WO1997044798A1 - Switch contact configuration - Google Patents

Abstract

Apparatus may include raised contacts with elongated mating surfaces which, when closed, provide an electrical contact area where the two elongated mating surfaces cross each other, to lower the electrical contact resistance and improve the contact reliability.

Description

Description SWITCH CONTACT CONFIGURATION

Technical Field This invention relates to switches, and more particularly to electrical contact switches

Background Art

As known, electrical contact switches may encounter contamination of their electrical contact surfaces from debris left over from the manufacturing process, or from deterioration of the switch itself Such contamination may cause an open circuit, i e switch failure, when the contacts attempt to close

The susceptibility of a switch to contamination failure depends in part on the contact configuration As an example, a butt contact configuration having substantially planar mating surfaces has been shown to be more susceptible to contamination failure than a modified configuration in which one of the flat surface contacts is replaced with a triangular, prism-like contact having an elongated mating surface, "knife edge" contact In this modified configuration the knife edge contact significantly reduces the likelihood of debris collecting on its surface Aside from contamination failure, there further exists the possibility of switch contact failure due to excessive power dissipation Electrical switch contacts have a finite resistance between their mating surfaces contacts when closed, resulting in a power dissipation across the contacts during electrical current conduction The magnitude of the power dissipation is directly proportional to the magnitude of the contact resistance, such that a lower magnitude resistance is preferred The contact resistance magnitude depends on the electrical conductivity of the contact material and the contact mating force per unit area (the magnitude of the closing force the switch contacts, divided by the magnitude of the contact mating area) The use of precious metals can reduce the contact resistance to some degree, however, precious metals are relatively expensive A higher actuation force could also reduce the contact resistance, however the magnitude of the actuation force may be limited by system constraints In fact, the switch designer must often design for the minimum and maximum actuation force which will be encountered

Disclosure of Invention An object of the present invention is to provide a reliable contact configuration for an electrical switch.

Another object of the present invention is to provide a contact configuration with a low electrical contact resistance

Still another object of the present invention is to provide a reliable electrical switch

According to the present invention a contact configuration comprises a first raised contact, having a first elongated mating surface projecting from the major surface of a first terminal platform, and further includes a second raised contact, having a second elongated mating surface, projecting from the major surface of a second terminal platform, for providing, in response to the presence and alternatively the absence of an applied force, which brings the two major surfaces toward each other, an electrical contact area where the two mating surfaces cross each other

In further accord with the present invention, a switch comprises a first raised contact, having a first elongated mating surface projecting from the major surface of a first terminal platform, and further includes a second raised contact, having a second elongated mating surface, projecting from the major surface of a second terminal platform, for providing, in response to the presence and alternatively the absence of an applied force, an electrical contact area where the two mating surfaces cross each other In still further accord with the present invention, a switch comprises a housing, and further includes a handle for receiving an applied force and for directing a force in a manner that is dependent upon the presence of the applied force, and further includes a first raised contact, having a first elongated mating surface projecting from the major surface of a first terminal platform, and further includes a second raised contact, having a second elongated mating surface, projecting from the major surface of a second terminal platform, for providing, in response to the presence and alternatively the absence of the force from the handle, which brings the two major surfaces toward each other, an electrical contact area where the two mating surfaces cross each other.

Brief Description of the Drawings FIG. 1 is a perspective illustration of an electrical rocker switch in which the contact configuration of the present invention may be used;

FIG. 2 is a partially cut away view of the switch of FIG. 1; FIG. 3 is a perspective illustration of the contact configuration of the present invention as used in the switch of FIGS. 1 and 2 shown in an open state, FIG. 4 is a perspective illustration of the contact configuration of FIG. 3, shown in a closed state;

FIG 5 is a cross section of one of the contact configuration of FIGS. 1, 3; FIG 6A is a perspective illustration of an alternative embodiment of the contact configuration of the present invention; FIG. 6B is a perspective illustration of a second alternative embodiment of the contact configuration of the present invention,

FIG. 6C is a perspective illustration of a third alternative embodiment of the contact configuration of the present invention;

FIG 6D is a perspective illustration of a fourth alternative embodiment of the contact configuration of the present invention,

FIG. 6E is a perspective illustration of a fifth alternative embodiment of the contact configuration of the present invention; and

FIG 7 is a schematic illustration of an automobile door lock assembly in which the switch illustrated in FIGS. 1-2 may be used.

