U.S. patent number 3,862,399 [Application Number 05/350,818] was granted by the patent office on 1975-01-21 for card reading method and apparatus.
Invention is credited to Jack C. Cain.
| United States Patent |
3,862,399 |
| Cain |
January 21, 1975 |
CARD READING METHOD AND APPARATUS
Abstract
A card having spots of paramagnetic material is inserted in a
pocket in a card reader. At one side of the pocket opposite each of
the spots is a magnet and at the other side is a reed switch. The
magnetic material in the card acts as a shunt for the magnetic
field of the magnet. In one embodiment it prevents that magnetic
field from reaching the switch in sufficient strength to operate
the switch. In another embodiment it increases the magnetic field
to the switch by providing a paramagnetic path to the switch, with
the switch being open in the absence of that path. In another
embodiment it interferes with a repulsion between two magnets on
opposite sides of the card so that the magnet on the side adjacent
the switch moves toward the card and away from the switch to
thereby open the switch contact.
|
Inventors: |
Cain; Jack C. (Arlington
Heights, IL) |
| Family
ID: |
23378326 |
| Appl.
No.: |
05/350,818 |
| Filed: |
April 13, 1973 |
| Current U.S.
Class: |
235/450; 200/46;
235/493; 365/97; 235/488; 365/62 |
| Current CPC
Class: |
G06K
7/088 (20130101) |
| Current International
Class: |
G06K
7/08 (20060101); G06k 019/06 (); G06k 007/08 ();
H01h 043/08 () |
| Field of
Search: |
;235/61.11D,61.12M
;200/46 ;340/174PM |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Cook; Daryl W.
Attorney, Agent or Firm: Darbo, Robertson &
Vandenburgh
Claims
I claim:
1. In the combination of a card and a card reading device, the
improvement comprising:
said device defining a way for receiving said card, said device
including a reed switch positioned at one side of said way, said
reed switch being closed when a magnetic field of a relatively
strong strength condition is applied thereto and being open when a
relatively weak magnetic field strength condition is applied
thereto, said device including magnet means including a magnet
mounted on the opposite side of said way, said card being
positioned at a given location in said way, being mainly
non-magnetic material and including magnetic material means of
inconsequential residual magnetism, said magnetic material means
being positioned between the magnet and the switch and intercepting
the magnetic lines of force emanating from said magnet so that said
magnetic means applies a magnetic field of one of said conditions
to said reed switch, said card being removable from said way
whereby said magnetic material means no longer intercepts the lines
of force from said magnet and said magnetic means applies a
magnetic field of the other of said conditions to said reed
switch.
2. In the combination set forth in claim 1, wherein said reed
switch and said magnetic means form a pair with which said magnetic
material means cooperates as described, said device including a
plurality of said pairs, said card including a plurality of said
magnetic material means positioned at different locations on the
card to correspondingly cooperate with a respective pair.
3. In the combination of claim 2, wherein said magnetic material
means is obscured from visual examination of the exterior of said
card.
4. In the combination of claim 2, wherein said device and said card
include means restricting the insertion of said card into said way
to said location to a single orientation of said card.
5. In the combination of claim 2, wherein said device includes
detecting means connected to said switches to determine which of
the switches are open and which are closed.
6. In the combination of claim 1, wherein said magnet is positioned
to hold said reed switch closed in the absence of said card, when
said card is in said position said magnetic material means shunting
the magnetic field from said magnet whereby said switch then is
open.
7. In the combination of claim 6, wherein said device includes
sensing means connected to said switch to determine whether said
switch is open or closed.
8. In the combination of claim 1, wherein said magnet and said reed
switch are oriented with respect to each other such that, in the
absence of a card in said way, the magnetic field from the magnet
is so weak at the switch that the switch is then open, said
magnetic material being so positioned that when the card is in said
position the magnetic material forms a paramagnetic path over a
substantial part of the distance between the switch and the magnet
to thereby increase the magnetic field at the switch to an extent
sufficient to close the switch.
9. In the combination of claim 8, wherein said switch and said
magnet are in planes parallel to and at opposite sides of said way,
with one respective ends of the switch and magnet being in
juxtaposition and the other respective ends being spaced from each
other, said magnetic material means being positioned to link said
other respective ends.
10. In the combination of claim 8, wherein said switch and said
magnet are in planes parallel to and at opposite sides of said way,
as viewed at right angles to said planes the respective ends of the
switch and magnet being spaced from each other, said magnetic
material means being positioned to link said respective ends when
said card is in said position.
