 |
Claims  |
|
|
I claim:
1. A power distribution and fuse panel unit for installation in a vehicle
to facilitate connection of various vehicle auxiliary electrical devices
having different power disconnect requirements, comprising:
a modular unit having a constant power input terminal adapted to be
connected with a battery to provide a source of constant D.C. voltage, and
an ignition controlled power input terminal adapted to be connected to an
ignition system of the vehicle to provide a source of ignition controlled
D.C. voltage upon the ignition system being turned on;
a plurality of constant power output terminals connected with said constant
power input terminal for connecting auxiliary electrical devices to be
supplied with constant power independently of the operation of the vehicle
ignition system;
a plurality of delayed shut-off power output terminals connected with said
constant power input terminal and with said ignition controlled power
input terminal for connecting auxiliary electrical devices to be supplied
with power for a predetermined time interval after the ignition system has
been turned off;
fuse elements connected between said constant power input terminal and said
plurality of constant power output terminals and between said constant
power input terminal and said plurality of delayed shut-off power output
terminals; and
timing means and relay means connected between said constant power input
and ignition controlled power input terminals and said plurality of
delayed shut-off power output terminals to provide voltage to said
plurality of delayed shut-off power output terminals upon said ignition
system being turned on, and after a predetermined time interval after the
ignition system has been turned off, to disconnect voltage to said
plurality of delayed shut-off power output terminals.
2. The power distribution and fuse panel unit according to claim 1 further
comprising;
a plurality of input and output terminals independent from said vehicle
battery and said vehicle ignition system;
each of said input and output terminals joined together by a respective
lead having a fuse holder for receiving fuses to provide a plurality of
individual fused circuits for connecting externally powered devices.
3. The power distribution and fuse panel unit according to claim 1 further
comprising;
a test switch and testing circuit operatively connected with said timing
means to selectively shorten the time interval between the ignition system
being turned off and the disconnection of voltage to said plurality of
delayed shut-off power output terminals to quickly determine the
operational status of the power distribution and fuse panel unit.
4. The power distribution and fuse panel unit according to claim 1 wherein
said timing means includes an interconnected integrated circuit binary
counter and an integrated flip-flop circuit;
said ignition controlled power input terminal is connected with said
counter and said flip-flop circuit;
said relay means includes a delayed shut-off power relay connected between
said constant power input terminal and said flip-flop circuit and having
normally open contacts connected with said plurality of delayed shut-off
power output terminals;
said ignition controlled power input terminal is connected with said
delayed shut-off power relay to close said contacts and thereby supply
D.C. voltage to said plurality of delayed shut-off power output terminals
upon the ignition being turned on; and
said counter being activated upon the ignition system being turned off, and
after the predetermined time interval said flip-flop circuit opens said
contacts to disconnect voltage to said plurality of delayed shut-off power
output terminals.
5. A power distribution and fuse panel unit for installation in a vehicle
to facilitate connection of various vehicle auxiliary electrical devices
having different power disconnect requirements, comprising:
a modular unit having a constant power input terminal adapted to be
connected with a battery to provide a source of constant D.C. voltage, and
an ignition controlled power input terminal adapted to be connected to an
ignition system of the vehicle to provide a source of ignition controlled
D.C. voltage upon the ignition system being turned on;
a plurality of constant power output terminals connected with said constant
power input terminal for connecting auxiliary electrical devices to be
supplied with constant power independently of the operation of the vehicle
ignition system;
a plurality of ignition controlled power output terminals connected with
said ignition controlled power input terminal for connecting auxiliary
electrical devices to be supplied with ignition controlled power when the
ignition system is turned on;
a plurality of delayed shut-off power output terminals connected with said
constant power input terminal and with said ignition controlled power
input terminal for connecting auxiliary electrical devices to be supplied
with power for a predetermined time interval after the ignition system has
been turned off;
fuse elements connected between said constant power input terminal and said
plurality of constant power output terminals, between said constant power
input terminal and said plurality of ignition controlled power output
terminals, and between said constant power input terminal and said
plurality of delayed shut-off power output terminals; and
timing means and relay means connected between said constant power input
and ignition controlled power input terminals and said plurality of
ignition controlled power output and plurality of delayed shut-off power
output terminals to provide ignition controlled voltage to said plurality
of ignition controlled power output and said plurality of delayed shut-off
power output terminals upon said ignition system being turned on, and to
immediately disconnect voltage to said plurality of ignition controlled
power output terminals upon the ignition system being turned off, and
after a predetermined time interval after the ignition system has been
turned off, to disconnect voltage to said plurality of delayed shut-off
power output terminals.