Best Mode for Carrying out the Invention

The contact configuration of the present invention is disclosed with respect to a best mode embodiment for use in an electrical rocker switch of the type illustrated in FIG 1. As should be understood by those skilled in the art, the Drawings are illustrative only and are not intended to portray exact structural dimensions. Referring to FIG 1, a single pole, double throw, electrical rocker switch 30, for use in an automobile door lock assembly, includes a housing 32, a cover 34, and a handle 36 The housing provides the mechanical support for the switch 30, and in conjunction with the cover 34 that fits over the housing, provides environmental protection for the internal portions of the switch The handle 36 is attached to the housing 32 at pivot point 38 which allows the handle to "rock" from side to side with applied force from an operator

In the best mode embodiment, the housing 32, cover 34, and handle 36 comprise individually molded pieces, preferably plastic, however, as may be understood by those skilled in the art, the materials and fabrication techniques for this assembly are a matter of design choice, and may vary with the intended switch application The housing further includes an electrical connector interface 40, through which the switch 30 is electrically connected to the rest of the door lock assembly circuit (shown in FIG 7) Referring now to FIG 2, in a perspective, partially cut away illustration of the rocker switch 30 of FIG. 1, the handle has a hollowed out portion with an end wall 42 and side walls 44 A coil spring 46 is positioned with one end against the end wall 42, and the other end inserted into a plunger 48 The plunger 48 has a substantially cylindrical shape with one open end 50 that receives the spring 46, and one closed rounded end 52 The open end 50 of the plunger 48 rides inside side walls 44 of the hollowed out portion of the handle 36, while the closed round end 52 is positioned on a contactor 54

The contactor 54 has a pivot portion 56 with a contoured track section 58 that receives the plunger 48 The track section 58 is comprised of two generally curved portions 60, 62 which together provide a substantially arc-like contour In the absence of an applied force on the handle 36, the plunger 48 rests in the middle of the track section 58, which balances the contactor 54 about its pivot portion 56 The contactor 54 is shown in this balanced position The contactor 54 further comprises a first terminal end 64 and a second terminal end 66 The first and second terminal ends 64, 66 are electrically connected and serve as the common pole in the single pole double throw switch The two terminal ends 64, 66 are electrically connected to the electrical connector interface 40 The first terminal end 64 comprises a platform 68, having a major surface 69 (more clearly evident in FIG 3), and a raised contact 70 (viewed in FIG 2 from its underside) projecting from and supported by the major surface 69 of the platform The second terminal end 66 is substantially similar to the first terminal end 64, and also comprises a platform 72, having a major surface 73, and a raised contact 74 projecting from the major surface 73 of the platform 72

In the best mode embodiment, the contactor, including the platforms 68, 72 of the terminal ends 64, 66, is electrically conductive and preferably comprises brass C26000, which is suitably stiff and sufficiently sturdy to withstand the force applied by the plunger However, those skilled in the art will recognize that various other materials, which may include copper, may be used as permitted by the particular application

The first and second terminal ends 64, 66 are substantially in register with a first stationary terminal 76 and a second stationary terminal 78, respectively The two stationary terminals are each electrically connected to the electrical connector interface 40 The first stationary terminal 76 comprises a platform 80 and a raised contact 82

The platform 80 has a major surface 81, which is spaced apart from and faces toward the major surface 69 of the first terminal end 64 The platform is supported in position by two L-shaped flanges 84, which are adapted to facilitate the insert molding of the first stationary terminal 76 into the switch The raised contact 82 projects from the major surface 81 of the platform 80 In the best mode embodiment, the platform 80 and raised contact 82 are each electrically conductive, and the platform 80 is connected through one of its flanges 84 to the electrical connector interface 40 The raised contact 82 is thereby electrically connected to the electrical connector interface 40, however as described below, other suitable configurations for connecting the raised contact to the connector interface may also be used

The second stationary terminal is substantially similar to the first stationary terminal and also comprises a platform 86, having a major surface 87 and flanges 90, and a raised contact 88 The platform 86 and raised contact 88 are each electrically conductive and the raised contact 88 is electrically connected, through one of the flanges 90 of the platform 86, to the electrical connector interface 40

In the best mode embodiment, the platforms and stationary terminals preferably comprise nickel plated copper-C/./006> However, those skilled in the art will recognize that various other materials, including other copper alloys, could also be used for the base material as permitted by the particular application Such other materials may include brass plated with nickel or equivalent The plating materials for the stationary terminal are also dependent on the current load For example, for current loads of between about 10 milli amperes (amps) and about 5 amps, nickel is a suitable plating In applications below about 10 milli amps, gold plating, silver plating or palladium nickel plating may be more appropriate If the raised contacts 82, 88 are formed out of the platform of the stationary terminals 76, 78, as in the best mode embodiment, the appropriate materials for the platforms 80, 86 of the stationary terminals will also depend on the number of switch actuation cycles required for the application The electrical connector interface 40 provides the means for electrically connecting the switch 30 to the rest of the door lock assembly circuit (shown in FIG 7) In the best mode embodiment, the electrical connector interface 40 has a first conductor 91A electrically connected to the first stationary terminal 76, a second conductor 9 IB electrically connected to the first and second contactor terminals 64, 66 by way of the contactor 54, and a third conductor 91 C electrically connected to the second stationary terminal 78 However, those skilled in the art should recognize that the electrical connector interface 40 may be suitably adapted for any switch application and, alternatively, may not be required when the electrical circuit opened and closed by the switch is located within the same housing as the switch The electrical interface connector 40 receives a mating plug 92 which electrically connects the switch 30 to the door lock assembly circuit (shown in FIG 7) The mating plug 92 has a first conductor 93A which electrically connects to the first conductor 91A in the electrical connector interface 40, a second conductor 93B which electrically connects to the second conductor 91B in the electrical connector interface

