Patent Application
20060042925
The present invention relates generally to electrical switch assemblies that are actuated by rotatable members, and, more particularly, to switches used in wiring harnesses, such as on appliances, including ignition systems for gas-fired appliances.
Electrical switches having rotatable actuators are used in a variety of applications. For example, it is known to use such switches in gas fueled cooking appliances. An electrical switch assembly is coupled to the rotatable valve stem of the gas valve, to control burner ignition circuitry. When the gas valve stem is rotated to place the valve in the open position and commence gas flow, the burner ignition electrical circuitry is energized to ignite the gas stream at the burner. In this way, stand-by pilot lights are not required, and gas ignition occurs simultaneously with opening the gas valve and commencing the flow of gas.
Fuel is not wasted keeping a pilot light burner. Considerable fuel savings can be experienced, particularly in appliances that are used infrequently, with prolonged periods of nonuse. Pilot-less ignition systems conserve fuel and thereby improve appliance efficiency.
U.S. Pat. No. 5,687,836 entitled “ELECTRICAL SWITCH ASSEMBLY ACTUATABLE BY A ROTATABLE MEMBER”, issued Nov. 18, 1997, describes one such electrical switch assembly having utility for gas fired appliances. The switch assembly disclosed therein can be connected in a parallel electrical circuit configuration. While providing many advantages, the switch assembly disclosed therein can be used only for a single circuit, and each switch function in each circuit requires a separate switch.
To improve appliance safety and enhance customer convenience, it is sometimes desirable to include multiple switching functions upon actuation or rotation of a single actuator. A variety of indicator lights to indicate status may be actuated with the primary function, or may be oppositely actuated. For example, it may be desirable to illuminate a “burner on” indicator together with actuation of the ignition circuitry when a gas valve is opened. An electric circuit to indicate ignition failure can be energized upon opening the gas valve, to be illuminated if ignition does not occur within a specific period of time. It may be desirable for various other safety and/or convenience features that are electrically operated to be actuated or de-actuated upon opening the gas valve.
As more and more individual switches for additional functions are combined with a single actuator, the actuator becomes unduly long and the switching mechanisms complex. Individual switches can be electrically connected, one to another, with only one controlled by the actuator and others electrically controlled therefrom. However the wiring harness becomes unduly large and complex, and requires significant space for installation. In appliances, it is desirable to minimize space requirements for controls and the like, to maximize area available for appliance functions, for example oven interior space, while minimizing overall appliance size.
There is a need in the art to provide a compact switching arrangement for multiple switching functions actuated by a single actuator to keep wiring harness assemblies compact.
The present invention provides a stackable switch assembly having a base switch housing and a cover, with one or more intermediate switch housings fitted between the base switch housing and the cover. The base switch housing and the intermediate switch housings each contain switches actuated by a single actuator extending therethrough.
In one aspect thereof, the present invention provides a multifunction switch assembly with a base switch housing having first switch disposed therein and at least one intermediate switch housing having an other switch disposed therein. The intermediate switch housing is adapted for mechanical engagement with the base switch housing. A cover is adapted for selective attachment to and engagement with the base switch housing and the intermediate switch housing. An actuator is disposed within the base switch housing and the intermediate switch housing for operating the first switch and the other switch.
In another aspect thereof, the present invention provides a rotatable switch assembly with a base housing having a base surface topography configured to hold switch components, to receive a rotatable actuator for operating the switch components and to receive an independent structure to cover the components. A cover has a cover surface topography configured to mechanically engage the base surface topography. An intermediate housing has on one side thereof a first surface topography substantially similar to the cover surface topography for mechanically engaging the base housing. An opposite side of the intermediate housing has a second surface topography substantially similar to the base surface topography for holding second switch components, for receiving the rotatable actuator for operating the second switch components and for mechanically engaging the cover. The first side of the intermediate housing is engaged with the base housing and the opposite side of the intermediate housing is engaged with the cover.
