PORTABLE RADIO BATTERY PACK WITH ON-OFF SWITCH

BLOC-BATTERIE A INTERRUPTEUR POUR APPAREIL RADIO PORTATIF

English Abstract

45 MR 482

PORTABLE RADIO BATTERY PACK
WITH ON-OFF SWITCH


Abstract of the Disclosure
An improved arrangement for powering a two-
way portable radio or the like comprises rechargable
battery cells and sets of power input and output contacts
interconnected to each other and the battery cells in such
a way that the output contacts may be electrically
connected to the battery cells for powering the ratio,
or to the input contacts for receiving power directly
from a battery charger for dead battery operation while
simultaneously recharging the battery cells, all battery
pack contacts being electrically isolated from the battery
cells in the latter mode of operation.

Claims

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The embodiments of the invention in which an
exclusive property or privilege is claimed are defined
as follows:
1. A modular battery pack for powering a
radio comprising:
a rechargeable battery cell;
a set of power output contacts;
a set of power input contacts;
means for electrically interconnecting said
input and output contacts and said battery cell such
that said output contacts may be alternatively
interconnected to said battery cell, or to said input
contacts while simultaneously electrically isolating
battery cell power from said input and output contacts.
2. A modular battery pack for powering a
radio comprising a rechargeable battery cell and sets of
input and output contacts interconnected to each other
and said battery cell in such a way that said output
contacts may either be electrically connected to said
battery cell for powering said radio in a first
operating mode, or electrically connected to said input
contacts for receiving power from a battery charger for
dead battery operation in a second operating mode while
simultaneously recharging said battery cell, and wherein
battery cell power is electrically isolated from said
input and output contacts.
3. Modular radio and battery pack apparatus
comprising:
a radio module; and
a modular battery pack removably attachable to
said radio module for providing power thereto through
first mating electrical contacts on said radio module
and said battery pack and removably attachable to a
battery charger through second mating electrical
contacts on said battery charger and said battery pack,





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said battery pack comprising a battery cell, electrical
circuitry interconnecting said battery cell with said
first and second battery pack electrical contacts, and
switch means for interrupting said battery pack
electrical circuitry to prevent battery cell power from
reaching said first and second battery pack electrical
contacts during removal of said battery pack from said
radio module.
4. A modular battery pack for providing power
for a portable radio to which it may be attached in
modular fashion comprising:
at least one rechargeable battery cell having
positive and negative terminals;
first and second power output contacts for
removably electrically interconnecting said modular
battery pack to said radio;
first, second and third power input contacts
for removably electrically interconnecting said modular
battery pack to a battery charger, said first power
input contact being electrically connected to said first
power output contact and said negative battery cell
terminal; and
a switch alternatively electrically connecting
said second power output contact to said third power
input contact in an OFF position or to said positive
battery cell terminal and said second power input
contact through an isolation diode in an ON position;
whereby, with said switch in said ON position,
battery cell power is available at said first and second
power output contacts; and, with said switch in said OFF
position and said battery pack unconnected to said
charger, no battery cell power is available at any of
said power input or power output contacts, and with said
switch in said OFF position and said battery pack
connected to said charger, said first and second power

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output contacts are powered while said battery cell may
be recharged by said charger.
5. Apparatus for powering a portable radio
comprising:
a battery charger for converting AC current to
DC current, said charger having two positive output
terminals and one negative output terminal; and
a modular battery pack for providing DC power
for a radio module comprising:
a rechargeable battery cell;
two power output contacts for interconnecting
to said radio;
three power input contacts for electrically
connecting said battery charger terminals, the first
power input contact being electrically connected to the
first power output contact and said battery cell and for
also electrically connecting to the negative one of said
charger terminals; and
a switch electrically connecting, in an ON
position, the second power output contact with said
battery cell and, through an isolation diode, the second
power input contact, and further connecting, in an OFF
position, said second power output contact with the
third power input contact, said second and said third
power input contacts each being electrically connectable
with different ones of said positive charger terminals;
whereby, with said switch in said On position,
battery cell power is available at said power output
contacts; with said switch OFF and said power input
contacts unconnected to said charger, no battery cell
power is available at any of said power input and power
output contacts; and, with said switch OFF and said
power input contacts connected to said charger, dead
battery operation of said radio is possible during
recharging of said battery cell.

