Patent Application
20140298962
The subject invention relates to an elastic averaging alignment system and method for use with compliant materials and to the art of cutting punches and, more particularly, to cutting punches for use in forming elastic averaging features in compliant materials.
There exist numerous systems for aligning two or more components. In some cases, one component will include alignment pins, threaded rods, or other similar projecting structures. The projecting structures are configured to be received by oversized openings in a second component to facilitate a desired alignment. Generally, there exists a need to maintain tolerances between the projecting structure and corresponding openings sufficient to achieve the desired alignment of the components, including both two-way and four-way alignment. Using these alignment systems, misalignments may be magnified and tolerances may stack-up when the first member includes two or more spaced-apart projecting structures and alignment is required with a corresponding number of openings. While existing systems enable relative alignment of the components by allowing sufficient relative movement, the engagement of the alignment features (i.e., insertion of the protruding features in the holes) does not provide a predetermined alignment of the components, but only allows relative movement by an operator, tool, gauge or the like to obtain their desired alignment. Accordingly, it is desirable to provide an alignment system that incorporates alignment features that provide a desired alignment between the components.
In accordance with an exemplary embodiment, a cutting punch is disclosed. The cutting punch includes a central punching member, the central punching member comprising a cutting end, the cutting end having a peripheral shape. The cutting punch also includes at least one cutting element extending radially outwardly from the central punching member, the at least one cutting element having a cutting edge.
In accordance with another exemplary embodiment, a method of making a component alignment system is disclosed. The method includes providing a first component having a surface and a thickness. The method also includes forming a plurality of alignment features through the thickness of the first component, the alignment features comprising a plurality of elastically deformable apertures spaced-apart on the surface and extending through the thickness, each of the elastically deformable apertures comprising an aperture peripheral shape and having at least one slit extending radially-outwardly therefrom defining at least one elastically deformable wedge member.
In accordance with yet another exemplary embodiment, an elastic averaging alignment system is disclosed. The alignment system includes a first component comprising a surface, a thickness and a plurality of elastically deformable apertures spaced apart on the surface and extending through the thickness, each of the elastically deformable apertures comprising an aperture peripheral shape and having at least one slit extending radially-outwardly therefrom defining at least one elastically deformable wedge member.
The above features and advantages and other features and advantages of the invention are readily apparent from the following detailed description of the invention when taken in connection with the accompanying drawings.
Other features, advantages and details appear, by way of example only, in the following detailed description of embodiments, the detailed description referring to the drawings in which:
The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.
As used herein, the term “elastically deformable” refers to components, or portions of components, including component features, comprising materials having a generally elastic deformation characteristic, wherein the material is configured to undergo a resiliently reversible change in its shape, size, or both, in response to application of a force. The force causing the resiliently reversible or elastic deformation of the material may include a tensile, compressive, shear, bending or torsional force, or various combinations of these forces. The elastically deformable materials may exhibit linear elastic deformation, for example that described according to Hooke's law, or non-linear elastic deformation.
An alignment system that utilizes alignment features comprising elastically deformable apertures is disclosed. The elastically deformable apertures may be used with a rigid member, such as various rigid cylindrical pins, including hollow or solid pins, or spheres, to provide elastic averaging for precision location and alignment of all manner of mating components and component applications, including many industrial, consumer product (e.g., consumer electronics, various appliances, furniture and the like), transportation, energy and aerospace applications, and particularly including many types of vehicular components, including those utilizing compliant materials, such as all manner of liners, including headliners, trunk liners, door liners, dash liners, instrument panel liners, flooring, upholstery, including seating and other upholstered components, seals, including various door, trunk, sun roof, moon roof, dash and other elastomeric seals, sound damping materials and the like. The compliant materials may have any suitable forms, including various two-dimensional forms, such as sheets and pads, as well as various three-dimensional forms, such as molded parts having all manner of shapes that may be configured, whether by the use of various flanges or other positioning and alignment features, to utilize the positioning and alignment system described herein.
