1. Field of the Invention
The present invention relates generally to electrical switch assemblies. More specifically, the present invention concerns a preferably waterproof switch having a uniform tactile feel.
2. Discussion of Prior Art
Those ordinarily skilled in the user actuatable switch assembly art will appreciate the broad utility of user depressible switch assemblies with one example of such assemblies being touchpad switch assemblies commonly used in the automotive industry. Notably, a user actuates such touchpad switch assemblies by depressing the touchpad a predetermined distance to engage a tact switch, elastomeric or metal dome switch, or the like. The switch is operably part of the final switch assembly and provides a tactile feel depending on the configuration and design of the switch. Importantly, a uniform tactile feel across the entire touchpad area is desired. Such uniformity may be difficult to obtain, however, because standard touchpad applications are sufficiently dimensioned to ensure actuation. In some instances, touchpad switch assemblies are configured to be operated by a plurality of fingers, such as, for instance, three fingers.
However, conventional large touchpad applications are problematic. For instance, if the assembly is provided with a single switch, actuation of the switch is not assured, particularly when one end of the touchpad is pressed by the user. With prior art switch assembly designs, the touchpad (or underlying actuator) can become canted or otherwise simply fail to actuate the switch. Furthermore, uneven movement of the shiftable portion of the switch assembly provides the user with unreliable tactile feedback as to whether the switch assembly has been actuated. Some conventional switch assemblies are provided with multiple switches spaced along the touchpad. However, this design requires signal debouncing when more than one of the switches is actuated by the user.
Moreover, as a result of the broad utility of user depressible switch assemblies, switch assemblies are exposed to, and must preferably withstand, a broad array of environmental and weather conditions. For instance, automotive touchpads experience large temperature ranges, rain, snow, and high-pressure car washes, thus requiring touchpads to be reliably sealed by employing various manufacturing techniques to protect the switch from such conditions, which may deteriorate and/or compromise the performance or functionality of the switch assembly. Sealing techniques are therefore preferable to protect the switch assembly and may be achieved by rubber and/or plastic over-molded parts, seal beading techniques, liquid adhesives, room temperature vulcanization techniques, epoxies, and the like. Application of such sealing techniques can, however, present manufacturing difficulties. For instance, reliable and repeatable sealing with epoxy presents challenges of consistently applying the epoxy in the desired sealing locations without presenting air bubbles and other voids that potentially denigrate the quality of the desired seal. Moreover, improved application of sealant commonly requires a moving applicator to appropriately seal various locations spaced apart on the switch assembly. But dynamic or moving sealant applicators introduce reliability and/or efficiency difficulties in the manufacturing process, which, again, may deteriorate and/or compromise the performance or functionality of the seal and, therefore, the switch assembly.
Responsive to these and other problems, an important object of the present invention is to provide a preferably waterproof switch having a uniform tactile feel.
According to a first aspect of the present invention, a manually operated switch assembly broadly includes a housing, a switch mechanism, and an actuator assembly. The switch mechanism is housed within the housing and is configured to open or close a circuit upon actuation. The actuator assembly is shiftably supported by the housing and generally includes a depressible actuator and a stability element. The depressible actuator is configured to be manually depressed when the switch assembly is operated. The actuator presents an actuator length and serves to actuate the switch mechanism when depressed. The stability element is configured to ensure that the actuator moves substantially uniformly along the actuator length when the actuator is depressed such that actuation of the switch mechanism is facilitated regardless of where the actuator is depressed along the actuator length.
Another aspect of the present invention concerns a waterproof manually operated switch assembly formed at least in part by a curable liquid sealant supplied to the switch assembly from a single sealant source. The waterproof switch assembly broadly includes a switch mechanism, and a housing. The switch mechanism is housed within the housing and configured to open or close a circuit upon actuation. The housing presents first and second openings. The first opening is configured to receive liquid sealant from the sealant source. The second opening is spaced from the first opening. A sealant transfer channel is defined by the housing and extends between the first and second openings to define a liquid sealant flow path between the first and second openings. The liquid sealant supplied to the first opening flows along the transfer channel into the second opening. Thus, the first and second openings contain cured sealant, with the sealant in the second opening having been supplied from the first opening.
