Abstract
Multiple position switches and specifically in-line multiple position switches where a user has definitive points of on and off switching which are used to turn multiple redundant internal circuit switches on and off. This can provide for increased reliability of switch operation. The multi-position switch is typically a five-position switch with all five positions in-line and with double or triple redundancy at each position.
Claims
1. A multi-position switch comprising: a switch head; a button support attached to said switch head and configured to rotate to a first detent position located on a first side of a center position and a second detent position located on a second side opposing said first side of said center position; a first piston shaft connected to said button support and connected to a first roller positioned in a first rocker; a second piston shaft connected to said button support and connected to a second roller positioned in a second rocker; a first circuit switch arranged so as to be switched when said first rocker is rotated by said first roller as said button support rotates to said first detent position; a second circuit switch arranged so as to be switched when said second rocker is rotated by said second roller as said button support rotates to said second detent position; and a plunger located between said first piston shaft and said second piston shaft where depression of said button support in said center position causes said plunger to switch a third circuit switch.
2. The multi-position switch of claim 1 wherein said first circuit switch is one of a plurality of switches switched when said first rocker is rotated by said first roller as said button support rotates to said first detent position.
3. The multi-position switch of claim 2 wherein said second circuit switch is one of a plurality of switches switched when said second rocker is rotated by said second roller as said button support rotates to said second detent position.
4. The multi-position switch of claim 3 wherein said third circuit switch is one of a plurality of switches switched by said plunger when said button support in said center position is depressed.
5. The multi-position switch of claim 1 wherein said button support is configured to rotate from said first detent position to a third detent position located on said first side of said center position.
6. The multi-position switch of claim 5 further comprising: a fourth circuit switch arranged so as to be switched when said first rocker is rotated by said first roller as said button support rotates to said third detent position.
7. The multi-position switch of claim 6 wherein said button support is configured to rotate from said second detent position to a fourth detent position located on said second side of said center position.
8. The multi-position switch of claim 7 further comprising: a fifth circuit switch arranged so as to be switched when said second rocker is rotated by said second roller as said button support rotates to said fourth detent position.
9. The multi-position switch of claim 8 wherein said first circuit switch is one of a plurality of switches switched when said first rocker is rotated by said first roller as said button support rotates to said first detent position.
10. The multi-position switch of claim 9 wherein said second circuit switch is one of a plurality of switches switched when said second rocker is rotated by said second roller as said button support rotates to said second detent position.
11. The multi-position switch of claim 10 wherein said fourth circuit switch is one of a plurality of switches switched when said first rocker is rotated by said first roller as said button support rotates to said third detent position.
12. The multi-position switch of claim 11 wherein said fifth circuit switch is one of a plurality of switches switched when said second rocker is rotated by said second roller as said button support rotates to said fourth detent position.
13. The multi-position switch of claim 12 wherein said third circuit switch is one of a plurality of switches switched by said plunger when said button support in said center position is depressed.
14. The multi-position switch of claim 1 wherein said plunger includes a lower paddle portion and an upper tab, said upper tab interfacing with a plurality of detents on said button support as said button support moves from said center position to said first detent position and from said center position to said second detent position.
15. The multi-position switch of claim 14 wherein said lower paddle portion includes a lower segment and a narrower upper segment.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) FIG. 1 depicts a left top perspective view of a first embodiment of a multiple position switch.
(2) FIG. 2 depicts a bottom view of the multiple position switch of FIG. 1.
(3) FIG. 3 depicts a left side view of the multiple position switch of FIG. 1.
(4) FIG. 4 depicts a top view of the multiple position switch of FIG. 1 with no circuit switches activated (home position).
(5) FIG. 5A depicts a cut-through along line A-A in FIG. 4.
(6) FIG. 5B depicts a cut-through along line B-B in FIG. 4.
(7) FIG. 5C depicts a cut-through along line C-C in FIG. 4.
(8) FIG. 6 depicts a top view of the multiple position switch of FIG. 1 with the near forward linear position switches activated (first position).
(9) FIG. 7A depicts a cut-through along line K-K in FIG. 6.
(10) FIG. 7B depicts a cut-through along line L-L in FIG. 6.
(11) FIG. 7C depicts a cut-through along line M-M in FIG. 6. Note that FIG. 7C is in the opposite direction to FIGS. 7A and 7B which is why the switch appears to have been moved in the opposite direction even though it was not.
