CH329938A - Mechanical-electrical transformer - Google Patents

Description

The subject of the present invention is a mechanical-electrical transformer comprising a radioactive source endowed with at least one part of the radiation reached by a semi-conductor endowed with electrical conductivity which varies according to the radioactive radiation to which it is subjected. , this semiconductor forming part of an electrical circuit, means being provided for varying, as a function of a mechanical quantity, the value of the radiation reaching the semiconductor, so as to generate a corresponding variation of the current in the electrical circuit.

The accompanying drawing represents, schematically and by way of example; three embodiments of the object of the invention.

fig. 1 represents a transformer intended to modulate an electric current as a function of a mechanical displacement.

fig. 2 represents a mechanical-electrical transformer constituting a mierophone. fig. 3 shows another embodiment applied to a pick-up for a record player.

The embodiment represented in FIG. 1 comprises a radioactive source 1 adopts at least a part of the radiation hitting a semiconductor 2 adopts the electrical conductivity varies according to the radioactive radiation to which it is subjected. This semiconductor forms part of an electrical circuit comprising a battery 3 and a measuring instrument 4. A lever 5, articulated at 6, carries a screen 7 intended to absorb the radioactive radiation from the source 1. This screen 7 can be consisting of a metal foil covered with a layer of lead.

When one acts on the end 8 of the lever 5 to move it in the direction of the arrows f1 and f2, an modifies the position of the screen 7 with respect to the source 1, which causes the value of the radioactive radiation reaching the semiconductor 2. This results in a variation of the electrical conductivity of the latter, so that the current supplied by the Battery 3 varies accordingly, which can be checked by the reading of the instrument 4.

fig. 2 relates to another form of execution in which the first semiconductor 2 is placed inside a box 9 sealed in a sealed manner by a membrane 10. The latter is tightened by a pike 11 screwed onto the box 9 The source of radioactive material is constituted by a film 12 of strontium 90 which is deposited on the membrane by evaporation in a vacuum. Box 9 is filled with gas absorbing radiation from the radioactive source. The RTI ID="0001.0268" WI="10" HE="4" LX="1232" LY="2178"> electrical circuit of which the first semiconductor 2 forms part comprises a Battery 3 and a loudspeaker 13. This mechanical-electrical transformer constitutes a microphone and makes it possible to obtain sufficiently high current variations to enable the loudspeaker 13 to be actuated without using an amplifier. The acoustic vibrations arriving on the membrane 10 cause the latter to vibrate, so that the thickness of gas between the radioactive source 12 and the first semiconductor 2 varies according to these acoustic vibrations. The radiation reaching the semiconductor 2 is therefore more or less attenuated depending on the thickness of the gas traversed, so that the current delivered by the battery 3 is modulated as a function of these vibrations. The device according to FIG. 2 achieves an amplification of 60 decibels.

Thanks to this high amplification, it is possible to create miniature amplifiers for people who are hard of hearing. These amplifiers consist of a microphone of the type shown in fig. 2, but smaller in size, by an ordinary miniature battery and by a small footprint earpiece. The dimensions of these amplifiers can be small enough that the whole thing can be logoned in the ear within the ear canal. Such a device is very advantageous compared to known amplifiers, because the latter include a dann Foreille logo earphone and an amplifier generally hidden in the clothing of the person wearing the device. It is therefore necessary to connect the earphone to the amplifier by a flexible and unsightly effect. The fact of providing the microphone inside the auditory canal is very advantageous, because the ear regains its directional sensitivity, on the one hand, and the absence of your cord is very pleasant, on the other hand.

fig. 3 represents a form of similar exdcutio@n Jans which a box 9 contains two semiconductors 2 and 2a between which is placed a lavra 14 covered with radioactive material. This laure is articulated at 15 On box 9 and carries at its end a needle 16 intended to cooperate with the groove of a disc: The electrical circuit comprises a battery 3 which is connected between the midpoint of a winding 17 of a transformer 18 and the current leads to the two semiconductors. The latter are respectively connected to each of the ends of the winding 17.

When laura 14 is halfway between the two semi-conductors, the conductivity of those -this is equal and the current delivered by the battery 3 is divided into two equal parts passing through each half of the winding 17 in direction. opposite. As the laurel 14 approaches one semiconductor and moves away from the other, the current increases in one half of the winding 17 and decreases in the other half of it, so that a voltage appears. terminals of the secondary winding of transformer 18 which is connected to a loudspeaker 13. It is therefore seen that the vibrations of the laurel 14 generate an electric current of corresponding frequency in the secondary of the transformer 18. The box 9 can It should also be filled with a gas which absorbs radioactive radiation.

Of course, many modifications could be made to the embodiments shown and other applications found for the mechanical-electrical transformers described. In particular, the value of the radiation reaching the semiconductor can be modified by simply varying the position of the radioactive source relative to the semiconductor, unless it is necessary to place an absorbing gas in the path of the radioactive rays. . 0n could also replace in the example of FIG. 2 the solid radioactive source fixed to the membrane 10 by a radioactive gas filling the chamber delimited by the box 9 and the membrane 10. In this case, it is clear that when the membrane exerts a compression on the gas, the radiation reaching the semiconductor 2 increases in intensity.

It is also known that rays of type a have an efficiency depending on their distance from the source, and that at a certain distance from this source, of the order of 4 to 5 cm in general, their efficiency drops sharply to zdro. It is clear that if the source is mobile and is far from the semiconductor, precisely by this critical distance, an will obtain de. very large variations in the radiation reaching the semiconductor for very small displacements of the radioactive source.

It is understood that the devices described can be modified to allow all sorts of different applications. One of these could, for example, consist in measuring the radiation of a tree without exerting any friction on it. The radioactive source could be fixed to the shaft, while the semiconductor could be fixed and located close to this shaft. Thus, for each revolution of the shaft, an would obtain a current pulse in the electrical circuit received at the semiconductor. This application is in particular interesting for the measurement of the wind by means of a wind wheel, which must present practically no friction to allow an accurate measurement.

0n can of course use different semiconductors reacting to radioactive radiation. By way of example, one could use cadmium sulphide, cadmium tellurium or cadmium selenide. The absorbent gas could be helium or nitrogen. It is understood that the radioactive source could be fixed, the semiconductor then being movable with respect to the source.

Claims (4)

CLAIM Mechanical-electrical transformer, characterized in that it comprises a radioactive source adopts at least a part of the radiation reached a semiconductor adopts the electrical conductivity varies according to the radioactive radiation to which it is subjected , this semiconductor forming part of an electrical circuit, means being provided for varying, as a function of a mechanical quantity, the value of the radiation reaching the semiconductor, so as to generate a corresponding variation of the current in the first electrical circuit. SUB-CLAIMS 1. Transformer according to claim, characterized in that the radioactive source is arranged on a moving part relative to the semiconductor. 2. Transformer according to claim, characterized in that the radioactive source is placed on a membrane separated from the semiconductor by a gas absorbing the radioactive radiation. 3. Transformer according to claim and sub-claim 2, characterized in that the radioactive source consists of a film of radioactive material deposited on the membrane. 4. Transformer according to claim, characterized in that a mobile screen is interposed between the radioactive source RTI ID="0003.0271" WI="17" HE="3" LX="1409" LY="1554"> and the semiconductor.