Other aspects and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments and the accompanying drawing figures.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description of the preferred embodiments. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
Preferred embodiments of the invention are described in detail below with reference to the attached drawing figures, wherein:
The drawing figures do not limit the present invention to the specific embodiments disclosed and described herein. The drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the preferred embodiment.
With reference to the drawings, wherein like reference numerals designate like parts and assemblies throughout the several views,
The switch assembly 20 broadly includes a housing 22, a switch mechanism 24, an actuator assembly 26, and a flexible pad 28. With particular reference to
The inner wall surface 56 and the inner floor surface 46 cooperatively define an actuation chamber 58 having a depth configured to shiftably receive the actuator assembly 26. In particular, located at the center of the length of the inner floor surface 46 is a generally circularly shaped switch mechanism aperture 60 that is dimensioned to receive a portion of the switch mechanism 24 as further described below. Likewise, the inner floor surface 46 presents a pair of switch mechanism alignment slots 62,64, with each alignment slot 62,64 being spaced from the switch mechanism aperture 60 on opposing sides thereof along the inner floor surface 46. Although the inner floor surface 46 is shown presenting various contours, those of ordinary skill in the art will appreciate that the contours may be varied, or indeed nonexistent, depending upon the design needs of the switch assembly 20.
The periphery of the inner wall surface 56 presents a plurality of inwardly projecting rails 66,68,70,72,74 that preferably extend transversely from the inner floor surface 46. The rails 66,68,70,72,74 preferably extend vertically along only part of the top wall portion 50, although those components could alternatively be coextensive if desired. In particular, two end rails 66,68 are located at respective ends 38,40 of the floor 42 and extend substantially vertically from the inner floor surface 46 along the inner wall surface 56. A set of three central rails 70,72,74 are located more proximate the switch mechanism aperture 60 and, like the end rails 66,68, extend substantially vertically from the inner floor surface 46 along the inner wall surface 56. Two of the central rails 72,74 are located on one side of the inner wall surface 56. The third central rail 70 is located on the opposite side of the inner wall surface 56. In this manner, the central rails 70,72,74 are oriented around the switch mechanism aperture 60 at intervals of approximately 120° from each other. Each of the rails 66,68,70,72,74 terminate in a generally flat top surface 76. Finally, the inner wall surface 56 presents four spaced abutments 78,80,82,84 extending from the inner floor surface 46. Each abutment 78,80,82,84 extends along part of the height of the upright wall 48, but to a height generally shorter than each of the respective 66,68,70,72,74 rails. The top surface 86 presented by each abutment 78,80,82,84 is generally flat.
The inner floor surface 46 presents a pair of respective anchor columns 88,90 at opposite common corners of the floor 42. Each of the anchor columns 88,90 extend substantially vertically from the inner floor surface 46 along the inner wall surface 56 and terminate at a generally flat top 92. Near the top of each anchor column 88,90 are respective inwardly facing bores 94,96. Each bore 94,96 is aligned with respect to the other to be located at a common height and present an axis 98 defining a pivot location. One of the illustrated anchor columns 88 includes a sloped ramp 100 leading to its respective bore 94. As will be seen, each of the rails 66,68,70,72,74, abutments 78,80,82,84, anchor columns 88,90, and bores 94,96 cooperatively interact with the actuator assembly 26 to ensure proper fitment, alignment, and shifting of the actuator assembly 26 when the switch assembly 20 is in use. Further, while the illustrated rails 66,68,70,72,74, abutments 78,80,82,84, and anchor columns 88,90 are preferably integrally formed with the case 30 at particular locations therein, those of ordinary skill in the art will recognize that the rails 66,68,70,72,74, abutments 78,80,82,84, and anchor columns 88,90 may be separately formed and joined to the case 30. Moreover, the relative spacing, and respective heights and locations of the rails 66,68,70,72,74, abutments 78,80,82,84, and anchor columns 88,90 may be variously configured without departing from the scope of the embodiments claimed herein.
Still referring generally to
Four securement tabs 122,124,126,128 are similarly spaced along the periphery of the outer wall surface 54. More particularly, each side of the case 30 has a pair of securement tabs projecting downwardly from the outer wall surface 54 and terminating in outwardly facing hooks 142,144,146,148. Each securement tab 122,124,126,128 is preferably resiliently flexible in such a manner so that when the case 30 is mountably coupled to a vehicle or the like, each of the securement tabs 122,124,126,128 resiliently flexes until the hooks 142,144,146,148 are engageable with the vehicle to secure the case 30 to the vehicle for use. Those of ordinary skill in the art will recognize that the switch assembly 20 may be alternatively configured for attachment to the corresponding structure. For example, any of a plurality of mechanisms, structures, and bonding agents may be used to couple the case 30 to an object, such as a vehicle, for use therewith.