(12) FIG. 8 depicts a top view of the multiple position switch of FIG. 1 with the far forward linear position switches activated (second position).
(13) FIG. 9A depicts a cut-through along line N-N in FIG. 8.
(14) FIG. 9B depicts a cut-through along line P-P in FIG. 8.
(15) FIG. 9C depicts a cut-through along line R-R in FIG. 8. Note that FIG. 9C is in the opposite direction to FIGS. 9A and 9B which is why the switch appears to have been moved in the opposite direction even though it was not.
(16) FIG. 10 depicts a top view of the multiple position switch of FIG. 1 with the plunge switches activated (plunge position).
(17) FIG. 11A depicts a cut-through along line G-G in FIG. 10.
(18) FIG. 11B depicts a cut-through along line H-H in FIG. 10.
(19) FIG. 11C depicts a cut-through along line J-J in FIG. 10.
(20) FIG. 12 depicts a left top perspective view of a second embodiment of a multiple position switch.
(21) FIG. 13 depicts a cut-through image equivalent to that of FIG. 5B but on the embodiment of FIG. 12.
(22) FIG. 14 depicts a cut-through equivalent to that of FIG. 7B but on the embodiment of FIG. 12.
(23) FIG. 15 depicts a cut-through equivalent to that of FIG. 9B but on the embodiment of FIG. 12.
(24) FIG. 16 depicts a cut-through equivalent to that of FIG. 11B but on the embodiment of FIG. 12.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
(25) The following detailed description and disclosure illustrates by way of example and not by way of limitation. This description will clearly enable one skilled in the art to make and use the disclosed systems and methods, and describes several embodiments, adaptations, variations, alternatives and uses of the disclosed systems and methods. As various changes could be made in the above constructions without departing from the scope of the disclosures, it is intended that all matter contained in the description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
(26) While this disclosure will utilize terms such as “above”, “below”, “forward”, “back”, “left” or “right” these terms are used as a matter of convenience to describe the typical arrangement of a device when interacted with by a human user and are not intended to imply an absolute direction relative to the Earth or other body. For example, while a first object which is “below” a second object will typically be closer to the earth than the second object in routine operation, this is not intended to be required as the devices herein could be oriented in any direction relative to the Earth or relative to any gravitational field (or without one, such as in deep space). Instead, these terms are used to show relative positioning of objects to each other. Thus, if a third object was “above” the second object in the prior example, the three objects would typically be arranged generally linearly from the first object, to the second object, to the third object regardless of the various objects' positions in space. Similarly, an object on the right would be on a generally opposing side to an object on the left and movement forward would be in the generally opposing direction to movement backward.
(27) FIGS. 1 through 4 show various views of an embodiment of a five-position switch (100) which provides for five in-line “on” positions and a center “off” position. In particular, the switch (100) has two detents in one direction (which is called “forward” in this disclosure), two detents in opposite direction (which is called the “backward” direction in this disclosure) and a center plunge position. Each position of the switch (100) can activate one, two, three, or more circuit switches simultaneously providing it with multiple redundancy at virtually any level. This type of switch (100) with double or triple redundancy is well suited for mounting in a grip or similar component of an aircraft for activation by a pilot with their thumb. However, it may be used in any application which calls for a five-position switch.
(28) The switch of FIGS. 1 through 4 includes a housing (16). The switch head (101) extends therefrom. The switch head (101) is the portion of the switch that is intended to be human activated. As such it may be any form of object which is designed to be pushed or pulled by a human. In the depicted embodiment, the switch head (101) comprises a generally square or “squircle” shape in cross section. The upper surface (103) thereof is typically concave in at least one major dimension. As shown in the switch (1000) of the alternative embodiment of FIGS. 12-16, the switch head (101) may include knurling or texturing (113) to increase friction when contacted by a finger or thumb the pad of which would typically be placed into the concave surface (103). The switch head (101) is surrounded by a cowl (105) which is designed to allow the head (101) to move relative to the housing (16) while still keeping objects (including dust and dirt) and moisture out of the housing (16).
