BRIEF DESCRIPTION OF THE DRAWINGS
The exact nature of this invention, as well as the objects and advantages thereof, will become readily apparent from consideration of the following specification in conjunction with the accompanying drawings in which like reference numerals designate like parts throughout the Figures thereof and wherein:
FIG. 1 is a perspective view of a prior art tolerance ring design.
FIG. 2 is a perspective view of a tolerance ring with according to one embodiment of the present invention.
FIG. 3 is a perspective view of a tolerance ring according to another embodiment of the present invention.
FIG. 4 is a cross-sectional view of the tolerance ring along line 4 of FIGS. 2 or 3.
FIG. 5 is a perspective view of a tolerance ring according to yet another embodiment of the present invention.
FIG. 6 illustrates a cross-sectional view of the tolerance ring along line 6-6 of FIG. 5.
FIG. 7 illustrates another cross-sectional view of the tolerance ring along line 6-6 of FIG. 5.
FIG. 8 is a perspective view of a tolerance ring according to a further another embodiment of the present invention.
FIG. 9 illustrates a cross-sectional view of the tolerance ring along line 9-9 of FIG. 8.
FIG. 10 illustrates another cross-sectional view of the tolerance ring along line 9-9 of FIG. 8.
FIG. 11 is a perspective view of a tolerance ring according to another embodiment of the present invention.
FIG. 12 is a perspective view of a tolerance ring according to yet another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a perspective view of a prior art tolerance ring design 11. In one embodiment, the tolerance ring 11 is made from 300 Series stainless steel. The tolerance ring 11 is formed from a substantially planar base portion that is curved to form a cylinder 13. The cylinder 13 has a first radius about a central axis and extends for a fixed length parallel to the central axis. Radial expansion and contraction of cylindrical opening 19 is facilitated by a gap 21 along the length of tolerance ring 11, the gap 21 having a first edge 15 and a second edge 17. 100301 The tolerance ring 11 has a plurality of contacting portions 23. The contacting portions 23 generally have a rhomboidal cross-sectional shape extending axially along the cylinder 13. As shown in FIG. 1, the contacting portions 23 project radially outward in a direction away from the interior of the tolerance ring 11. It is recognized that alternative configurations known in the art include tolerance rings with contacting portions 23 that project radially inward or project inward and outward in an alternating fashion.
FIG. 2 is a perspective view of a tolerance ring 25 with hook-shaped tabs and a cut-out feature for mass control according to one embodiment of the present invention. The tolerance ring 25 has hook-shaped tabs 27 and 29 with opposite mating ends. These ends engage one another to close the linear gap 21 (FIG. 1) formed between the tabs 27 and 29. Edges 15 and 17 have cut-outs 31 and 33, respectively, to balance the increase in mass from the hook-shaped tabs 27 and 29. When the hook-shaped tabs 27 and 29 engage one another, cut-outs 31 and 33 are proximately aligned with one another to form a cavity 35 in the tolerance ring 25. The hook-shaped tabs and cut-out features of the tolerance ring 25 improve mass eccentricity and reduce mass imbalance of the actuator arm assembly.
FIG. 3 is a perspective view of a tolerance ring 37 with three hook-shaped tabs and cut-out feature. The tolerance ring 37 has hook-shaped tabs, generally indicated 39, 41 and 43, with opposite mating ends on the first and second edges 15 and 17, respectively. To balance an increase in mass on one end of the tolerance ring 37 resulting from the hook-shaped tabs 39, 41 and 43, cut-outs are made in edges 15 and 17, generally shown as cavities 47 and 45. The hook-shaped tabs and cut-outs of the tolerance ring 37 improve mass eccentricity and reduce mass imbalance of the actuator arm assembly.
FIG. 4 is a cross-sectional view of the tolerance ring along line 4-4 of FIGS. 2 or 3, illustrating a cut-out feature in accordance to one embodiment of the present invention. The hook-shaped tabs 27 and 29 engage one another to close the gap 21 (FIG. 1) formed between the first tab 15 and the second tab 17. Typically, the gap 21 allows tolerance rings to readily interlock during shipping and handling. Separating interlocked tolerance rings is time consuming, expensive and may subject the tolerance rings to handling damage. Hence, by eliminating this gap 21, the tolerance ring 25 or 37 has an additional advantage of not tangling or interlocking with other tolerance rings 25 or 37 during shipping and handling.
