Title of Invention

MAGNETIC GEARING OF PERMANENT MAGNET BRUSHLESS MOTORS

Abstract This invention relates to the magnetic gearing of permanent magnet brushless motors. In accordance with this invention, there is provided a permanent magnet brushless 3-phase motor comprising of winding R, Y, B each provided into a plurality of sections (1-5) and switch means (S1-S12) for selectively connecting the section of the respective winding e.g. R in series and/or parallel with all other sections of that winding R. Control means are provided for actuating the switch means (S1-S12) to connect the winding sections (1-5) in different configurations whilst the motor is running to alter the speed/torque characteristics of the motor.
Full Text

This invention relates to the magnetic gearing of permanent magnet brushless
motors.
Permanent magnet brushless motors are known which are capable of providing
variable speed outputs. The motor characteristics are linear, generating high torque at low
speeds and high speed at low torque levels.
In certain applications, the range of speed and torque characteristics of a particular
motor may not be sufficient to cover the desired range, even though the output power of the
motor may be sufficient. In such circumstances two options are available. Firstly, a more
powerful motor could be used to cover the entire range or secondly, mechanical gears could
be provided for the motor. Both of these methods add cost and weight to the system.
Canadian Patent Application No. 2341095 discloses an alternative to the above-
mentioned methods which uses a technique in which the speed and torque can be varied
inside the motor and the only additional item required is a switching circuit. A prerequisite of
this technique is that the stator coils of the motor must be segmented into at least two or more
sections, which are evenly or perhaps unevenly distributed throughout the stator slots. The
switching circuit can then be used to change the number of coil segments which are connected
to the supply. Such an arrangement utilises the control of the induced back electromotive
force (back emf) to control the speed by selectively altering the number of conductors which
are connected to the supply. This in effect also alters the torque with changing speed of the
motor.
In the main embodiment of Canadian Patent Application No. 2341095, each of the
motor windings comprises a plurality of series-connected sections provided by tappings in the
winding, which can be selectively connected across the supply. With just one of the coil
segments connected across the supply, the motor will produce a high speed but a low torque.
However, with a higher proportion of coils connected in series across the supply, the motor
will produce a lower speed at the same torque. In this manner, the speed but not the torque of
the motor can be varied by selectively connecting the windings in series.

In an alternative embodiment, each of the motor windings comprises a plurality of
parallel-connected sections, which sections can be selectively connected in parallel across the
supply. With just one of the coil segments connected across the supply, the motor will
produce a high speed but a low torque as previously described. However, with a higher
proportion of coils connected in parallel across the supply, the motor will produce high torque
at the same speed. In this manner, the torque but not the speed of the motor can be varied by
selectively connecting the windings in parallel.
A disadvantage of either arrangement is that sections are redundant when running
the motor during some configurations and thus copper(I2R) losses will be higher because the
cross-sectional area of copper utilised decreases as the number of active sections decreases.
Also, the presence of redundant sections means that the net resistance of the coils is not
optimised in all configurations and hence the supply current or voltage has to be controlled to
avoid damaging the connected coils. Since speed and torque are functions of the current, any
limitation of the current affects the performance of the motor.
In most situations, the supply current to the motor is limited (for example in
domestic mains to 13 amps), and thus the attainable speed and torque will not be optimised
when some coils are out of circuit.
We have now devised a permanent magnet brushless motor which alleviates the
above-mentioned problem.
In accordance with this invention, there is provided a permanent magnet brushless
motor comprising a winding divided into a plurality of sections and switch means for
selectively connecting the sections of the winding in one of a plurality of different
configurations, wherein each section is connected in series and/or parallel with all other
sections of the winding.
The switch means can then be used to change magnetic gears, by changing the
configuration of the coil segments in series, parallel or a combination of both, which are

connected to the supply. We call such an arrangement magnetic gearing because it utilises the
control of the induced back electromagnetic force (back emf) to control the speed by
selectively altering the winding configuration which are connected to the supply. This alters
the torque with changing speed of the motor.
In contrast to known methods of varying the speed or torque by coil manipulation,
the present invention is distinguished in that all of the winding segments contribute towards
the motor operation no matter which section configuration is being employed. In this manner,
all of the available copper is utilised at all times, thereby keeping the copper loss of the motor
to a minimum.
The advantage of utilising all of the winding sections is the reduction of the motor's
copper loss. Normally the stator slots are packed with as much copper wire as possible, either
by maximising the number of turns, or by maximising the wire diameter (if the number of
turns have been predetermined for the design). In this manner the cross-section area of copper
is maximised for the slot, so that the resistance of the coils is kept to a minimum. Hence the
copper loss for the motor will always be kept to a minimum.
In a first configuration, the switch means is preferably arranged to connect all of the
winding sections in parallel. In this configuration at a given current I, the motor is able to
reach high speeds at relatively low torque levels.
In a second configuration, the switch means is preferably arranged to connect all of
the winding sections in series. In this configuration at the same current I, the motor is only
able to deliver high levels of torque at relatively low speeds.
In a third configuration, the switch means is preferably arranged to connect some of
the winding sections in parallel, with at least one other section being connected in series with
the parallel-connected sections. In this configuration at the same current, the motor is able to
reach speeds between that of the first and second configurations and deliver a torque between
the first and second configurations.

