MOUNTING AN RFID TAG ON A SUPPORT FORMED OF A MATERIAL WHICH BLOCKS OR ATTENUATES RF SIGNALS

FIXATION D'UNE ETIQUETTE D'IDENTIFICATION PAR RADIOFREQUENCE SUR UN SUPPORT FORME D'UN MATERIAU QUI BLOQUE OU ATTENUE LES SIGNAUX RF

English Abstract

An RFID tag for attachment to a supporting material comprising a generally flat strip is adhesively mounted inside the base of a rectangular container having side walls and end walls extending generally to an open upper edge of the box where the open upper edge is arranged to be fastened to the material so that the tag thus is supported by the base at a position spaced from the material by a distance defined by a spacing of the base from the upper edge.

French Abstract

Une étiquette RFID à attacher à un matériau de support comprenant une lanière généralement plate est installée par adhésif dans la base dun contenant rectangulaire ayant des parois latérales et des parois dextrémité sétendant généralement vers un bord supérieur ouvert de la boîte, ce bord étant configuré pour être attaché au matériau, de sorte que létiquette soit supportée par la base à une position espacée du matériau par une distance définie par un espace de la base par rapport au bord supérieur.

Claims

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CLAIMS:
1. An RFID tag apparatus for mounting on a material which is blocking
or attenuating to RF signals comprising:
an RFID tag in the form of a strip;
a container box for containing the tag;
the container box having a base, side walls and end walls upstanding from
the base to an open upper edge of the box;
the base being dimensioned to receive the strip forming the tag lying on the
base;
an adhesive material bonding the tag to the base;
the open upper edge being arranged to be fastened to the material;
the tag thus being supported by the base at a position spaced from the
material by a distance defined by a spacing of the base from the upper edge.
2. The apparatus according to claim 1 wherein the box is open at the
open upper edge so that the open upper edge is defined by a top edge of the
side walls
and end walls.
3. The apparatus according to claim 1 or 2 wherein the RFID tag is
affixed to the base by a wet inlay.
4. The apparatus according to any one of claims 1 to 3 wherein the
RFID tag is affixed to the base by pressure sensitive adhesive.
5. The apparatus according to any one of claims 1 to 4 wherein the tag
is covered with calking to make the tag waterproof.
Date Recue/Date Received 2021-02-19

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6. The apparatus according to any one of claims 1 to 5 wherein the
open upper edge includes at least a pair of opposed wings for fastening to the
material.
7. The apparatus according to claim 6 wherein the opposed wings
extend outwardly from the open upper edge.
8. The apparatus according to any one of claims 1 to 7 wherein the box
is arranged to be installed using adhesive between the upper edge and the
material.
9. The apparatus according to any one of claims 1 to 7 wherein the box
is arranged to be installed using double face tape between the upper edge and
the
material.
10. The apparatus according to any one of claims 1 to 9 wherein the box
includes an opening allowing escape of moisture.
11. The apparatus according to claim 10 wherein the opening is defined
at the open upper edge.
12. The apparatus according to claim 10 wherein the opening is defined
by a recess at the open upper edge of at least one of the side and end walls.
13. The apparatus according to claim 12 wherein both side walls are
recessed so as to define a slot along the open upper edge at each side wall.
14. An article carrying an RFID tag wherein the article includes a wall
formed of a material which is blocking or attenuating to RF signals and an
apparatus
according to any one of claims 1 to 13 where the box is mounted on the wall.
Date Recue/Date Received 2021-02-19

Description

CA 02873221 2014-12-02
MOUNTING AN RFID TAG ON A SUPPORT FORMED OF A MATERIAL WHICH
BLOCKS OR ATTENUATES RF SIGNALS
This invention relates to an arrangement for mounting an RFID tag on
a support formed of a material which blocks or attenuates RF signals.
BACKGROUND OF THE INVENTION
The present invention generally relates to the tracking of containers or
other similar objects, and more particularly to apparatus and techniques for
attaching
a radio frequency identification (RFID) tag to an article where the support on
which
the tag is mounted is formed of a material which blocks or attenuates RF
signals.
There is a widespread need to track and identify a variety of items in
the normal course of business operations. For example, in a company's supply
chain, the capability to readily identify and track items can decrease the
time to
market, increase efficiency, decrease costs, and provide a host of other
advantages.
In addition in waste material collection, tracking the location of
containers using RFID tags can significantly increase the efficiency of the
system
and can provide an input to a control system which monitors and tracks the
containers which are unloaded.
One solution to such a need is an RFID tag tracking system in which
an RF1D tag is attached to each of the items to be tracked. A typical passive
RFID
tag tracking system comprises the RFID tags and an interrogator, also known as
a
reader. The RFID tag includes an antenna and a microchip, which may store data
such as a serial number or an item identification number. To read the data
stored on

