Patent Application
20060021861
This invention relates in general to vehicle control switch assemblies, and more specifically to control switches having an elastomeric pad.
A conventional switch bank (or array) is typically formed having a stacked (i.e., overlaid) structure. The switch bank is implemented to carry a low voltage DC signal. The switch bank is a group of normally open, single pole, single throw (NO, SP, ST) momentary contact device switches. The switch bank can include a graphic overlay having painted or printed on symbols that relate to numbers, vehicle functions, and the like depending on the application of the switch bank. For example, the overlay is disposed over an electrostatic discharge (ESD)/electromagnetic interference (EMI) shield. In another example, the overlay is disposed directly over a top membrane or elastomeric pad. The membrane has a number of contacts that align with the respective symbols when the switch bank is properly assembled.
The switch bank typically also includes a spacer disposed under the membrane. The spacer has holes that generally align with respective contacts in the membrane. A bottom membrane (or circuit board) includes circuit grids that generally align with the respective contacts such that a respective circuit is closed when a user sufficiently depresses the respective symbol. The switch bank can also include a subpanel (i.e., substrate, back cover, etc.) that generally provides physical support. The stackup or overlay of the respective symbol, contact, hole, and grid forms an individual switch in the switch bank.
The conventional switch bank has a number of deficiencies that include when the switch bank is manufactured, the layers (i.e., the overlay, the membrane, the spacer, the circuit board, and the sub-panel) can be difficult to align such that the respective symbols, holes, and circuits align properly, the switch bank is not lighted or backlit, the overlay and the symbols are not registered (i.e., the surface of the overlay is substantially smooth such that a user can not readily discern switch location and type by feel), and the switch bank does not provide tactile feedback feel to the user. Additionally, conventional switch banks, particularly rocker type switches with opposed contacts for first and second functions lack sufficient structural strength to prevent both contacts from being made when multiple forces are applied.
This invention relates to a vehicle control switch assembly for use with a printed circuit board. The switch assembly includes an elastomeric pad and a support member. The elastomeric pad has a contact pad for selective engagement with an electrical contact of the printed circuit board. The support member is molded together with the elastomeric pad.
The invention also relates to a vehicle control switch assembly. The assembly *includes a printed circuit board having an electrical contact, an elastomeric pad having a contact pad for selective engagement with the electrical contact of the printed circuit board, and a support member. The support member is positioned between the elastomeric pad and the printed circuit board to provide support for the elastomeric pad.
Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.
Vehicle interior passenger compartments are, in large measure, conventional in the art. The typical vehicle interior passenger compartment includes an instrument panel or dashboard. The instrument panel may include control mechanisms and switches for various components of the vehicle, such as, temperature and climate controls system, audio and video systems, windows, seat and mirror positioning mechanisms, and navigational systems. These controls may be positioned within the instrument panel, a lower console, doors, or any other suitable location within the interior of the vehicle. Alternatively, a second storage compartment (not shown) may be provided in the back seat area and can also have various controls (climate, windows, video gaming device controls, audio controls, headphone jacks, etc.) located thereon. An overhead console (not shown) can also be accessible from within the interior passenger compartment of the vehicle. The overhead console can contain various controls, such as a garage door opener, climate controls, etc. A rear overhead console can include a video display screen, climate controls, and other audio controls. Other vehicle controls that are user modifiable typically include seat positions for a vehicle driver seat (fore/aft position, seat height, seat back angle, etc.), audio and video presets, rearview and side view mirror positions, temperature control settings, seat belt height, steering wheel position, accelerator/brake pedal positions, interior light colors and intensity, airbag activation and sensitivity conditions, and many other settings. The majority of these components are typically controlled electronically by switches. It should be appreciated that the scope of this invention is not intended to be limited for use with the specific structure and controls for the vehicle interior passenger compartment described above, or with vehicle interior passenger compartments in general. On the contrary, as will become apparent below, this invention may be used in any desired environment for the purposes described below.
Referring now to the drawings, there is illustrated in
Illustrated in
The basic operation of the control switch apparatus 10 illustrated in accordance with the present invention are generally known in the art. Specifically, the switch 22 shown in
The elastomeric pad 34 may be a conventional elastomer pad suitable for use with switches, such as dome switches or membrane switches. The elastomeric pad 34 used herein may cover a portion of the circuit board 30 having the contacts 32a and 32b for the switch 22. It will be appreciated that the elastomeric pad 34 may cover an entire surface of the circuit board 30 or any portion thereof. At least a portion of the elastomeric pad 34 may transmit light therethrough or be adapted to be a light pipe, as will be described in greater detail below.
