Abstract: A mechanical coupling device is provided with a pair of oppositely disposed arcuate jaws and integral arms defining a slot communicating with a cavity for connecting a shaft thereto. A tongue integral with the shaft is engaged by the jaws and suspended within the cavity, and the coupling device slides axially and laterally along the tongue and pivots along the arcuate jaws to eliminate end and side thrust of the shaft. A variable resistance control connected to the coupling device comprises a substrate closing one end of a housing and a rotatable driver disposed within the housing. A resistive path and a conductive collector path are disposed on the substrate along the same radius and a contactor comprising a pair of diametrically opposed contact fingers symmetrically disposed near the periphery of the driver engages the resistive and collector paths.

Abstract: A control comprises two variable resistance controls connected in tandem to a concentric shaft arrangement, an inner shaft of the concentric shaft arrangement containing an energy absorber, the inner shaft and the energy absorber providing an energy absorbing means for the control. The inner shaft made of glass-filled thermo-plastic further provides sufficient resiliency to prevent permanent shaft deformation and related knob wobble upon subjection of the shaft to severe impact and the energy absorber gradually absorbing the energy of impact minimizes axial movement of the inner shaft by eliminating the additional normally required tolerance. Additionally, the percentages of the glass and plastic mixture employed in making the shaft control torsional deflection.

Abstract: An indexing mechanism comprises a detent spring secured to a shaft and biased into engagement with a long wearing hill and valley insert secured to a housing. A variety of inserts can be secured to a standard housing providing a variety of switching positions and angles of indexing. A plurality of ears extending radially from the insert engage notches within the housing and a pair of spaced arms integral with each of the ears are biased against the walls of the notches to rigidly secure the insert to the housing. A stop element secured to the shaft is provided with a plurality of nubbins engaging a plurality of nubbin receiving notches provided in the detent spring for reinforcing the rotation of the detent spring in response to the rotation of the shaft.

Abstract: A variable resistance control containing a one-piece stamped mounting bracket having an integral collector ring for positioning a rotatable gear and having a pair of integral yokes for aligning a lead screw in driving relationship with the rotatable gear. A contactor constrained to rotate with the gear wipingly engages a resistance element. Each of the yokes comprises a pair of arms arcuately clinched around the lead screw to secure the lead screw to the mounting bracket. Integral with the gear are two outwardly extending resilient fingers for engagement with a respective one of the yokes to arrest rotation of the gear. Continued rotation of the lead screw after rotation of the gear has been arrested flexes the resilient finger toward the lead screw for driving the gear out of engagement with the lead screw. An aperture is provided in the lead screw for insertion of a shaft or tool for remote actuation of the control or for actuation of another control.

Abstract: An improved piezoelectric crystal unit provides a housing, a piezoelectric crystal element, and oppositely disposed mounting means for suspending the crystal element within the housing. A first set of three cradle means and a second set of three cradle means engage opposite faces of the crystal element. Each of the first set of cradle means contains a face member disposed adjacent the first face of the crystal element and an edge member disposed adjacent the peripheral edge of the crystal element and each of the second set of three cradle means contains a face member disposed adjacent the second face of the crystal element and an edge member disposed adjacent the peripheral edge of the crystal element. Integral with each of the first set of cradle means are elongated resilient legs exerting uniform pressures on one face of the crystal element and integral with each of the second set of cradle means are elongated resilient legs exerting uniform counterbalancing pressures on the other face of crystal element.

Abstract: An electrical switch suitable for use singly or in tandem with other switches and/or with a variable resistance control. Each of the tandem switch housing sections defines a cavity and provides an annular bearing member rotatably supporting the periphery of a disk shaped switch actuator. The switch actuators close the cavities of the respective switch housing sections and each of the switch actuators carries a cam disposed near its periphery in an interference path with a contact spring biased between spaced projections on common contact means. The contact spring is provided with a pair of end members pivotally secured to the common contact means and a U-shaped section joined to the end members. The cam engages the bight portion of the U-shaped section for moving the legs of the U-shaped section into and out of engagement with first and second contact means disposed in each housing section.