11. In the combination of claim 1, wherein said magnet means
includes a second magnet positioned at said one side of said way
between the way and said switch, means mounting said second magnet
for movement toward and away from said way and biasing it toward
said way, the two magnets being so oriented that in the absence of
a card their magnetic fields repel and the second magnet is thereby
moved, against said biasing, away from said way and toward said
switch so that the magnetic field of the second magnet closes said
switch, said magnetic material means being positioned, when said
card is in said position, between said magnets thereby shunting
their magnetic fields to reduce said repulsion and allowing said
second magnet to move away from the switch under the influence of
said biasing thereby reducing the magnetic field at the switch
sufficiently to allow said switch to open.
12. In a card for use with a card reading device defining a way for
receiving said card at a given location in said way, which device
includes a reed switch positioned at one side of said way, said
reed switch being closed when a magnetic field of a relatively
strong strength condition is applied thereto and being open when a
relatively weak magnetic field strength condition is applied
thereto, magnet means including a magnet mounted on the opposite
side of said way, when said card is not in said way said magnetic
material means applies a magnetic field of one of said conditions
to said reed switch, the improvement wherein
said card being mainly non-magnetic material and including magnetic
material means of inconsequential residual magnetism, when said
card is at said location said magnetic material means being
positioned between the magnet and the switch and intercepting the
magnetic lines of force emanating from said magnet so that said
magnetic means applies a magnetic field of the other of said
conditions to said reed switch.
13. In the combination of claim 12, wherein said magnetic material
means is obscured from visual examination of the exterior of said
card.
14. A card reading device for use with a card formed primarily of
non-magnetic material and including a predetermined area of
magnetic material means at a particular location on the card, said
magnetic material means having inconsequential residual magnetism,
said device comprising:
frame means defining a pocket for said card such that when said
card is in said pocket said location is at a given position in said
pocket, magnet means mounted on said frame means and including a
magnet positioned at one side of said pocket adjacent said
location, said magnet means establishing a magnetic field of a
first strength at a point to the other side of said pocket when
said card is in said pocket and a magnetic field of a second,
different strength at said point when said card is displaced from
said pocket, and a reed switch positioned at said point, said
switch having an open condition when a relatively weak magnetic
field is applied thereto and a closed condition when a relatively
strong magnetic field is applied thereto, one of said first and
second strengths corresponding to said relatively strong magnetic
field and the other of said first and second strengths
corresponding to said relatively weak magnetic field, whereby when
said card is in said pocket said magnetic material means serves as
a shunt for a magnetic field between said magnet and said point so
that the magnetic field at said point will be different depending
on whether said shunt is present thereby causing the condition of
said switch to indicate whether said card is in said pocket.
15. A card reading device as set forth in claim 14, wherein said
device includes detecting means connected to said switch to
determine whether said switch is open or closed.
16. A card reading device as set forth in claim 15, for use with
said card wherein the card includes a plurality of said magnetic
material means at a plurality of locations on said card, said
device being characterized by:
a plurality of said magnet means each having said magnets
positioned respectively adjacent the locations of the magnetic
material means when said card is in said pocket, and a plurality of
said reed switches respectively positioned at the respective
points.
Description
SUMMARY OF THE INVENTION
The present invention relates to a provision of a simple and
inexpensive card reading device to supply information from a card
invisibly coded by a magnetic material embedded therein.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of an identification card or the like used in
conjunction with the present invention;
FIG. 2 is an enlarged partial section as seen at line 2--2 of FIG.
1;
FIG. 3 is a schematic plan view of a card reading device;
FIG. 4 is a side elevation of the reading device;
FIG. 5 is a bottom view of the card reading device;
FIG. 6 is a section seen at line 6--6 of FIG. 3;
FIG. 7 is a plan view of an alternative form of card and reading
device therefor;
FIG. 8 is a view corresponding to FIG. 7, with a portion of the
device broken away and with the card partially displaced from the
reading device;
FIG. 9 is a diagram used in illustrating the operation of the
reading devices;
FIG. 10 is a plan view of another alternate reading device;
FIG. 11 is a plan view of the reading device of FIG. 10 showing a
card positioned therein;
FIG. 12 is a partial section as seen at line 12--12 of FIG. 11;
FIG. 13 is a perspective view of a further embodiment of the
invention;
FIG. 14 is a section seen at line 14--14 of FIG. 13; and
FIG. 15 is a view corresponding to FIG. 14 with the card
removed.