Positioned adjacent the elastomeric pad 34 is a support member 36. The support member 36 can be made of any suitable material such that the support member 36 is more rigid than the elastomeric pad 34. In a preferred embodiment, the support member 36 is a plastic member. It should be appreciated that the support member can also be a semi-rigid plastic member, a flexible metal member, or an elastomeric member. The support member 36 is more clearly illustrated in
The support member 36 is configured to provide feel and support for the elastomeric pad 34. When the elastomeric pad 34 is depressed by a user, the elastomeric pad 34 compresses and forces the first end 24 or second 26 of the support member 36 in the direction of the force applied by the user. The support member 36 also is used to provide lateral support for the switch 22 such that if the force applied by the user is in an axis not directly aligned with the end 24 and 26 of the switch 22, and therefore aligned with the respective contact pad 28a and 28b and corresponding contacts 32a and 32b, the support member 36 maintains the structural rigidity of the switch 22 and allows the indirect force applied by the user to act upon the support member 36 as if a direct force were applied to it. Thus, the application of force upon the switch, regardless of whether the applied force is direct or indirect, will cause the contact pad 32a or 32b that is at the end 24 and 26 of the switch 22 being depressed to travel into engagement with the corresponding contact 32a or 32b, according to the desires of the user. Additionally, the support member 36 will prevent both ends 24 and 26 of the switch 22 from being depressed simultaneously and prevent both contact pads 28a and 28b to engage the contacts 32a and 32b which could create a conflict of signal information. For example, if the rocker-type switch 22 is for locking and unlocking the vehicle doors, depressing both ends 24 and 26 of the switch 22 cannot, using the support member 36 according to the present invention, cause a locking mechanism to simultaneously lock and unlock the door or cause a conflicting signal to be sent to a control device.
In the preferred embodiment, the elastomeric pad 34 is molded to the support member 36 to secure the two components together. In the embodiment shown in
Illustrated in
Preferably, the switch 46 also includes a return mechanism (not shown) that automatically returns the switch 46 from one of the first and second positions to the neutral position after the switch 46 is released. The return mechanism would cooperate with a ball 54 and pivot 56 mechanism of the switch 46. When the switch 46 is pivoted up so that contact pad 62a engages contact 64a, a first pivot return would act against the switch 46 and causes the switch 46 to return to the neutral position when the switch 46 is released. When the switch 46 is pivoted down so that contact pad 62b engages contact 64b, a second pivot return would act against the switch 46 and cause the switch 46 to return to the neutral position when the switch 46 is released. An example of a switch 46 having this configuration is a window control switch in a vehicle. Typically, since a window can be opened or closed to varying degrees, the switch such as shown in
Any of a plurality of types of light sources can be used to illuminate the light pipe, including an incandescent bulb or a light-emitting diode (LED), a lens, and a reflector or collimating surface for directing the light toward the lens. Sometimes, more than one light source is used. In the preferred embodiment, an LED 74 is used with the switch 68. An LED 74 is a low voltage device that typically has a longer life than incandescent lamps. In addition, an LED 74 responds quickly to changes in current and produces a spectrum of light that is well defined and constrained. The support member/light pipe 72 has a light receiving end 80 and a light exiting end 82, and is continuous through the entirety of its cross section. It is preferred that the support member 72, is made of a material that has an index of refraction significantly higher than that of air. The LED 74 has one or more electrical connectors (not shown) and attaches the LED 74 to the printed circuit board 78 to form an electrical connection therewith. The light receiving end 80 of the support member 72 serves to introduce light into the support member 72. The light receiving end 80 can be the narrower, while the light exiting end 82 is the wider end of the support member. However, such a structure is not required. It is also preferred that the light receiving end 80 of the support member 72 includes a lens 76 for directing the light from the LED 74 through the support member 72. When the LED 74 is positioned at the focal point of a parabolic surface of the lens 76, some of the light strikes the parabolic surface. The light reflected from the parabolic surface travels in a trajectory generally parallel to the axis of revolution of the parabolic surface. Thus, the LED 74 produces a well-collimated light through the light pipe.
At least a portion of the elastomeric pad 70 may filter light therethrough. For example, a portion of the elastomeric pad 70 may transmit light therethrough and may be a translucent color, such that the light transferred therethrough is tinted to a desired color. It will be appreciated that at least a portion of the elastomeric pad 70 may be comprised of various layers of elastomer, each layer having various light transmission and/or filtering capabilities. The transmission or filtration of light through the elastomeric pad 70 may be desirable to illuminate an indicator or graphic on the switch 68 or on a portion of a housing disposed over a portion of the elastomeric pad 70. Alternatively, a graphic can be printed directly onto the elastomeric pad (such as a molded through graphic), or a translucent overlay having a graphic printed or etched thereon on can be positioned over a portion of the elastomeric pad. Regardless of the manner in which a graphic or indicator is made for the switch, the LED and light pipe act to illuminate (back-light) the graphic for ease of viewing by the user of the vehicle.
In accordance with the provisions of the patent statutes, the principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.