6. The power distribution and fuse panel unit according to claim 5 wherein
said timing means includes an interconnected integrated circuit binary
counter and an integrated flip-flop circuit;
said ignition controlled power input terminal is connected with said
counter and said flip-flop circuit;
said relay means includes an ignition controlled relay connected with said
ignition controlled power input terminal and having normally open contacts
connected with said plurality of ignition controlled power output
terminals;
said contacts being closed upon the ignition system being turned on and
thereby supply D.C. voltage to said plurality of ignition controlled power
output terminals; and
said contacts being opened upon the ignition system being turned off to
disconnect voltage to said plurality of ignition controlled power output
terminals.
7. The power distribution and fuse panel unit according to claim 5 wherein
said timing means includes an interconnected integrated circuit binary
counter and an integrated flip-flop circuit;
said ignition controlled power input terminal is connected with said
counter and said flip-flop circuit;
said relay means includes an ignition controlled relay connected with said
ignition controlled power input terminal and having normally open contacts
connected with said plurality of ignition controlled power output
terminals, and a delayed shut-off power relay connected with said ignition
controlled power input terminal and connected between said constant power
input terminal and said flip-flop circuit, and said delayed shut-off power
relay having normally open contacts connected with said plurality of
delayed shut-off power output terminals;
said ignition controlled relay contacts and said delayed shut-off power
relay contacts being closed upon the ignition system being turned on and
thereby supply D.C. voltage to said plurality of ignition controlled power
output terminals and to said plurality of delayed shut-off power output
terminals, respectively; and
upon the ignition system being turned off, said ignition relay contacts
open thereby disconnecting voltage to said plurality of ignition
controlled power output terminals and said counter is activated, and after
the predetermined time interval said flip-flop circuit opens said delayed
shut-off power relay contacts to disconnect voltage to said plurality of
delayed shut-off power output terminals.
8. The power distribution and fuse panel unit according to claim 5 further
comprising:
a plurality of input and output terminals, independent from said vehicle
battery and said vehicle ignition system;
each of said input and output terminals joined together by a respective
lead having a fuse holder for receiving fuses to provide a plurality of
individual fused circuits for connecting externally powered devices.
9. The power distribution and fuse panel unit according to claim 5 further
comprising;
a test switch and testing circuit operatively connected with said timing
means to selectively shorten the time interval between the ignition system
being turned off and the disconnection of voltage to said plurality of
delayed shut-off power output terminals to quickly determine the
operational status of the power distribution and fuse panel unit.
10. A power distribution and fuse panel unit for installation in a vehicle
to facilitate connection of various vehicle auxiliary electrical devices
having different power disconnect requirements, comprising:
a modular unit having a constant power input terminal adapted to be
connected with a battery to provide a source of constant D.C. voltage, and
an ignition controlled power input terminal adapted to be connected to an
ignition system of the vehicle to provide a source of ignition controlled
D.C. voltage upon the ignition system being turned on;
a plurality of constant power output terminals connected with said constant
power input terminal for connecting auxiliary electrical devices to be
supplied with constant power independently of the operation of the vehicle
ignition system;
a plurality of ignition controlled power output terminals connected with
said ignition controlled power input terminal for connecting auxiliary
electrical devices to be supplied with ignition controlled power when the
ignition system is turned on;
fuse elements connected between said constant power input terminal and said
plurality of constant power output terminals and between said constant
power input terminal and said plurality of ignition controlled power
output terminals; and
timing means and relay means connected between said constant power input
and ignition controlled power input terminals and said plurality of
ignition controlled power output terminals to provide ignition controlled
voltage to said plurality of ignition controlled power output terminals
upon said ignition system being turned on, and to immediately disconnect
voltage to said plurality of ignition controlled power output terminals
upon the ignition system being turned off.
11. The power distribution and fuse panel unit according to claim 10
wherein
said timing means includes an interconnected integrated circuit binary
counter and an integrated flip-flop circuit;
said ignition controlled power input terminal is connected with said
counter and said flip-flop circuit;
said relay means includes an ignition controlled relay connected with said
ignition controlled power input terminal and having normally open contacts
connected with said plurality of ignition controlled power output
terminals;
said contacts being closed upon the ignition system being turned on and
thereby supply D.C. voltage to said plurality of ignition controlled power
output terminals; and
said contacts being opened upon the ignition system being turned off to
disconnect voltage to said plurality of ignition controlled power output
terminals.
