Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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BACKGROUND OF THE INVENTION
This invention relates to arc welding apparatus
that is powered by an inductor alternator of a motor vehicle
and more particularly to such apparatus that is remotely
controllable to function as an auxiliary power unit.
Arc welding apparatus in mobile installations has
been employed advantageously in agricultural and other apply-
cations where welding repairs may be effected in the field.
This feature is of particular benefit where breakdown occurs
in agricultural equipment at a location remote from a repair
shop which may necessitate at least a temporary repair in
the field in order to permit transporting the equipment back
to the repair shop for a more permanent repair. Not only
does this reduce the down time of the broken down agricultural
equipment but it could also mean that an immediate field
repair may prevent further damage and could, often as not,
comprise a complete repair requiring no further attention at
the repair shop.
Another advantageous use to which a mobile arc
I welder is applied is that of using its power unit as a booster
supply to start motor vehicle engines under cold weather
conditions when a vehicle battery is virtually dead and
almost frozen from exposure. Under such circumstances, the
power unit of the arc welder is adaptable to operate also as a
battery charger that is capable of charging any battery in a
voltage range of from 6 to 24 volts at charging currents
ranging up to as much as 150 amperes.
Moreover, the auxiliary power unit of a mobile arc
welder is particularly well suited to perform as an emergency
power supply, providing an output that is readily capable
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of energizing resistive loads for operating incandescent spot
and floodlighting equipment as well as small appliances
such as hot plates, percolators, toasters and the like. It
is apparent, therefore, that these features are well suited
to other applications such as recreational activities which
means that a mobile arc welder and auxiliary power unit has
applications which may be encountered on a regular basis as
when camping or when working in remote areas.
Furthermore, it is known in the art that an arc
welder which operates from an inductor alternator provides a more
smooth, superior weld than that provided by standard welders
operating at low voltage and high current. This is due
directly to a high frequency component in the welding current.
A high frequency finished weld therefore presents a weld no-
squiring little, if any, manual burnishing to improve its
appearance.
Since individual components of the apparatus to
which this invention relates are well known to individuals
skilled in the art of mobile arc welders, and because the
circuit arrangement of a welding system is relatively simple,
it is likely that miniseries would tend to buy the required
components in kit form and personally install same in order
to effect a monitory savings. A mobile arc welding system in
kit form should therefore include components that are readily
installed using conventional hand tools that would normally
be in the possession of the user.
Moreover, a simple system design would permit ready
installation on motor vehicles, or motorized trailers. Since
in most instances the inductor alternator, which comprises a
major component of an arc welding system, will be employed
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in its conventional capacity as a source of charging voltage
for the vehicle battery, the system should be designed to
operate efficiently in the motor vehicle without having any
deleterious effect on standards set by original equipment
manufacturers for engine compartment components.
SUMMARY OF THE INVENTION
A principal objector the present invention is the
provision of a remotely controllable arc welder and combined
auxiliary power unit that will function in a 100~ duty cycle
mode, both as an arc welder and as an auxiliary power unit.
Another object of the invention is the provision
of such welder and power unit which is simple in design and
easily installed on a motor vehicle using conventional hand
tools.
Still another object of the invention is the pro-
vision of a remotely controllable arc welder and combined
auxiliary power unit capable of predetermined low and high
voltage outputs.
Yet another provision of the invention is such an
arc welder and power unit that is compatible with most motor
vehicles without deleterious effect on original equipment
manufacturers functional standards of engine compartment
components.
Still another object of the invention is the pro-
vision of a remotely controllable arc welder and combined
auxiliary power unit which is capable of functioning in either
a regulated or unregulated mode.
The known requirements for an efficient mobile arc
welder and combined auxiliary power unit, together with the
foregoing provisions, are substantially achieved by recourse
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to my invention which is a remotely controllable arc welder
and combined auxiliary power unit that comprises, an inductor
alternator adapted to be rotatable driven by an internal
combustion engine, the alternator having a stators winding
terminal, a pair of direct current output terminals, a
corresponding pair of battery terminals and a pair of field
winding terminals. Additionally, the arc welder and power
unit comprises throttle control means operably connected to
a carburetor of the engine for controlling the running speed
thereof, the throttle control means being communicable with
an intake manifold of the engine and responsive to a reduced
pressure thereat for increasing the engine running speed.