Abstract: A variable resistance control employs a substrate provided with a center aperture and a plurality of corner and intermediate locator means disposed about the periphery of the substrate. An adjusting; means constraining a contactor to rotate therewith is journaled in the aperture and the contactor wipingly engages a film type resistive path disposed on the surface of the subsrate. A first plurality of terminal members are disposed in the corner locator means of the substrate a first distance from the aperture. A second plurality of terminal members are disposed in a predetermined number of said intermediate locator means a second distance from the aperture at a distance closer than said first distance. At least one of the terminal members disposed in said intermediate locator means is in an interference path with a projection extending from the adjusting means to arrest rotation of the adjusting means.

Abstract: A variable resistance control comprises a resilient nonconductive annular skirt sandwiched between a pair of substrates. The skirt has an arcuate section and a pair of posts interconnected by a bridge section. Each of the substrates comprises a circular portion carrying a resistance film and an extending portion provided with apertures and engaged by the posts. A driver is rotatably carried by the control and contactors are constrained to rotate with the driver wipingly engaging the resistance films. The apertures in the extending portions of the substrates are in line with the posts and the periphery of the bridge section substantially coincides with edges of the extending portions. Terminals are secured to the extending portions of the substrates and comprise a head and a tail. The head is received in an aperture and a pair of spaced fingers integral with the terminal are clinched into engagement with the head disposed between the spaced fingers.

Abstract: A variable resistance control employing a support plate and a resistance element having a pair of spaced resistance paths applied on a base and rotatably mounted on the support plate. A pair of terminals with integral contacts are secured to the support plate and are disposed intermediate the base and the support plate. The pair of resistive paths are concentrically disposed on a surface of the base and electrically connected to each other. Each of the contacts engages a respective one of the resistive paths. In the assembly of the control, terminals are initially joined by a bridging member and, after the terminals are secured to the support plate, the bridging member is severed from the terminals providing a pair of separate terminals with integral contacts.

Abstract: A variable resistance control comprises a resistance element supported on an electrically conductive supporting plate. A driver connected to the supporting plate is provided with a knob and with an integral stabilizing and particle excluding skirt. The ratio of the diameter of the stabilizing skirt to the diameter of the knob is relatively high. The stabilizing skirt rotatably engages the resistance element and encloses a contactor carried by the driver and prevents foreign particles from engaging the contactor. Indicator means integral with the stabilizing skirt and projecting beyond a truncated portion of the knob visually indicate the angular position of the contactor. The indicator means also engages a stop integral with the supporting plate and extending between the legs of the resistance element to arrest rotation of the contactor. Terminals provided with staggered ears are secured to the legs of the resistance element.

Abstract: A switch assembly provides a plurality of slide switches. Each switch employs a flexible guide rod cantilevered within a common housing providing a first contact. A second contact is biased into electrical contact with each guide rod and an insulative cam carried by a switch actuator is supported by each guide rod for rectilinear movement therealong in an interference path with the second contact to separate the second contact from the guide rod. The flexible guide rod is movable with respect to the second contact and provides the means to align the switch actuator and the cam in an interference path with the second contact. Each switch actuator provides a pair of side walls enclosing a respective guide rod and second contact suspended therebetween.

Abstract: A plug-in shaft is provided for insertion into a noncircular opening provided in a driver and integral hub of a variable resistance control providing a means to alter the rotational torque of the control. Integral with the hub is a dish shaped abuttment section and a driver engagement portion of the shaft supports a plurality of nubbins engaging the abuttment section of the hub upon insertion of the shaft into the noncircular opening to secure the shaft in a predetermined position within the slot. The nubbins engaging the dish shaped abuttment section provide radial pressure on the hub and restrain the axial movement of the shaft within the noncircular opening. An alignment portion of the shaft contiguous with the driver engagement portion rigidly prealigns the shaft in an upright and intact manner within the noncircular opening before the engagement portion and nubbins engage the noncircular opening.