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:
A pressure transducer device particularly useful in an electronic musical instrument includes a flexible base folded to define upper and lower flexible base portions, a donut-shaped first spacer between the upper and lower base portions and a resiliently deformable diaphragm attached about its periphery to the upper flexible base portion with a second donut-shaped spacer therebetween. A center region of the diaphragm laterally spaced from the second spacer is adhesively attached to a central region of the upper flexible base portion so that the upper flexible base portion moves inwardly and outwardly in response to the movement of the diaphragm. A pair of conductors are disposed on the folded flexible base member to face one another. A pressure responsive composition disposed over the conductors provides a contact resistance across the pair of conductors which varies inversely with the amount of pressure force exerted against the diaphragm. The upper flexible base portion may be attached between the first and second spacers about its entire periphery or at a small hinge region with the upper base portion being a flap movable about the hinge region in the region surrounded by the first spacer.
Abstract:
The present invention switch comprises a pair of electrodes separated by resilient resistive material which changes resistance several orders of magnitude in response to light pressure. Sensing and amplifying means are provided to detect a predetermined change in resistance. An array of a plurality of such switches may be arranged in a switching matrix to provide any desired form of switch controls or a keyboard for numerous electronic applications.
Abstract:
Different from conventional push-button switches with which an electric circuit is closed and opened as the button top is pushed with a finger tip and as the finger tip is withdrawn from the button top, respectively, the inventive push-button switch operates in a unique manner that the electric circuit is opened already as the pushing force by the finger tip is still on the way of increasing. The inventive push-button switches utilize the delicate snap back action taking place as the strain in the snap spring portion in the diaphragm covering of the switch exceeds a certain critical point so as to spontaneously pull apart the movable contact member on the inward surface of the covering from the fixed contact points on the base plate while the button top is still under pushing with a finger tip. The inventive push-button switch is advantageous because of the absence of the transient disturbances in the circuit such as chattering and bouncing.
Abstract:
An economical yet versatile dual spring actuator switch assembly providing an excellent tactile impression includes a planar switch closure assembly having domed protrusions extending from a surface thereof to provide switch closure when depressed and a switch actuator assembly. The easily assembled switch actuator assembly includes a cover plate with a guiding, key receiving plate aperture disposed therein opposite each protrusion, a plurality of keys, each key having a central key aperture, and a guide post within the central key aperture and being slideably received by a different plate aperture, a plurality of followers, each disposed adjacent a different protrusion and having a central aperture slideably receiving a guide post in guiding, mating relationship, a plurality of first springs, each maintaining a repulsive force between a different key and the surface, and a plurality of second springs, each coupling a different key to a follower to communicate a switch closure force to a protrusion upon depression of a key. The double spring arrangement permits independent selection of key and protrusion actuation forces and buffers each protrusion from its associated key for longer switch lifetime.
Abstract:
The disclosure relates generally to key assemblies employed in electrical switch operating keyboard devices and more particularly to the improved assembly of parts forming an individual depressible key on such a keyboard. Each key assembly is comprised of parts cooperatively interfitting to provide both audio and tactile feedback for the keyboard as well as a bifurcated electrical contact provision. Included in each key assembly is a spring having a buckling beam member with two end supports that will resist a key depression, a hermetic rubber pad that will also resist key depression and a pair of spring straddling members depending from the key assembly for conveying forces employed to depress the key to the switch associated with the assembly to effect closure of the same as well as for substantially reducing if not eliminating a detrimental contact bounce encountered in the operation of such assemblies. The force transmitting pair of depending members cooperate with the straddle spring to provide a rocker or teetering motion in conjunction with the desired bifurcated action for assuring closure of the contacts.
Abstract:
A low profile electromechanical keyboard switch, displaying very low electrical bounce. The switch key top bears against a generally cylindrical plunger which has a depressed flat portion on its side engageable with a tactile ball biased by a spring nested in the switch housing. Upon application of a force to the key top which exceeds a threshold value, the tactile ball is displaced from the flat and over the shoulder defined between the depressed flat and the cylindrical portion of the plunger. Sudden, positive movement of the plunger against an underlying contact leaf ensues. The contact leaf is branched into multiple contact fingers, and arranged with respect to an underlying contact plate so that wiping contact occurs between fingers and plate. The switch housing is configured to carry sufficient diodes and resistors to assure full control and encoding functions in the keyboard in which such switch may be mounted.
Abstract:
A contact bounce reduction system including: a movable member, and a contact bounce damping device including: a body, a first ball and a second ball, a first resilient member and a second resilient member, a piston. The first resilient member holds the first ball in the seat and the second resilient member holds the second ball in the seat when the piston is in a default extended position, and a third resilient member biases the piston towards the default extended position. The movable member actuates the piston towards the retracted position, causing the first ball and the second ball to move radially out from the seat, and the third resilient member to accumulate energy.
Abstract:
The present invention discloses a de-bouncing keypad and a preparation method thereof, wherein the keypad is composed of a rubber substrate and a metal contact having three layers of layered structures. A layer of tin alloy or lead alloy is plated on a surface of the metal contact by electroplating or chemical plating. The metal contact plated with the tin alloy or lead alloy has excellent contact bouncing resistance and arc-ablation resistance, and the metal contact is further composited with the rubber to shape and prepare the rubber de-bouncing keypad.
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.