BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive.
FIG. 1 is an exploded perspective view of a buildup of two structures and an exemplary bushing assembly;
FIG. 2A is a perspective view of an exemplary compensator bushing;
FIGS. 2B-2F are plan views of the bushing of FIG. 2A;
FIG. 3A is a perspective view of an exemplary lock bushing;
FIGS. 3B-3F are plan views of the bushing of FIG. 3A;
FIG. 4A is a partial cutaway perspective view of the compensator bushing of FIG. 2A and the lock bushing of FIG. 3A engaged with each other;
FIG. 4B is a perspective view of the compensator bushing of FIG. 2A and the lock bushing of FIG. 3A engaged with each other;
FIGS. 4C-4H are top plan views illustrating exemplary engagement of an exemplary compensator bushing and an exemplary lock bushing;
FIGS. 5A-5C are top plan views illustrating placement of an exemplary compensator bushing in a counter-bored hole;
FIG. 6 is a perspective view of two structures attached to each other using an exemplary bushing assembly;
FIG. 7 is a partial cutaway perspective view of another exemplary bushing assembly held together with a retainer clip;
FIG. 8A is a perspective view of the exemplary compensator bushing of FIG. 7;
FIGS. 8B-8F are plan views of the bushing of FIG. 8A;
FIG. 9A is a perspective view of the exemplary lock bushing of FIG. 7; and
FIGS. 9B-9F are plan views of the bushing of FIG. 9A.
DETAILED DESCRIPTION
Given by way of overview and referring to FIG. 1, an exemplary bushing assembly 10 may be used in attaching two structures 12 and 14 to each other. Given by way of non-limiting example, the structures 12 and 14 are disposed against each other such that a fastener 16 that extends from the structure 14 is received in a counter-bored hole 18 defined in the structure 12. An actual location of the fastener 16 may have a variability v from a documented location (not shown for clarity) of the fastener 16, and the hole 18 is defined to receive the fastener 16 in the documented location of the fastener 16. A compensator bushing 20 is placed in the hole 18, and the compensator bushing 20 defines an opening 22 therethrough that has a dimension l1 along an axis a1, that is sized to receive the fastener 16 therethrough and that has a dimension l2 along an axis a2 that is larger than the dimension l1. The compensator bushing 22 is rotated until the compensator bushing 20 is received in the counter-bored hole 18. A lock bushing 24 is placed onto the compensator bushing 20, and the lock bushing 24 defines an opening 26 therethrough that is sized to receive the fastener 16 therein. The bushings 20 and 24 engage with each other, and the structure 12 and the bushings 20 and 24 are secured onto the fastener 16, thereby securing the structure 12 to the structure 14. Details will now be set forth below.
Referring additionally to FIGS. 2A-2F, the compensator bushing 20 defines surfaces 28 and 30 and a side 32. The compensator bushing 20 has an outer diameter that is equalized with a diameter of the counter-bore of the counter-bored hole 18. The opening 22 extends completely through the compensator bushing 20 from the surface 28 to the surface 30. In an exemplary embodiment, the opening 22 is a slot. The compensator bushing 20 may have any shape as desired for a particular application. While the compensator bushing 20 is shown herein as having a circular (that is, round) shape, the compensator bushing 20 may have any shape, such as without limitation oval, or square, or rectangular, or the like, as desired for a particular application.
The dimension l1 is sized to receive therein the fastener 16. The dimension l2 is bigger than the dimension l1 and is sized to accommodate the variability v of actual location of the fastener 16 from documented location of the fastener 16. Because the compensator bushing 20 can be rotated 360 degrees in the counter-bored hole 18, the opening 22 can accommodate the variability v that is up to two times the dimension l2. That is, the dimension l2 can be as little as one-half the length of the variability v. Thus, the dimension l2 is at least one-half the length of the variability v. The full variability v can be accommodated by rotating the compensator bushing 20 in the counter-bored hole 18 until the opening 22 is aligned to receive the fastener 16 therein. Given by way of non-limiting example, when the variability v is around ½ inch, the dimension l2 can be at least ¼ inch.
The compensator bushing 20 may have any thickness t1, as desired for a particular application. As a result, the thickness t1 may be sufficiently thin that the compensator bushing 20 may be considered and referred to as washer. Thus, the term “bushing” as used herein is intended to include “washer” within its meaning. Further, the compensator bushing 20 may be made from any material whatsoever, such as without limitation plastic or metals such as stainless steel or titanium, as desired for a particular application. Factors that may be taken into consideration for selection of materials may include: whether the compensator bushing 20 will be used to transfer load; electro-corrosive compatibility with materials used for the fastener 16 and the structures 12 and 14 (such as avoiding use of dissimilar metals); environmental factors; or the like.