The bottom portion of the wall 52 generally includes two spaced apart wall sections 150,152. Each of the wall sections 150,152 is generally shorter than the length of the case 30 and only extends partly along the length of the case 30. The illustrated wall sections 150,152 are generally centrally located with respect to the floor 42 of the case 30. Moreover, each wall section 150,152 presents an outwardly facing rounded top edge 154,156. Thus, the outer wall surface 154 is cooperatively defined by both the top wall portion 50 and the bottom wall portion 52 of the wall 48.
Each side 34,36 of the case 30 presents a pair of spacers 158,160,162,164 projecting substantially perpendicularly from the outer wall surface 54 and being joined by respective channel walls 118,120 having an outer surface 166 and an inner surface 168. The spacers 158,160,162,164 and channel walls 118,120 extend downwardly beyond the outer floor surface 44. Spaced on opposite sides of the switch mechanism aperture 60 are a pair of cross-walls 170,172 projecting from the outer floor surface 44 and intersecting the sections of the bottom wall portion 52 to cooperatively define a switch mechanism compartment 174. The cross-walls 170,172 are preferably aligned with the spacers 158,160,162,164 and serve to integrate the channel walls 118,120. The cross-walls 170,172 each have inner 176,178 and outer 180,182 surfaces extending downwardly from the outer floor surface 44 and across the width of the case 30. In this manner, the channel walls 118,120 and respective cross-walls 170,172 form an integral channel frame 184 having a depth below the floor. The frame 184 is generally square in shape and presents an internal frame area 186. Within the frame area 186, on each side of the case 30, each wall section of 150,152 the bottom wall portion 52 extends downwardly beyond the outer floor surface 44 in a substantially parallel orientation with respective channel walls 118,120, and terminates at a depth shallower than the depth of the frame 184. Thus, the inner surface 168 of the channel wall is spaced from the outer wall surface 54 of the respective section of the wall portion to thereby define channels 188,190 on opposite sides of the case 30, with the channels 188,190 extending from the bottom of the tapered upright wall to the top of the channel walls 118,120.
The peripheral bottom wall portion 52 extending below the floor 42 of the case 30, the inner wall surfaces 176,178 of the cross-walls 170,172, and the outer floor surface 44 cooperatively define a switch opening 192 at the bottom of the switch compartment 174. The opposing inner wall surfaces 176,178 of the cross-walls 170,172 present identical inwardly facing tapered lock tabs 194, which are configured to retain the switch mechanism 24 within the switch compartment 174. In addition, the outer floor surface 44 includes a downwardly projecting switch aperture collar 196 that circumscribes the periphery of the switch aperture 60. Likewise, the outer floor surface 44 presents ridges 198 circumscribing the periphery of each of the alignment slots 62,64 located on opposing sides of the switch aperture 60.