40, and a third conductor 93C which electrically connects to the third conductor 91C in the electrical connector interface 40

In the operation of the switch 30, the contactor 54 pivots between three positions In the absence of an applied force on the handle 36, the plunger 48 rests in the middle of the track section 58, which balances the contactor 54 at its pivot portion

56, creating an open circuit between each of the contactor terminal ends and the associated stationary terminals When the operator pivots the handle 36, the plunger 48 slides from the middle of the track section 58 onto a direction related one of the curved portions 60, 62 As the plunger travels along the curved portion the contactor rocks about its pivot 56 until electrical contact is made between one of its terminal ends 64, 66 and the associated one of the stationary terminals 76, 78 When the operator force is removed the spring 46 mechanically biases the plunger 48 back to the balanced, or open position

In the best mode embodiment, the actuation force required by the operator to pivot, or rock, the handle is in the range of from about 500 grams to about 1500 grams This actuation force provides the required "feel", reflecting the effort that the switch requires from the operator to rock the handle However, those skilled in the art know that the required actuation force may be suitably changed, by modification of various components of the switch 30, without affecting other aspects of the switch 30 In the best mode embodiment, the platforms 68, 72, 80, 86 of the terminal ends

64, 66 and stationary terminals 76, 78 have substantially planar form, i.e substantially flat plates, and are spaced apart and substantially in register and parallel However, other suitably oriented structures comprising suitable materials which provide a pair of suitable major surfaces for locating the pairs of raised contacts, and which allow the raised contacts to be brought into contact may also be used When the contacts are closed, the major surfaces of the platforms preferably face each other so that the major surfaces better support the raised contacts

The point of novelty of the present switch is the contact configuration of the contactor terminal end 64, 66 and the associated stationary terminal end 76, 78. FIG. 3 illustrates a broken away portion of the stationary terminal 76 and its associated terminal end 64 of the contactor.

Referring now to FIG 3, the raised contacts 70, 82 of the first terminal end 64 and first stationary terminal 76, each comprise a base 94, 96 and a mating surface 98, 100, respectively The sizes and shapes of the raised contacts 70, 82 are such that, when the contact configuration is in the closed position, they electrically contact each other at their mating surfaces 98, 100 In the best mode embodiment, the raised contacts 70, 82 and their mating surfaces 98, 100 are each elongated However, as those skilled in the art should recognize in light of the description below, only the mating surfaces 98, 100 need be elongated, and therefore, the raised contacts 70, 82 may have any size and shape that provides such mating surfaces

In the best mode embodiment, the two raised contacts 70, 82 each have a substantially triangular prism-like shape and the mating surfaces 98, 100 are positioned along the ridge, or crest, of the raised contacts 70, 82 This helps to keep debris from collecting on the mating surfaces 98, 100 In the best mode embodiment, the raised contacts 70, 82 each have an overall length 102, 104 and width 106, 108, where the overall length is defined herein as the larger of two dimensions The magnitudes of the overall lengths 102, 104 are preferably in the range of from 0.125 inches to 0.50 inches, however, any suitable overall lengths may be used. The best mode embodiment improves the reliability and aids manufacture of the contact configuration However, so long as the raised contacts provide suitable mating surfaces for the application, the raised contact need not have such overall size, shape or distinguishable length and width.

The mating surfaces 98, 100 themselves have a length 114, 116, a width 118, 120 (see also FIG 5) and a longitudinal axis 122, 124 running in the direction of its length 114, 116 In the best mode embodiment, the length 114, 116 of each mating surface 98, 100 is substantially equal in magnitude and parallel to the overall length 102, 104 of its raised contact 70, 82 In contrast, the width 118, 120 of each mating surface 98, 100 is much less than that of its raised contact 70, 82

The positioning of the raised contacts 70, 82 on the major surfaces 69, 81 of the platforms 68, 80 is such that their mating surfaces 98, 100 are cross positioned, preferably around their midsections, when the contact configuration is in the closed position For purposes of the discussion herein, the cross positioning of the contacts means that they are not parallel, but instead are relatively positioned such that each extends across the other in the closed position More specifically, the raised contacts should be positioned such that a plurality of angles formed by the crossing mating surfaces 98, 100 are in the range of from about 30 degrees to about 150 degrees, which reduces the mating area between the raised contacts 70, 82, thereby increasing the mating force per unit area and lowering the contact resistance This range also allows the contact configuration to accommodate mechanical tolerances/play and may also reduce the susceptibility to contamination failure Positioning with crossing angles as extreme as 10 degrees and 770 degrees may also work depending upon the application The preferred range for the crossing angles is in the range of from about 60 degrees to about 120 degrees, and more preferably from about 80 degrees to about 100 degrees, or substantially perpendicular, which increasingly further reduces the contact resistance, further accommodates greater mechanical tolerances/play, and may further reduce the susceptibility to contamination failure

