Apparatus for transmitting distress signals

• US 3,990,040 A
• Filed: 10/21/1974
• Issued: 11/02/1976
• Est. Priority Date: 10/23/1973
• Status: Expired due to Term

• Current Assignee: Thomson-CSF (Thales SA)
• Original Assignee: Thomson-CSF (Thales SA)
• Inventors: Billottet, Henri, Narbaits-Jaureguy, Jean-Raymond, Gleitz, Jean-Jacques
• Primary Examiner(s): Waring, Alvin H.
• Application Number:
  US05/516,574
• Time in Patent Office: 743 Days
• Field of Search: 340/52 R, 340/52 F, 340/52 H, 340/53, 340/61, 340/262, 340/65, 325/111, 325/112, 325/114, 325/117
• US Class Current: 340/436
• CPC Class Codes: B60Q 1/445 controlled by inertial devices
• CPC Class Codes: B60Q 1/52 for indicating emergencies

Abstract

A distress-signal generator aboard a vehicle includes a transmitter with a self-locking relay for energizing a high-frequency oscillator from a local battery in response to one or more trigger signals from respective detectors, specifically an impact detector and a deformation detector. The impact detector comprises two coacting members, one of them fixed to the vehicle body and the other freely movable with reference thereto, the elastically suspended mobile member being generally spool-shaped and having its waist received in an oblong opening of the plate-shaped fixed member. With the major axis of the oblong extending in the direction of vehicle motion, contact between the two members occurs in response to relatively small transverse and vertical accelerations but only with relatively large longitudinal acceleration; relative torsion is detected by a horizontal pin on the mobile member bracketed by two stops on the fixed member normally spaced therefrom. The deformation detector includes a bent wire with a rigid but rupturable sheath conforming to the shape of the vehicle body at critical locations. The transmitter comprises a multivibrator tuned to an audio frequency and energized in parallel with the oscillator by the relay, this multivibrator working through an RC circuit into the base of a transistor forming part of the oscillator so as to apply to it a sawtooth signal modulating the generated high-frequency oscillation in both amplitude and frequency, the modulated oscillation being sent out via an antenna coupled with the tank circuit of the oscillator.

Claims

1. A distress-signal generator carried aboard a moving object, comprising:

a deformation detector including an elongate rupturable conductor clad in a substantially rigid sheath of breakable insulating material, said conductor substantially conforming to the shape of the body of said object and contacting said body at a plurality of critical locations, and circuit means connected to said conductor for signaling any interruption thereof; and

transmitting means connected to said circuit means for emitting a distress signal upon an interruption of said conductor;

said circuit means including a lead protected against rupture and connected in parallel with said conductor to a source of operating voltage, and gate means with inputs respectively connected to said source via said conductor and said lead for generating an output signal triggering said transmitting means upon de-energization of one of said inputs by rupture of said conductor.

2. A distress-signal generator carried aboard a moving object, comprising:

a deformation detector including an elongate rupturable conductor substantially conforming to the shape of the body of said object and contacting said body at a plurality of critical locations;

a lead protected against rupture and connected in parallel with said conductor to a source of operating voltage;

a NAND gate with inputs respectively connected to said lead and to said conductor, said NAND gate having an output delivering a trigger signals upon rupture of said conductor due to a significant shape change of said body at any of said critical locations; and

transmitting means connected to said output for emitting a distress signal in response to said trigger signal.

3. A distress-signal generator as defined in claim 44 wherein said conductor comprises a frangible wire clad in a substantially rigid sheath of breakable material.

4. A distress-signal generator as defined in claim 21 wherein said breakable material is a cured thermosetting resin.

5. A distress-signal generator carried aboard a surface vehicle, comprising:

sensing means for producing a trigger signal in response to an abnormal condition of said vehicle, said sensing means including an impact detector with a fixed member secured to the vehicle body and a mobile member displaceable relatively thereto against a restraining force, one of said members having an oblong horizontal opening receiving the other of said members with clearance, the major axis of said opening extending in the direction of vehicle motion whereby a substantially greater acceleration of the vehicle in said direction of motion is required than in a direction transverse thereto for establishing contact between said members at the edge of said opening, said members being provided with circuitry for delivering said trigger signal upon the establishment of said contact; and

transmitting means connected to said sensing means for emitting a distress signal in response to said trigger signal;

said fixed member being a horizontal plate provided with said opening, said mobile member being generally spool-shaped with a vertical axis and with a waist in the plane of said plate, and mobile member being provided with elastic suspension means engaging same along said vertical axis and providing said restraining force, said mobile member having upper and lower flanges respectively overlying and underlying the lateral edges of said opening for contacting said plate in response to a sharp vertical acceleration.

7. A distress-signal generator as defined in claim 5 wherein said sensing means further includes a deformation detector contacting the vehicle body at a plurality of critical locations, said transmitting means comprising a relay energizable by a trigger signal from either of said detectors and provided with holding means for maintaining itself energized.

6. A distress-signal generator as defined in claim 25 wherein said elastic suspension means comprises a pair of torsion springs resisting relative rotation of said mobile member and said plate, said mobile member being provided with a substantially horizontal projection, said plate being provided by a pair of stops normally spaced from said projection and engageable thereby upon relative rotation of said members in a respective direction for producing said trigger signals upon such engagement.