Fan wheel with at least one compensating element for correcting an imbalance

Abstract

having a fan wheel (1) an inner ring (5) rotatable about an axis of rotation (3), an outer ring (7) connected to the inner ring (5) and arranged radially outside the inner ring (5) with at least one compensating form element (11) integrally formed therewith, which projects at least sectionally beyond a base body (13) of the outer ring (7) and forms a material reserve for selective material removal to correct an imbalance of the fan wheel (1) and several fan blades (9) between the inner ring (5) and the outer ring (7).

Description

[0001] The invention relates to a fan wheel according to claim 1.

[0002] In injection-molded plastic fan impellers, particularly for axial and radial fans used in HVAC systems, automotive applications, and household appliances, deviations in mass distribution can occur during manufacturing. These deviations are due to uneven material distribution, geometric asymmetries, and shrinkage or warping during cooling. Sufficient static and dynamic balancing is crucial for the operation of rotating fan impellers. Imbalance can be corrected after demolding by manually or automatically applying balancing elements to specific areas of the impeller.

[0003] The object of the present invention is to make the fan wheel more cost-effective and simpler to construct. The fan wheel should be easier to balance.

[0004] At least one of these problems is solved by a fan wheel with all the features of claim 1. This allows the fan wheel to be manufactured more cost-effectively and simply. The manufacturing process can be faster. The number of fan wheel components can be reduced. Furthermore, the assembly time of the fan wheel can be shortened. The balancing process can be simplified. The balancing accuracy can be increased. The fan wheel can generate less vibration and noise during operation.

[0005] The fan wheel can be used in an axial fan and / or a radial fan. The fan wheel can be used in a vehicle.

[0006] The fan wheel can be made of plastic. The fan wheel can be manufactured using an injection molding process.

[0007] The inner ring, the outer ring, and / or the fan blades can be manufactured as a single piece. The inner ring can be connected to the outer ring via the fan blades.

[0008] The base body of the outer ring can be the actual body of the outer ring, independent of the at least one compensating element. The base body can be cylindrical and / or annular.

[0009] The at least one compensating element can be manufactured together with the fan wheel. The at least one compensating element can be molded in one piece with the outer ring during the injection molding process. The at least one compensating element can be arranged along the outer circumference of the outer ring. The at least one compensating element can project radially and / or axially from the base body.

[0010] The inclusion of at least one compensating element eliminates the need for subsequently attached external balancing clips. This at least one compensating element can be designed solely for the purpose of providing a material reserve.

[0011] The material reserve may be designed for material removal to correct imbalance. Particularly after injection molding, the material reserve can be removed by cutting, scraping, milling, and / or trimming. Material removal can be achieved through machining.

[0012] Material removal may be possible depending on imbalance measurements. The fan wheel can be tested on a balancing machine for this purpose. Material removal may be possible depending on static and / or dynamic imbalance.

[0013] Material removal through machining can be selectively limited to predetermined sections of the material reserve. This material removal can be performed without damaging the main body of the fan wheel.

[0014] In a specific embodiment, the outer ring can have several one-piece compensating elements distributed around the axis of rotation. The compensating elements can be spaced apart from each other circumferentially. The compensating elements can be segmented. The compensating elements can be arranged on the same diameter.

[0015] In a specific embodiment, the compensating elements can be evenly distributed around the axis of rotation. The compensating elements can be arranged at equal angular intervals around the axis of rotation. The compensating elements can be distributed symmetrically around the axis of rotation. The compensating elements can have an equal circumferential distance from each other. The compensating elements can be distributed rotationally symmetrically with respect to the axis of rotation. The compensating elements can be spaced circumferentially at an angle of 360° / number of compensating elements from each other.

[0016] In an advantageous embodiment, the balancing elements can be configured in terms of number, shape, and circumferential distribution to avoid introducing any additional imbalance to the fan wheel. Any additional imbalance could be an avoidable mass asymmetry caused by the balancing elements themselves on the outer ring. The balancing elements can be of identical construction. The balancing elements must not introduce any additional imbalance compared to the base body.

[0017] In a preferred embodiment, the number of compensating elements can be determined depending on the number of fan blades. The number of compensating elements can be less than, equal to, or greater than the number of fan blades.

[0018] In an advantageous embodiment, the number of compensating form elements can be greater than 2. The number of compensating form elements can be even or odd; the number can be 3, 5, or 7.

[0019] In a preferred embodiment, the at least one compensating element can project beyond the base body in a web-like manner. The at least one compensating element can be segmented. "Web-like" can mean that the at least one compensating element is only present on the base body in certain circumferential sections. "Web-like" can also mean that the at least one compensating element is designed as a segmental projection relative to the base body of the outer ring.

[0020] In a preferred embodiment, the at least one compensating element can be configured as a wall section extending in both the circumferential and axial directions. Alternatively, the at least one compensating element can be configured as a continuous wall section. The circumferential direction can be the direction around the axis of rotation. The axial direction can be a direction parallel to the axis of rotation.

[0021] The shape of the wall section can be determined using numerical flow calculations. The shape of the wall section can be designed to minimize its influence on the aerodynamic and / or acoustic performance of the fan impeller. This can improve the aerodynamic and / or acoustic performance of the fan impeller.

