Reverberation sound generator

• US 4,594,573 A
• Filed: 01/19/1983
• Issued: 06/10/1986
• Est. Priority Date: 01/19/1983
• Status: Expired due to Term

• Current Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Original Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Inventors: Tanahashi, Toshitaka, Yoshino, Muneki
• Primary Examiner(s): Caldwell, Sr., John W.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US06/459,199
• Time in Patent Office: 1,238 Days
• Field of Search: 340/62, 340/384 E, 331/139, 307/321, 307/257, 307/259
• US Class Current: 340/441
• CPC Class Codes: B60Q 1/54 for indicating speed outside of the vehicle

Abstract

A reverberation sound generator is provided for use as a warning generator for giving a warning to the driver of an automobile, for example. The reverberation sound generator has a capacitor connected in series with a power supply, a pair of diodes and a pair of resistors connected in series with the capacitor, and a sound generator circuit connected between the pair of diodes and the pair of resistors. A sound generation command switch is joined in series with the diodes and resistors. There is a circuit for discharging the capacitor. The capacitor can be controlled in its charging and discharging in response to closing and opening of the sound generation switch. When the capacitor is charged and discharged, the sound generator circuit produces reverberation sounds, respectively.

Claims

1. A reverberation sound generator comprising:

a power supply;

a capacitor connected to said power supply;

a pair of first and second diodes and a pair of first and second resistors which are connected in series to said capacitor, said diodes being connected in parallel to each other in opposite polarity, said resistors being connected in parallel to each other;

a sound generator circuit having terminals connected between said first diode and resistor and between said second diode and resistor, respectively, said sound generator circuit being energizable to produce a sound responsive to the difference between potentials at said terminals;

a sound generation command switch connected in series with said first and second diodes and resistors, said capacitor being chargeable in response to closing of said sound generation command switch; and

a discharging circuit connected between a junction between said sound generation command switch and said first and second diodes and resistors and another junction between said power supply and said capacitor.

2. A reverberation sound generator according to claim 1, wherein said discharging circuit includes a resistor.

3. A reverberation sound generator according to claim 1 or 2, wherein said sound generator circuit includes a driver transistor of the NPN type and a piezoelectric element having a feedback terminal drivable by said transistor.

4. A reverberation sound generator according to claim 1 or 2, wherein said sound generation command switch is controlled to be opened and closed intermittently at a predetermined frequency.

5. A reverberation sound generator according to claim 4, in association with an automobile, wherein said sound generation command switch is actuatable when the speed of the automobile exceeds a preset speed.