(29) At the lower portion of the housing, there are mounted a number of circuit switches (201), (203), (205), (207), (209), (211), (213), (215), (217) and (219). In the depicted embodiment, there are ten such circuit switches (201), (203), (205), (207), (209), (211), (213), (215), (217) and (219) depicted. As this is a five-position switch, each “on” position will activate two of the circuit switches (201), (203), (205), (207), (209), (211), (213), (215), (217) and (219) compared to other positions which provides each position with double redundancy. The circuit switches (201), (203), (205), (207), (209), (211), (213), (215), (217) and (219) are paired with circuit switches (201) and (211) being together, circuit switches (203) and (213) being together, circuit switches (205) and (215) being together, circuit switches (207) and (217) being together, and circuit switches (209) and (219) being together. It should be apparent that each pair of switches could be replaced by a single circuit switch, or by three or more circuit switches if a different level of redundancy is desired. Each of the circuit switches (201), (203), (205), (207), (209), (211), (213), (215), (217) and (219) will generally comprise a micro or sub-micro button switch such as, but not limited to, the B1 basic series of switches or the B3 basic series of switches produced by Otto. This particular type of switch is, however, by no means required and any sort of circuit switch activated by the motion of the switch (100) discussed herein may be used.
(30) The head (101) typically has five different linear positions into which it may be placed. In FIGS. 4 and 10, the head (101) is shown in a center position. In FIG. 4 the head (101) is not depressed so the switch (100) is in the off or home position. In FIG. 10 the head (101) is depressed and is in the plunge position. FIG. 6 shows the head (101) in a first detent position which in this embodiment is also referred to as a near forward position. FIG. 8 then shows the head (101) in the second detent position or far forward position. The use of the terms “near” and “far” are arbitrary here and are simply used to indicate that the head (101) in a far position is further from the center than in a near position.
(31) The switch (100) will now be discussed in conjunction with the various internal components. The structure of the internals of the switch (100) are best seen by Examining the series of FIGS. 5A, 5B, and 5C; the series of FIGS. 7A, 7B, and 7C; the series of FIGS. 9A, 9B, and 9C; or the series of FIGS. 11A, 11B, and 11C as each of these shows cut-through drawings of the switch at various lines as indicated in the respective FIGS. 4, 6, 8, and 10. For ease of discussion and display, FIGS. 5A, 5B, and 5C have been labeled with all the various structural components while FIGS. 7A, 7B, 7C, 9A, 9B, 9C, 11A, 11B, and 11C only have a subset of components labeled to assist in showing relative positioning.
(32) There is further provided an alternative embodiment which is provided in FIGS. 12-16. This alternative embodiment is generally similar to the other embodiment of FIGS. 1-11C however the head (101) is textured (113) as contemplated above and the alternative embodiment utilizes a different shape of plunger (20). The plunger (20) in FIGS. 12-16 has a paddle portion (1402) that is generally different to paddle portion (402) to provide for some structural differences and improved functionality in certain situations. However, the function of the switch (1000) and the switch (100) are typically similar and may be identical. Further, as viewed externally the two switches (1000) and (100) may be identical in operation. Further, they share many similar components. For this reason, FIGS. 13-16 are essentially designed to replace FIGS. 5B, 7B, 9B, and 11B if one was to view switch (1000) instead of switch (100) with the relevant structures of the remaining FIGS. being essentially the same in both embodiments.
(33) As can be seen in FIGS. 5A, 5B, and 5C, the head (101) is attached to a button connector (17). The button connector (17) has three distinct portions which may be co-molded or separate. On either side of center, as viewed, for example, in FIGS. 5A and 5C, the button connector (17) has an extending piston shaft (301) and (303). Each of these then interfaces with a roller shaft (311) or (313) respectively to form a compression piston (31) and (33). Compression coil or wave springs (321) and (323) serve to bias the pistons (31) and (33) to exhibit force pushing downward. At the terminal end of the roller shaft (311) or (313) there is provided a roller (331) and (333).
(34) The central portion of the button connector (17) includes a generally concave lower surface (401) having three generally semi-circular divots (411), (413), and (415) therein. The central divot (411) is typically located in generally the center of the concave lower surface (401) with each of divots (413) and (415) being arranged on the forward and backward side thereof. Under the concave lower surface (401) there is positioned a plunger (20) which, in the embodiment of FIGS. 5A, 5B, and 5C, comprises a lower paddle portion (402) and an upper tab (412) which is typically integrally formed therewith. In the depicted embodiment of FIGS. 5A, 5B, and 5C, the plunger (20) may interact with a spring (10) and ball bearing (1) system to assist in holding the plunger (20) in position while allowing the plunger (20) to move freely up and down within the housing (16), but this is by no means required and may be removed in an alternative embodiment.
