Beschrieben wird ein Beschleunigungsgrenzwertschalter mit einem kugelförmigen Trägheitskörper (6), der von einem Dauermagneten (5) gehalten wird. Bei einem Stoß über dem Grenzwert trifft der Trägheitskörper auf eine leitfähige Membran (3) und eine Leiterplatte (2) mit kammartig verzahnten Leiterbahnen.

Bei einem bekannten Schalter wird der Innenraum mit einem auf der Leiterplatte liegenden Deckel verschlossen, der Bohrungen zur Durchführung der Kontaktstifte aufweist. Zur Abdichtung hat der Deckel einen Kragen, der über einen O-Ring greift.

Die Ausführung zeichnet sich dadurch aus, daß der rotationssymmetrische Innenraum des SChalters (1e,1f) eine ringförmige Lagerfläche (1g1) für eine dünne Leitkunststoff-Matte (3) aufweist, daß die Leiterplatte (2) als Gehäusedeckel auf einem umlaufenden Gehäusesteg (1h) aufliegt, daß außerhalb dieses Steges (1h) ein Dichtungsring (4) liegt und daß die Leiterplatte (2) unter Deformation des Dichtungsringes (4) von gehäuseseitig angeformten, federnden Haken (1j,1k) gehalten ist.

An emergency inertial system for disconnecting the electric circuit of a vehicle from the electricity source or battery (2) in the event of impact, to prevent sparks being generated by impact-induced shortcircuiting and so safeguard against fire; the system presenting a 360° active inertial switch (10) in series with the electric circuit (3); and the inertial switch presenting a floating mass (20), first electric contact means (21) connected to opposite terminals of the electric circuit and separated by an insulating means, and second electric contact means (22) cooperating with the floating mass so as to switch from a first operating position wherein they shortcircuit the first electric contact means via the insulating means, and a second operating position wherein they are detached from the first electric contact means; the first electric contact means being defined by respective carbon brushes (21) of the type used for the sliding contacts supplying the rotors of electric motors.

An inertia device for interrupting the current supplied by a vehicle battery and in particular for interrupting the hot lines and those connected to the gasoline pump, comprising an inertia switch (2), a relay (3, 9), a movable contact (4) for connecting together a fixed input contact (6) and a fixed output contact (7). The input contact (6) comprises a first part (6A) shaped to secure and electrically connect the end of a cable (15) for connecting the device to the battery (26), and a second part (6B) integral with the first and arranged to cooperate with said movable contact (4), the input contact being an integral part of the internal electrical circuit of the device.

A helmet (20) has attached to its lower rim (32) an inflatable bag (40) which normally is folded so as not to restrict normal head and neck movements of the wearer but on inflation will fill the gap between the helmet rim and shoulders of a wearer. Carried by the helmet (20) and preferably packed with the bag (40) is a package (44) including a conventional gas generator, igniter and battery. A switch (46) to operate the igniter is located on the crown area of the exterior surface of the helmet (20) and is closable on an impact with a predetermined force on the crown of the helmet (20). When closed the bag (40) is almost instantaneously inflated and fills the gap to transfer most if not all of the impact force to the shoulders and relieve the cervical spine of a damaging axial compressive force. In another version, shoulder pads (112) are provided in which there is an attachment in the form of an inflatable bag (114) on the inner rim encircling the neck of the wearer. The inflatable bag (114) inflates upon the impact upon the crown area of the exterior surface of the helmet to extend inwards, just enough to instantaneously broaden the foundation on which the helmet attachment can rest when deployed upon impact without harming the wearer's neck.

A vehicle restraint system (20) that includes an impact sensor (22) coupled by fiber optics (50,64,66) to an igniter (26) for inflating an air bag (28). The impact sensor includes a permanent magnet (32) disposed within a cavity (34) and biased by magnetic force toward one end of the cavity, motion of the magnet in the cavity being sensed by a weigand wire (44) or Hall (86) sensor for igniting the air bag. Facility (72) is disposed externally of the cavity for selectively adjusting the bias of the sensor and/or moving the magnet into proximity with the Hall effect or weigand wire sensor to test operative condition of the sensor.

La présente invention concerne un capteur de chocs qui est capable de déclencher un signal d'alarme lors de l'apparition d'un choc venant d'une direction définie et en supprimant la production d'un signal d'alarme pour tout choc venant d'une direction autre que celles qui ont été définies.

Afin d'obtenir la sélection directionnelle d'un capteur de chocs, celui-ci comporte un moyen de contact ayant une partie fixe (2) en forme torique ou autre, et une partie mobile (3) qui est élastiquement suspendue au centre de la partie fixe (2) par un ensemble de suspension qui permet une élongation de la partie mobile (3) dans le sens parallèle au plan de la partie fixe (2) torique, uniquement lors de l'apparition d'un choc venant d'une direction parallèle au plan de la partie fixe (2) et supprimant tout mouvement aléatoire dans le sens parallèle à ce plan lors de l'apparition d'un choc agissant dans un sens perpendiculaire au plan de la partie fixe (2).