Referring additionally to FIGS. 3A-3F, the lock bushing 24 defines surfaces 34 and 36 and a side 38. The lock bushing 24 has an outer diameter that is smaller than a diameter of the counter-bore of the counter-bored hole 18. The opening 26 extends completely through the lock bushing 24 from the surface 34 to the surface 36. The opening 26 has a diameter that is sized to receive the fastener 16 therein. The lock bushing 24 may have any shape as desired for a particular application. While the lock bushing 24 is shown herein as having a circular (that is, round) shape, the lock bushing 24 may have any shape, such as without limitation oval, or square, or rectangular, or the like, as desired for a particular application.
The lock bushing 24 may have any thickness t2 as desired for a particular application. As a result, the thickness t2 may be sufficiently thin that the lock bushing 24 may be considered and referred to as washer. Thus, the term “bushing” as used herein is intended to include “washer” within its meaning. Like the compensator bushing 20, the lock bushing 24 may be made from any material whatsoever, such as without limitation plastic or metals such as stainless steel or titanium, as desired for a particular application. Factors that may be taken into consideration for selection of materials for the lock bushing 24 are the same as those set forth above for the compensator bushing 20.
The compensator bushing 20 and the lock bushing 24 each include features that cooperate together to provide means for engaging the compensator bushing 20 and the lock bushing 24. In an exemplary embodiment, serrations 40 are defined on the surface 28 of the compensator bushing 20 and serrations 42 are defined on the surface 34 of the lock bushing 24. The serrations 40 are parallel and the serrations 42 are parallel. In an exemplary embodiment, the serrations 40 and 42 extend across the entire surfaces 28 and 34, respectively.
The serrations 40 and 42 are made as small as desired for a particular application. Use of small serrations allows for finer control of variability of tolerances and a tighter tolerance with the shaft of the fastener 16. In an exemplary, non-limiting embodiment, the serrations 40 and 42 are made according to industry machining standards.
As best seen in FIGS. 2A and 2B, in an exemplary embodiment the serrations 40 are aligned on the surface 28 of the compensator bushing 20 such that their axes form a non-zero angle with the axis a2 (that is, the serrations 40 are not parallel with the axis a2). The non-zero angle suitably is no more than ninety degrees. The amount of load that can be transferred is maximized when the non-zero angle is ninety degrees. The amount of load that can be transferred is reduced as the non-zero angle approaches zero. This reduction results because, after the lock bushing 24 is placed onto the compensator bushing 20, the lock bushing 24 could slide on the serrations 40 and 42 along the axis a2.
Referring additionally to FIGS. 4A and 4B, after the compensator bushing 20 is placed into the counter-bored hole 18 (not shown in FIGS. 4A and 4B), the surface 34 of the lock bushing 24 is placed against the surface 28 of the compensator bushing 20 such that “teeth” of the serrations 40 and 42 are received within (that is, engaged with) “valleys” of the serrations 42 and 40, respectively.
The means for engaging may be implemented in several ways in other exemplary embodiments, as desired. For example, referring now to FIG. 4C, in another exemplary embodiment the surface 34 of a lock bushing 24C and the surface 28 of a compensator bushing 20C may be treated with a surface treatment 54 to provide a non-skid type surface with an increased coefficient of static friction. The surface treatment 54 may be effected by any suitable, abrasive mechanical processing or by a suitable chemical processing, such as an acid bath or the like. After the compensator bushing 20C is placed into the counter-bored hole 18 (not shown in FIG. 4C), the surface 34 of the lock bushing 24C is placed against the surface 28 of the compensator bushing 20C such that the increased coefficient of static friction of the surface treatment 54 engages the lock bushing 24C and the compensator bushing 20C. This engagement is similar to a knurled or cross-hatched washer that is used to prevent a nut from loosening after installation.
Referring now to FIGS. 4D, 4E, and 4F, in another exemplary embodiment an adhesive 56 may be affixed only to the surface 34 of a lock bushing 24D (FIG. 4D) or only to the surface 28 of a compensator bushing 20D (FIG. 4E) or to the surface 34 of the lock bushing 24D and to the surface 28 of the compensator bushing 20D (FIG. 4F), as desired. After the compensator bushing 20D is placed into the counter-bored hole 18 (not shown in FIGS. 4D, 4E, and 4F), the surface 34 of the lock bushing 24D is placed against the surface 28 of the compensator bushing 20D. The adhesive 56 is allowed to cure, thereby engaging the lock bushing 24D and the compensator bushing 20D.
