The present disclosure generally relates to systems and methods for applying a tunable elastic force, and more particularly relates to the use of metallic glass elastic elements to apply force in a mechanical system.
Spring-like elements are available in a wide variety of forms. For example, coil, torsion, disc, leaf and clip springs, as well as resilient material components serve as elastic elements for uses such as force application, clamping and vibration damping. These elements may experience fatigue degradation under load or after repeated cycling, may have limited stiffness ranges, and may be difficult to form for restricted packaging spaces.
Accordingly, it is desirable to provide systems and methods that provide elastic elements with greater design flexibility. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and introduction.
Systems and methods are provided with elastic elements that have configurable force versus displacement characteristics for a variety of applications. In various embodiments, an elastic element is configured to deflect from a base shape when a load is applied and to resume the base shape when the load is removed. The elastic element formed of a metallic glass material. The elastic element applies a force to a moveable element.
In other embodiments, the elastic element has a cross sectional profile that is configured to vary the force as the elastic element deflects.
In other embodiments, the elastic element has a shape that is irregular and that is determined by a space within which the elastic element is disposed.
In other embodiments, the elastic element is shaped as a disc with a center opening and with a periphery opposite the center opening at an outermost edge of the elastic element. The elastic element has a cross sectional profile with one thickness at the center opening and a different thickness at the periphery
In other embodiments, the elastic element has a cross sectional profile with a thickness that varies and that may include ribs and grooves configured to vary the force as the elastic element deflects.
In other embodiments, the elastic element is disposed within a continuously variable transmission. A sheave in the continuously variable transmission is variable in diameter, and the elastic element applies the force to the sheave.
In other embodiments, a piston with a rod engages the sheave, and the elastic element is disposed around the rod. The elastic element may be disc shaped with a center opening through which the rod extends.
In other embodiments, the elastic element has a conical shape.
In another embodiment, a method includes forming an elastic element in a base shape which deflects when a load is applied and which resumes the base shape when the load is removed. The elastic element is formed of a metallic glass material. A moveable element is positioned so that the elastic element applies a force to the moveable element.
In other embodiments, the method includes forming the elastic element with a cross sectional profile that is configured to vary the force as the elastic element deflects.
In other embodiments, the method includes forming the elastic element with a shape that is irregular and that is determined by a space within which the elastic element is disposed.
In other embodiments, the method includes shaping the elastic element as a disc with a center opening and a periphery opposite the center opening at an outermost edge of the elastic element. A cross sectional profile of the elastic element is cast with one thickness at the center opening and another second thickness at the periphery.
In other embodiments, the method includes casting the elastic element with a cross sectional profile that has a thickness that varies.
In other embodiments, the method includes casting ribs and grooves on the elastic element, configured to vary the force as the elastic element deflects.
In other embodiments, the method includes positioning the elastic element in a continuously variable transmission. The elastic element applies the force to a sheave in the continuously variable transmission that has a variable in diameter.
In other embodiments, the method includes engaging the sheave with a piston rod, and the elastic element is positioned around the rod.
In other embodiments, the method includes shaping the elastic element as a disc with an opening at its center, and extending the rod through the opening
In additional embodiments, an elastic element is formed in a disc shape and is configured to deflect from a base shape when a load is applied and to resume the base shape when the load is removed. The elastic element is cast of a metallic glass material. A rib is cast onto the elastic element and is configured to vary force as the elastic element deflects. The elastic element applies the force to a moveable element.
The exemplary embodiments will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:
The following detailed description is merely exemplary in nature and is not intended to limit the application or its uses. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, introduction, brief summary or the following detailed description.
In one or more example implementations of the disclosed elastic element system and method, tunable stiffness is provided. Generally, the stiffness may be tailored through variations in cross sectional thickness enabled by using metallic glass to form the elastic element. High fatigue life is achievable with lifetime consistent performance as a result of near zero stress relaxation of the metallic glass material. In certain embodiments, irregular shapes of the elastic element may readily be formed such as by casting, to fit the packaging space dictated by the application.
The current description relates to elastic element systems that may be described in the context of a mechanical system application and in particular, a continuously variable transmission (CVT) system, for purposes of demonstrating an example. During operation, it may be useful to control the movement of the CVT's sheaves under controlled force and/or at variable forces. For example, to effectively vary the diameter of a sheave, one force may be preferred at a specific operating point of the CVT and another force may be preferred at a different operating point of the CVT.
The present disclosure is not limited to CVT applications or to transmissions in general, but rather, also encompasses any application where a consistently repeatable application of a force profile by an elastic element is desired. Accordingly, the teachings of the present disclosure are applicable to mechanical systems in a variety of applications, such as vehicle systems, machinery and equipment systems, and others.
In an exemplary embodiment of the present disclosure as further described below, an elastic element is configured to deflect from a base shape when a load is applied and to resume the base shape when the load is removed. The elastic element is formed of a metallic glass material. The elastic element applies a force to a moveable element to effect a desired action. Accordingly, with reference to
In the embodiment of
With reference to
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In a number of embodiments such as shown in
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Accordingly, an elastic element system and a method provide tunable stiffness that may be tailored through variations in cross sectional thickness enabled by using metallic glass to form the elastic element. High fatigue life is achievable with lifetime consistent performance as a result of near zero stress relaxation of the metallic glass material. While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the disclosure in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing the exemplary embodiment or exemplary embodiments. It should be understood that various changes can be made in the function and arrangement of elements without departing from the scope of the disclosure as set forth in the appended claims and the legal equivalents thereof.