Patent Application
20200080567
The present disclosure relates to an alternator cooling fan including fan blades with an adjustable pitch.
This section provides background information related to the present disclosure, which is not necessarily prior art.
Alternators are widely used electrical generators for converting mechanical energy to electrical energy in the form of alternating current. While current alternators are suitable for their intended use, they are subject to improvement. For example, alternators often include a cooling fan, which may generate excessive noise during operation. An alternator that generates less noise than existing alternators would therefore be desirable. The present disclosure advantageously provides for such an alternator.
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
The present disclosure includes a cooling fan for an alternator. The cooling fan has a fan body and a plurality of fan blades extending from the fan body. A hinge is located where each one of the fan blades meets the fan body. The hinge allows the plurality of fan blades to pivot relative to the fan body. The degree of pivot is proportional to rotational speed of the fan body.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustrative purposes only of select embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
Example embodiments will now be described more fully with reference to the accompanying drawings.
The alternator 10 generally includes a stator 12 and a rotor 14. The stator 12 is a stationary set of conductors wound in coils on a core, such as an iron core. The rotor 14 is a rotating magnet that turns within the stator 12. An electrical current is induced in the stator 12 by the rotating magnetic field of the rotor 14. The magnetic field of the rotor 14 may be produced by permanent magnets, or by a field coil electromagnet. With respect to automotive applications, a rotor winding may be used, which allows control of the voltage generated by the alternator 10 by varying the current in the rotor field winding.
The alternator 10 further includes a cooling fan 20 for cooling components of the alternator 10 during operation. The cooling fan 20 may be attached directly to the rotor 14 such that the cooling fan 20 rotates with the rotor 14. With continued reference to
The cooling fan 20 includes a plurality of fan blades 30, which extend from the fan body 22. The fan blades 30 mate with the fan body 22 at hinges 32. The fan blades 30 may be made of the same material as the rest of the fan body 22, or may be made of any other suitable material. For example, the fan blades 30 may be made of any suitable metallic material or any suitable polymeric material. The hinges 32 advantageously allow the fan blades 30 to pivot relative to the fan body 22. The degree of pivot is proportional to the rotational speed of the fan body 22 as the fan body 22 rotates in rotational direction R, which as illustrated in the example of
The cooling fan 20 further includes a plurality of pitch control members 40, which regulate the degree of pivot of the fan blades 30. The pitch control members 40 extend from the fan body 22 to different ones of the fan blades 30. Specifically and with reference to
The pitch control members 40 may exert force upon the fan blades 30 in a direction away from the fan body 22. The pitch control members 40 may be springs and/or made of any suitable elastic material, such as any suitable elastomeric polymer, effective to support the fan blades 30 generally upright when the fan body 22 is not rotating, as illustrated in
The pitch control members 40 may include a temperature sensitive material having a rigidity that varies in response to temperature changes. Any suitable temperature sensitive material may be used, such as any suitable temperature sensitive polymer. The temperature sensitive material becomes relatively less rigid and more flexible at relatively cooler temperatures, and becomes relatively more rigid and less flexible at relatively warmer temperatures. Thus at relatively warmer temperatures at which additional cooling is required, the pitch control member 40 will support the fan blades 30 relatively more upright such that the fan blades 30 are more effective to generate airflow for cooling. At relatively cooler temperatures at which less cooling airflow is needed, the temperature sensitive material of the pitch control member 40 will be less rigid and more flexible to allow the fan blades 30 to rotate/bend further about the hinges 32 towards the fan body 22, thereby resulting in the fan blades 30 generating less airflow for cooling.
The present disclosure thus provides numerous advantages over the art. The fan blades 30 are mounted such that at hinges 32 the fan blades 30 pivot to allow the pitch of the fan blades 30 to vary based on the rotational speed of the cooling fan 20. The pitch control members 40 provide a force pushing on the fan blades 30 and controlling the pitch thereof. As the rotor 14 and the fan body 22 attached thereto rotate faster, force exerted on the fan blades 30 causes the pitch control members 40 to compress (see
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