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the microchip, the interrogator transmits electromagnetic radio frequency (RF)
waves to the RFID tag. The antenna of the RFID tag receives these broadcast
electromagnetic RF waves and the small electrical current induced in the
antenna is
used to power the microchip. The RFID tag is powered by the received RF waves
allowing it to send data, such as the serial number, to the interrogator
through RF
waves.
Unlike a bar code read by an optical scanner, an RFD tag tracking
system does not depend upon an unobstructed line of sight from the reader to
the
item to be read since RF signals pass through many types of materials.
However,
RF signals can be blocked or interfered with by some types of materials, such
as
metals and liquids. These materials, which may be used to construct the
article to be
tracked, may prevent reliable communication between the interrogator and the
RFID
tag attached to a side of the package by blocking or substantially
attenuating.
Therefore, it would be advantageous to provide systems and methods
for attaching an RFID tag to an article which allows the RFID tag to be read
when
the article contains or is manufactured from an RF blocking, or attenuating
material.
That is, standard UHF RFID tags cannot be read when mounted directly on metal
or
any other dense material.
Some manufacturers have invented multi layers RFD tags that include
a reflective layer separated from the antenna layer by a dielectric with a
known
impedance. These tags have the disadvantage of being expensive.

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SUMMARY OF THE INVENTION
According to the invention there is provided an RFID tag apparatus for
mounting on a material which is blocking or attenuating to RF signals
comprising:
an RFID tag in the form of a generally flat strip;
a container box for containing the tag;
the container box having a base, side walls and end walls extending
generally at a right angle to the base to an open upper edge of the box;
the base being dimensioned to receive the flat strip forming the tag
lying flat on the base;
an adhesive material bonding the tag to the base;
the open upper edge being arranged to be fastened to the material;
the tag thus being supported by the base at a position spaced from the
material by a distance defined by a spacing of the base from the upper edge.
Preferably the box is open at the open upper edge so that the open
upper edge is defined by a top edge of the side walls and end walls.
Preferably the RFID tag is affixed to the base by a wet inlay.
Preferably the RFID tag is affixed to the base by pressure sensitive
adhesive.
Preferably the tag is covered with calking to make the tag waterproof.
Preferably the open upper edge includes at least a pair of opposed
wings for fastening to the material.

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Preferably the opposed wings extend outwardly from the open upper
edge.
Preferably each wing has a hole that will be used to install the tag on
the steel (or dense) surface by using rivets or screws.
Preferably the box is arranged to be installed using adhesive between
the upper edge and the material.
Preferably the box is arranged to be installed using double face tape
between the upper edge and the material.
Preferably the box includes an opening allowing escape of moisture.
Preferably the opening is defined at the upper edge.
Preferably the opening is defined by a recess at the upper edge of at
least one of the side and end walls.
Preferably both side walls are recessed so as to define a slot along the
upper edge of each side wall.
Preferably the article includes a wall farmed of a material which is
blocking or attenuating to RF signals and an apparatus according to any
preceding
claim where the box is mounted on the wall.
Thus the present invention provides a tag that works very well on metal
or other dense surfaces. This tag is made of standard pressure sensitive
inlays
(called wet inlays) mounted in a special plastic box. These inlays as well as
the
plastic boxes are inexpensive. This invention is based on the fact that the
reading
distance increase logarithmically with the distance separating the inlay from
the

CA 02873221 2014-12-02
dense surface. By creating a gap of 1 or 2 centimeters, the reading distance
goes
from Om to 5m.
BRIEF DESCRIPTION OF THE DRAWINGS
One embodiment of the invention will now be described in conjunction
5 with the accompanying drawings in which:
Figure 1 is a cross-sectional view through a door, door lock and
security device according to the present invention.
Figure 2 is an exploded view of the components of Figure 1
In the drawings like characters of reference indicate corresponding
parts in the different figures.
DETAILED DESCRIPTION
As shown in the Figures, a standard UHF RFID wet inlay or pressure
sensitive (label type) RFID tag 10 is attached by adhesive layer 11 such as a
weet
inlay or pressure sensitive adhesive on the bottom face of a box 12. The box
has
one end 13 open which is opposed to the surface or base 14 where the inlay
including the tag and adhesive layer is applied. Some caulking 15 partly or
wholly
filling the box can be used to make the tag waterproof. The box has a wing 16
on
each side of the open end 13 attached to the top edge of one of the end walls
17.
Each wing 16 has a hole 16A that will be used to install the tag 10 on the
steel (or
dense) surface 20 by using rivets or screws. The box can also be installed
using
some type of glue or double face tape applied on the top edge of the open end
at the
to edge of the end walls 17 and side walls 18.

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The box includes an opening allowing escape of moisture where the
opening is defined at the upper edge and the opening is defined by a recess 19
at or
along the upper edge of at least one and preferably both of the side walls 18
so that
the moisture can depart the box when the box is in different orientations such
as with
the base at the top or the base vertical.

Representative Drawing