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CLASS 363, ELECTRIC POWER CONVERSION
SYSTEMS
SECTION I - CLASS DEFINITION
This is a restricted class for conversion systems wherein
a single electrical source circuit is coupled to a single
electrical load circuit.
A. LOAD IN OUTPUT CIRCUIT
1. Load Defined By Its Characteristics:
This class provides for conversion systems as defined
the Glossary, below, even though the electrical load in
the output circuit is recited by its characteristics, e.g., an
inductive load, a load having negative current resistance
characteristic, etc.
2. Particular Load Device:
Systems wherein a particular load device is recited in
the output circuit are classified with the particular art
even though the load device is recited by name only,
e.g., a motor, an electrical furnace, etc. A partial list of
such art systems is set forth under References to Other
Classes, below.
3. What This Class Does Not Provide For:
This class does not provide for systems having a plural-
ity of load devices whether the load devices are in dif-
ferent output circuits or in the same output circuit,
except where the plural load device in a single output
circuit are similar type loads. Therefore, if there are a
plurality of diverse load devices in a single output cir-
cuit, even though recited only by their characteristics,
e.g., a high inductive load and a low inductive load, then
the system is excluded from this class.
B. CONVERSION SYSTEMS INCLUDING VOLT-
AGE MAGNITUDE AND/OR PHASE CONTROL
Conversion systems of the type classified herein are
included in this class, even though they include voltage
magnitude and/or phase control means.
SECTION II - LINES WITH OTHER CLASSES
AND WITHIN THIS CLASS
B. CONVERSION SYSTEMS HAVING PLURAL
INPUT AND/OR PLURAL OUTPUT CIRCUITS
1. What This Class Excludes:
This class excludes systems having a plurality of either
electrical source (input) circuits (see below with refer-
ence to polyphase systems) or output circuits. Where
the system including the plurality of input and/or output
comprises or is part of an art device, classification is
with the art device. For other such systems, see Refer-
ences to Other Classes, below.
2. Alternate Input or Load Systems
If the system can operate with only one input and one
output circuit at a time, even though there might be an
alternate input or output circuit, classification is in this
class (363). If the system contemplates that more than
one input or output circuit will be used concurrently at
any time, the system is excluded from this class and
pointed out in 1 above. Also, see 3 below, with refer-
ence to polyphase systems.
3. Polyphase Systems
Although this class excludes systems having a plurality
of input or output circuits, systems wherein the input
circuit or the output circuit is a single polyphase circuit
are considered to be systems having a single input or
output circuit and are included in this class.
a. A single polyphase circuit is defined as a polyphase
circuit which either does not have significantly different
sources or significantly different load devices or load
circuits for its several phases.
b. Plural Single Phase Sources To Make Polyphase:
Systems wherein a plurality of single phase sources are
combined to produce a single polyphase output are
excluded from this class. See References to Other
Classes, below.
c. Polyphase From Single Phase:
This class includes systems having a single phase source
circuit where phase converter means are used to produce
a polyphase output. Where impedances are used for this
purpose, see Subclass References to the Current Class,
below.
C. CONVERSION SYSTEMS NOT INCLUDED IN
THIS CLASS
1. The conversion systems not included in this class for
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CLASSIFICATION DEFINITIONS
April 2003
the most part relate to the communications arts. They
include such converters as oscillators, modulators,
demodulators, detectors, amplifiers, repeaters, filters,
pulsing systems, wave transmission systems, etc. Many
of these excluded systems, such as modulators, amplifi-
ers, detectors, include means to control an electric cur-
rent or potential of one character, such as direct or
alternating current, by means of a control signal so as to
produce a current or potential of another character. For
example, in an amplifier system using an electronic tube
with a source of direct current connected to the anode,
the alternating current in the grid circuit controls the
electronic tube so that the flow of direct current is varied
to produce a pulsating current in the output. Also in
some of these systems, such as some types of detectors,
alternating current modulated by a signal is passed
through a rectifying system so as to produce in the out-
put circuit a pulsating direct current representative of
the signal. For the lines between some of the excluded
systems and this class, see the following sections. Also,
for a partial list of such converters and their classifica-
tion, see Related Art below.