The latching ring 32 generally includes a generally rectangularly shaped frame wall 200 having two ends 202,204 with a length therebetween. The frame wall 200 presents an inner 206 and outer 208 surface. The substantial length of the frame wall 200 is shorter than respective ends thereof. The lower edge of the frame wall includes slots 210,212,214,216 at each of the four corners, with each slot 210,212,214,216 being sized to receive respective ones of the stop tabs 102,104,106,108 projecting from the outer surface 54 of the wall 48 of the case 30. Likewise, adjacent the slots 210,212,214,216 are respective latch apertures 218,220,222,224, each of which is dimensioned to receive respective securement tabs 122,124,126,128 projecting from the outer surface 54 of the wall 48 of the case 30. The circumference of the frame wall 200 is so dimensioned to extend around the periphery of, and be spaced from, the outer wall surface 54 of the case 30. The frame wall 200 is joined to the outer wall surface 54 of the case 30, such that the case 30 and latching ring 32 cooperatively form the housing 22 of the switch assembly 20. In this manner, the cooperation of the latching ring tabs 110,112,114,116 with the latching apertures 218,220,222,224 and the slots 210,212,214,216 with the stop tabs 102,104,106,108 ensure proper alignment and fitment of the latching ring 32 about the case 30 to form the housing 22. Moreover, the assembled housing 22 defines a generally circumferential opening circumscribing the case 30, with the circumferential opening being defined between the outer surface 54 of the wall 48 of the case 30 and the inner surface 206 of the latching ring 32 (see, e.g.,
Now referring generally to
The illustrated switch 226 includes top 244 and bottom 246 surfaces. The bottom surface 246 of the switch is mechanically supported by the top surface 230 of the contact board 228. The top surface 244 of the switch 226 preferably includes a pair of generally trapezoidally-shaped projections 248,250, with each projection 248,250 extending substantially perpendicularly from the top surface 244 thereof. The illustrated switch 226 preferably includes a rubber dome 252 located midway between each of the respective projections 248,250 and extends substantially perpendicularly from the top surface 244 of the switch 226. In particular, the illustrated dome 252 is preferably formed of rubber, silicone, or the like, and capable of withstanding a suitable number of depression cycles given the design goals of the switch assembly 20. Indeed, the dome 252 is preferably resilient such that forces applied to the dome 252 cause the dome 252 to compressibly and resiliently flex, operatively opening or closing the circuit defined in part by the switch 226 and/or the contact board 228 supporting the switch 226. Moreover, when compressive forces are no longer applied to the dome 252, the dome 252 resiliently springs back to its initial non-depressed state. One of ordinary skill in the art will appreciate that any suitable one of a variety of switches, such as tact, push-button, toggle, momentary, and the like, may operatively be used with the switch assembly 20 described herein. Moreover, while the switch mechanism 24 illustrated herein only contains a single switch 226, a plurality of switches may operatively be utilized thereon without departing from the ambit of the present invention.
The illustrated switch mechanism 24 is preferably configured to be matingly received within the switch opening 192. In particular, the switch 226 is inserted so that the dome 252 of the switch 226 is received and protrudes through the switch aperture 60. When properly oriented, the projections 248,250 protrude through the switch mechanism alignment slots 62,64. In this manner, the switch mechanism 24 is properly oriented within the switch compartment 174. Further, the switch mechanism 24 is operatively snapped into place within the switch compartment 174 by virtue of the identical tapered lock tabs 194, Thus, once assembled, the dome 252 is accessible through the switch aperture 60 and the lead wires 240,242 protrude from the switch compartment 174, and the switch mechanism 24 is preferably permanently retained in the switch opening 192 by the lock tabs 194.
Referring now generally to
The peripheral edge 274 of the actuator body 258 includes a plurality of vertical slots 286,288,290,292,294 therein. For instance, a set of three spaced vertical slots 290,292,294 are located along the periphery of the platform 262 and extend from the top surface 272 to the bottom surface of the actuator body 258. In the illustrated embodiment two of the slots 292,294 are located opposite a single remaining 290 slot on the opposite side thereof. Moreover, respective end slots 286,288 are located on each of the respective risers 264,266 and extend from the bottom surface of the risers 264,266, but preferably do not extend to the top surface 272 of the risers 264,266. Further, the bottom surface of the platform 262 presents four ledges 296,298,300,302 defined by the peripheral edge 274 of the actuator body 258 and the bottom surface of the platform 262. As will be described further herein, each of these vertical slots 286,288,290,292,294 and ledges 296,298,300,302 cooperate with respective rails 66,68,70,72,74 and abutments 78,80,82,84 of the case 30 to ensure proper alignment, fitment, and proper sliding action of the actuator 254 relative to the housing 22.
The illustrated actuator cap 260 is generally rectangularly-shaped and has a length between respective ends thereof. The cap 260 presents generally flat top 304 and bottom 306 surfaces. The bottom surface 306 of the actuator cap 260 preferably presents downwardly projecting, hollow, cylindrically shaped projections 308,310 at opposing ends of the cap 260. Each of the projections 308,310 preferably extends substantially perpendicular from the bottom surface 306 of the actuator cap 260 and is so dimensioned to be received in respective pits 278,280 on the top surface 272 of the actuator body 258. In this manner, an actuator channel 312 is thereby defined by the bottom surface 306 of the actuator cap 260 and the depression 276 formed along the length of the platform 262 of the actuator body 258. Moreover, while the actuator cap 260 selected for illustration herein substantially covers the entire top surface 272 of the actuator body 258, those of ordinary skill in the art will readily recognize that the actuator cap 260 may be variously configured and may only cover a portion of the platform 262. Additionally, the actuator cap 260 may be coupled and/or secured to the actuator body 258 with a variety of known mechanical structures and/or adhesive compounds or elements.
