A system useful in service stations and the like for indicating the entry of a vehicle onto a specified area of the earth's surface. The system includes a magnetic field sensor which yields an output signal indicative of the magnetic field intensity thereat. The sensor is mounted adjacent to but outside of a volume being monitored which constitutes the projection of the specified area in the direction of the magnetic field thereat. When the magnetically permeable mass of a vehicle enters the volume being monitored, it increases magnetic field intensity therein but reduces the field intensity outside of this volume. The reduction in field intensity is recognized by the sensor which then energizes an indicating device such as a remote bell. The sensor preferably comprises a flux gate magnetometer which is excited by a high frequency signal supplied by an oscillator. This signal can be coupled to the existing service station power line to energize the remotely located bell, also coupled to the power line.
A system useful for indicating the entry of a vehicle onto a specified area of the earth's surface. The system includes a magnetic field sensor which yields an output signal indicative of the magnetic field intensity thereat. The sensor is mounted adjacent to but outside of a volume being monitored which constitutes the projection of the specified area in the direction of the magnetic field thereat. When the magnetically permeable mass of a vehicle enters the volume being monitored, it increases magnetic field intensity therein but reduces the field intensity outside of this volume. The reduction in field intensity is recognized by the sensor which then energizes an indicating device, which in the case of a service station installation, for example, can be a remote bell. The sensor preferably comprises a flux gate magnetometer mounted within a thin substantially rigid housing dimensioned to fit within a slot formed by saw cutting a roadway surface.
A device for detecting mobile ferromagnetic masses, notably of vehicles, comprising a magnetometric pick-up element of the type with orthogonal fields. The pick-up element is a ferrite tube of small dimensions which is provided with a toroidal pump winding and a solenoid signal winding. The output of the processing and amplifying device for the signal of the pick-up element is fed back to the solenoid winding via a circuit comprising a low-pass filter and a symmetrical current amplifier. A pulseshaper for the amplified signal supplied by the pick-up element comprises phase-shifting circuits, so that a single squarewave pulse can be obtained upon the passage of a metallic mass.
An automation system for train maintenance that performs operations related to train maintenance without human intervention is provided. The automation system for train maintenance comprises a refuse reservoir (10), a sewage tank (20), a water tank (30), and expanders (41, 42, 51, 61). In this automation system, when a railway vehicle is parked, the expanders (41, 42, 51, 61) are expanded to lift connectors (45, 54, 64) toward the railway vehicle for connection to the refuse reservoir (10), sewage tank (20), and water tank (30). In this automation system, discharge of refuse, removal of sewage, and feeding of water are automatically performed. Upon completion of these operations, the expanders (41, 42, 51, 61) are contracted so that the connectors (44, 45, 54, 55, 64, 65) are stored in waiting locations (48, 58). Therefore, use of this automation system for train maintenance allows automatic train maintenance without human intervention.
An underground vehicle sensing system extends below a vehicle travel surface to detect the presence of a vehicle. A conduit extends substantially horizontally underground from an access hole placed at the side of the vehicle travel surface. A plurality of sensors are spaced apart in the conduit to detect localized changes in the magnetic field. A plurality of sections house the probes and wiring to orient and position the probes. Sections detachably clip together to form a lightweight support structure and may be added one by one through the access hole. Lightweight extension members are utilized in some configurations between the support sections for positioning and supporting the probes.
A reusable mechanical fastening means for a vehicle monitoring system facilitates maintenance and repair of the system. A plurality of carrier sections are connected together by clips. The clips have release tabs to move prongs against a spring force, thereby making the clips manually detachable. Vehicle sensing probes have interference ridges which mate with probe openings in the carrier sections. The carrier sections have open bottoms, and the worker can overcome the locking force of the interference ridge by turning the carrier section over and pressing on the probe through the open bottom. The clips can be attached on multiple planes relative to the carrier sections, minimizing torsional play within the extended support train. The clips and carrier sections are also easily manufacturable.