12. The power distribution and fuse panel unit according to claim 10
further comprising:
a plurality of input and output terminals, independent from said vehicle
battery and said vehicle ignition system;
each of said input and output terminals joined together by a respective
lead having a fuse holder for receiving fuses to provide a plurality of
individual fused circuits for connecting externally powered devices. |
|
 |
|
 |
Claims |
|
|
|
Description |
|
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to vehicle auxiliary electrical equipment
and fuse panels and more particularly to a D.C. power distribution and
fuse panel unit for connecting a plurality of vehicle auxiliary electrical
devices which is controlled by the vehicle ignition and has constant
power, ignition controlled, and delayed power shut-off circuits for the
various devices.
2. Brief Description of the Prior Art
The installation and trouble shooting of vehicle auxiliary electrical
equipment such as two-way radios, sirens, computers, and mobile phones in
police and other emergency vehicles has heretofore been a time consuming
and expensive process. Several variations of installation methods have
existed through the years, each tailored to the requirements of the
auxiliary equipment and the needs of the particular organization using the
vehicles.
Some organizations wire the auxiliary electrical equipment through ignition
operated relays so that the equipment is automatically turned off when the
vehicle ignition is turned off.
Other organizations use relays with timers to achieve a delayed shut-off
required by a computer mobile data terminal (MDT) to prevent a slow down
or total shut down of its host computer when it cannot deliver messages
back to the MDT because it has been turned off.
Still other organizations simply wire the auxiliary electrical equipment
hot (connected direct to the battery) and depend on the operator to
physically turn off each piece of equipment separately.
All of the installation methods described above have certain drawbacks and
limitations. The ignition controlled relay installation requires the
vehicle ignition switch to be turned on (keys in the vehicle) to operate
the equipment. Wiring the auxiliary electrical equipment hot causes dead
batteries when the operator forgets to turn the equipment off. The delayed
shut-off relay and timer combination keeps all equipment active during the
shut-off delay.
Regardless of the installation method used, each piece of auxiliary
electrical equipment still requires one or more power leads that usually
have an in-line fuse holder spliced into the wire. When relays are used,
they must be mounted and wired into the system. This is usually
accomplished under the hood of the vehicle, and each wire must be passed
through the firewall of the vehicle to reach the auxiliary equipment. In
the case of a police vehicle emergency light bar, it may have as many as
eight leads and each circuit in the light bar requires an in-line fuse to
protect the light controller.
Thus, installation of vehicle auxiliary electrical equipment such as
two-way radios, sirens, computers, and mobile phones in police and other
emergency vehicles is a labor intensive time consuming process and the
resultant large bundle of wires makes trouble shooting a simple blown fuse
a major ordeal. The task of replacing a blown fuse usually requires
unbundling the numerous wires so that a wire could be traced to the proper
in-line fuse holder and then rebundling the numerous wires after the blown
fuse is replaced.
There are several patents which disclose systems for controlling auxiliary
power devices in a vehicle.
Anki et al, U.S. Pat. No. 4,403,155 discloses an improved wiring system in
which a connection box having a plurality of terminals, electrical
circuitry, and bus bars. Each bus bar provides a forked conductive path
between the circuitry and terminals and allows outside connectors to be
connected by wires in a one-to-one correspondence.
Mane et al, U.S. Pat. No. 4,689,718 discloses a programmable automobile
junction box housing printed circuit boards having receptacles for
receiving tabs depending from an elongated member which connect the
circuit pathways corresponding to vehicle options.
Sawai et al, U.S. Pat. No. 4,850,884 discloses a controller with wiring for
a vehicle. The controller has a junction block with at least one bus bar
circuit board on which harness branch circuits to which electrical devices
are connected.
Copeland et al, U.S. Pat. No. 4,864,154 discloses a solid state digital and
analog circuit which is connected between the vehicle battery and a
two-way radio, public address system, etc. in an emergency vehicle to
prevent the auxiliary electrical device from draining the battery. When
the ignition is turned off, a timer and relay in the circuit disconnects
the auxiliary device after a prescribed amount of time.
Tamer, U.S. Pat. No. 4,956,561 discloses a smart power connector for use in
a vehicular smart power multiplexing network Smart power connectors
connect the power network with various peripheral devices.