To insure that the mating surfaces 98, 100 cross, the length 114, 116 of each mating surface 98, 100 is greater than the width 118, 120 of the other mating surface In the best mode embodiment, the length 114, 116 of each mating surface 98, 100 is at least about 5 times greater than its width 118, 120, and preferably is at least about 10 times to 100 times greater than the width Furthermore, in the best mode embodiment, the lengths 114, 116 of the mating surfaces 89, 100 have about the same magnitude as each other. However, as should be obvious to those skilled in the art, the mating surfaces 98, 100 may have any suitable lengths 114, 116 and widths 118, 120 which meet the application requirements, e.g current, contact resistance, reliability, manufacturability, and accommodation of mechanical tolerances/play

In the best mode embodiment, the raised contacts 70, 82 are further positioned such that the length of the raised contact 82 is substantially parallel to the length of the contactor 54, and the length of the raised contact 70 is substantially perpendicular to the length of the contactor 54 This positioning further improves the ability of the contact configuration to accommodate manufacturing tolerances and mechanical play, and aids manufacture of the contact configuration, however, any other suitable positioning of the raised contacts 70, 82 relative to the contactor 54 may also be used It should be recognized that although the raised contacts 70, 82 appear to have sharp edges at their mating surfaces 98, 100, in the best mode embodiment, they have a radius as described hereinbelow with respect to FIG 5. Referring now to FIG 5, in a simplified cross section of the raised contact 82 on the first stationary terminal 76, the raised contact 82 has a radius 126 which provides a curved surface 128 The mating surface 100 with its width 120, comprises a portion of the curved surface 128

The choice of whether to incorporate a radius 126, and if so, the magnitude of the radius 126 should be made in consideration of the application requirements The radius 126 should be chosen such the mating surfaces 98, 100 provide the required contact resistance and current handling capability Preferably, the radius 126 is such that debris does not collect on the mating surfaces 98, 100 and thereby cause failure

Furthermore, the radius 126 should allow the mating surfaces 98, 100 to accommodate the contact mating force and the switch actuation cycle requirement without significant deformation, since mating surface deformation could increase susceptibility to contamination failure and/or increase the contact resistance. In the best mode embodiment, the radius 126 at the peak of the raised contact

82 is preferably in the range of from about 0.3 milli meters (mm) to about 1.0 mm This range is chosen to accommodate a switch current magnitude of from about 10 milli amps to about 5 amps, a handle actuation force of from 500 grams to 1500 grams, 100,000 switch actuation cycles However, any other suitable radius may also be used Referring again to FIG 3, the raised contacts 70, 82 have a thickness 130, 132 defined herein as the displacement from the major surface 69, 81 of the platform 68, 80 to the mating surface 98, 100 of the raised contact The raised contacts 70, 82 should have sufficient thickness to allow them to electrically contact each other without obstruction when closed In the best mode embodiment, the thickness 130, 132 of each of the raised contacts 70, 82 is substantially uniform throughout the majority of its length 102, 104., having a magnitude preferably in the range of from 0.030 inches to 0.060 inches Given this thickness, the distance, or gap, between the mating surfaces 98, 100, when the contact configuration is in the open state, is in the range of from 0.020 inches to 0.035 inches However, any suitable thickness 130, 132 and gap known to those skilled in the art may be used. The ratio of the thickness 130, 132 of the raised contact 70, 82 to the width 106, 108 of the raised contact is preferably in the range of from 1:1 to 1:5 This range provides the desired sturdiness and stability to the raised contact 70, 82, however, any other suitable shapes may also be used In the best mode embodiment, the raised contacts 70, 82 are formed out of the platforms 68, 80 of the first terminal end 64 and the first stationary end 76 by stamping, however, any other suitable method for fabricating the raised contacts may also be used, including, but not limited to, manufacturing the raised contacts 70, 82 separately and welding them onto the major surfaces 69, 81 of the platforms 68, 80 Similarly, the stamping may be by any one of suitable means known to those skilled in the art Further, although the raised contacts 70, 82 in the best mode embodiment are comprised of the same material as the first terminal end 64 and first stationary terminal 76 respectively, in situations where the raised contacts are not formed out of the terminals, the raised contacts may comprise the same or different material than that of the terminals (see FIGS 6A-6E)

Referring now to FIG 4, when the operator pivots the handle 36 (FIGS 1 , 2) the force of the plunger 48 on the curved portion 60 of the track 58 causes the contactor 54 to rock until the mating surface 98 of the raised contact 70 on the contactor terminal end 64 makes contact with the mating surface 100 of the raised contact 82 on the associated stationary terminal 76 This contact configuration increases the reliability of the switch 30 by reducing the susceptibility to contamination failure while still accommodating manufacturing tolerances and mechanical play The reliability is further improved by reducing the mating area between the raised contacts 70, 82, which increases the mating force per unit area and lowers the contact resistance between the raised contacts 70, 82

