Magnetic marker and magnetic marker system
AssigneeAichi Steel Corporation
InventorsMichiharu Yamamoto, Tomohiko Nagao, Hitoshi Aoyama, Koei Gemba
Life of this patent
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Abstract
In a columnar-shaped magnetic marker including a magnet formed by dispersing a magnetic powder of iron oxide in a polymer material and to be laid in a road without being accommodated in a metal container, one end face of an outer peripheral surface and an entire outer peripheral side surface of magnet are covered with metal foil forming a conductive layer, and an RFID tag which performs wireless communication with a tag reader mounted on a vehicle side is arranged on the end face of magnetic marker provided with metal foil as being in a state of being electrically insulated from metal foil.
Claims17
A magnetic marker to be laid in a road, the magnetic marker comprising:
- a wireless tag including a circuit which processes information transmitted and received by wireless communication and a first antenna provided to extend electrically from the circuit, and
- a conductive layer provided on at least part of an outer peripheral surface of a main body forming a magnetism generation source, the conductive layer being not electrically continuous with the main body, wherein
- the wireless tag includes a second antenna which relays electric waves transmitted and received by the first antenna, and the second antenna makes electrical contact with the conductive layer, and
- the second antenna has a U-shaped cross section, and the first antenna is provided so as to be positioned on an inner periphery of the second antenna having the U-shaped cross section.
A magnetic marker system comprising a magnetic marker laid in a road, wherein
- the magnetic marker includes a wireless tag including a circuit which processes information transmitted and received by wireless communication and a first antenna provided to extend electrically from the circuit, and a conductive layer provided on at least part of an outer peripheral surface of a main body forming a magnetism generation source, the conductive layer being not electrically continuous with the main body, and
- a buried section where magnetic markers are buried and a road-surface arrangement section where magnetic markers are arranged on the road surface are set to the road,
- the magnet marker system comprising:
- a reader device mounted on a vehicle to supply electric power to the wireless tag by wireless communication and read information transmitted from the wireless tag by wireless communication, wherein
- the reader device has a frequency switching part which selectively sets any of a plurality types of carrier frequencies for transmitting the electric power by wireless communication, and switches the carrier frequency for transmitting the electric power by wireless communication according to whether the vehicle travels in the buried section or the road-surface arrangement section.
A magnetic marker system comprising a magnetic marker laid in a road, wherein
- the magnetic marker includes a wireless tag including a circuit which processes information transmitted and received by wireless communication and a first antenna provided to extend electrically from the circuit, and
- a conductive layer provided on at least part of an outer peripheral surface of a main body forming a magnetism generation source, the conductive layer being not electrically continuous with the main body,
- the wireless tag includes a second antenna which relays electric waves transmitted and received by the first antenna, and the second antenna makes electrical contact with the conductive layer, and
- the second antenna has a U-shaped cross section, and the first antenna is provided so as to be positioned on an inner periphery of the second antenna having the U-shaped cross section.
Dependencies are inferred from the claim text.