This invention uses a punch configured for use in compliant materials that furnishes an aperture and one or more wedges in the compliant material that will elastically adjust (i.e. elastically deform) when a pin, sphere, or other rigid mating feature is inserted into the aperture. The punch provides cuts or slits that radiate from an aperture in the form of a hole or slot and that comprise elastically deformable wedges which furnish elastic averaging capabilities within a compliant material. Incorporation of at least one aperture with the radiating slits, and preferably a plurality of apertures with the radiating slits, allows precision alignment between two mating components without additional tooling (i.e., using a single punch design). The aperture and the elastically deformable wedges are configured to interfere with a feature or features of the mating part or member that is substantially rigid (i.e., not elastically deformable) relative to the aperture and wedges. The over-constrained interfaces (i.e. due to the interference) will average each individual positional error of each elastically averaged aperture. These elastically averaged alignment features allow elastic averaging within a component formed from a compliant material and may provide for better coverage and fit of many compliant components, for example, increased perimeter coverage for various acoustic materials and seals, or reduced seal sizes due to improved precision of the seal location (i.e. not having to oversize a seal due to potential positional variation associated with its placement).
As the components are assembled the elastically deformable wedges that define the apertures are elastically deformed. The deformable wedges comprise cantilevered beam portions of the respective component. These cantilevered beams are elastically deformed, either by radial compression of the ends of the beams against the peripheries of the rigid members upon their insertion into the apertures, or a mode of radial, axial and/or circumferential bending of the deformable wedges as they are pressed against the rigid members, or a combination thereof, that creates interference conditions that elastically average the positional variations associated with the aperture/pin alignment features and provide a four-way locating scheme, since the rigid members may press against the apertures radially outward in any radial direction (i.e. 360°). Furthermore, the over-constrained interfaces of the rigid members will elastically deform each of the cantilevered beam wedges on each side of the mating apertures to an extent or degree that averages the individual positional error of each aperture. Elastic averaging provides elastic deformation of the interface(s) between mated components, wherein the average deformation provides a precise alignment, the manufacturing positional variance being minimized to Xmin, defined by Xmin=X√N, wherein X is the manufacturing positional variance of the locating features of the mated components and N is the number of features inserted. To obtain elastic averaging, an elastically deformable component is configured to have at least one feature and its contact surface(s) that is over-constrained and provides an interference fit with a mating feature of another component and its contact surface(s). The over-constrained condition and interference fit resiliently reversibly (elastically) deforms at least one of the at least one feature or the mating feature, or both features. The resiliently reversible nature of these features of the components allows repeatable insertion and withdrawal of the components that facilitates their assembly and disassembly. Positional variance of the components may result in varying forces being applied over regions of the contact surfaces that are over-constrained and engaged during insertion of the component in an interference condition. It is to be appreciated that a single inserted component may be elastically averaged with respect to a length of the perimeter of the component. The principles of elastic averaging are described in detail in detail in commonly owned, co-pending U.S. patent application Ser. No. 13/187,675, the disclosure of which is incorporated by reference herein in its entirety. The embodiments disclosed herein provide the ability to convert an existing component that is not compatible with the elastic averaging principles described herein to an assembly that does facilitate elastic averaging and the benefits associated therewith.
Referring generally to
In accordance with an exemplary embodiment of the invention, the plurality of cutting elements 6 include a first cutting member 16, a second cutting member 17, a third cutting member 18, a fourth cutting member 19, a fifth cutting member 20, a sixth cutting member 21, a seventh cutting member 22, an eighth cutting member 23, a ninth cutting member 24, and a tenth cutting member 25. Cutting elements 16-25 extend radially outwardly from central punching member 4 and have substantially planar surfaces, such as, for example, substantially planar surfaces 16′ and 16″ (
Referring to
The material 27 used to form the first component 102 may be any suitable compliant material. Depending on the thickness of the material 27 and the size and shape of the wedges, suitable materials may include various metals, thermoplastic polymers, thermoset polymers, woven and non-woven fabrics, or composites, or combinations thereof. Metals may include various metal sheets, including steel alloy and aluminum alloy sheets. Thermoplastic polymers and thermoset polymers may include various elastomers thereof, including natural and synthetic rubbers and silicones. Composites may include various polymer/fiber or fabric composites, or polymers that include other fillers, such as various particulate fillers, or combinations thereof.
Referring to
Referring to
An elastic averaging cutting punch in accordance with the exemplary embodiments may be used to form elastic averaging apertures 49 that establish a predetermined alignment of one member relative to another. In other words, the alignment system 100 described herein provides an alignment of the first component 102 and second component 120 to a predetermined position relative to one another where they may be fastened or fixed to one another by any suitable attachment device (not shown), such as all manner of mechanical fasteners, such as screws and the like, or attachment mechanism (not shown), including various adhesive members (e.g. adhesive tapes) or adhesive materials that may be applied to the first component 102 or second component 120.
While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the application.