Valve means controllable communicating the throttle control
means with the manifold are also included with first switch
means for controllable enabling and disabling the valve means
whereby the alternator is rotatable driven through a prefer-
mined range of engine speeds for generating a corresponding
range of direct current voltages across the output terminals.
And second switch means interposed between corresponding ones
of at least one terminal of the pair of direct current output
terminals and the pair of battery terminals are controllable
to selectively connect together and disconnect the respective
terminals.
GRIEF DESCRIPTION OF THE DRAWINGS
. .
The invention will now be more particularly described
with reference to an embodiment thereof, shown by way of
example, in the accompanying drawing in which Fig. 1 is a
schematic diagram of a remotely controllable arc welder and
combined auxiliary power unit configured in accordance with
the present invention.
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
_
A preferred embodiment of the present invention is
illustrated in Fig. 1 in the form of a schematic diagram of
a remotely controllable arc welder and combined power unit
10. It will be observed that the unit includes an inductor
alternator 11 which is rotatable driven Vim a drive belt 12
from an internal combustion engine (not shown) of the motor
vehicle or a trailer with a like engine mounted thereon.
Although the unit 10 is operable with an inductor alternator
usually accompanying the engine, the circuit of Fig. 1 is
particularly well suited for use with a heavy duty alternator
that is capable of functioning in a lC0% duty cycle at an
output of 100 amperes and which has the capability of charging
any battery in a voltage range of from 6 to 24 volts at a
charging current up to 150 amperes. It has been determined
that a Chrysler Corporation, heavy duty alternator of the
type commonly used on their motor vehicles meets these require-
mints.
Since the alternator 11 is of a known type and does
not separately comprise a part of the present invention, it
is only illustrated diagrammatically in Fig. 1 with the various
terminals of the alternator being shown connected to other
components in the unit 10. In this regard it will be understood
that the alternator 11 includes a ground terminal 13 which is
common to a do output of the alternator as well as to
a stators winding. Thus, the second terminal of the do output
comprises a battery terminal 14 whereas the second terminal
of the stators winding comprises a stators terminal 15. Field
excitation for the alternator 11 is provided by means of a
conventional field winding therein which is connected to a
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pair of field terminals 16 and 17, the terminal 16 being
grounded to the same point as the terminal 13.
Field excitation current to the alternator 11~ is
normally applied to the field winding (not shown) via the
terminals 16 and 17. Two separate current sources are used
depending upon the mode in which the unit 10 is to function.
Thus, in the event that the unit is to be operated as an arc
welder having an output voltage in the range of from about
65 to 90 volts, the terminals 16 and 17 are connected directly
across the vehicle's battery 20 by way of one pole of a double
pole double throw function switch 21. Fig. 1 reveals that a
pole 22 is connected by way of a lead 23 to an ignition switch
24 of the vehicle and that connection to the terminal 17 is
made by way of a contact 25 when the switch 21 is set to its
boost or welding position. The second source of current is
similarly supplied by the battery 20 and is applied from a
positive terminal thereof through a known voltage regulator 26
and a coupling diode 27. The regulator 26 is of a known type
that is completely transistorized and which is manufactured
by the Motor craft Corporation as a model "A" regulator,
part No. Groucho features built-in short circuit pro-
section. In this circuit configuration, current slow through
the field winding of the alternator occurs via the terminals
16 and 17, and serially through the diode 27, the regulator 26
and a protective circuit breaker 28 to the positive terminal
of the battery 20.