The present invention is distinguished over the prior art in general, and
these patents in particular by a D.C. power distribution and fuse panel
unit which facilitates installation and trouble shooting of vehicle
auxiliary electrical equipment such as two-way radios, sirens, computer
mobile data terminals, and mobile phones in police and other emergency
vehicles. The unit is installed beneath the dash of a vehicle or other
location inside the vehicle and is connected to the battery by a single
wire which passes through the firewall, and is joined to the ignition
circuit by a second wire connected to a suitable point such as the
existing vehicle fuse block. The unit is supplied with a constant source
of positive D.C. voltage, and also with ignition voltage when the vehicle
ignition switch is turned on. The unit contains solid state circuitry
including relay circuits, timer circuit, and has a plurality of fused
power output terminals including constant power, ignition controlled
power, and delayed power shut-off terminals for connecting various
auxiliary electrical devices having different power disconnect
requirements, and may also have a plurality of individual fused
input/output circuits. The unit provides a common power distribution
module for connecting and supplying power to various types of auxiliary
electrical equipment according to their particular requirements. The unit
may also have a test switch to speed up the delayed shut-off sequence and
allow rapid testing and trouble shooting.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a D.C. power
distribution and fuse panel unit which is easily and quickly installed in
vehicles to connect auxiliary electrical equipment such as two-way radios,
sirens, computers, and mobile phones and requires only a single power lead
to pass through the vehicle firewall for connection to the battery.
It is another object of this invention to provide a D.C. power distribution
and fuse panel unit for installation in vehicles to connect auxiliary
electrical equipment such as two-way radios, sirens, computers, and mobile
phones which is controlled by the vehicle ignition switch.
Another object of this invention is to provide a D.C. power distribution
and fuse panel unit for installation in vehicles to connect auxiliary
electrical equipment such as two-way radios, sirens, computers, and mobile
phones which is controlled by the vehicle ignition switch and has a
delayed shut-off.
Another object of this invention is to provide a D.C. power distribution
and fuse panel unit for installation in vehicles to connect auxiliary
electrical equipment such as two-way radios, sirens, computers, and mobile
phones which combines all the electrical power connections in a single
unit regardless of whether the electrical device requires constant power,
ignition controlled on/off or delayed shut-off.
Another object of this invention is to provide a D.C. power distribution
and fuse panel unit for installation in vehicles to connect auxiliary
electrical equipment such as two-way radios, sirens, computers, and mobile
phones which simplifies trouble shooting of the electrical circuits and
replacement of blown fuses.
Another object of this invention is to provide a D.C. power distribution
and fuse panel unit for installation in vehicles to connect auxiliary
electrical equipment such as two-way radios, sirens, computers, and mobile
phones which contains all the fuses for the externally controlled
electrical circuits in a single unit and utilizes plug-in type fuses and
quick disconnect type plugs for all connections.
A further object of this invention is to provide a D.C. power distribution
and fuse panel unit having a plurality of individual in/out fused circuits
for externally powered devices.
A still further object of this invention is to provide a D.C. power
distribution and fuse panel unit for installation in vehicles to connect
auxiliary electrical equipment such as two-way radios, sirens, computers,
and mobile phones which simple in construction, economical to manufacture,
and rugged and reliable in operation.
Other objects of the invention will become apparent from time to time
throughout the specification and claims as hereinafter related.
The above noted objects and other objects of the invention are accomplished
by a D.C. power distribution and fuse panel unit which facilitates
installation and trouble shooting of vehicle auxiliary electrical
equipment such as two-way radios, sirens, computer mobile data terminals,
and mobile phones in police and other emergency vehicles. The unit is
installed beneath the dash of a vehicle or other location inside the
vehicle and is connected to the battery by a single wire which passes
through the firewall, and is joined to the ignition circuit by a second
wire connected to a suitable point such as the existing vehicle fuse
block. The unit is supplied with a constant source of positive D.C.
voltage, and also with ignition voltage when the vehicle ignition switch
is turned on. The unit contains solid state circuitry including relay
circuits, timer circuit, and has a plurality of fused power output
terminals including constant power, ignition controlled power, and delayed
power shut-off terminals for connecting various auxiliary electrical
devices having different power disconnect requirements, and may also have
a plurality of individual fused input/output circuits. The unit provides a
common power distribution module for connecting and supplying power to
various types of auxiliary electrical equipment according to their
particular requirements. The unit may also have a test switch to speed up
the delayed shut-off sequence and allow rapid testing and trouble
shooting.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an electrical schematic diagram showing a prior art wiring
circuit for the connection of auxiliary electrical equipment wherein the
auxiliary electrical devices are connected direct to the battery.