(35) In the alternative embodiment of FIGS. 13-16, the plunger (20) includes the upper tab (412). However, the lower paddle portion (1402) has a more complex shape. The lower paddle portion (1402) is generally in the shape of a cross section of a “top hat” and has a lower segment (1412), and an upper segment (1422) where the upper segment is narrower (as viewed in FIGS. 13-16) than the lower segment. The upper segment then uses a step (1432) to interconnect with the upper tab (412). Comparing, for example, FIG. 13 to FIG. 5B, it should be apparent that the lower segment (1412) has similar width to the paddle portion (402). However, including the narrower upper segment (1422) allows for the switch (1000) of FIGS. 13-16 to include a larger channel guide (1501) that the narrower upper segment (1422) can interface with. This provides a lower stop edge (1503) which the upper edge (1403) of the lower segment (1412) will impact when the plunger (20) of FIGS. 13-16 retracts. The channel guide (1501) also includes a cutout segment (1532) which is designed to accept the step (1432). The structure of lower paddle portion (1402) can assist in providing for straighter plunge motion of the plunger (20) in certain embodiments.
(36) In both embodiments, the upper tab (412) typically includes a generally semi-circular top surface (424) which is generally dimensioned to have a radius similar to the radius of the divots (411), (413) and (415). The plunger (20) is positioned above a compression coil or wave spring (9) which serves to bias the plunger (20) toward the button connector (17) and away from circuit switches (209) and (219) which are positioned below the lower edge (429) of the paddle portion (402) or (1402). There is a central stabilizing pin (4) which runs through a raceway (441) in the plunger (20) allowing the plunger (20) to move up and down against the spring (9) in a straight line. The pin (4) extends through the pistons (30) and (31) and is typically attached to the housing (16) to act as an axis of rotation for the button connector (17) relative to the housing (16) via the pistons (30) and (31).
(37) Below each of the rollers (331) and (333) there is positioned a rocker (351) and (353). The rockers (351) and (353) are of distinctly different shape but have some common design features. Each rocker (351) and (353) is supported on two pins (361) or (363) which are typically rigidly attached to the housing (16) as shown for pins (361) in FIG. 3. Rocker (351) is supported on pins (361) and rocker (353) is supported on pins (363). It should be apparent from the FIGS. That pins (361) are positioned at a greater distance from each other than pins (363).
(38) Each rocker (351) and (353) include a concave upper surface forming a track (371) and (373) into which the respective roller (331) and (333) is positioned and can roll. The track (373) will typically have steeper surfaces as well as potentially longer surfaces than track (371) as is visible from comparing FIG. 5A to FIG. 5C. The tracks (371) and (373) are typically generally not semicircular or of consistent radius. The track (373) will often be more parabolic than the track (371). The tracks (371) will also typically include at least two different radii depending on the location within the track (371) or (373).
(39) Track (371) will typically include a first area (381) forming the lowest area. There is then a slightly raised portion or “bump” (382) followed by the higher area (383). This structure is by no means required, but it can improve the feel of movement as discussed later. This structure of track (371) provides multiple areas where the roller (331) can be. The roller (331) can be in the first area (381) where it is stable and pushed toward center by the track (371) and spring (331), it can be rolling up the raised portion (382) where the spring (321) will typically serve to try and push it back toward the first area (381), it can be on the far side of the raised portion (382) where it will be pushed toward the higher area (383), or will be in the higher area (383). Track (373) will typically include a first area (391) which acts as a sort of bowl at the lowest area of the track (373) and the steep sides (393). It may also include a raised area or bump between them in another embodiment.
(40) Operationally the switch (100) will provide for five different “on” positions. These correspond to depressing the pair of circuit switches (201) and (211); (203) and (213); (205) and (215); (207) and (217); or (209) and (219) and a single “off” or home position. FIGS. 5A, 5B, and 5C show the home position where both the rockers (351) and (353) are positioned resting on both of their respective pins (361) and (363). The rollers (331) and (333) are positioned in the low areas (381) and (391) generally centered between the pins (361) or (363) and the plunger (20) is biased above the circuit switches (209) and (219). As can be seen, none of circuit switches (201), (203), (205), (207), (209), (211), (213), (215), (217) and (219) have been depressed, so they are all “off”.