In still another aspect thereof, the present invention provides a switch assembly with a cover having a side with a first topography, and a base housing having a side with a second topography for holding switch components. The first and second topographies are configured to mechanically engage one with the other to secure the cover and the base to each other. An intermediate housing has a first surface with the first topography and an opposite surface with the second topography. The first surface of the intermediate housing is engaged with the base housing and the second surface of the intermediate housing is engaged with the cover.
An advantage of the present invention is providing a multi-function, multi-switch arrangement that is compact.
Another advantage of the present invention is providing multiple switches actuated by a single actuator.
Still another advantage of the present invention is providing multiple switches that require minimal space.
Still another advantage of the present invention is providing a multi-function switch assembly that can be expanded as required for additional switching functions.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.
Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use herein of “including”, “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof, as well as additional items and equivalents thereof.
Referring now more specifically to the drawings and to
Wiring harness 10 further includes a plurality of electrical conductors 16, 18, 20 and 22 connected to switch assemblies 12. As will be described further hereinafter, wiring harness 10 may have more or fewer conductors than the four conductors 16, 18, 20 and 22 shown in
With reference now to the exploded views of
Base housing 30 includes a general base surface topography 40 having a base peripheral skirt 42 and including various posts 44 and other shaped projections for holding a first switch 46 and for securing conductors 16 and 18 extending through base housing 30. Switch 46 includes a pair of resilient blades 48, 50 disposed in spaced relation within base housing 30. Blade 48 is electrically connected to conductor 16, and blade 50 is electrically connected to conductor 18. Deflection of blade 48 towards blade 50 sufficient to cause contact between blades 48 and 50 causes electrical connection between conductor 16 and conductor 18 through switch 46. A substantially central aperture 52 is provided through base housing 30. In the exemplary embodiment, base peripheral skirt 42 includes notches 54 for receiving conductors 16 and 18. Those skilled in the art will understand readily that the precise configuration of surface topography 40 will vary depending upon the specific type of switch 46 being used as well as the type and size of conductors 16 and 18 connected to switch 46.
Cover 32 includes a cover surface topography 60 having a cover peripheral skirt 62 and various projections 64 to aid in the positioning and retention of conductors 16, 18 and components of switch 46 held therebeneath. Peripheral skirt 62 of cover surface topography 60 includes notches 66 for conductors extended therethrough. Cover 32 is provided with a central aperture 68 substantially aligned with aperture 52 in the assembled switch assembly 12. Cover 32 and specifically surface topography 60 thereof, is configured and arranged to complement base housing 30 and specifically base surface topography 40 thereof. Cover surface topography 60 and base surface topography 40 engage one another to mechanically interlock and secure base 30 and cover 32 together. Conductors 16 and 18 and components of switch 46 are held securely in position after assembly.
For a single switch installation, two conductors 16 and 18 are passed through base housing 30 and blades 48 and 50 of switch 46 are electrically connected to conductors 16 and 18, respectively. Cover 32 is placed in interlocking mechanical engagement with base 30 through the cooperating surface topographies 40 and 60. Peripheral skirt 42 of base housing 30 fits substantially within peripheral skirt 62 of cover surface topography 60. Cooperating recesses 70, 72 can be provided in base 30 and cover 32, respectively, for proper orientation and alignment of base 30 and cover 32.
Intermediate housing 34 is provided between base housing 30 and cover 32 when multiple switching functions are to be performed. Intermediate housing 34 includes a first surface topography 80 thereof substantially similar to cover surface topography 60. Thus, first surface topography 80 includes a first surface peripheral skirt 82 and various projections 84 to aid in the positioning and retention of conductors 16, 18 and components of switch 46 held therebeneath. Peripheral skirt 82 of first surface topography 80 includes notches 86 for conductors extended therethrough. Intermediate hosing 34 is provided with a central aperture 88 substantially aligned with aperture 52 in the assembled switch assembly 12. Intermediate housing 34, and specifically first surface topography 80 thereof, is configured and arranged to complement base housing 30 and specifically base surface topography 40 thereof. First surface topography 80 and base surface topography 40 engage one another to mechanically interlock and secure base 30 and intermediate housing 34 together. Conductors 16 and 18 and components of switch 46 are held securely in position after assembly.