FIG. 2 is an electrical schematic diagram showing a prior art wiring
circuit for the connection of auxiliary electrical equipment wherein the
auxiliary electrical devices are connected to the battery through a relay,
or through a relay and timer combination.
FIG. 3 is an electrical schematic diagram of the D.C. power distribution
and fuse panel unit in accordance with the present invention wherein the
unit is connected to the battery by a single lead and the ignition system
at the fuse block by a second lead and distributes power to the auxiliary
electrical devices through a plurality of fused terminals.
FIG. 4 is an electrical schematic diagram of the electrical circuitry of
the D.C. power distribution and fuse panel unit in accordance with the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The utilitarian features of the present invention are best understood when
compared with conventional prior art methods of installation and
connection of vehicle auxiliary electrical equipment. Therefore, a brief
discussion of the prior art methods follows. In the following examples,
the auxiliary equipment include a two-way radio, a siren, a computer
mobile data terminal (MDT), a radar unit, and a light bar.
FIG. 1 illustrates a typical prior art wiring circuit for the connection of
auxiliary electrical equipment wherein the auxiliary electrical devices
are connected "hot" or direct to the battery. In this installation it can
be seen that each piece of auxiliary electrical equipment requires one or
more power leads L that usually have an in-line fuse holder F spliced into
the wire, and each wire must be passed through the firewall of the vehicle
to reach the auxiliary equipment. This type of installation requires the
operator to physically turn off each piece of equipment separately, and
often results in a dead battery when the operator forgets to turn the
equipment off.
FIG. 2 illustrates typical prior art wiring circuits for the connection of
auxiliary electrical equipment wherein the auxiliary electrical devices
are connected to the battery through a relay R, or through a delayed
shut-off relay R and timer T combination. In these types of installations,
each piece of auxiliary electrical equipment and the relay R or relay and
timer T combination require one or more power leads L that usually have an
in-line fuse holder F spliced into the wire, and each wire must be passed
through the firewall of the vehicle to reach the auxiliary equipment.
Fewer wires are required to be passed through the firewall if the relay R
and timer T are mounted under the dash rather than under the hood. These
types of installations also require the vehicle ignition switch to be
turned on (keys in the vehicle) to operate the equipment, and the delayed
shut-off relay and timer combination keeps all equipment active during the
shut-off delay.
Referring now to FIG. 3, the wiring circuit of the present D.C. power
distribution and fuse panel unit 10 is shown. The D.C. power distribution
and fuse panel unit 10 (described in detail hereinafter) is installed
beneath the dash of the vehicle and is connected to the battery by a
single wire lead L1 which is passed through the firewall, and joined to
the ignition circuit by a second wire lead L2 connected to a suitable
point such as the existing vehicle fuse block. The first wire lead L1
connected with the battery supplies the unit 10 with a constant source of
positive D.C. voltage, and the second wire lead L2 supplies the unit with
ignition voltage only when the vehicle ignition switch is turned on. A
printed circuit board in the unit 10 contains solid state circuitry
including relay circuits, a timer circuit, a plurality of individual fused
input/output circuits, and a testing circuit (described below). The
various auxiliary electrical devices are connected to the unit 10 through
a plurality of fuse holders and power output connectors mounted on the
circuit board. The fused power outputs include; fused outputs providing
constant power, fused outputs providing ignition controlled power, and
fused outputs providing delayed power shut-off, and a plurality of
individual input/output fused circuits for externally powered devices,
such as a light controller for a light bar.
Thus, it can be seen that the present D.C. power distribution and fuse
panel unit 10 is installed quickly and easily and requires only a single
wire to be passed through the firewall and provides a common power
distribution module for connecting and supplying power to various types of
auxiliary electrical equipment according to their particular requirements.
The present D.C. power distribution and fuse panel unit 10 also provides a
test switch (described below) which speeds up the delayed shut-off
sequence and allows rapid testing and trouble shooting.
Referring now to FIG. 4 of the drawings by numerals of reference, the
circuitry of the D.C. power distribution and fuse panel unit 10 is shown.