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6. A rechargeable, removable battery pack for
providing power to a portable radio comprising:
a rechargeable battery cell electrically
connected across a first positive power input contact
through an isolation diode, and a second negative power
input contact to form a charging circuit for receiving
power from mating contacts of an attachable battery
charger;
a third positive power input contact for
receiving power from another mating contact of said
battery charger for powering said radio; and
two power output contacts for supplying power
to mating radio contacts, said first power output
contact being electrically connected to said second
negative input contact and said battery, and said second
power output contact being electrically connected to a
switch operable between an ON position in which said
first and second output contacts are placed in parallel
electrical relationship with said charging circuit,
thereby providing battery cell power to said power
output contacts, and an OFF position in which said
second output contact is electrically connected to said
third positive power input contact, thereby permitting
battery charger power to be provided to said power
output contacts to directly power said radio and also
thereby isolating battery cell power from all of said
power input and power output contacts.
7. A modular battery pack comprising:
a rechargeable battery cell;
first and second power output contacts, the
first of which is electrically connected to said battery
cell and a first power input contact;
a second power input contact electrically
connected to said battery cell through an isolation
diode so as to provide, in combination with said first

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power input contact, an electrical charging circuit for
said battery cell;
a third power input contact; and
means for switching said second power output
contact into alternative electrical connection with said
second and third power input contacts; and
wherein said power output contacts provide
removable electrical connection between said modular
battery pack and a radio module, and said power input
connections provide removable electrical connection
between said modular battery pack and a battery charger.
8. A rechargeable modular battery pack for
providing power to a portable radio module comprising:
a rechargeable battery cell electrically
connected through an isolation diode to first and second
power input contacts to form a charging circuit for
receiving power from mating contacts of an attachable
battery charger,
a third power input contact for receiving
power from another mating contact of said battery
charger for powering said radio module independently of
said battery cell; and two power output contacts for
supplying power to mating contacts of said radio module,
the first such power output contact being electrically
connected to said battery cell and said first power
input contact, and said second power output contact
being electrically connected to a switch for selectively
placing said two power output contacts either in
parallel electrical connection with said charging
circuit, thereby powering said radio by means of said
battery cell, or placing said two power output contacts
in parallel electrical connection with said first and
third power input contacts while isolating battery cell
power from all power input and power output contacts.

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9. A modular battery pack comprising:
a rechargeable battery cell electrically
connected across a pair of power input contacts through
an isolation diode, thereby preventing discharge of said
battery cell through said pair of power input contacts;
a pair of power output contacts, a first of
which is electrically connected to one of said pair of
power input contacts; and
means for switching the second of said power
output contacts between electrical connection with the
other of said pair of power input contacts and a third
power input contact which is electrically isolated from
said battery cell; and
wherein said power output contacts provide
removable electrical connection between said modular
battery pack and a radio, and said power input
connections provide removable electrical connection
between said modular battery pack and a source of DC
power.

Description

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PORTABLE RADIO BATTERY PACK
ITH ON-OFF SWITCH
Background of the Invention
The present invention relates to batteries and,
more particularly, to rechargeable battery packs for use
with portable two-way radios.
Portable two-way radios and similar devices
are typically powered by rechargeable batteries, such
as nickel-cadmium battery cells packaged in a battery
pack which is easily removable from the radio for recharging
in a battery charger. The size of the battery pack and
the number of cells vary, depending on the power and
operational life of the battery required between
chargings.
It is necessary on portable radios that means
be provided for switching off battery power when the
radio is not used in order to conserve battery life.
It is also desirable to be able to operable the radio in
a battery charger circuit, even if the battery is dead
or defective, as a back-up mode of operation. Thus, an
uncharged or defective battery should not cause loss of
communications as long as a battery charger is available.
This is referred to as dead battery operation. It is
also desirable to be able to electrically isolate the
battery terminals when the battery pack is being
disconnected from the radio to prevent arcing. This is
particularly desirable in the presence of explosive
gases which could be ignited by such arcing.

-` ~~
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Prior art radios conflne the on-off switch to
the radio body itself. This location requires that an
electrical conductor be routed from the radio's battery
contacts to the switch, and thereafter to a radio systems
connection and/or distribution point. Generally, -the size
of the electrical conductor is relatively large in order
to keep the electrical losses to a minimum. This presents
several problems in a portable hand-held radio. First,
a large electrical conductor takes up substantial space
in an already crowded portable radio. Second, routing the
electrical conductor through the systems portion of the
radio usually results in a loss of accessibility to
electrical components also located in that area.
Dead battery operation in prior art radios has
been provided by means of switching contacts in the radio
or isolation diodes in the battery, radio or charger
circuits. These components add complexity and/or
expense.
Summary of the Invention
Accordingly, it is the primary object of the
present invention to provide an improved arrangement for
powering a portable radio in which the battery power
switch is not located in the control systems portion of
the radio. It is a further object of the present
invention to provide a battery pack for a portable two-
way radio which can be electrically isolated from the
radio during battery removal.
It is yet another object of the present
invention to provide a battery pack arrangement for a
portable two-way radio which will accommodate dead
battery operation.
These and other objects and advantages will
be more clearly understood from the following detailed
description, drawings and specific examples, all of which
are intended to be typical of rather than in any way
limiting to the scope of the present invention.