Referring now to FIG 6 A, in another embodiment of the contact configuration of the present invention, the raised contact 82 of the first stationary terminal 76 has an alternate geometry and alternate method of manufacture The raised contact 82 still has a base 96 and an elongated mating surface 100 which crosses the mating surface 98 (see FIG 30) of the other raised contact 70 when the contacts are closed However, in this embodiment, the shape of the raised contact 82 is substantially cylindrical-like rather than substantially triangular prism-like The substantially cylindrical-like shape of the raised contact 82 is generally representative of that of a cylindrical wire conductor The elongated mating surface 100 is located along the crest of the raised contact 82

As shown, the raised contact 82 has been manufactured separately from the platform 80 The raised contact 82 is attached to the major surface 81 of the platform 80 by welding at the base 96 of the raised contact 82 However, any other suitable method known to those skilled in the art may also be used to attach the raised contact 82 to the platform 80 Such manufacture of the raised contact 82 may be appropriate where the desired shapes for the raised contacts and mating surfaces can be manufactured separately and attached to the platform more readily than they can be formed from the platform

It should be recognized that although the raised contact 82 appears to have a radius at its peak which is larger than that preferred in the best mode embodiment, the raised contact 82 may actually have a larger or smaller radius at its peak than preferred in the best mode embodiment As explained hereinabove, the shapes and sizes which are suitable for the raised contacts have various application specific considerations Those skilled in the art will recognize which shapes and sizes are appropriate for each application Referring now to FIG 6B, yet another embodiment of the present invention comprises two substantially cylindrical raised contacts 70, 82 which are manufactured and shaped comparably to the raised contact 82 of the first stationary terminal 76 in FIG 6 A The mating surface 98 on the raised contact 70 of the first terminal end 64 may be assumed to be identical to the mating surface 100 on the raised contact 82 of the first stationary platform 76 As described above, the mating surfaces 98, 100 are oriented so as to cross positionally when the contacts are closed

Such separate manufacture and welding of the raised contacts 70, 82 may be appropriate in an application that requires precious metal raised contacts For example, in situations where the contact configuration must handle current magnitudes in the range between 5 amps and 30 amps, then raised contacts comprising solid silver tin oxide, may be desired

Referring now to FIG 6C, still another embodiment of the contact configuration of the present invention comprises a pair of raised contacts 70, 82 which have a curvilinear shape rather than the substantially triangular prism-like shape of the raised contacts in FIGS 2-5 The mating surface 98 on the raised contact 70 of the first terminal end 64 may be assumed to be substantially identical to the mating surface 100 on the raised contact 82 of the first stationary platform 76 The mating surfaces 98, 100 are elongated and oriented so as to cross positionally when the raised contacts 70, 82 are closed As shown, the raised contacts 70, 82 have been manufactured separately from the platforms 68, 80, and later attached Those skilled in the art will know of suitable means for attachment of the raised contacts 70, 82 Alternatively, the raised contacts similar to those shown might also have been manufactured by forming the raised 70, 82 contacts out of the platforms 68, 80 Referring now to FIG 6D, in yet still another embodiment raised contacts with substantially planar, or flat, mating surfaces 98, 100 may be used if the application allows The mating surface 98 on the raised contact 70 of the first terminal end 64 may be assumed to be substantially identical to the mating surface 100 on the raised contact 82 of the first stationary platform 76. The mating surfaces 98, 100 are still elongated and still cross positionally when the raised contacts 70, 82 are closed This contact configuration can still produce a smaller contact mating area, which concentrates the gram force and lowers the contact resistance between the two raised contacts However, because the raised contacts 70, 82 have substantially flat mating surfaces 98, 100, they may not be as effective at reducing the susceptibility of the switch to contamination failure as the raised contacts 70, 82 in FIGS 2-5, 6A-6C

Referring now to FIG. 6E, yet another embodiment of the contact configuration of the present invention has the length of each mating surface 98, 100 oriented generally perpendicular rather than generally parallel to the length 102, 104 of its raised contact 70, 82 The mating surface 98 on the raised contact 70 of the first terminal end 64 may be assumed to be substantially identical to the mating surface 100 on the raised contact 82 of the first stationary platform 76 The mating surfaces 98, 100 are still elongated, and are still oriented so as to cross positionally when the raised contacts 70, 82 are closed

Referring now to FIG. 7, a figurative, schematic illustration of an automobile door lock assembly circuit 136 shows one application for the electrical rocker switch

30 In the door lock assembly circuit 136, a battery 138 has a first terminal 140 connected to ground 142, and a second terminal 144 which provides a 12 volt signal on line 146 The 12 volt signal is presented to a first relay 148, having a pair of normally open contacts A first contact 150 receives the 12 volt signal from the battery 138, and a second contact 152 is electrically connected to first terminals 156 on a plurality of motors 158 A different motor is used to control each of the door locks One door lock is provided for each of the doors of the automobile (not shown) The first relay 148 also has a coil 160 with a pair of leads, a first 162 receiving the 12 volt signal from the battery 138, and a second connected to the first stationary terminal 76 of the switch 30 by way of the first conductors 93A, 91A in the mating plug 92 and electrical interface connector 40

