Low current switching apparatus having detent structure providing tactile feedback
First Claim
1. Low current switching apparatus comprising, in combination:
- spaced stationary conductive elements;
a conductive member overlying said stationary conductive elements in spaced relation thereto;
an operator movable from a first position to a second position effecting depression of said conductive member into bridging current conducting relation with said stationary conductive elements; and
detent means comprising;
a normally planar flat beam leaf spring distinct from said conductive member;
means fixing opposite ends of said leaf spring, supporting said leaf spring in a bowed, flexed condition; and
means on said operator bearing upon an intermediate portion of said leaf spring deflecting said intermediate portion from a convex condition to a concave condition upon movement of said operator from said first position to said second position, said leaf spring initially applying an increasing force to said operator resisting said operator movement and changing to a decreasing force at a predetermined point in said movement to provide tactile feedback to said operator.
3 Assignments
0 Petitions
Accused Products
Abstract
Pivotal movement of a switch actuator drives a finger projecting from the actuator against a convexly bowed leaf spring, depressing an intermediate portion of the leaf spring to an unstable concave condition. The leaf spring resists the actuator movement, initially with an increasing force but changing to a decreasing force at a predictable point in actuator movement to provide tactile feedback at an operator affixed to the actuator. The leaf spring is a flat beam. The spring foce and point of changeover can be readily and predictably varied during manufacture by selecting springs having different widths, thicknesses or other variable parameters. A modular block holds the spring in the bowed condition and is positioned relative to the actuator finger by a support plate. The actuator finger drives the spring against a conductive rubber block, compressing the block against spaced conductors on a printed circuit to complete the circuit. A plurality of such switches are made in a common package by layering a printed circuit, insulator sheet, conductive rubber sheet with raised bosses, detent support plate and a plurality of detent blocks with bowed springs, between a base and a cover. Back lit illumination is provided by a light pipe trapped against the cover as an additional layer. A microprocessor board, connected to the internal printed circuit, is attached to the switch housing exteriorly of the base.
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Citations
37 Claims
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1. Low current switching apparatus comprising, in combination:
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spaced stationary conductive elements; a conductive member overlying said stationary conductive elements in spaced relation thereto; an operator movable from a first position to a second position effecting depression of said conductive member into bridging current conducting relation with said stationary conductive elements; and detent means comprising; a normally planar flat beam leaf spring distinct from said conductive member; means fixing opposite ends of said leaf spring, supporting said leaf spring in a bowed, flexed condition; and means on said operator bearing upon an intermediate portion of said leaf spring deflecting said intermediate portion from a convex condition to a concave condition upon movement of said operator from said first position to said second position, said leaf spring initially applying an increasing force to said operator resisting said operator movement and changing to a decreasing force at a predetermined point in said movement to provide tactile feedback to said operator. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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13. Low current switching apparatus comprising a multiple layer assembly comprising, in combination:
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a first layer comprising a rigid insulating base; a second layer comprising a printed circuit having spaced conductor elements defining switch contacts; a third layer comprising an insulator covering said printed circuit and having an opening aligned with said switch contacts; a fourth layer comprising a block of conductive rubber overlying said switch contacts in spaced relation thereto; a fifth layer comprising a rigid insulating detent support having an aperture aligned with said block and said switch contacts; said first through fifth layers being secured in a sandwich relation by a cover enveloping said layers and being attached to said base; detent means comprising a flat beam leaf spring; means on said detent support fixing opposite ends of said leaf spring at respective opposite sides of said aperture, said leaf spring being disposed over said aperture and being bowed toward said cover away from said block; switch actuator means pivotally mounted in said cover having an operator portion extending externally of said cover, movement of said actuator means from a first position to a second position effecting compression of said conductive rubber block into current conducting bridging relation with said switch contacts; and means on said actuator means bearing upon an intermediate portion of said leaf spring deflecting said intermediate portion from a convex to a concave shape during said movement of said actuator means, said leaf spring initially applying an increasing force to said actuator means resisting said movement and changing to a decreasing force at a predetermined point in said movement, thereby providing tactile feedback to said operator. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 23)
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22. Low current switching apparatus as defined in 13 wherein pivotal mounting of said switch actuator means comprises an axle on said switch actuator means received within journals provided in said cover, said journals being open toward said detent support;
- and said detent support comprises upstanding bearing posts aligned with said journals, distal ends of said bearing posts closing said open side of said journals.
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24. Low current switching apparatus comprising, in combination:
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an insulating base; a printed circuit supported by said base, said circuit having a pair of spaced conductive elements defining switch contacts; insulating means covering said printed circuit having an opening aligned with said switch contacts; a thin member disposed over said insulating means positioning a conductive rubber block on said insulating means over said switch contacts in spaced relation thereto; a detent support plate disposed on said thin member, said plate having an aperture aligned with said switch contacts, said conductive rubber block extending through said aperture; detent means comprising a flat beam leaf spring and means fixedly mounting opposite ends of said leaf spring at respective opposite sides of said aperture, said leaf spring extending across said aperture bowed away from said rubber block; an insulating cover attached to said base, said cover and said base constituting an insulating housing; an actuator pivotally mounted in said housing having an operator portion extending through said cover, said actuator being movable from a first position to a second position effecting compression of said conductive rubber block upon said switch contacts, thereby establishing bridging current conduction between said switch contacts; and means on said actuator bearing upon an intermediate portion of said bowed leaf spring, said leaf spring biasing said actuator to said first position and resisting said movement to said second position, said means deflecting said intermediate portion of said leaf spring during said movement, said intermediate portion changing from a convex to a concave shape, said spring initially increasing force resisting said movement and changing to a decreasing force at a predetermined point in said movement substantially concurrently with the establishment of current conduction between said switch contacts, thereby providing tactile feedback to said operator. - View Dependent Claims (25, 26, 27, 28, 29, 30)
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31. A detent providing a tactilely discernible change in force to a movable member comprising, in combination:
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a normally planar flat beam leaf spring; means fixing opposite ends of said leaf spring, supporting said leaf spring in a bowed, flexed condition; a movable member movable from a first position to a second position; and means on said movable member bearing upon an intermediate portion of said leaf spring deflecting said intermediate portion from a convex condition to a concave condition upon movement of said movable member from said first position to said second position, said leaf spring initially applying an increasing force to said movable member resisting said movement and changing to a decreasing force at a predetermined point in said movement to provide tactile feedback to said movable member, wherein said force of said leaf spring is predictably varied by providing a selected width and a selected thickness for said flat beam leaf spring to provide a desired tactile feedback. - View Dependent Claims (32, 33)
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34. A detent providing a tactilely discernible change in force to a movable member comprising, in combination:
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a normally planar flat beam leaf spring; means fixing opposite ends of said leaf spring, supporting said leaf spring in a bowed, flexed condition; a movable member movable from a first position to a second position; and means on said movable member bearing upon an intermediate portion of said leaf spring deflecting said intermediate portion from a convex condition to a concave condition upon movement of said movable member from said first position to said second position, said leaf spring initially applying an increasing force to said movable member resisting said movement and changing to a decreasing force at a predetermined point in said movement to provide tactile feedback to said movable member, wherein said movable member comprises a switch operator effecting actuation of switch contacts when moved from said first position to said second position, said switch contacts being distinct from said flat beam leaf spring. - View Dependent Claims (35, 36, 37)
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Specification