Intermediate housing 34 further includes a second surface topography 100 substantially similar to base housing surface topography 40. Thus, second surface topography 100 includes a second surface peripheral skirt 102 and including various posts 104 and other shaped projections for holding a second switch 106 and for securing conductors 20 and 22 extending through second intermediate housing 34. Second switch 106 includes a pair of resilient blades 108, 110 disposed in spaced relation within intermediate housing 34. Blade 108 is electrically connected to conductor 20, and blade 110 is electrically connected to conductor 22. Deflection of blade 108 towards blade 110 sufficient to cause contact between blades 108 and 110 causes electrical connection between conductor 20 and conductor 22 through switch 106. In the exemplary embodiment, second surface peripheral skirt 102 includes notches 114 for receiving conductors 20 and 22. Those skilled in the art will understand readily that the precise configuration of second surface topography 100 will vary depending upon the specific type of switch 106 being used as well as the type and size of conductors 20 and 22 connected to switch 106.
Intermediate housing 34 can be mechanically engaged with each base housing 30 and cover 32. Intermediate housing 34 is placed in interlocking mechanical engagement with base 30 through the cooperating surface topographies 40 and 80. Peripheral skirt 42 of base housing 30 fits substantially within peripheral skirt 82 of first surface topography 80 on intermediate housing 34. Intermediate housing 34 is placed in interlocking mechanical engagement with cover 32 through the cooperating surface topographies 60 and 100. Peripheral skirt 102 on second surface topography 100 of intermediate housing 30 fits substantially within peripheral skirt 62 of cover 60. Thus, when multiple switching functions are to be performed, first and second switches 46 and 106 are positioned one above another within a compact switch assembly 12, and conductors 16, 18, 20 and 22 for switches 46 and 106 are neatly arranged and secured. With a single intermediate housing 34 between base housing 30 and cover 32, two switching functions can be performed in a compact, integral structure.
It should be understood by those skilled in the art that two or more intermediate housings 34 may be positioned one interconnected with the other between base housing 30 and cover 32. Thus, if three switching functions are to be performed, two intermediate housings 34 are used. Adjacent intermediate housings 34 are placed in interlocking mechanical engagement with each other through the cooperating first and second surface topographies 80 and 100 of each Peripheral skirt 102 of second surface topography 100 on one intermediate housing 34 will fit substantially within peripheral skirt 82 of first surface topography 80 on an adjacent intermediate housing 34. The cooperating first and second surface topographies 80, 100 of adjacent intermediate housings 34 position and secure the components of additional switches and the conductors therefor in a similar manner as described above for first switch 46, second switch 106 and conductors 16, 18, 20 and 22.
A rotatable actuator 120 is provided through the aligned apertures of base 30, cover 32 and the one or more intermediate housings 34 provided in switch assembly 12. Actuator 120 can be, for example, an attachment to or an extension of the valve stem for gas valve 14 of a gas-fired kitchen range or the like, so that switches 46 and 106 are operated in combination with changes made in opening or closing gas valve 14. Switch assembly 12 also can be independent of any associated device such as gas valve 14, in which case a knob (not shown) or other structure is provided on actuator 120, for rotating actuator 120.
Actuator 120 is provided with a cam or cams 122 such that rotation of actuator 120 causes one or more cam 122 to operate first switch 46 and second switch 106. In the arrangement shown in
The present invention provides a compact, well-organized structure for wiring harness 10. Conductors 16, 18, 20 and 22 are aligned, positioned and held by switch assembly 12. Multiple switching functions can be provided in a single interconnected structure that is compact and requires minimal space, thereby facilitating the use -of an increased number electrically controlled features in an appliance or device with minimal space for the wiring harness components.
Variations and modifications of the foregoing are within the scope of the present invention It is understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention The claims are to be construed to include alternative embodiments to the extent permitted by the prior art.
Various features of the invention are set forth in the following claims.
