| 摘要 |
1,209,506. Vehicle detectors; counters. MARCONI CO. Ltd. 12 Nov., 1968 [18 March, 1968], No. 12968/68. Headings G4D and G4Q. [Also in Division G1] A vibration detector such as for vehicle detectors, comprises a tubular outer conductor 1 and an inner conductor 2 so arranged that they do not have a common longitudinal axis, insulating solid dielectric material 3 between the conductors and means for mounting the conductors so as to subject them to vibration to generate a voltage as a result of contact disturbance between the material 3 and at least one of the conductors 1, 2. The detector 1-3 may be embedded in rubber 12, which is secured by adhesive 14 to the rod 13. A conductive tube 1 is attached to a metal plate 11 so that vibrations due to vehicles generate voltage impulses in leads LL for connection to a detecting amplifying and utilization device AU which may be a transistor amplifier (Fig. 4 of Provisional Specification, not shown). The output from the detector 1-3 may be used to control traffic signals or count the vehicles. The detector 1-3 may be mounted in a segment section rubber strip (Fig. 2 of Provisional Specification, not shown), mounted above, below or flush with the road surface. Alternatively, the detector 1-3 may be mounted in a tubular portion (6) of an extruded aluminium strip (Fig. 3 of Provisional Specification, not shown), or the tubular portion (6) of which may replace the conductor 1. The inner conductor 2 and insulation 3 may be the inner part of a flexible H.F. cable. Also a coaxial cable having an inner conductor surrounded by a dielectric layer and a further braided outer conductor and outer sheath may be placed in a metal tube. The end remote from the connections LL may be closed. Known vehicle detectors listed by the Specification are piezo-electric crystal and a capacitor having the spacing between its plates altered. |
