Abstract: A panel mount for supporting an electronic device at a hole in a control panel and mountable with access to only the front of the panel. It has a housing that slides into a tubular elastomeric grommet. During installation, an expander segment of the housing slides within a bulging segment of the grommet to expand the grommet inward of the hole and for retaining the components within the hole. A tubular male pre-assembly segment on the exterior surface of the tubular housing permits the housing to be pre-inserted partially into the grommet without expanding any part of the grommet radially outward in preparation for inserting the assembled housing and grommet into the panel hole. A withdrawal lock prevents the housing from sliding axially out of the grommet after installation. The withdrawal lock includes a shoulder formed on the grommet and a shoulder formed on the housing.

Abstract: A piezoelectric audible signal that has at least two, frusto-conical, coil spring conductors extending between and in unsoldered electrical connection with, at one end, different contact pads on the printed circuit board and, at their opposite ends, the piezoelectric disk. A retaining and spacer ring is interposed between the disk and the printed circuit board and has at least two, frusto-conically shaped, spring retaining cavities that matingly receive the spring conductors in a manner that retains the spring conductors against movement away from the printed circuit board when the ring is attached to the printed circuit board.

Abstract: A combined and integrated audible and visual signal. A signal case is constructed of a light transmissive material and includes an exposed front end cover with one or more sound transmitting apertures and a tubular wall extending transversely from the exposed end cover for extending through a hole in a mounting panel. A transducer is mounted within the tubular wall and includes a diaphragm that is spaced from the exposed cover. Light sources are mounted to face the diaphragm. The tubular wall in the region between the cover and a plane transverse to the tubular wall through the diaphragm is, in the axial direction, smoothly continuous with no angled bends.

Abstract: A device for housing a sound-emitting transducer including a housing and a cap. The housing has a chamber defined by a cylindrical sidewall and an endwall with apertures. The cap mounts to the housing, and has apertures that can register with the apertures in the endwall. A groove is formed between the cap and teeth formed at its circular outer periphery. The cap's circular lip is inserted into the groove by deforming the cap slightly. Thus, relative movement is permitted between the cap and housing for registering and de-registering the apertures on the cap and housing. This controls the volume of the sound-emitting transducer.

Abstract: A combined and integrated audible and visual signal. A signal case is constructed of a light transmissive material. The case includes an exposed front end cover with one or more sound transmitting apertures for transmitting of sound out of the case. The case also has a tubular wall extending transversely from the exposed end cover for extending through a hole in a mounting panel. A piezoelectric transducer is mounted within the tubular wall and includes a diaphragm that is spaced from the exposed cover a distance to form an audio enhancing cavity between the diaphragm and the cover. A circuit board is also mounted within the tubular wall and spaced from the diaphragm on the opposite side of the diaphragm from the cover. Light sources are mounted to a surface of the circuit board facing the diaphragm. The tubular wall in the region between the cover and a plane transverse to the tubular wall through the diaphragm is, in the axial direction, smoothly continuous with no angled bends.

Abstract: A controller, either a microprocessor or finite state machine, is used to generate a pulse train whose frequency and duty cycle can be varied to alter the frequency and amplitude of the output of a driven audio transducer. The ability to control both frequency and amplitude allows programmatic synthesis of many audio effects such as steady tones, warbles, beeps, sirens and chimes with no hardware or circuit changes. The transducer can be a piezoelectric bender or a speaker. The output of the controller controls a switch that builds current in an inductor when the switch is on. When the switch is turned off, the energy stored in the inductor is dumped into the audio transducer, either directly or through intermediate capacitor storage. This allows the generation of voltages across the transducer many times the supply voltage.

Abstract: A fastener, such as a housing, for mounting to a structure, such as a panel, that has an aperture formed therethrough. The fastener includes a shank member and an annular nut member that is configured to align coaxially with the shank member. The shank member is inserted through aperture in the structure and the nut member is placed on the shank member. Teeth on the radially outwardly facing surface of the shank member engage a pawl, such as one or more teeth, on the radially inwardly facing surface of the nut member to lock the nut member to the shank member. Removal of the nut member is effected by rotating the nut member to disengage the pawl from the teeth, thereby permitting longitudinal displacement of the nut member off of the shank member.