Referring now to FIGS. 4G and 4H, in another exemplary embodiment hook and loop fasteners may be used to engage a lock bushing 24E and a compensator bushing 20E in applications subject to light loading. Hooks 58 may be affixed to the surface 34 of the lock bushing 24E and loops 60 may be affixed to the surface 28 of the compensator bushing 20E (FIG. 4G). Alternately, the loops 60 may be affixed to the surface 34 of the lock bushing 24E and the hooks 58 may be affixed to the surface 28 of the compensator bushing 20E (FIG. 4H). After the compensator bushing 20E is placed into the counter-bored hole 18 (not shown in FIGS. 4G and 4H), the surface 34 of the lock bushing 24E is placed against the surface 28 of the compensator bushing 20E. The hooks 58 engage the loops 60, thereby engaging the lock bushing 24E and the compensator bushing 20E.
Referring now to FIGS. 5A, 5B, and 5C, the structure 12 is placed onto the fastener 16 that may or may not be mislocated. The compensator bushing 20 is rotated as desired (if at all) to compensate for any mislocation of the fastener. In. FIG. 5A, the fastener 16 is centered. The compensator bushing 20 is placed onto the fastener 16 and fits into the counter-bored hole 18 without being rotated. The lock bushing 24 is placed onto and engages the compensator bushing 24.
In FIG. 5B, the fastener 16 is mislocated by an intermediate amount of variability. The compensator bushing 20 is placed onto the fastener 16 and is rotated until the compensator bushing 20 fits into the counter-bored hole 18. The lock bushing 24 is placed onto and engages the compensator bushing 24.
In FIG. 5C, the fastener 16 is mislocated by an amount of variability that is greater than that shown in FIG. 5B. The compensator bushing 20 is placed onto the fastener 16 and is rotated (more than the amount of rotation shown in FIG. 5B) until the compensator bushing 20 fits into the counter-bored hole 18. The lock bushing 24 is placed onto and engages the compensator bushing 24.
Referring now to FIGS. 1 AND 6, after the compensator bushing 20 is placed about the fastener 16 in the counter-bored hole 18 and the lock bushing 24 engages the compensator bushing 20, a washer 62 is placed onto the lock bushing 24. A nut 64 is placed onto threads of the fastener 16 and is tightened, thereby securing the structure 12 (and the compensator bushing 20 and the lock bushing 24) onto the fastener 16.
Referring now to FIGS. 7, 8A, and 9A, in some applications such as modifications or alterations or retrofits or repairs made in the field, it may be desirable to provide a bushing assembly as a one-piece unit. To that end, and given by way overview of another non-limiting example, in an exemplary bushing assembly 110 a compensator bushing 120 defines a slot 122 therethrough that has the dimension l1 along the axis a1, that is sized to receive the fastener 16 (not shown) therethrough. The compensator bushing 120 has a dimension l2 along an axis a2 that is larger than the dimension l1. The compensator bushing 120 defines a slot 123 therethrough that has a dimension l3 along the axis a1, that is bigger than the dimension l1 and that has a dimension l4 along the axis a2 that is larger than the dimension l2. A lock bushing 124 defines an opening 126 therethrough that is sized to receive the fastener 16 (not shown) therein. Means are provided for engaging the bushings 120 and 124. Details will now be set forth below.
Referring additionally to FIGS. 8B-8F, the compensator bushing 120 is similar to the compensator bushing 20 (FIGS. 2A-2F) except that the compensator bushing 120 additionally defines the slot 123. The slot 123 accommodates a retainer clip 102 and washer 104. Moreover, a side 132 of the compensator bushing 120 optionally may be chamfered over a thickness t3, if desired, for radius relief. If provided, the chamfer may have any degree measurement as desired. The compensator bushing 120 includes the features that contribute to the means for engaging the lock bushing that are described above for the compensator bushing 20.
Referring now to FIGS. 9A-9F, the lock bushing 124 is similar to the lock bushing 24 (FIGS. 3A-3F) except an opening 126 optionally may be chamfered toward a surface 136, if desired. If provided, the chamfer may have any degree measurement as desired. The chamfer may accommodate receiving a one-piece nut 106 (FIG. 7) thereagainst without a washer.
Because the bushing assembly 110 is a one-piece assembly, the compensator bushing 120 is rotated until it fits into the counter-bored hole 18 (not shown) and the nut 106 is rotated to secure the structure 12 (not shown) onto the fastener 16 (not shown).
While a number of exemplary embodiments and aspects have been illustrated and discussed above, those of skill in the art will recognize certain modifications, permutations, additions, and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions, and sub-combinations as are within their true spirit and scope.
Patent Application
20080003079