An acceleration sensor comprises a tube (14) formed of an electrically-conductive non-magnetic material; a magnetically-permeable element, such as a iron washer (32), proximate with the passage (24); and a sensing mass (34) in the passage (24) comprising a pair of permanent magnets (36) and a spacer (38) whose magnetic permeability increases with increasing temperature, with the magnets (36) being secured to the opposite sides of the spacer (38) so as to place a pair of like magnetic poles in opposition. In operation, the sensing mass (34) interacts with the iron washer (32) so as to be magnetically biased to a first position in the passage (24), while the magnetic-permeability of the spacer (38) and, hence, the magnetic flux generated by the sensing mass (34) adjusts to maintain a nearly constant threshold magnetic bias irrespective of variations in sensor temperature. The sensing mass (34) is displaced in response to acceleration of the housing (12) from its first position in the passage (24) towards a second position therein when such acceleration overcomes the threshold magnetic bias, while the tube (14) itself interacts with the sensing mass (34) to provide magnetic damping therefor. Upon reaching the second position in the tube (14), the sensing mass (34) electrically bridges a pair of contacts (60) to indicate that a threshold level of acceleration has been achieved. An electrical coil (70) is secured proximate with the iron washer (38) which, when energized, reversibly magnetizes the latter, whereby the sensing mass (34) is either repelled to the second position in the tube (14) or more strongly biased towards the first position therein.

An acceleration sensor comprises a tube (14) formed of an electrically-conductive, nonmagnetic material; an annular magnetically-permeable element (18), such as a iron washer, encircling a longitudinal portion of the tube (14); a magnetic sensing mass (32) in the tube which magnetically interacts with the washer (18) so as to be magnetically biased towards a first or "rest" position in the tube (14) characterized in that a longitudinal portion of the sensing mass (32) is situated within the portion of the tube (14) encircled by the washer (18), the sensing mass (32) being displaced from its rest position in the tube (14) towards a second position therein in response to an accelerating force exceeding the magnetic bias thereon; and a switch (28) operated by the sensing mass (32) when the sensing mass is displaced to its second position in the tube (14). The instant accelerometer features a low threshold magnetic bias of the sensing mass to provide a quickened sensing mass response to acceleration inputs of short duration; and a magnetic bias which increases in a substantially linear manner with increasing sensing mass displacement from its rest position towards its second position within the tube (14).

An acceleration sensor comprises a housing having a magnetically permeable element, such as a steel washer, secured thereto proximate with an end of a cylindrical passage formed therein; a magnetic sensing mass in the passage which is displaced in response to acceleration of the housing from an initial position within the passage proximate the steel washer to a second position within the passage when such acceleration overcomes the magnetic bias of the sensing mass towards the steel washer;

and a pair of beam contacts projecting from the housing into the passage so as to be bridged by the sensing mass when the sensing mass is displaced to the second position within the passage. The accelerometer further comprises a pair of oppositely-wound electrical coils encompassing the passage proximate the initial position and the second position of the sensing mass therein, respectively. Upon the delivery of a direct current to the coils, the sensing mass is magnetically biased to the second position within the passage, whereby the beam contacts are bridged by the sensing mass to confirm the operability of the sensor.

An acceleration sensor comprises a housing having a magnetically permeable element, such as a steel washer, secured thereto proximate with an end of a cylindrical passage formed therein; a magnetic sensing mass in the passage which is displaced in response to acceleration of the housing from an initial position within the passage proximate the steel washer to a second position within the passage when such acceleration overcomes the magnetic bias of the sensing mass towards the steel washer;

and a pair of beam contacts projecting from the housing into the passage so as to be bridged by the sensing mass when the sensing mass is displaced to the second position within the passage. The accelerometer further comprises a pair of oppositely-wound electrical coils encompassing the passage proximate the initial position and the second position of the sensing mass therein, respectively. Upon the delivery of a direct current to the coils, the sensing mass is magnetically biased to the second position within the passage, whereby the beam contacts are bridged by the sensing mass to confirm the operability of the sensor.

An acceleration sensor (10) comprises a tube (14) formed of an electrically-conductive non-magnetic material; a stop (30) defining an end of the tube which moves longitudinally thereof in response to temperature; a magnetically-permeable element, such as a iron washer (44), proximate with the end of the tube (14); and a sensing mass (46) in the tube (14) comprising a pair of permanent magnets (48) secured to the opposite sides of an iron spacer (50) so as to place a pair of like magnetic poles thereof in opposition. In operation, the sensing mass (46) interacts with the iron washer (44) so as to be magnetically biased against the stop (30), while the stop (30) moves longitudinally of the tube (14) to maintain a nearly constant threshold magnetic bias on the sensing mass (46) irrespective of variations in sensor temperature. The sensing mass (46) is displaced in response to acceleration of the housing (12) from its first position against the stop (30) towards a second position in the tube (14) when such acceleration overcomes the magnetic bias, while the tube (14) itself interacts with the sensing mass to provide magnetic damping therefor. Upon reaching the second position in the tube 14 , the sensing mass (46) bridges a pair of electrical contacts (54) with an electrically-conductive surface (56) thereof to indicate that a threshold level of acceleration has been achieved. An electrical coil (60) is secured proximate with the iron washer (44) which, when energized, reversibly magnetizes the latter, whereby the sensing mass (46) is either repelled to the second position in the tube or more strongly biased against the stop (30).