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Briefly stated, the above objectives are
accomplished in one embodiment of the present invention
in which the battery on-off switch is located in the
battery pack instead of in the radio control systems
section. Two sets of contracts are provided on -the
battery pack - one set interconnects to the radio for
providing the radio with power; the other set inter-
connects with a charger for recharging the battery pack
and for dead battery operation.
A first one of the radio contacts is
internally electrically connected to the negative
battery cell terminal and a first one of the charger
contacts ~negative~. The other radio contact is
connected to the on-off switch. One pole of the
on-off switch ~the ON pole~ is connected to the
positive battery cell terminal and, through an isolation
diode, to a second (positive) charger contact. With
the switch in the OFF position, the second radio contact
is connected directly to another (third) positive
charger contact for dead battery operation. When
the battery is removed from the radio and the switch
is in the OFF position, no power is available at any
of the battery pack contacts since the positive
(second) charger contact is diode isolated, greatly5 reducing the risk of accidental battery discharge.
Brief De'scrip'ti'on'of''the Drawi'ngs
While the specification concludes with claims
particularly pointing out and distinctly claiming the
subject matter which is regarded as part of the present
invention, it is believed that the invention will be
more fully understood from the following description of
the preferred embodiment which is given by way of
example with the accompanying drawings in which:
Figure 1 is a frontal view of a portable
two-way radio having a battery pack embodying the subject
invention;

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Figure 2 is a side view of the portable two-
way radio of Figure l;
Figure 3 is a perspective view of a battery
pack constructed in accordance with the present
invention; and
Fi~ure 4 is a circuit diagram of the battery
pack of Figure 3.
Descrip'tion of the Preferred Embodiment
. . . , _ .
Referring to the drawings wherein like
numerals correspond to like elements throughout,
attention is first directed to Figures 1 and 2 wherein
a typical portable two-way radio 10 is depicted. Such
a radio comprises a radio portion 12 which contains a
transmitter and receivex (.transceiver~ and associated
eleetronic control equipment, and a battery pack 14
which is attached to and powers the radio portion 12.
T~e radio portion 12 has a generally rectangular
housing 16 which includes speaker and microphone
portion 18, a key pad 20 for "dialing" selected
other radios or telephones, an LCD display window 22
for displaying called numbers and other programmed
information, a control panel 24 on the top of the radio
having switches and/or knobs for squelch control,
channel selection, volume and the like, and an antenna
26 for receiving and radiating a radio signal. Push
to talk button 28 is located on the side of the radio
just below the section 30 containing electrical contacts
whieh mate with a universal deviee connector (UDC) for
aeeessory attaehment and/or remote eontrol of the radio.
The UDC contact section 30 of the radio is the subject
of a commonly=assigned U.S. Patent No. ~ o
issued Ja n ~ a ~ J~
Referring to Figure 3, the battery pack 14 is
shown to have mounted on its side an on-off power switch
32 which controls the flow of current to a pair of
output radio contacts 34, 36 on the top of the battery




,,, '' ,.. ~ .
. .

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pack. When installed on the radio, contacts 34, 36 are
brought into electrical contact with mating terminals
on the bottom of the radio housing 16. The internal
circuitry of battery pack 14 will now be described in
detail with specific reference to Figure 4.
As shown in Figure 4, the battery pack power
output contacts 34, 36 are connectable to mating
terminals 3a, 40, respectively, on radio portion 12.
A second set of power input contacts 42, 44, 46 inter-
connects with cooperating terminals 48, 50, 52, respect-
ively, on a battery charger 54 which converts AC current
from source 56 to DC current for charging battery pack
14 and ~or providing dead battery operation of the
radio.
Contact 34 is electrically connected to contact
46 and the negative terminal of internal battery cells
58, preferably of the nickel cadmium type. Contact 36
is electrically connected to switch 32 having an OFF
and ON position. With switch 32 in the OFF position,
radio side contact 36 is electrically connected to
charger side contact 42. The ON side of switch 32 is
electrically connected to the positive terminal of
battery cells 58 and to battery side contact 44 through
isolation diode 62.
For normal radio operation, contact pairs 34,
38 and 36, 40, are connected and switch 32 is placed
in the ON position to provide battery power to the radio
portion. However, when connected to battery charger
54, power may be delivered from source 56, through switch
32 in the OFF position, to the radio circuits. Battery
cells 58 may also be independently charged through the
(+) battery contact 50 with the radio connected to or
disconnected from the battery pack 14. If the battery
cell 58 are short circuited or otherwise defective, the
radio 12 may still be operated if connected to the
charger through the battery pack with switch 32 in the

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OFF position.
Note that when battery pack 14 is removed from
radio portion 12 with switch 32 in the OFF position, no
power is available at any of the battery pack contacts
34, 36, 42, 44, 46 because contact 44 is diode isolated.
This greatly reduces the risk of accidental arciny during
battery pack removal.
In addition, it should be noted that battery
power entering radio portion 12 may be routed directly
to a main distribution point in the most convenient
manner because it is no longer necessary to provide a
power control in the electronics section of radio portion
12.
The best mode contemplated for carrying out
this invention has been set forth in the description
above. It should be obvious, however, to one skilled
in the art that certain changes can be made to the
above-described invention without departing from the
broad inventive concepts thereof. It is intended that
the appended claims cover such variations in the present
invention's broader inventive concepts.

Representative Drawing