Abstract: A resettable, latching indicator is described. The indicator has a pair of electrical terminals through which it connects to the circuitry whose state is being indicated. The device includes an electromagnetic coil with a first lead connected to a first terminal of the device and a second lead connected to a first contact within the device. A second contact within the device is connected to the second indicator terminal, completing the circuit within the device. In a preferred embodiment, the device is arranged as a fuse state indicator with the device terminals connected in parallel with a fuse. Before fuse blow, an internal electrical contact is formed as the first and second contacts are closed an abutment formed on a spring-biased indicator flag. When the fuse blows, current passes through the coil, thus creating a magnetic field. The field moves a spring-biased armature having a catch which normally retains the indicator flag in a non-indicating position.

Abstract: An elapsed time hour meter for measuring and indicating an amount of elapsed time used in many types of applications. The elapsed time hour meter has a cylindrical rotating counter indicator that indicates the amount of elapsed time, and it is driven by an electrically powered watch movement. The gear work of the elapsed time hour meter couples the watch movement to the rotating counter whereby the watch movement drives the counter indicator to measure and indicate the actual amount of elapsed time. The watch movement is a reliable production wrist watch without battery, face and hands and to the minute stem of which is affixed a minute gear coupled to an intermediate gear supported on a lower housing half which couples to the counter indicator. The power supply elements and external terminals are supported in the upper housing half. The elapsed time hour meter is versatile and reliable and has the advantages of being small in size, low in cost, and low in power consumption.

Abstract: A stepping motor (44) for use in and in combination with an elapsed time indicator (10) of the type including a plurality of indicator drums (102, 104, 106 and 108) and a drive train (FIG. 3) driven by the motor for driving the indicator drum (102). The motor includes a rotor (56) and a stator providing a pair of stator poles (50, 52) including a notch (94, 96) in respective poles faces. The notch creates a pair of pole faces, one of major length and the other of minor length in each stator pole. In a non-current condition, the rotor seeks a dwell or detent position rotationally toward the pole face of greater concentration of iron. When the winding (54) is pulsed, the rotor, within at least the second pulse, moves unidirectionally and between pulses locates a further dwell or detent position. An indicator (154) including a flag (156) is controlled in movement by the motor so that the flag is moved into and out of a viewing window (40) to indicate motor operation.

Abstract: A sensing apparatus is responsive to the relative velocity of a vehicle and an impacted object in a crash environment to provide an output when a predetermined pressure is developed in a sensing chamber resulting in deployment of an air bag within the vehicle compartment. The purpose of the air bag is to restrain movement of the occupant relative to the vehicle in the event of a "high speed" crash. The sensing apparatus utilizes in operation the characteristics of flow of a fluid through an orifice. The sensing apparatus includes a sealed chamber formed by a cylinder and an expandable reservoir for receiving the fluid and absorbing surges as the fluid flows through the orifice. A piston movable in the cylinder against a biasing force imparts movement to the fluid thereby to attain some velocity of flow.