The contactor 54 of the switch 30 is connected to ground 142 by way of the second conductors 91 B, 93B in the electrical interface connector 40 and the mating plug 92 The second stationary terminal 78 of the switch 30 is electrically connected through the third conductors 91C, 93C in the electrical interface connector 40 and mating plug 92 to a first lead 166 of a coil 168 in a second relay 170 A second lead 172 of the coil 168 receives the 12 volt signal from the battery 138 The second relay 170 also has a pair of normally open contacts, a first 174 of which receives the 12 volt signal from the battery 138, and a second 176 which is electrically connected to second terminals 180 on the plurality of motors 158 The plurality of motors 158 have third terminals 182 which are connected to ground 142

When the operator pivots the handle 36 (FIGS 1, 2) such that the contactor 54 electrically contacts the first stationary terminal 76, the ground signal is received by the first stationary terminal 76 and thereby provided to the first relay 148 coil 160 This initiates closure of the first relay 148 contacts 150, 152 The closed contacts 150, 152 provide the 12 volt signal to the first terminals 156 of the motors 158, which then provide the motion to engage the door locks

When the operator pivots the handle 36 (FIGS 1, 2) such that the contactor 54 electrically contacts the second stationary terminal 78, the ground signal is received by the second stationary terminal 78 and thereby provided to the second relay 170 coil

168 This initiates closure of the second relay 170 contacts 174, 176 The closed contacts 174, 176 provide the 12 volt signal to the second terminals 180 of the motors 158, which then provide the motion to disengage the door locks

In the application above, the magnitude of the switch current is in the range of from 400 milli amps to 2 amps, although the switch 30 described in the best mode embodiment has the capability to reliably handle currents having magnitudes in the range of from about 10 milli amps to about 5 amps. Thus, if the current required by the motors 158 is not above 5 amps, the relays 148, 170 may be deleted and the switch 30 may be used to directly switch the 12 volt signal from the battery 138 to the motors 158

It should be obvious to those of ordinary skill in the art that the contact configuration of the present invention may be adapted to reliably handle higher and lower current magnitudes than that of the best mode embodiment. In each instance, those skilled in the art will recognize the appropriate characteristics for the contact configuration For example, where higher current magnitudes are encountered, raised contacts comprising precious metals may be desired, as suggested hereinabove with respect to FIG 6B Where lower current magnitudes are encountered, precious metal plating may be desired, as suggested hereinabove with respect to FIG. 2

Although the best mode embodiment illustrates the contact configuration of the present invention in a manually operated rocker switch, those skilled in the art will recognize that the contact configuration of the present invention may be used in any type of electrical switch having any manner of actuation Thus, it will be obvious to those skilled in the art that the present invention may be used in a switch employing other types of manual actuation, including but not limited to, push button switches, and switches with sliding handles The present invention may also be used in switches not having discrete actuation mechanisms, such as those integrated into tactile keypads

Furthermore, the present invention may also be used in switches which do not use manual actuation, such as those employing electromechanical actuation, e g relays and solenoids Pneumatic and hydraulic actuation, among others, may also be used It will be obvious to those skilled in the art that the present invention may be used regardless of whether the switch contacts are open/closed directly, or whether linkage is used to translate the actuation force to the contacts Thus, the present invention may also be used in switches employing mechanical, pneumatic, or hydraulic linkage, among others Further, although the best mode embodiment illustrates the contact configuration of the present invention in a single pole double throw switch having a two terminal movable contactor and two stationary terminals, those skilled in the art will recognize that the contact configuration of the present invention may be used in any type of electrical switch regardless of the number and configuration of the poles and terminal configuration For example if the two contactor terminal ends 64, 66 are not electrically connected to each other, and if each is connected to its own conductor in the electrical connector interface 40 (FIGS 1, 2), then the switch 30 would be a double pole double throw switch Still further, although the best mode embodiment of the switch 30 provides an open circuit between the contactor terminal ends 64, 66 and its associated one of the stationary terminals 76, 78 in the absence of an applied force, and a closed circuit in the presence of the applied force, it should be understood that alternative configurations may also be used including one that provides a closed circuit in the absence of an applied force and an open circuit in the presence of the applied force

While the particular invention has been described with reference to illustrative embodiments, this description is not meant to be construed in a limiting sense. It is understood that, various modifications of the illustrative embodiments, as well as additional embodiments of the invention, will be apparent to persons skilled in the art upon reference to this description without departing from the spirit of the invention, as recited in the claims appended hereto. Thus, upon understanding the present invention, one of ordinary skill in the art could employ the present invention in a variety of contact or switch applications Those skilled in the art will know of the forms which are suitable for each application It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention What is claimed is

