Abstract:
A push-button switch using one dome sheet of plastics with an electrode on one face and a second flat sheet of plastics with an electrode on the face opposite the first one. Between the sheets and below the second one plates of rigid material with holes below the dome are arranged. When the button is depressed the dome snaps over to the other side of the plastic sheet and the electrode contacts the electrode on the flat plastic sheet. By the hole in the plate below the flat sheet a chatter-proof contact is established.
Abstract:
Keyboard having contactors and contacts which are selectively urged against one another by depression causing engagement of one by the other, the keyboard having at least contactors or contacts or both which are constructed of a conductive polymeric composition such that upon engagement of a contactor with a contact there is exhibited substantially reduced bounce after repeated closure of contactor against contact even at micro ampere current levels.
Abstract:
An inexpensive, yet highly reliable, electrical switch contact assembly with excellent human factors considerations includes an electrical contact assembly having a plurality of switch positions, a cover plate disposed adjacent the switch contact assembly with an aperture for each switch position, and at each switch position an apertured key, a follower disposed within the key aperture, a cap containing the follower within the key aperture and key and follower springs biasing the key and follower respectively to provide separate and independent control over key actuation and switch contact closure forces. A contact engagement post of the follower may be accurately positioned above a switch contact notwithstanding variations in spring characteristics an a curvilinear engagement surface assures optimum distributed switch closure pressure for high reliability switch actuation. Switch contact patterns with oppositely disposed and interdigitated circularly and radially extending portions assure the security of multiple switch closure engagements.
Abstract:
A push-button switch comprises a substrate on which two conductive networks are formed, those networks comprising adjacent but separated conductive paths, a push-button member with a contact member thereon being mounted on the substrate with the contact member normally above and in registration with the separated conductive paths. The contract member is formed of elastic and electrically conductive material and is adapted when it is pushed down via the push-button member to engage the substrate, and hence the separated conductive paths, over an appreciable area, thereby ensuring effective switch operation.
Abstract:
An apparatus and method for de-bouncing keypad inputs is disclosed including interrupting a processor upon detecting a key press, reading input signals from the key pad to determine an initial port value and starting a timer. A keypad interrupt is disabled and processing resumes until expiration of the timer. The timer interrupts the processor and the input signals are read a second time and combined with the initial port value to determine a key identifier. The timer is started again and processing resumes. Upon expiration of the timer the processor checks for key release. If release is not detected, the timer is again started. If release occurs, the timer is disabled and the keypad interrupt is enabled.
Abstract:
In an electrical switch, in particular an electrical microswitch, has at least one electrical contact designed as a hollow-shape section of a component of an electrically conducting material. In this electrical switch, the occurrence of vibrations with the introduction onto an opposing contact is prevented.
Abstract:
In an electrical switch, in particular an electrical microswitch, has at least one electrical contact designed as a hollow-shape section of a component of an electrically conducting material. In this electrical switch, the occurrence of vibrations with the introduction onto an opposing contact is prevented.
Abstract:
An apparatus and method for de-bouncing keypad inputs is disclosed including interrupting a processor upon detecting a key press, reading input signals from the key pad to determine an initial port value and starting a timer. A keypad interrupt is disabled and processing resumes until expiration of the timer. The timer interrupts the processor and the input signals are read a second time and combined with the initial port value to determine a key identifier. The timer is started again and processing resumes. Upon expiration of the timer the processor checks for key release. If release is not detected, the timer is again started. If release occurs, the timer is disabled and the keypad interrupt is enabled.
Abstract:
A membrane keyboard has two spaced flexible membranes (1 and 2) carrying contact pad assemblies. Acoustic pads (15) of expanding ink are printed on the top surface of the upper membrane (2) between the contact pads (4) and the key buttons used to operate the contact switches formed by the pairs of opposed contact pads, thus reducing the acoustic noise and improving the contact bounce characteristic.Optionally, printed expanding ink is also used to form the spacer (5) between the membranes (1 and 2).
Abstract:
A pressure responsive, variable resistance, analog switch has first and second conductors interleaved in spaced-apart relationship and disposed on a base member. An insulative spacer ring is positioned around and rises above the first and second conductors. A resilient cover sheet is attached to the top of the insulative spacer ring in spaced relationship over the conductors to define an enclosure between the resilient cover sheet and the base member. A pressure sensitive resistive conductor composition is disposed on the resilient cover sheet or on the conductors in the enclosure to interconnect a resistance between the first and second conductors when the resilient cover sheet is depressed against the conductors. The amount of resistance so interconnected varies inversely to the amount of pressure exerted.