JPS61241224A - Electrical horn - Google Patents

Abstract

PURPOSE:To make it possible to satisfactorily generate reverberations, by changing the width of output pulses in accordance with an output which is generated from a damping circuit after turning off a switch and which gradually decays. CONSTITUTION:When a switch 17 is closed to blow an electrical horn 10, a capacitor 18 is charged, and when the switch 17 is opened, the capacitor 18 is discharged through a resistor 19 so that a decaying output is delivered from a damping circuit 20 to a voltage-time converting circuit 15 which receives output pulses from a time-sharing pulse generating circuit 14 and which delivers intermittent pulses in accordance with the above-mentioned decaying output. Acordingly, the electrical horn 10 is energized by means of a transistor 11 in accordance with these intermittend pulses, thereby it is possible to generate the so-called reverberations whose sound pressure which is sensible to human ears and which is gradually decreased.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an electric horn, and more particularly to an electric horn suitable for use in an automobile for generating an alarm sound.

[Summary of the invention]

The present invention provides an electric horn adapted to drive one noise means by an electrical driving force, after opening a switch to stop the operation of the horn, a gradually damping output generated by a damping circuit is used. , the pulse width applied to the horn is gradually reduced, thereby producing reverberant sound similar to that of an air horn.

[Prior Art 1] Air horns have conventionally been widely used as horns installed in automobiles to generate alarm sounds. This air horn has vibration characteristics as shown in FIG. 5, and even when the drive of this horn is stopped (OFF), the sound pressure does not drop suddenly but gradually attenuates. Therefore, reverberant sound is generated, and unique sound quality due to air resonance is generated. For these reasons, air horns are widely used. [Problem that the invention aims to solve] On the other hand, although electric horns have the advantage of being easy to install and being inexpensive, they are inferior to air horns in terms of sound quality and are rarely used. Ta. This is the same as a normal electric buzzer, and uses a combination of an electromagnet and a movable contact attached to a diaphragm to generate a vibrating sound by applying direct current.
The sound of an electric horn is the vibration sound of the diaphragm itself, and exhibits the characteristics shown in FIG. In other words, when the current is cut off, the sound pressure instantly drops to zero and the sound disappears. Attenuating the voltage is considered in order to generate reverberant sound, but since the relationship between voltage and sound pressure is not necessarily proportional, the diaphragm stops vibrating before the voltage drops too much, causing the diaphragm to stop vibrating. The characteristics are close to those shown in Figure 6, and no great effect can be obtained. The present invention has been made in view of these problems, and an object of the present invention is to provide an electric horn that generates residual W sound and whose sound pressure gradually attenuates after the switch is shut off. It is something. Means for Solving Problem K] The present invention provides an electric horn in which a vibrating means is driven by an electric driving force, which includes a pulse generating circuit that generates a pulsed voltage applied to the horn, and a switch. and a pulse width changing means for changing the width of the output pulse of the pulse generation circuit in accordance with the output of the attenuation circuit. be.