A second pole 30 of the switch 21 is selectively
connectable to contacts 31 or 32 whereof which corresponds
to the position of the pole 22 when connected between the
contacts 29 and 25, respectively. Thus, when the switch 21
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is in the boost or welding position, the connection with
the contact 31 is broken so that the terminal 15 of the
alternator 11 is disconnected from the regulator 26. It
will be recalled that when the switch 21 is in the boost or
welding position, the full battery voltage is connected across
the terminals 16 and 17 causing a maximum field excitation
current through the field winding. This in turn produces a
maximum a voltage across the terminals 13 and 15. However,
since this maximum voltage could be injurious if applied to
the regulator 26, the switch 21 precludes this possibility by
disconnecting the terminal 15 from the regulator 26 as
described.
When the switch 21 is set to a battery charge post
lion, the terminal 15 is connected via the pole 30 and the
contact 31 to the regulator 26 to effect regulation of the
do output voltage appearing across the terminals 13 and 14.
Concurrently, the pole 22 engages the contact 29 and energizes
a field winding 32 of a solenoid switch 33. Consequently, a
pair of contacts 34 and 35 close, thereby connecting the
terminal 14 to the regulator 26 and through the breaker 28 to
the positive terminal of the battery 20. The fully regulated
output voltage from the alternator 11 is thus available to
maintain the charge of the battery 20.
The regulated output voltage across the terminals 13
and 14 is also available for charging other batteries. Thus,
the terminal 14, which is the positive terminal is connected
to the contact 34 via a welding cable 36. A like cable 37
leads from the contact 34 to a female connector 38. Contact
with the connector 38 is made via a corresponding male con-
nectar 39 and therefrom another like welding cable 40 leads
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to a holder 41 which is adapted to hold either a welding
rod or a clip type of connector snot shown) for connection
to the positive post of a battery hot shown) to be charged.
The corresponding negative post of the battery is grounded and
a spring clip issue connected via a welding cable 43 to a
male connector 44 that is connectable to a corresponding
female connector 45 which is also grounded.
When the switch 21 is set to its boost or welding
position, it will be recalled that the do output voltage
from the inductor 11 is unregulated. This mode provides,
therefore, the means for generating a range of direct current
voltages across the terminals 13 and 14 by controlling the
running speed of the vehicle's engine. Speed control is
effected by throttle control means 50 which is operably con-
netted to a carburetor 49 of the engine. A diagrammatic rep-
resentationof the control means 50 is seen to comprise throttle
linkage 51 that is connected intermediate a rotatable control
shaft 52 of a throttle valve 53 in the carburetor 49 and a
vacuum diaphragm 54 that is attached to a U bracket 59 in
fixed relation with the shaft 52. The linkage 51 comprises
a cable 55 that is slid ably disposed within a cable sleeve 56.
One end of the cable 55 is connected to a diaphragm plate off the
diaphragm 54 which is displaceable relative to thy shaft 52
such that movement of the diaphragm plate produces a Coors
pounding movement in the cable 55 which is translated to
rotary movement of the shaft 52. Although not shown it will
be understood that a return spring on the shaft urges same
to a closed condition so that the action of the diaphragm 54
will be such as to open the valve 53 thereby increasing
engine speed from a predetermined low speed that is set by
a linkage adjustor 60.
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The adjustor 60 comprises a cable bushing 61 having
a threaded end that is inserted through an aperture inn arm
of the bracket 59 opposite the diaphragm 54 and a flanged
end that is held in resiliently spaced relation with the
aperture bracket arm by means of a coil spring 62 that is
wrapped coccal with the long axis of the bushing 61 and
which is positioned between the flanged end and the bracket.
A wing nut 63 adjusts the position of the bushing relative
to the shaft 52. Since the threaded end abuts the sleeve 56,
relative movement of the bushing results in movement of the
sleeve 56 and corresponding rotary movement of the shaft 52.
Further rotation of the shaft 52, resulting in increased
engine speed, occurs via the cable 55 under movement of the
diaphragm 54.
