Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to a portable and manually
manipulatable encoder for encoding magnetic data in the
form of "spots" or patterns on the surface of cards or
card keys. A card key of the type which lends itself
to use with the present invention is seen in my U.S.
Patent No. 4077242, issued March 7, 1978.
In the past, most conventional card keys have
been uniformly encoded with their magnetic patterns at
the factory. In other words, the end user has never
been provided with any equipment which would permit him
to apply the desired code of magnetic spots to the surface
of cards or card keys to be employed by such user. For
these reasons considerable delay is encountered if the
card or card key user desires to change the combination
of a card key or to encode a blank card key or the like.
In a primary aspect, this provides a relatively
simple hand held encoder which can be manually manipulated
by the user to apply magnetic spots as required to magnetic
cards and card keys.
Another aspect of the invention is the provision
of a relatively small encoder which is light enough to
be readily manipulated by the user and at the same time
containing all of the apparatus and wiring required to
create a relatively strong flux required to encode.
Accordingly, this invention provides a hand held
encoder for encoding magnetic card keys and the like
comprising:
housing adapted to be manually held and manipulated,
a probe mounted on said housing and having an
outer tip adapted to be applied against a surface to
be magnetized,
an electrical circuit in said housing and including:
a supply of direct current,
windings around said probe, and
a capacitor,
a switch on said housing for discharging
said capacitor through said windings to provide a magnetic
field for magnetizing a spot at said surface when said
tip is applied thereto,
said housing being formed with a portion thereof
providing a pistol grip, said switch being secured to
said grip and adapted to be actuated by a finger of the
user.
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Other aspects and advantages of the invention
will be apparent from the following specification and
from the drawings
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1 Fig. l is a side elevation of the preferred form of the
2 ¦ encoder with the front half of the housing removed to show
3 I internal structure.
4 Fig. 2 is a side elevation of the encoder in use to apply
5 1 a magnetic spot to a card key.
6 Fig. 3 is a top plan view of the encoder of Fig. 2.
7 Fig. 4 is a schematic wiring diagram of the circuitry.
8 The encoder comprises a molded housing, preferably of
9 plastic, which is centrally split before final assembly to provide
one half, indicated at lA in Fig. l, and the opposite sim~lar
11 half indicated at lB in Figs. 2 and 3. The housing includes a
12 bottom wall 2 and side walls 3 which combine to form a pistol
13 grip wherein the complete thickness of the housing is less than
14 one-half the width of the housing as is shown in Fig. 3. The
sidewalls 3 and top 4 of the housing terminate in an enlarged
16 opening 5 in which is received a support 6 which is recessed
17 within the opening 5 for fixedly securing said support to the
18 housing.
19 Fixedly secured within a central aperture 7 in support 6
is a coil 8 which may consist of about lSO turns of No. 24
21 magnet wire and which coil is adapted to create magnetic lines of
22 force for applying a strong flux to a centrally positioned probe
23 9 which is adapted to be applied by the user to the card to be
24 encoded as seen in Fig. 2. Only the major elements of the
circuitry are sho~n in Fig. l since the entire circuitry is shown
26 schematically in Figo 4. First referring to Fig. 4 the encoder
27 is connected by means of lines lO, ll to a power supply 12 which
28 includes a charging resistance 13.
29 A trigger swltch generally designated lS is employed to
charge and discharge a capacitor 16. In parallel with capacitor
31 16 is a lamp 17 which indicates~the condition of capacitor 16.
32 When the trigger switch 15 is moved to its up position,
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as seen in Fig. 4, capacitor 16 discharges through coil
8 to create the desired magnetic field in probe 9. To
obtain uniformity in the strength of the magnetic field
it is preferable to discharge the capacitor 16 through
a silicone controlled rectifier 20 in which the gate 21
is connected to the circuit through a resistance 22 to
provide the desired voltage drop. Also in the circuit
of coil 8 is a polarity switch 25 by which the user may
reverse the polarity of the flux impressed on the card
to be encoded.
Referring again to Fig. 1 it is seen that the
trigger switch 15 is in the form of a push button which
is convenient to the forefingers of the user when the
desired pulse is to be generated in the probe.
The polarity switch 25 is also in close proximity
to the forefingers of the user so that it is a simple
matter to switch from one polarity to another as the coding
of the card requires.
Although the size of the capacitor required
in a circuit of the subject type is fairly large, such
capacitor is readily received in the space available in
the housing 1. The lamp 17 may be supported on a support
30 which in turn is secured to the top wall 4 of the housing
1 so that the operator may readily see the condition of
the lamp 17.
Not only does the lamp provide a means for determining
that the capacitor 16 is charged but it also indicates
when the unit is connected to power and when it is disconnected.
Furthermore, the lamp 17 bleeds off the charged capacitor
through the filament so that the encoder is not stored
with a charged capacitor. If desired, an on/off switch
(not shown) may be incorporated in the circuit.
In use and referring to Fig. 2 it will be seen
that the encoder 1 may be employed with a template 33
which is adapted to hold a card 32 in the desired position
while the probe 9 is
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applied against said card to impress the magnetic spots thereon.
2 Said template 33 may be provided with a nonmagnetic guide plate
3 ¦ 34 which is formed with apertures arranged in a predetermined
4 I pattern to receive the probe 9 therethrough, thus insuring that
5 ¦ the magnetic spots are applied at the correct points. The
6 ¦ template 33 is not shown in detail since it forms no part of the
7 ¦ instant invention except in combination with the disclosed
8 ¦ invention as claimed in the following claims.
9 ¦ The present invention also contemplates the use of a dry
10 ¦ cell battery as the source of direct current. Sald battery may
11 ¦ be substituted for the power supply 12 and lines 10, 11. As seen
12 in Fig. 1 such battery may be positioned in the upper portion of
h sing I as indlcated at 40 by dot-dash lines.
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31
32
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