It is common practice in the communications arts to
refer to a signal or control circuit as an input circuit
and the claims might recite -- --conversion of one fre-
quency to another where the first frequency is in fact
only a signal or control for controlling another electrical
source circuit which is the source of energy for produc-
ing the second frequency. In this class, the input circuit
is the circuit to which the energy is applied which is to
appear in the output circuit.
Systems which include Electricity-Heat-Electricity Con-
version are classified elsewhere. Lines and Networks
which include frequency conversion are classified else-
where. See References to Other Classes below.
2. Pulse Forming Circuits:
Systems designed to produce a plurality of discrete
pulses similar to the pulses used in radar systems by
conversion of electrical energy will be found in a num-
ber of other classes. Some of these classes are found in
References to Other Classes, below.
3. Amplifiers in Class 330, and the Conversion Systems
of This Class (363):
Systems which are designed to control a local source of
energy by means of a control wave so as to produce an
output which is either an enlarged, diminished or identi-
cal copy of the control wave of the type used in commu-
nication systems are classified as amplifiers in Class
330. In such systems, the control wave is not the source
of power for the system.
4. Oscillators In Class 331 and Conversion Systems Of
This Class (363):
a. Converting Direct to Alternating Current:
Converters for converting direct to alternating current
wherein the system is self-controlled are classified in
Class 331, except in those cases wherein the control
involves circuit making and breaking, or wherein a
resistor is mechanically varied. Where the system is
such that conversion may be either way, i.e., A.C. to
D.C. or D.C. to A.C. classification is in this class (363).
In those cases wherein the conversion is A.C. to D.C.
classification is in this class (363). The usual art in Class
331, will have a tuned circuit for determining the fre-
quency of the resulting alternating current. However, the
art in Class 331 also includes oscillators using resis-
tance-inductance and resistance-capacity circuits (e.g.,
relaxation oscillators) which are self-controlled. Some
of the oscillation generators in Class 331 are designed to
produce pulse waves. Also, see the reference to Class
315 in References to Other Classes, below, for a refer-
ence to the systems closely analogous to oscillation gen-
erators in Class 315.
b. Oscillators with Alternating Power Supply:
Self-controlled oscillatory circuits which have an alter-
nating current source of supply are classified as oscilla-
tion generators elsewhere. See References to Other
Classes, below.
c. Oscillators with Rectifier in Output Circuit:
Where the output of an oscillator is rectified, the overall
system is a conversion system for this class (363). See
Subclass References to the Current Class, below.
5. Harmonic Generators, Frequency Multipliers in
Class 327 and Class 331:
Systems designed to produce an output alternating cur-
rent of a frequency (f
1
), from an alternating current hav-
ing a frequency (f
2
) may be used as frequency
multipliers or frequency dividers. In event the output
frequency had definite harmonic relation to the fre-
quency (f
1
), (f
1
is a multiple of f
2
) the system is a har-
monic generator. Where the output frequency is a
submultiple of the frequency (f
1
) the system is a fre-
quency divider. Included as multiples are fractions such
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CLASSIFICATION DEFINITIONS
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as three-halves and as submultiples are fractions such as
two-thirds.
If the system includes an electronic tube of type having
a control means (e.g., grid) as the converting means and
the source of power (e.g., anode supply) is A.C. or D.C.
and the frequency of the output circuit is a multiple of
the frequency applied to the control circuit, classifica-
tion is elsewhere; for cascaded oscillator systems of the
frequency multiplying type, and for oscillators com-
bined with output coupling networks of the harmonic,
producing or selecting type classification is also else-
where. If the frequency of the output circuit in such
electronic tube systems is a submultiple of the fre-
quency app