The circuitry of the unit 10 is contained on a printed circuit board 11
and all the components and fuse holders are mounted on the circuit board.
The circuit has a battery D.C. input terminal 12 which is connected to the
positive terminal of the existing vehicle battery to provide a constant
source of positive D.C. voltage, and an ignition voltage input terminal 13
which is connected to a suitable point that is energized by the ignition
circuit such as the existing vehicle fuse block to provide a source of
positive D.C. voltage only when the vehicle ignition switch is turned on.
The battery D.C. input terminal 12 is connected by lead 14 to one side of
the normally open contacts of a delayed shut-off power relay RLY1.
Constant voltage output terminals 15 and 16 are connected with the battery
D.C. input terminal 12 through lead 17 and fuses F1 and F2. The constant
voltage output terminals 15 and 16 become hot (supplied with voltage) as
soon as the battery connection is made and remain hot at all times.
Delayed shut-off power voltage output terminals 18 and 19 are connected to
the other side of the normally open contacts of relay RLY1 through lead 20
and fuses F3 and F4. The delayed shut-off power voltage terminals 18 and
19 become joined to the battery D.C. voltage input terminal 12 through
leads 20 and 14 to provide power upon closure of the contacts.
One side of the coil of relay RLY1 is grounded and the other side of the
coil is connected by lead 21 to the collector of a transistor Q1. A diode
D1 and capacitor C1 connected in parallel with the coil of relay RLY1
provide a voltage surge protection circuit for transistor Q1 when the
magnetic field collapses across the coil of relay RLY1.
The ignition voltage input terminal 13 is connected by lead 23 to one side
of the coil of an ignition controlled relay RLY2 through a voltage surge
protection circuit consisting of diode D2 and capacitor C2 which are
connected in parallel across the coil of relay RLY2. The other side of the
coil of relay RLY2 is grounded. The lead 23 is joined to lead 22 between
the input terminal 13 and the fuse F5. The ignition voltage input terminal
13 is also connected by lead 22 to the voltage divider resistors R2 and R5
through series connected circuit protection fuse F5 and current limiting
resistor R1, and through lead 26 to the reset terminals of a counter U1
and flip-flop U2 (described below). The divider resistors R2 and R5
prevent small pulses of foreign voltage on the vehicle ignition input from
triggering the high impedance reset terminals of U1 and U2. The leads 24,
25, and 26 are joined to lead 22 between the resistors R1 and R2.
Ignition controlled power output terminals 29 and 30 are connected to one
side of the normally open contacts of the relay RLY2 through lead 31 and
fuses F6 and F7. The other side of the contacts of relay RLY2 are
connected to the D.C. voltage input terminal 12 by lead 32 connected to
the lead 14. The ignition controlled power output terminals 29 and 30
become joined to the battery D.C. voltage input terminal 12 through leads
14 and 32 upon closure of the contacts when the ignition is turned on to
provide ignition controlled power.
Although two power output terminals of each type have been shown, it should
be understood that any number of power output terminals and fused
input/output circuits (described below) may be provided as indicated by
dashed lines.
The timing circuitry includes a 14-stage binary ripple counter U1 (such as
a CD4060 integrated circuit CMOS chip), a JK flip-flop U2 (such as a
CD4027 integrated circuit CMOS chip), and a double-pole double-throw test
switch SW1. The output of counter U1 and the clock input of JK flip-flop
U2 are joined by lead 32. Operating voltage from the battery D.C. voltage
input terminal 12 is provided to the voltage inputs of counter U1 and flip
flop U2 through lead 14 and lead 34 through circuit protection fuse F8 and
current limiting resistor R6 and through lead 35 to voltage regulator
zener diode D4 and filter network capacitors C5 and C6.
The armature of the double-pole double-throw test switch SW1 is connected
to the counter U1 through resistor R7. In a first or normal operating
position, the armature of the switch completes a circuit between two
terminals of the counter U1 through a capacitor C7 and resistor R8, and in
a second position, completes a circuit between the same two terminals of
the counter through a capacitor C8 and resistor R9.
The battery D.C. voltage input terminal 12 is connected by lead 14 to the
normally open contacts of the delayed shut-off power relay RLY1 and to the
emitter of transistor Q1 through leads 27 and 28. The collector of
transistor Q1 is connected to one side of the coil of relay RLY1 and the
voltage surge protection network diode D1 and capacitor C1 through lead
21. The other side of the coil of relay RLY1 and diode D1 and capacitor C1
are connected to ground.