FIG. 5 is a perspective view of a tolerance ring 47 according to another embodiment of the present invention. The aperture 51 is a cavity formed in the cylinder 13 that is at least large enough to receive the tab 49 on the opposite end. This tab 49 and aperture 51 feature of the tolerance ring 47 improves mass eccentricity and reduces mass imbalance of the actuator arm assembly. Tab 49 has a cavity or opening 53 to account for mass increase on one side of the tolerance ring 47 by the additional material of the tab 49. It can be envisioned that the tab 49 can have any configuration that is receivable by a mating aperture 520 on the opposite end.
FIG. 5 also illustrates an alternate configuration for contacting portions 23. Contacting portions 23 are arranged in a plurality of rows along the surface of the planar base portion 13.
FIGS. 6 and 7 illustrate alternate cross-sectional views of the tolerance ring 47 along line 6-6 of FIG. 5. The tab 49 is removably engageable with the aperture 51. FIG. 6 shows a tab 49 configuration that is tangential to the cylinder 13. FIG. 7 illustrates an alternate tab 49 configuration with a flange 55 to securely couple edges 15 and 17. By eliminating the gap 21, tolerance ring 47 has an additional advantage of not tangling or interlocking with other tolerance rings 47 during shipping and handling.
It is recognized that alternative tab and aperture configurations can be used while improving mass eccentricity and reducing mass imbalance of the actuator arm assembly. For example, the tolerance ring 47 can have a plurality of tabs that mate with a plurality of apertures.
FIG. 8 shows a perspective view of a tolerance ring 57 with two tabs 59 that are removably engageable with two apertures 61. The tabs 59 mate with apertures 61 in the same manner as explained in FIGS. 6 and 7. The tabs 59 clip or hook onto the edge of apertures 61, as shown in FIGS. 9 and 10. The tabs 59 can have an L-shaped or U-shaped flange 63 that hook on the edge of apertures 61 in the surface of the cylinder 13. By eliminating the gap 21, the mass eccentricity of the ring is improved with the additional advantage of producing a ring that does not tangle or interlock with other tolerance rings 47 during shipping and handling.
FIG. 11 is a perspective view of a tolerance ring 65 with cut-out feature for mass eccentricity control of the base portion. The tolerance ring 65 can have one or more cut-outs or apertures, generally shown as 67, along the cylinder 13. The number and size of the apertures 67 is a function of mass distribution. The function of the apertures 67 is to provide a substantially balanced and non-eccentric tolerance ring 65. It can be envisioned that the apertures 67 can have different shapes, such as, but not limited to, circle, square, triangle, polygon, or rectangle. Similarly, the apertures 67 can be distributed over one or more rows along the cylinder 13.
FIG. 12 is a perspective view of a tolerance ring 69 with cut-out feature for mass eccentricity control of the base portion. The tolerance ring 69 can have contacting portions 23 arranged in two or more rows around the surface of the cylinder 13 with an aperture, generally shown as 71, along the cylinder 13. The number and size of the apertures 71 is a function of mass distribution. The function of the apertures 71 is to provide a substantially balanced and non-eccentric tolerance ring 69. It can be envisioned that the apertures 71 can have different shapes, such as, but not limited to, circle, square, triangle, polygon, or rectangle. Similarly, the apertures 71 can be distributed over one or more rows along the cylinder 13.
It is understood by a person skilled in the art that any combination of the embodiments described herein can be used without departing from the purpose of the present invention. For example, a tolerance ring can have apertures 67 or 71 in combination with a tab 49 and aperture 51. Similarly, the tolerance ring can have apertures 67 or 71 in combination with a plurality of tabs 59 and a plurality of apertures 61. The tolerance ring can have apertures 67 or 71 along with hook-shaped tabs 27 and 29. All combinations of the described embodiments can be used to reduce mass imbalance and improve mass eccentricity of an actuator arm assembly.
Patent Application
20080049362