(41) FIG. 6 illustrates moving the head (101) to the near forward position where it has been moved slightly forward from the home position of FIG. 4. FIGS. 7A, 7B, and 7C illustrate the movement of the interior components. The head (101) has moved through an angle of about 10 degrees, but this is not required and any rotation amount could be bused in alternative embodiments. The rotation is typically around pin (4). In moving to this position, the roller (331) has rolled up the track (371) and is around the raised area (382). However, the rocker (351) still rests on both pins (361A) and (361B) as the biasing of spring (321) is directed to low on rocker (351) to tip rocker (351). The roller (333) has also rolled up the track (373) and is now on the higher area (393). This has caused the rocker (353) to be tipped by the biasing force of the spring (323) so rocker (353) only rests on the single pin (363A) and has lifted off of pin (363B). This tipping has resulted in the rocker (353) depressing circuit switch (201) (and circuit switch (211) which is next to it but not visible). The tipping, however, has not resulted in the rocker (351) depressing circuit switch (203) (or circuit switch (213) which is next to it but not visible)
(42) It should be apparent, that movement from the home position of FIG. 4 to the near forward position of FIG. 6 does require the user to apply some force to the head (101). In particular, the head (101) requires sufficient force to move the roller (331) up the raised portion (382), start pushing the roller (333) up the steeper area (393) and push the top (424) of the plunger (20) downward. The top (424) of the plunger (20) has also now entered divot (415) which provides a clear feel for the user when this position is reached. However, it is important to note that the plunger (20) has not been deflected enough to contact circuit switches (209) and (219) yet. Typically, the force to activate the switch to this near forward position of FIG. 6 is around 1-2.5 lbs. more preferably around 1-2 lbs. This position also feels stable to the user as a clear specific position, but is not actually stable. Should the user release the head (101), the head (101) would return to the home position of FIG. 4 due to the force of the biasing by springs (321), (323) and (9) as well as the shapes of the rockers (351) and (353).
(43) If the user continues to push the head (101) in the forward direction, it will place the head (101) into the far forward configuration of FIG. 8. At the far forward position, the head (101), in this embodiment, is at a generally 20 degree rotation around pin (4) but this is not required and it could be any amount of rotation greater than that of the near forward position. Moving the head (101) to the far forward position will typically take additional force by the user. Typically, this is about 0.5 to 1.5 lbs. more than near forward position.
(44) In the far forward position, as can be seen in FIGS. 9A, 9B, and 9C, the roller (333) has continued up the steeper area (393) but the rocker (333) has not tilted any further as it is held in place by the circuit switch (201) which inhibits further movement. Instead, the spring (323) has been additionally compressed by the movement. Roller (331), however, has now gotten onto the higher area (383) which has caused the rocker (351) to tip over pin (361A) and leave contact with pin (361B). This has now caused the rocker (351) to depress circuit switch (203) (and circuit switch (213) which is next to it but not visible). Feel for this position may be provided by the contact between the button (17) and the edge of the housing (16) which can be seen toward the left of FIGS. 9A and 9B and the right of FIG. 9C. Note that circuit switches (201) and (211) are still depressed in the far forward position. However, the new depression of circuit switches (203) and (213) makes this a new “on” position.
(45) From the far forward position of FIG. 8, the head (101) will still return to center (the home position of FIG. 4) if the user lets up on the pushing force at any point due to the biasing of springs (321), (323) and (9). Due to the presence of the coil springs (321), (323), and (9) along with the divots (411), (413), and (415) and the variations in the tracks (371) and (373) the activation of the present switch feels like a snap action mechanism for movement to any of the near forward or far forward positions from any other position.
(46) While FIGS. 6 and 8 illustrate the near and far forward positions, it should be apparent that the switch head (101) can be moved the opposing (backward) direction (toward the right of the page in FIGS. 4, 6, and 8) which will produce two similar near backward and far backward positions which are essentially mirror images of the positions in FIGS. 7A, 7B, 7C, 9A, 9B, and 9C. Basically, the motion is the same except that the rockers (351) and (353) tip over pins (361B) and (363B) leaving their connection with pins (361A) and (363A) and switch pairs (205) (215) and (207) (217) are activated. This produces four different “on” positions for the switch (100). To put this another way, if the near forward position comprises tilting the head 10 degrees and the far forward position comprises tilting the head 20 degrees, the near backward position would typically comprise tilting the head (101) −10 degrees and the far backward position comprises tilting the head (101) −20 degrees.