[0022] In a preferred embodiment, the outer ring can have an axial section, and the at least one compensating element can be configured as a wall section extending circumferentially along the axial section. An axial section can be a region of the outer ring extending parallel to the axis of rotation. The at least one compensating element can be configured as a circumferentially limited axial extension of the basic shape. The basic shape can be cylindrical or annular.

[0023] In a preferred embodiment, at least one of the compensating elements is suitable for deviating from another compensating element by means of selective material removal. The at least one compensating element can, for example, be axially and / or radially shorter than the other compensating element.

[0024] The following illustrations and figure descriptions depict special embodiments of the invention. Detailed character description Fig. 1: A side view of a fan wheel in a special embodiment of the invention. Fig. 2: A spatial view of the fan wheel from Fig. 1. Fig. 3: A section of a spatial view of the fan wheel from Fig. 1.

[0025] Fig. Figure 1 shows a side view of a fan wheel in a particular embodiment of the invention. The fan wheel 1 for an axial or radial fan comprises an inner ring 5 rotatable about an axis of rotation 3 and an outer ring 7 connected to the inner ring 5. The outer ring 7 is arranged radially outside the inner ring 5, and several fan blades 9 are distributed between the inner ring 5 and the outer ring 7. The fan blades 9, the inner ring 5, and the outer ring 7 are preferably formed integrally.

[0026] Fig. Figure 2 shows a spatial view of the fan wheel. Fig. 1. The outer ring 7 has several one-piece compensating elements 11 that project at least partially beyond a base body 13 of the outer ring 7 and form a material reserve for selective material removal to correct an imbalance of the fan wheel 1. The material reserve is specifically designed for machining to correct the imbalance. For example, the material reserve can be machined to remove material depending on the detection of the imbalance of the fan wheel 1.

[0027] The compensating elements 11, which are integrally formed with an axial section 23 of the outer ring 7 as a cylindrical base shape, are uniformly distributed around the axis of rotation 3. The number and circumferential distribution of the compensating elements 11 are specified such that no additional imbalance is introduced into the fan wheel 1 by the compensating elements 11. In particular, the number of compensating elements 11 is less than the number of fan blades 9. For example, a total of three compensating elements 11 and nine fan blades 9 are provided. The compensating elements 11 are spaced apart from each other at an equal circumferential distance, in particular at an angle 15 of 120°.

[0028] Fig. Figure 3 shows a section of a spatial view of the fan wheel. Fig.1. The at least one compensating element 11 projects beyond the base body 13 as a wall section 21 extending in the circumferential direction 17 and axial direction 19. The wall section 21 extends, in particular, the cylindrical axial section 23 of the outer ring 7. The circumferential length 25 of the compensating element 11 is, in particular, smaller than the circumferential connection width 27 of the fan blades 9 on the outer ring 7. The compensating element 11 is, in particular, located circumferentially between two adjacent fan blades 9. The compensating element 11 is spaced circumferentially from a connection area 29 of the fan blade 9 to the outer ring 7. Reference sign 1 fan wheel 3. Axis of rotation 5 inner ring 7 Outer ring 9 fan blades 11 Compensation form element 13 basic shapes 15 angles 17 Circumferential direction 19 Axial direction 21 wall section 23 Axial section 25 Circumference length 27 connection width 29 Connection area

Claims

fan wheel (1) comprising an inner ring (5) rotatable about an axis of rotation (3), an outer ring (7) connected to the inner ring (5) and arranged radially outside the inner ring (5) with at least one compensating element (11) formed integrally with it, which projects at least partially beyond a base body (13) of the outer ring (7) and forms a material reserve for selective material removal to correct an imbalance of the fan wheel (1), and several fan blades (9) between the inner ring (5) and the outer ring (7). Fan wheel (1) according to claim 1, characterized in that the outer ring (7) has several in-piece compensating elements (11) distributed around the axis of rotation (3). Fan wheel (1) according to claim 2, characterized in that the compensating elements (11) are evenly distributed around the axis of rotation (3). Fan wheel (1) according to claim 2 or 3, characterized in that the compensating elements (11) are designed in number, shape and circumferential distribution to avoid introducing any additional imbalance to the fan wheel (1) through the compensating elements (11). Fan wheel (1) according to one of claims 2 to 4, characterized in that a number of the compensating form elements (11) is determined depending on the number of fan blades (9). Fan wheel (1) according to claim 5, characterized in that a number of the compensating form elements (11) is greater than 2. Fan wheel (1) according to one of the preceding claims, characterized in that the at least one compensating form element (11) projects beyond the base body (13) in a web-like manner. Fan wheel (1) according to one of the preceding claims, characterized in that the at least one compensating form element (11) is designed as a wall section (21) extending in the circumferential direction (17) and axial direction (19) in a limited manner. Fan wheel (1) according to one of the preceding claims, characterized in that the outer ring (7) has an axial section (23) and the at least one compensating form element (11) is designed as a wall section (21) extending the axial section (23) circumferentially. Fan wheel (1) according to one of the preceding claims, characterized in that at least one of the compensating form elements (11) is suitable to deviate from another of the compensating form elements (11) by selective material removal.

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