Reader and transponder in enclosures

• US 20040099744A1
• Filed: 11/20/2003
• Published: 05/27/2004
• Est. Priority Date: 11/21/2002
• Status: Active Grant

• Current Assignee: Optosys SA
• Original Assignee: Optosys SA
• Inventors: Heimlicher, Peter, Cuperus, Johan
• Granted Patent: US 7,102,525 B2
• Time in Patent Office: Days
• US Class Current: 235/491
• CPC Class Codes: G06K 19/02 characterised by the selection of materials, e.g. to avoid wear during transport through the machine
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 19/07758 arrangements for adhering the record carrier to further objects or living beings, functioning as an identification tag
• CPC Class Codes: G06K 19/07771 the record carrier comprising means for minimising adverse effects on the data communication capability of the record carrier, e.g. minimising Eddy currents induced in a proximate metal or otherwise electromagnetically interfering object
• CPC Class Codes: G06K 7/089 hand-held scanners
• CPC Class Codes: G06K 7/10178 including auxiliary means for focusing, repeating or boosting the electromagnetic interrogation field comparable booster antennas integrated on the record carrier itself G06K19/07794
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: H01Q 1/42 Housings not intimately mechanically associated with radiating elements, e.g. radome
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Abstract

The antenna and the electronic control circuit of the transponder are contained in a totally hermetical metallic enclosure. The antenna of the reader is protected from the environment by a metallic front plate that is integral with the enclosure containing the electronic control circuit. In a preferred embodiment, the enclosure is hermetically tight. These embodiments fulfill the longstanding need to obtain completely tight elements that are resistant to industrial aggressions.

Claims

1. Transponder with an antenna and an electronic control circuit and comprising a metallic enclosure, wherein the antenna and the electronic control circuit are contained in a hermetical metallic enclosure.

4. Transponder or reader according to claim 1 or 2, wherein the enclosure is made of stainless steel with a wall thickness between 0.2 and 0.5 mm and the frequency of the carrier wave is comprised between 20 and 50 kHz.

5. Transponder or reader according to claim 1 or 2, wherein the antenna coils are rectangular in cross-section with the large side of the coil closely coupled to the metallic wall of the enclosure.

6. Transponder or reader according to claim 5, wherein an air gap is provided at the rear of said coils, opposite the enclosure or opposite the ferrite element.

7. Transponder and reader according to claim 1 or 2, wherein the resonance frequency of the antenna is 5 to 20% higher than that of the carrier.

8. Transponder and reader according to claim 1 or 2, wherein the Q factor of the resonant antenna is degraded in a controlled manner by a resistance.

2. Reader with an antenna and comprising an enclosure, wherein the antenna is protected from the environment by a metallic front plate that is integral with the enclosure containing the electronic control circuit.

3. Reader according to claim 2, wherein said enclosure comprises a hermetical closure.

9. Reader according to claim 2, wherein the reception circuit is preceded by a differentiating filter.