(47) Regardless of position (near forward, far forward, near backward, or far backward), it should be apparent that the circuit switches associated with each position activate simultaneously. Thus, with double redundancy, the circuit switches in each pair (201) and (211); (203) and (213); (205) and (215); (207) and (217); or (209) and (219) are being depressed by the respective rocker at essentially the same time. Further, in order to increase redundancy, additional circuit switches may be placed beside either of the existing circuit switches in any or all of pair (201) and (211); (203) and (213); (205) and (215); (207) and (217); or (209) and (219) to produce additional redundancy at any position.
(48) The fifth position of the switch (100) is produced with the head (101) centered as shown in FIG. 10, but the head (100) is depressed a short distance directly into the housing (16). This plunge position is shown in FIGS. 11A, 11B, and 11C. As can be best seen in FIG. 11B, pushing the head (101) straight down from the center position results in the concave base (401) pushing the top (424) (which is in divot (411)) downward and against the biasing of spring (9). This causes the entire plunger (20) to depress and the bottom (429) of the paddle (402) to depress the circuit switch (209) and (219) generally simultaneously.
(49) As can also be seen from FIGS. 11A, and 11C, depression of the button (17) when centered simply causes the two pistons (30) and (31) to compress against springs (321) and (323). However, because the rollers (331) and (333) are currently centered on the tracks (371) and (373) of the rockers (351) and (353), the rockers (351) and (353) are not encouraged to tip in any direction. Instead, the increased force simply pushes each of the rockers (351) and (353) into their respective pin pair (361) or (363). Thus, in the plunge position of FIG. 10, only the center pair of circuit switches (209) and (219) are activated. This plunge position provides the fifth “on” position. It should be apparent, that if the user lets up force from this depression, the springs (321), (323), and (9) will bias the button (17) and the head (101) back to the home position of FIG. 4.
(50) In the embodiment of the present FIGS, the plunge position which the paddle (402) of the plunger (20) depressing the circuit switches (209) and (219) is only available when the head (101) is centered as in FIG. 11. This is because the head (101) and/or button (17) may be blocked from downward movement when the head (101) has been rotated to the relevant angles for the near or far forward or backward positions. This block may be through simple shaping of the button (17) and housing (16) or there may be included barriers within or on the housing (16) and/or button (17) to inhibit such motion. However, in an alternative embodiment, the plunge activation (namely the paddle (402) bottom (429) depressing circuit switches (209) and (219)) may occur at any or all of the near forward, far forward, near backward, or far backward positions by simply pushing the head (101) downward toward the housing (16) while holding the head (101) in the tilted angle corresponding to that position.
(51) While the invention has been disclosed in conjunction with a description of certain embodiments, the detailed description is intended to be illustrative and should not be understood to limit the scope of the present disclosure. As would be understood by one of ordinary skill in the art, embodiments other than those described in detail herein are encompassed by the disclosed invention. Modifications and variations of the described embodiments may be made without departing from the spirit and scope of the invention.
(52) It will further be understood that any of the ranges, values, properties, or characteristics given for any single component of the present disclosure can be used interchangeably with any ranges, values, properties, or characteristics given for any of the other components of the disclosure, where compatible, to form an embodiment having defined values for each of the components, as given herein throughout. Further, ranges provided for a genus or a category can also be applied to species within the genus or members of the category unless otherwise noted.
(53) Finally, the qualifier “generally,” and similar qualifiers as used in the present case, would be understood by one of ordinary skill in the art to accommodate recognizable attempts to conform a device to the qualified term, which may nevertheless fall short of doing so. This is because terms such as “circular” are purely geometric constructs and no real-world component is truly “circular” in the geometric sense. Variations from geometric and mathematical descriptions are unavoidable due to, among other things, manufacturing tolerances resulting in shape variations, defects and imperfections, non-uniform thermal expansion, and natural wear. Moreover, there exists for every object a level of magnification at which geometric and mathematical descriptors fail due to the nature of matter. One of ordinary skill would thus understand the term “generally” and relationships contemplated herein regardless of the inclusion of such qualifiers to include a range of variations from the literal geometric meaning of the term in view of these and other considerations.