Claims

Claims

1 Apparatus, for use in a switch of the type which alternately opens and closes an electrical signal path between first and second conductors thereof in response to the alternate absence and presence of an applied force, comprising first and second platforms, each having a major surface thereon, said platforms being relatively positioned to provide said major surfaces in substantially spaced apart registration, said platforms further being movable with respect to each other to permit said major surfaces to be placed in alternately further and closer proximity to each other in the alternate absence and presence of the applied force, a first raised contact, disposed on said first platform major surface, said first raised contact projecting upward from said first platform major surface and providing a first elongated mating surface having a length and a width, said first raised contact further being adapted for electrical connection to the first conductor, and a second raised contact, disposed on said second platform major surface, said second raised contact projecting upward from said second platform major surface and providing a second elongated mating surface having a length and a width, said second raised contact further being adapted for electrical connection to the second conductor, the length of each of said first and said second elongated mating surfaces being greater than the width of the other, said second raised contact being positioned on said second platform major surface so as to cause said first and second elongated mating surfaces to cross positionally and electrically contact each other upon said placement of said first and second platforms in said closer proximity to each other

2 The apparatus of claim 1 wherein said first and said second raised contacts are formed out of said first and said second platforms 3 The apparatus of claim 1 wherein said first and said second raised contacts are manufactured separately from and later attached to said first and said second platforms

4 The apparatus of claim 1 wherein said first raised contact is elongated having a length, and said length of said first raised contact is parallel to said length of said first elongated mating surface, and said second raised contact is elongated having a length, and said length of said second raised contact is parallel to said length of said second elongated mating surface

5 The apparatus of claim 1 wherein said first raised contact has a crest having a radius, and said second raised contact has a crest having a radius

6 The apparatus of claim 5 wherein said first and said second raised contact radii are in the range of from about 0.3 milli meters to about / 0 milli meters

7 The apparatus of claim 1 wherein said first and said second raised contacts have a substantially a triangular prism-like shape

8 The apparatus of claim 1 wherein said first and said second raised contacts have a substantially cylindrical-like shape

9 The apparatus of claim 1 wherein said first and said second raised contacts each have a width and a thickness, and for each of said first and said second raised contacts, the ratio of its thickness to its width is in the range of from about 1:1 to about 1:5 10 The apparatus of claim 1 wherein said first and said second raised contacts each compπses at least one of nickel plated copper and brass

11 The apparatus of claim 4 wherein said first raised contact has a crest having a radius and said second raised contact has a crest having a radius, the radii having magnitudes in the range of from about 0 3 milli meters to about / 0 milli meters, said first and said second raised contacts each have a width and a thickness, and for each of said first and said second raised contacts, the ratio of its thickness to its width is in the range of from about / / to about 1 5, and a plurality of angles at said positional crossing of said first and said second elongated mating surfaces are in the range of from about 30 degrees to about 150 degrees

12 A switch for alternately opening and closing an electrical signal path between a first and second conductor in an electrical circuit thereof in response to the alternate absence and presence of an applied force, comprising an electrical interface having a first conductor for electrical connection to the first conductor in the electrical circuit and a second conductor for electrical connection to the second conductor in the electrical circuit, first and second platforms, each having a major surface thereon, said platforms being relatively positioned to provide said major surfaces in substantially spaced apart registration, said platforms further being movable with respect to each other to permit said major surfaces to be placed in alternately further and closer proximity to each other in the alternate absence and presence of the applied force, a first raised contact, disposed on said first platform major surface, said first contact projecting upward from said first platform major surface and providing a first elongated mating surface having a length and a width, said first contact further being adapted for electrical connection to said first conductor of said electrical interface, and a second raised contact, disposed on said second platform major surface, said second contact projecting upward from said second platform major surface and providing a second elongated mating surface having a length and a width, said second contact further being adapted for electrical connection to said second conductor of said electrical interface, the length of each of said first and said second elongated mating surfaces being greater than the width of the other, said second raised contact being positioned on said second platform major surface so as to cause said first and second elongated mating surfaces to cross positionally and electrically contact each other upon said placement of said first and second platforms in said closer proximity to each other

13 The apparatus of claim 12 wherein said first and said second raised contacts are formed out of said first and said second platforms.

14 The apparatus of claim 12 wherein. said first and said second raised contacts are manufactured separately from and later attached to said first and said second platforms

15 The apparatus of claim 12 wherein said first raised contact is elongated having a length, and said length of said first raised contact is substantially parallel to said length of said first elongated mating surface, and said second raised contact is elongated having a length, and said length of said second raised contact is substantially parallel to said length of said second elongated mating surface 16 The apparatus of claim 12 wherein said first raised contact has a crest having a radius, and said second raised contact has a crest having a radius

17 The apparatus of claim 16 wherein said first and said second raised contact radii are in the range of from about 0.3 milli meters to about 1.0 milli meters

18 The apparatus of claim 12 wherein said first and said second raised contacts have a substantially a triangular prism-like shape