[Operation 1] Therefore, according to the present invention, after the switch that drives the electric horn is cut off, the output of the attenuation circuit is gradually attenuated, and the width of the output pulse of the pulse generation circuit is gradually attenuated in accordance with the output of the attenuation circuit. It becomes smaller and is added to the electric horn, which causes the electric horn to generate reverberant sound and gradually reduce the sound pressure. Therefore, it is possible to obtain an electric horn having characteristics similar to those of an air horn. [Embodiment] The present invention will be described below with reference to an illustrated embodiment. FIG. 1 shows a drive circuit for an electric horn 10 according to an embodiment of the present invention, and the electric horn 10 is connected to a battery 12 via a driving switching transistor 11. As circuits for controlling this transistor 11, an oscillation circuit 13, a time-division pulse generation circuit 14, and a voltage-to-time conversion circuit 15 are provided, respectively. Further, the voltage one-hour conversion circuit 15 is connected to the battery 12 via a switch 17, and the switch 17
An attenuation circuit 20 consisting of a capacitor 18 and a resistor 19 is connected between the converter circuit 15 and the converter circuit 15 . Next, the mechanical structure of this electric horn 10 will be explained. As shown in FIGS. 2 and 3, the horn 10 is equipped with a diaphragm 21 inside its casing. A vibrator is connected to the switching transistor 11. Also this horn 1
0 is equipped with a resonance tube 22, which causes the sound generated by the diaphragm 21 to resonate. In the above configuration, the oscillation circuit 13 has, for example, 20
It generates an oscillation output of Hz and supplies this output to the time division pulse generation circuit 14. Therefore, the pulse generating circuit 14 generates a 20 Hz pulse and supplies this pulse to the voltage one-hour converter 15. This pulse is a pulse as shown in FIG. 4C. On the other hand, when switch 17 is closed, it produces an output as shown in FIG. 4A. By closing this switch 17, the capacitor 18 is charged. Since this capacitor 18 is discharged through the resistor 19 when the switch 17 is opened, the attenuation circuit 20 produces an attenuated output as shown in FIG. 4B. The voltage one-time conversion circuit 15 receives the pulse 201-1 z and converts the voltage on the attenuation circuit 20 side at the time of pulse input to 0.0.
In order to convert it into a time of 5 seconds or less, express it as a pulse width, and output it, an output as shown in Figure 4 is generated by the output pulse of the pulse generation circuit 14 and the attenuation output of the attenuation circuit 20, This output drives transistor 11. That is, when the output of the attenuation circuit 20 is not attenuated, the conversion circuit 15 supplies a continuous pulse to the transistor 11. This pulse may be a 200 Hz pulse, for example, which causes the diaphragm 21 of the electric horn 10 to vibrate and generate an alarm sound. Then, when the switch 17 is turned off and the output of the attenuation circuit 17 is gradually attenuated, the voltage temporarily open conversion circuit 15 transmits intermittent pulses to the transistor 1, as shown in the fourth diagram.
1, and the width of this pulse gradually becomes smaller. Therefore, by changing the pulse width in this manner, the sound pressure felt by the ears gradually decreases, as shown by the dotted line in the fourth diagram, and the electric horn 10 begins to generate reverberant sound. Moreover, the diaphragm 2 of this electric horn 10
Since the sound generated by the horn is resonated by the resonance tube 22, the effect of the reverberant sound is further enhanced, and it becomes possible to generate an alarm sound that is clearly different from that of a conventional electric horn. As described above, according to the electric horn 10 according to the present embodiment, the voltage applied to the horn 10 is made into a pulse, and the width of this pulse is changed after the switch 17 is opened, thereby increasing the sound energy per time. The sound level is gradually attenuated to control the loudness of the sound perceived by the ears. Therefore, after turning off the switch 17 of the horn 10, it is possible to gradually narrow the pulse width for about one second, and it is possible to generate an effect similar to reverberation. Furthermore, by causing this sound to resonate with the resonance tube 22, it becomes possible to generate a resonance effect similar to that of an air horn. The frequency of the pulse is set at 20 Hz, because if the frequency is too high, the pulse itself will be heard as a sound. Moreover, if the frequency of this pulse is made too low, breaks in the sound of the horn 10 will become perceptible to the ears. Effect of the Invention 1 As described above, the present invention applies a pulsed voltage generated by a pulse generating circuit to the horn, and when the horn switch is cut off, the attenuating output of the attenuating circuit is applied to the horn. The width of the output pulse of the generating circuit is gradually reduced in accordance with the above. Therefore, it becomes possible to generate reverberant sound even though it is an electric horn, and it becomes possible to provide an electric horn having a reverberant effect.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing a drive circuit of an electric horn according to an embodiment of the present invention, Fig. 2 is a front view of the electric horn, Fig. 3 is a side view of the same, and Fig. 4 is an operation of the electric horn. FIG. 5 is a graph showing the characteristics of a conventional air horn, and FIG. 6 is a graph showing the characteristics of a conventional electric horn. In addition, in the symbols used in the drawings, 10... electric horn 13... oscillation circuit 14... time division pulse generation circuit 15... voltage one time conversion circuit 17... switch 20... attenuation circuit. be.

Claims (1)

[Claims] In an electric horn in which the vibrating means is driven by electrical driving force, a pulse generation circuit generates a pulsed voltage applied to the horn, and a damping circuit generates an output that gradually attenuates after the switch is cut off. and pulse width changing means for changing the width of the output pulse of the pulse generating circuit in accordance with the output of the attenuation circuit.