Patent GB-190611021-A (GB)
Title: Improved Method of and Means for Signalling or Effecting Operations by Means of Sound or other Vibrations.
Inventor: GARDNER JOHN
Filed: 1906-05-11
Granted: 1907-03-28
Abstract: 11,021. Gardner, J. May 11. Sound, controlling and actuating apparatus by ; signals, marine and ship.-Relates to receiving- apparatus for submarine sound-signalling, as in communicating with a ship from a lighthouse or lightship, and for-controlling apparatus such as torpedoes, electric switches, &c. by means of sound. The sound is received by a microphone, which may be directly connected to an electro-magnetic device for giving the desired signal, or effecting the desired control, but is preferably arranged in circuit with a telephone receiver or electro-magnet having a tuned diaphragm or reed which carries one electrode of a second microphone controlling the said electro-magnetic device. In the latter case, the strip or reed only responds to sounds of a certain note. The electro-magnetic device is so arranged in circuit with the microphone-that it is actuated upon an increase in the microphone resistance, and consequent reduction of current in the circuit. The receiving-microphone may also be mounted on a tuned box, air column, reed, &c., so that it only responds to certain sounds. Fig. 1 shows the application of the invention to controlling the motion and firing of a torpedo. The receiving-microphone A is in circuit with the primary of an induction coil D, the secondary circuit of which includes a telephone receiver E, having a tuned diaphragm F carrying one electrode G of a second microphone, arranged in circuit with a high-resistance relay N. Sound vibrations of the frequency to which the diaphragm F is tuned vibrate the latter and increase the resistance of the microphone G, thus de-energizing the relay, which controls an electro-magnetic time-switch such as is described in Specification No. 20,496, A.D. 1904, [Abridgment Class Electricity, Regulating &c.]. When the relay is de-energized, its tongue rests against a contact M, completing the circuit of a magnet P<3>, which allows the slowly rotating disk P<2> to move the contact-arm R over the contacts T, T<1>, T<2>, T<3> The first movement of the arm R closes the circuit of the propelling-motor S of the torpedo, and as the contact T is longer than the other contact this circuit remains closed when the arm R passes over the contacts T<1>, T<2>, T<3>, closing in succession the circuits of the devices S<1>, S<2>, s<3>, which may respectively operate the rudder to port, and to starboard, and fire the charge. When the sounds cease, the relay N is again energized, completing the circuit of the magnet P', which allows the disk P<2> to return the arm R'to its initial position. In a modification, the microphone A is mounted on a tuned reed, and is included directly in the circuit of the magnet P', the magnet P<3> being replaced by a permanent magnet, and the relay N dispensed with. Fig. 3 shows an arrangement by which the magnets P<1>, p<3> may be moved laterally over the rotating disk p<2>, so as to vary the ratio of advance and return of the arm R. For this purpose the slotted end of the bar Q engages one or other of the pins 1, 2, 3, 4, 5. Any other time-switch may be substituted for that shown. Fig. 5 shows the construction of the preferred form of telephone receiver E, used in the arrangement shown in Fig. 1.. The usual circular diaphragm is replaced by a flat strip F carrying one electrode of the microphone.. One end of the strip is fixed to the pivoted lever 8 so that its natural period of vibration may be varied by means of the adjusting- screw 7. The magnet is mounted on a stiff spring 9 in such a way that the distance between the strip F and the magnet poles can be adjusted by means of the screw 10. A reed supported at one end only may replace the strip F.. Several receiving-microphones associated with resonators tuned to different notes may be arranged to control a number of separate local circuits. These microphones may directly receive the sounds, or may be operated by separate microphones and receivers as shown in Fig. 1. Or one receiving-microphone may have all the telephonic microphone vibrators in circuit with it. The electro-magnetic device included in the receiving-microphone circuit may have an ordinary diaphragm or a tuned strip and the vibration of this strip may itself give the desired signal, or a lightly balanced lever may rest on the diaphragm in such a way that when the diaphragm vibrates, the lever may intermittently close a local circuit. The "chattering" of the lever may itself be the signal. The receiving- microphones may be mounted on felt so as not to respond to local vibrations. The Provisional Specification refers to the use of two or more circuit-closing devices, each operated from a separate microphone, and arranged in series in such a way that the local circuit is only closed when both or all the devices are rendered operative by simultaneously sounding all the notes to which the individual devices-are, respectively, resonant.