi-section cross-flow fan, the deflection angle between each middle section is set to [(n-1) / 2]*360° / n, with a tolerance range of ±10°, where n is the number of middle sections of the multi-section cross-flow fan. Includes the following steps: S1. Analyze the dynamic balance of the multi-section cross-flow fan, establish a mathematical model, use a circular model to represent the projection of the middle section of the multi-section cross-flow fan with the same structure, and use the radius line of the circle to represent the unbalance and direction of the multi-section cross-flow fan. S2. Distribute the unbalance of the multi-section cross-flow fan across the entire circumferential model, observe the distribution of the unbalance, and adjust the distribution angle until the unbalance of the multi-section cross-flow fan is relatively evenly distributed on the circumferential model. Obtain the new inter-section deflection angle value and derive the calculation formula [(n-1) / 2]*360° / n. S3. Analyze the partition balance of the multi-section cross-flow fan in the axial direction, establish a circular ring model, and use the radius and sphere to represent the unbalanced direction. Simulate the spatial arrangement of the multi-section assembly according to the inter-section deflection angle in step S2, observe the rotation dynamics of the sphere, and make the rotation of the sphere in the axial direction achieve a dynamic balance difference cancellation state. S4. Analyze the blade overlap of the middle section of the multi-section cross-flow fan. First, compare the blade deflection positions of two consecutive middle sections, and then compare the blade deflection positions of all middle sections. The final solution is a design model that avoids blade overlap and avoids the blades being arranged in a completely balanced manner on the 360° circumference. S5. Analyze the distribution of circumferential dynamic balance differences under the newly determined internode deflection angle to make the line distribution on the circular model relatively balanced, while the circumferential distribution of unbalanced lines on the circular model is not completely uniform. S6. Determine the final design model and weld the middle section of the multi-section cross-flow fan.

2. The method of producing a multi-section cross-flow fan according to claim 1, characterized by: The multi-section cross-flow fan has 13 middle sections, and the deflection angle between the middle sections is 159°.

Images