The stability element 256 selected for illustration herein is generally cylindrical in cross-section and u-shaped. Specifically, the preferred element 256 has a pair of end prongs 314,316 and a substantially straight bight 318 extending therebetween. In particular, the end prongs 314,316 of the stability element 256 are substantially coaxially oriented to define a pivot 320 of the element 256, as will be described. The bight 318 is spaced from the axis by respective vertical legs 322,324 joining the end prongs 314,316 to the substantially straight bight 318. While the depicted stability element 256 is formed of metal, the stability element 256 may be formed of any suitably rigid material.
Referring now to
Those of ordinary skill in the art will readily recognize that various other structures may be present to facilitate assembly of the actuator assembly 26 with the case 30. In particular, either or both of the anchor columns 88,90 may include a sloped ramp to facilitate insertion of the end prongs 314,316 within respective bores 94,96. Moreover, variously configured vertical slot and rail configurations, and varying tolerances to adjust how snugly the actuator assembly 26 is received within the case 30 may be implemented to achieve desired results. Indeed, although the illustrated case 30 and actuator body 258 present a number of cooperating slots and rails, those of ordinary skill in the art will appreciate that embodiments of the switch assembly 20 may not include any such structure. Furthermore, the switch mechanism 24 may be alternatively designed to present a plurality of domes, each of which may be actuatable by the actuator assembly 26.
Referring now generally to
Operational views of the switch assembly 20 are particularly illustrated in
More particularly, with the end prongs 314,316 of the stability element 256 rotatably anchored to the case, the stability element 256 is limited to swinging about the pivot axis defined by the end prongs 314,316. As the stability element 256 pivots, the bight 318 slides within the actuator channel 312 (compare
Additionally, operational views demonstrating how a curable liquid sealant 348 may operably be applied to the switch assembly 20 from a single sealant source (not shown) is illustrated in
In any event, as the switch opening 192 is filled with liquid sealant 348, the liquid sealant 348 approaches the end (top) of the tapered upright wall portions 150,152. The contact board 228 serves as a floor for the switch opening 192, such that sealant 348 is contained between the board 228 and the inside surfaces 176,178 of the cross-walls 170,172 and the bottom wall portion 52 of the upright wall 48. Upon continued application of liquid sealant 348, the liquid sealant 348 will then flow over the wall portions 150,152 and begin to flow through the channels 188,190 by force of gravity. Thus, the overflow sealant is transferred to the lower circumferential 350 opening as illustrated in
Those of ordinary skill in the art will immediately recognize that the housing 22 and liquid sealant 348 arrangement may be variously configured and still be within the ambit of the present invention. For instance, the openings requiring sealant may number in excess of two, and the channels providing fluid transfer between various openings may be more or less numerous than the two channels illustrated herein. It is also not necessary for one opening to be higher than another so that gravity is designed to effect liquid sealant flow from one opening to another. For example, the switch assembly 20 could alternatively be designed to house a closed channel so that the sealant 348 is pumped under pressure through the channel and into the second opening.
The switch assembly 20 is preferably retained inverted within the switch compartment 174 while the sealant 348 sets or cures. The sealant's exposure within the openings to ambient conditions tends to reduce the time in which it takes for the sealant 348 to cure. It is also noted that the preferred sealant 348 material is preferably a liquid epoxy and is electrically insulating. Those of ordinary skill in the art will appreciate, however, that other suitable sealants may be used. However, it is critical for sealants to have suitable viscosity to flow through the channels 188,190 and to the second downstream opening, here the circumferential opening 350, prior to setting or curing.
The preferred forms of the invention described above are to be used as illustration only, and should not be utilized in a limiting sense in interpreting the scope of the present invention. Obvious modifications to the exemplary embodiments, as hereinabove set forth, could be readily made by those skilled in the art without departing from the spirit of the present invention. Accordingly, the scope of the present invention will be limited only by the claims appended herein.
The inventors hereby state their intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of the present invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set forth in the following claims.
Number | Date | Country | Kind |
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201210135581.0 | May 2012 | CN | national |