19 The apparatus of claim 12 wherein said first and said second raised contacts have a substantially cylindrical-like shape

20 The apparatus of claim 12 wherein said first and said second raised contacts each have a width and a thickness, and for each of said first and said second raised contacts, the ratio of its thickness to its width is in the range of from about 1:1 to about 1:5

21 The apparatus of claim 12 wherein said first and said second raised contacts each comprises at least one of nickel plated copper and brass

22 The apparatus of claim 15 wherein said first raised contact has a crest having a radius and said second raised contact has a crest having a radius, the radii having magnitudes in the range of from about 0.3 milli meters to about 1.0 milli meters, said first and said second raised contacts each have a width and a thickness, and for each of said first and said second raised contacts, the ratio of its thickness to its width is in the range of from about 1:1 to about 1:5, and a plurality of angles at said positional crossing of said first and said second elongated mating surfaces are in the range of from about 30 degrees to about 150 degrees.

23 A switch for alternately opening and closing an electrical signal path between a first and second conductor in an electrical circuit thereof in response to the alternate absence and presence of an applied force, comprising. a housing providing an enclosure; a handle responsive to the applied force, said handle attached to said housing and having an exterior portion residing outside of said housing enclosure for receiving the applied force, and an interior portion extending into said housing enclosure for directing a force in a manner that is dependent upon said position of said exterior portion, an electrical interface having a first conductor for electrical connection to the first conductor in the electrical circuit and a second conductor for electrical connection to the second conductor in the electrical circuit, first and second platforms, each having a major surface thereon, said platforms being relatively positioned to provide said major surfaces in substantially spaced apart registration, said platforms further being movable with respect to each other to permit said major surfaces to be placed in alternately further and closer proximity to each other in response to said force from said handle; a first raised contact, disposed on said first platform major surface, said first contact projecting upward from said first platform major surface and providing a first elongated mating surface having a length and a width, said first contact further being adapted for electrical connection to the first conductor of the electrical interface; and a second raised contact, disposed on said second platform major surface, said second contact projecting upward from said second platform major surface and providing a second elongated mating surface having a length and a width, said second contact further being adapted for electrical connection to the second conductor of the electrical interface, the length of each of said first and said second elongated mating surfaces being greater than the width of the other, said second raised contact being positioned on said second platform major surface so as to cause said first and second elongated mating surfaces to cross positionally and electrically contact each other upon said placement of said first and second platforms in said closer proximity to each other.

24 The apparatus of claim 23 wherein said first and said second raised contacts are formed out of said first and said second platforms

25 The apparatus of claim 23 wherein said first and said second raised contacts are manufactured separately from and later attached to said first and said second platforms

26 The apparatus of claim 23 wherein said first raised contact is elongated having a length, and said length of said first raised contact is substantially parallel to said length of said first elongated mating surface, and said second raised contact is elongated having a length, and said length of said second raised contact is substantially parallel to said length of said second elongated mating surface

27 The apparatus of claim 23 wherein said first raised contact has a crest having a radius; and said second raised contact has a crest having a radius

28 The apparatus of claim 16 wherein said first and said second raised contact radii are in the range of from about 0.3 milli meters to about 1.0 milli meters 29 The apparatus of claim 23 wherein said first and said second raised contacts have a substantially a triangular prism-like shape

30 The apparatus of claim 23 wherein said first and said second raised contacts have a substantially cylindrical-like shape.

31 The apparatus of claim 23 wherein said first and said second raised contacts each have a width and a thickness, and for each of said first and said second raised contacts, the ratio of its thickness to its width is in the range of from about 1:1 to about 1:5.

32 The apparatus of claim 23 wherein said first and said second raised contacts each comprises at least one of nickel plated copper and brass

33 The apparatus of claim 28 wherein. said first raised contact has a crest having a radius and said second raised contact has a crest having a radius, the radii having magnitudes in the range of from about 0.3 milli meters to about /.0 milli meters, said first and said second raised contacts each have a width and a thickness, and for each of said first and said second raised contacts, the ratio of its thickness to its width is in the range of from about 1:1 to about 1:5; and a plurality of angles at said positional crossing of said first and said second elongated mating surfaces are in the range of from about 30 degrees to about 150 degrees

34 The apparatus of claim 23 wherein said apparatus further comprises, said first platform is fixedly attached to said housing, and said second platform is movably attached to said housing, force transfer means responsive to said force from said handle, for placing said first and said second platform major surfaces in alternately further and closer proximity to each other in the alternate absence and presence of the applied force

35 The apparatus of claim 34 wherein. said first raised contact has a crest having a radius and said second raised contact has a crest having a radius, the radii having magnitudes in the range of from about 0.3 milli meters to about J.0 milli meters, said first and said second raised contacts each have a width and a thickness, and for each of said first and said second raised contacts, the ratio of its thickness to its width is in the range of from about /. / to about 1:5, and a plurality of angles at said positional crossing of said first and said second elongated mating surfaces are in the range of from about 30 degrees to about 150 degrees