The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 29, 1991
Filed:
Nov. 16, 1990
Joseph Truchsess, City Island, NY (US);
Other;
Abstract
An inexpensive yet effective circuit for producing an irregular pulse train of variable frequency and duty cycle, particularly for generating simulated sounds, such as engine sounds for toy vehicles, is disclosed. The circuit comprises an integrated circuit including a plurality of Schmitt trigger inverters (U1A, U1B) configured for oscillation at different frequencies, and a resistance element (R3, R7) in series with one, and preferably both, of the power supply connections to the inverters, with the circuit output comprising the output of one of the Schmitt trigger inverters (U1B). In a preferred embodiment, a capacitance element (C4) is connected between the output of a Schmitt trigger inverter and its system voltage input for further modulating the circuit output.