DESCRIPTION OF SPECIFIC EMBODIMENTS
The following disclosure is offered for public dissemination in
return for the grant of a patent. Although it is detailed to ensure
adequacy and aid understanding, this is not intended to prejudice
that purpose of a patent which is to cover each new inventive
concept therein no matter how others may later disguise it by
variations in form or additions or further improvements.
EMBODIMENT OF FIGURES 1-6
FIGS. 3-6 illustrate a reading device of the present invention. It
comprises a frame or holder, generally 20, which defines a pocket
or way 21 for receiving a card, generally 22. The card has one
corner 23 cut away and the pocket has a corresponding obstructed
corner 24. Thus the card can be inserted into the pocket with only
one orientation if the card is to be fully received in the pocket
with the end of the card abutting the rear wall 25 of the pocket.
The card has a plurality of pieces 27 through 30 of magnetic
material embedded therein. The term magnetic material is employed
herein to refer to material that has a magnetic permeability
somewhat greater than that of a vacuum. As used in the present
invention, this magnetic material is not magnetized, other than
such inconsequential residual magnetism as might exist. The
material is used in the invention in the nature of a shunt rather
than in the nature of a magnetic. Numerous such materials are known
to those skilled in the art, the most common generally being
iron.
The remainder of the card is a non-magnetic material, such as a
plastic. Various procedures may be employed for embedding the
magnetic material units 27-30 therein. For example, the card may be
outer layers 32 and 33 of plastic with fillers 34 therein. After
these components have been positioned as desired the thermoplastic
material employed is fused together by heat. Thus the magnetic
units 27-30 are securely embedded therein at predetermined
locations with respect to the borders of the card, with the units
being invisible from the exterior of the card. Obviously,
components of the card also can be assembled with an adhesive.
Thus when the card 22 is inserted into the pocket 21 the magnetic
material units 27-30 are positioned at particular respective
locations in the pocket. At one side of the holder at each of the
respective locations is a magnet, the magnets being 37-40
respectively. At the opposite side of the holder at each of the
respective locations is a reed switch, the switches being 41-44
respectively. The term "reed switch" is used herein to refer to
those switches which are actuated by the presence of a magnetic
field. When the magnetic field at the switch is below a
predetermined strength the switch contacts are open and with a
relatively strong field at the switch the switch contacts are
closed. The arrangement of the respective pairs of magnets and
switches are such that the magnet holds the switch closed so long
as a card is not in the pocket. However, when a card is in the
pocket the respective units of magnetic material 27-30 are
positioned between the respective magnets and switches. The
magnetic field instead of reaching to the switch in sufficient
strength to operate the switch is shunted through the respective
paramagnetic unit. Thus in FIG. 5 the field between the north and
south poles of the magnet 37 passes mainly through the shunt 27 and
very little 45 that field extends above the shunt. Thus the
contacts 46 and 46 of the switch 41 are open. Removal of the card
would result in the switch contacts closing.
The face of the holder 20 at which the switches 41-44 are mounted
is formed like a printed circuit board. There is a common conductor
48 connected to one side of each of the switches (e.g., contact 45)
and there are separate conductors 49-50 connected to the other side
of each of the switches 41-44 respectively (e.g., contact 46).
Various control devices can be connected to the switches to
indicate which of the switches are open and which are closed at a
particular time and to provide suitable automatic reaction
depending upon the existing setting of the switches. Just by way of
illustration the detecting device, generally 55, is illustrated in
FIG. 3. Here there are relays 56, 57 and 58 connected in series
with switches 42-44 respectively and a source of electric power 59.
Also by way of illustration a light 60 is connected in series with
switch 41 and battery 59. If, for example, a card having only
magnetic units 28 through 30 were inserted into the holder 20 the
relays 56-58 would all drop out because of the respective switches
being opened by the units 28-30, but the light 60 would remain lit.
Various combinations of coded cards can thus be provided and the
coding on the card can be determined from the position of the
switches. The cards are not limited to having four units of
magnetic material therein as in the illustrated embodiment.
EMBODIMENT OF FIGURES 7-8
Here the holder or frame, generally 62, has a pocket 63 for
receiving a card 64. The card has a unit 65 of magnetic material
embedded therein.