A lead 36 connected between resistors R3 and R4 that are connected to the
base of transistor Q1 is connected to the collector of a second transistor
Q2. The emitter of the transistor Q2 is grounded. The base of the
transistor Q2 is connected by lead 37 to an output of flip flop U2 through
a resistor R10.
The power distribution and fuse panel unit 10 also has an input/output
fused circuit portion 38 consisting of a plurality of input terminals 39
connected to respective output terminals 40 by individual leads 41 having
fuse holders which receive plug-in type fuses F9-F16. The fused circuit
portion 38 may be used to provide fused output circuits for externally
powered devices such as a light controller that powers various different
functions of an overhead light bar.
OPERATION
The D.C. power distribution and fuse panel unit 10 is installed beneath the
dash of the vehicle or other suitable location inside the vehicle and the
battery D.C. input terminal 12 is connected to the battery by a single
wire which is passed through the firewall. The ignition voltage input
terminal 13 is joined to the ignition circuit by a second wire connected
to a suitable point such as the existing vehicle fuse block. The unit 10
is thus supplied with a constant source of positive D.C. voltage, and also
with ignition voltage only when the vehicle ignition switch is turned on.
The various auxiliary electrical devices are connected to the appropriate
fused power output terminals of the unit 10 corresponding to their
particular voltage on/off requirements, such as constant power, ignition
controlled power or delayed power shut-off.
For example, if the vehicle is equipped with a computer mobile data
terminal (MDT) it would be connected to one of the delayed shut-off power
output terminals 18 or 19, a device such as a two-way radio or radar unit
may be connected to a constant voltage output terminal 15 or 16, and a
siren may be connected to an ignition controlled voltage output terminal
29 or 30.
The constant voltage output terminals 15 and 16 are supplied with D.C.
voltage as soon as the battery connection is made and remain energized at
all times.
When the ignition is turned on, a positive voltage is applied to the coil
of ignition controlled relay RLY2 and the reset terminals of the counter
U1 and JK flip-flop U2 of the timing circuit. This closes the contacts of
relay RLY2 to provide ignition controlled voltage through fuses F6 and F7
to the ignition controlled output terminals 29 and 30, and the reset
terminals of the counter U1 and flip-flop U2 causing an output terminal of
the flip-flop U2 to supply voltage to the delayed shut-off power relay
RLY1 through transistors Q1 and Q2 and thereby closing the contacts of the
relay RLY1. Closing of the contacts of relay RLY1 supplies voltage to the
delayed shut-off power output terminals 18 and 19 through fuses F3 and F4.
When the ignition switch is turned off, the positive voltage is removed
from the coil of the ignition controlled relay RLY2 and the reset
terminals of the counter U1 and JK flip-flop U2 of the timing circuit.
This causes the contacts of relay RLY2 to open and thereby shut-off
voltage to the ignition controlled power output terminals 29 and 30 and
causes the counter U1 of the timing circuit to start its count routine.
After the predetermined amount of time has lapsed (for example, a minimum
of 1 hour), voltage is removed from the delayed shut-off power off relay
RLY1 through transistors Q1 and Q2 and the contacts of the relay RLY1
open. Opening of the contacts of relay RLY1 shuts off voltage to the
delayed shut-off power output terminals 18 and 19 after the predetermined
time period.
The double-pole double-throw test switch SW1 is used to speed up the delay
time of the timing circuit by changing the resistance and capacitance
values in the oscillator circuit of the counter U1 so that an operational
test can be completed in about one minute rather than the normal time
delay (for example 1 hour). When the test switch SW1 is in the normal
operating position a circuit is completed through resistor R7 and the
first pair of switch terminals and capacitor C7 and resistor R8, and when
moved to the test position, a circuit is completed through resistor R7 and
the second pair of switch terminals through capacitor C8 and resistor R9.
The fused circuit portion 38 of the power distribution and fuse panel unit
10 may be used to provide fused output circuits for externally powered
devices. For example, the leads of a light controller that powers various
different functions of a police vehicle emergency light bar may be
connected to the terminals of the individual fused circuits whereby each
circuit in the light bar would be provided with a fuse to protect the
light controller.
While this invention has been described fully and completely with special
emphasis upon a preferred embodiment, it should be understood that within
the scope of the appended claims the invention may be practiced otherwise
than as specifically described herein.
* * * * *
|
|
|
|
|
|
|
Description |
|