Operation of the diaphragm 54 occurs when one side of the
diaphragm communicates with a suction or reduced pressure at
an intake manifold (not shown) of the engine. Reference to
Fig. 1 shows such a communication path as comprising a tube 65
leading from the low pressure side of the diaphragm to a vacuum
valve 66 and therefrom through a second tube 67 to a connector
68 on the carburetor which communicates with the reduced pros-
sure of the intake manifold. The valve 66 includes a field
winding 70 which, when energized, opens the valve 66 which in
turn operates the diaphragm 54.
One terminal of the winding 70 is shown connected to
the switch 24 through which connection is made to the positive
terminal of the battery 20. Energizing current to the winding
70 flows when the other terminal of the winding is grounded
as by a local single pole single throw switch 71. The
switch 71 would normally be mounted on a control panel located
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in an accessible position on the vehicle. Additionally,
the connectors 38 and 45 would be similarly mounted on the
panel to facilitate connection to the cables 40 and 43.
Remote control of the valve 66 is achieved by means
of a push button switch 72 that is mounted on the holder 41.
It will be observed that the switch 72 is connected via a
two-conductor control cable 73 to a plug 74 which, in turn,
is connectable to a jack 75 that is wired in parallel with
the switch 71. Accordingly, the winding 70 is readily actuated
by an operator to boost the output voltage from the alternator
11 as when arc welding or when connecting the holder 41 to
batteries being boosted. In either of these operating modes,
a do output voltage from the alternator 11 is unregulated and
varies directly with engine speed. At this time the switch 33
is open to disconnect the battery 20 from the alternator 11
The unit 10 is well adapted to rapidly recharge
batteries by setting the switch 21 from its normal charge
position in which an output voltage range from 14.2 to 14.8
volts is obtained to the boost position in which the alter-
NATO 11 output voltage varies according to engine speed to provide a voltage range of from about 6 volts at the low end
to a voltage in excess of 110 volts at the high end. An
appropriate setting of the throttle control means 50 will
achieve a desired voltage. A voltmeter 76 monitors the do
output voltage at the alternator 11 and may be used in setting
the engine speed as required. In this regard, lower voltages
capable of rapidly recharging any 6, 12 or 24 volt battery
system may be achieved merely be setting the adjustor 60
without actuating the diaphragm 54. Should a higher voltage
be required, as in welding, the diaphragm 54 may be actuated
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by operating the switch 72 in order to communicate the
suction side of the diaphragm with the reduced pressure at
the intake manifold. A momentary contact switch may be
used advantageously as the switch 72 whereby the diaphragm
54 will remain actuated only for as long as pressure is apt
plied to the switch to maintain the contacts thereof closed.
This feature is particularly advantageous in welding since a
higher welding voltage is required only on an intermittent
basis. Thus, operation of the switch 72 will increase engine
speed to provide a higher voltage only for as long as same is
required. Thereafter, release of the switch 72 will permit
the engine speed to drop to a predetermined low setting
to effect fuel conservation.
In order to power small appliances, external lighting
circuits and the like, a polarized receptacle 77 is connected
from ground to the terminal 14. In this application, a stable
output of 110 volts would likely be required and would be
achieved by actuating the diaphragm 54 using the switch 71 to
operate the valve 66.
As the unit 10 is switched from one operating mode
to another, excitation current flowing through the field
winding may be monitored by means of an ammeter 78 which is
connected between the terminal 16 and ground. Operating the
switch 21 to select operating modes could result in the
development of relatively high voltage transient pulses
appearing across the terminals 16 and 17 of the field winding.
Since the terminal 17 is connected to the regulator 26, it is
possible that the transient voltage could enter the regulator
and cause damage. This possibility is obviated, however, by
the diode 27 which presents a sufficiently high peak inverse
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I voltage rating to prevent component voltage breakdown
¦ induced by a transient voltage spike of large magnitude.
¦ It will be apparent to those skilled in the art
¦ that the embodiment heretofore described may be varied to
¦ meet particular specialized requirements without departing
¦ from the true spirit and scope of the invention disclosed.
¦ The foregoing embodiment is therefore not to be taken as
¦ indicative of the limits of the invention but rather as
as an exemplary structure of the invention which is described
by the claims appended hereto.
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