At one side of the holder is a reed switch 67 connected to two
conductors 68 and 69. At the other side of the holder is a bar
magnet 70. The magnet is positioned at an angle with respect to the
reed switch and in a location such that one of its poles, e.g., the
pole at end 70a is relatively close to the reed switch while the
pole at end 70g is relatively remote from the reed switch. Thus if
there is not a card in the pocket the strength of the magnetic
field from the magnet 70 being impressed on the reed switch 67 is
insufficient to cause a closing of the contacts of the switch. The
switch thus remains in the open position. However, when the card 64
is fully inserted into the pocket 63, the unit 65 forms a
paramagnetic path between the pole at end 70g and the reed switch.
Now there is sufficient magnetic field at the reed switch 67 so as
to operate the switch and the switch is in the closed position. As
the card is withdrawn slightly to the position illustrated in FIG.
8, the function of the magnetic unit 65 changes from that of
providing a path to the switch and the unit again commences to act
as a shunt to the magnetic field of the magnet causing the switch
to open. Of course, further removal of the card will also cause the
switch to be in the open position.
EMBODIMENT OF FIGURES 10-12
Here there is a frame or holder, generally 72. It has a pocket 73
for receiving a card 74. At one side of the holder is a reed switch
75. At the opposite side is a bar magnet 76. Here again the magnet
is sufficiently remote from the switch 75 so that the extent of the
magnetic field reaching the switch is insufficient to close the
contacts of the switch. However, the card 74 has two units 77 and
78 of magnetic material embedded therein. When the card 74 is fully
in the pocket, as illustrated in FIGS. 11 and 12, the units 77 and
78 each form a paramagnetic path between respective ends of the
magnet and switch. This causes a substantial increase in the
strength of the magnetic field occurring at the switch so that that
field is now sufficiently strong to cause the switch to close. Of
course, in this embodiment, as well as in the embodiment of FIGS. 7
and 8, a plurality of pairs of switches and magnets could be
employed. Only one pair is illustrated and described since this is
sufficient to convey the concept involved.
EMBODIMENT OF FIGURES 13-15
In this embodiment there is a holder or frame, generally 80. It has
a pocket or way 81 to receive a card 82. This card has two units 83
and 84 of magnetic material embedded therein. Of course, these
units are at a particular location in the pocket when the card is
fully inserted into the pocket. The switch operating mechanisms are
identical so that only that associated with unit 83 will be
described.
At one side of the holder at the location of unit 83 is a magnet
86. This magnet is fixed in place. At the opposite side of the
holder is a magnet 87 mounted on a spring arm 88. The arrangement
is such that the magnet 87 is biased to its position against the
holder, as illustrated in FIG. 14. This biasing could either be by
gravity or by the spring action of arm 88. Above the magnet 87 is a
reed switch 89. This is mounted to holder 80 by suitable means, not
shown.
The magnets have the poles closest to each other of the same
polarity (north in the illustrated embodiment) so that these
magnets repel each other. When a card is not in the pocket, as
shown in FIG. 15, the repulsion of the magnets raises magnet 87 so
that it approaches reed switch 89. Magnet 87 is now sufficiently
close to switch 89 so that its magnetic field is sufficient to
close the contacts of the switch. However, when card 82 is inserted
into the pocket, as illustrated in FIG. 14, the unit 83 is
positioned between the two magnets and serves as a shunt to the
magnetic field of each of the magnets. This shunt reduces the
repulsion effect between the like poles of the magnet and the
biasing of the mounting of magnet 87 causes it to descend to the
FIG. 14 position. In doing so, magnet 87 moved away from switch 89
to an extent such that its magnetic field is no longer sufficient
to hold the switch contacts in the closed position. Thus the switch
contacts are open.
FIG. 9 illustrates the general concept of the operation of a reed
switch. If the switch is open and the magnetic field strength is
relatively low, the switch remains open. Thus, starting at the
lower left the switch remains open in the magnetic field strengths
indicated by the numbers 1, 2 and 3. However, upon reaching the
field strength indicated by the number 4, the switch suddenly
closes and remains closed with further increases in the magnetic
field strength. Going in the opposite direction and starting with
the switch contacts closed (the upper line) the contacts remain
closed though the field strength decreases from 5 to 4 and then to
3. However, when the field strength diminishes to 2 the switch
contacts suddenly open and continue to stay open with further
decreases in the field strength.
The embodiments of this invention are particularly advantageous
because of their simplicity and low cost. While perhaps not as much
data can be coded (stored) in a card as in some other systems, it
is more than adequate for many applications (e.g., a key to a
door). Furthermore, the coding is not revealed upon an ordinary
visual examination.
* * * * *