In order to further vary the speed v torque characteristic of the motor, the voltage
applied to the winding may be pulse-width modulated, for example using said switch means.
The speed v torque characteristic of the motor may also be varied by rapidly
switching the winding sections between different configurations to obtain a characteristic
intermediate that of the configurations between which the windings are switched.
Preferably the switch means is able to vary the configuration of the winding
connections whilst the motor is running, in accordance with predetermined operating
parameters.
Preferably, the switch means is able to vary the configuration of the winding
connections whilst the motor is running, in accordance with the output of means for sensing
an operating parameter of the motor such as the current, voltage, speed or torque, or in
accordance with the output of means for sensing an operating parameter of the article being
driven by the motor such as velocity. In the case of a multi-phase motor having a plurality of
windings, the switch means may vary the configuration of the winding connections of a
conducting phase whilst the motor is running, in accordance with the back emf measured
across the winding of non-conducting phase or a section thereof.
Alternatively, the switch means is able to vary the configuration of the winding
connections in accordance with time or an operating cycle or program.
Alternatively, means may be provided for manually changing the configuration of
the winding connections.
Preferably all of the sections of the winding are wound in parallel during assembly,
with the current preferably flowing through each section in the same direction.
One of the sections of the winding may comprise a different number of turns from
another section. Also, one of the sections of the winding may comprise a conductor having a
different cross-sectional area than the conductor of another section.

An embodiment of this invention will now be described by way of an example only
and with reference to the accompanying drawings, in which:
Figure 1 is a schematic diagram of one phase of a 3- phase permanent magnet
brushless motor in accordance with the present invention;
Figures 2 to 6 are schematic diagrams showing various connections of sections of
the motor of Figure 1 ;
Figure 7 is a table showing the switch states of the motor of Figure 1 with reference
to the connections of Figures 2 to 6;
Figure 8 is a graph of speed v torque for the connections of Figures 2 to 6; and
Figure 9 is graph of speed v torque to illustrate how the ideal motor characteristics
for a washing machine can be achieved using the motor of Figure 1.
Referring to Figure 1 of the drawings, there is shown a 3-phase permanent magnet
brushless DC motor comprising three star-connected phases R, Y, B 18 slots, 12 poles and a
slot pitch of 1. The stator outer diameter, inner diameter and length are 110mm, 55 mm and
75mm, respectively. The air gap is 0.5mm, the magnet width and thickness are 10mm and 4
mm, respectively.
Each phase comprises a winding having, for example, five conductors or so-called
sections 1-5 of 0.63mm enamelled copper which are co-wound in parallel through the relevant
stator slots of the motor. The supply voltage to the motor is 180 volts DC.
The first end of the first section 1 of one phase R is connected to the first ends of the
first sections of the other two phases Y, B. The first end of the first section of the phase R is
also connected to the first end of the second section 2 of that phase R via a switchSl.

Likewise, the first ends of the other sections 3,4, 5 are connected to adjacent sections via
respective switches S2, S3, S4.
Similarly, the second end of the first section 1 of the phase R is connected to the
second end of the second section 2 of that phase R via a switch S9. Likewise, the second ends
of the other sections 3,4, 5 are connected to adjacent sections via respective switchesS10, S11,
S12. The second end of the fifth section 5 is also connected to the supply.
The second end of the first section 1 of the phase R is connected to the first end of
the second section 2 of that phase R via a switch S5. Likewise, the second ends of the other
sections2, 3,4 are connected to the first ends of adjacent sections via respective
switchesS6,S7,S8.
Referring to Figures 2,7 and 8 of the drawings, when the motor is initially started,
only the switches S5 to S8 are energised such that the sections 1-5 are connected in series.
In this manner the supply current flows through each series- connected section 1-5 in
the same direction with respect to each section's polar orientation (as indicated by the arrows
in Figure 1): it is imperative that this is always the case.
Had one of the sections (e. g. section 4) been oriented in the opposite direction, the
flux produced by section 4 would oppose the flux produced by sections 1,2, 3 and 5.
The torque of the motor is directly proportional to the current and, as long as the
starting torque is high enough to overcome the load attached to the motor, the rotor begins to
turn. This is accompanied by the generation of a back emf in the coils, which begins to cancel
out the supply voltage, so that the current available for the phase coils begins to reduce, as
does the torque produced by the motor.
The back emf, is directly proportional to the number of turns in the phase coils, the
magnetic flux produced by the permanent magnets, the number of permanent magnet pole

pairs and the angular speed of the rotor. Other factors, such as the interconnection between
the coils and the phases and the number of phases also affects the back emf generated.
The consequence of this behaviour is that, the motor will continue to accelerate until
the torque produced by it, equals the load. From this point on, the motor will continue to
rotate at a constant speed. If at any instance the load is altered, the motor will automatically
adjust its torque (and consequently, its speed) in order to balance the load.
The maximum speed that can be attained by a motor, occurs when there is no load
attached to the motor. Ideally, this occurs when the back emf generated in the phase coils is
equal to the supply voltage, at which instance there is no current flowing through the coils to
produce any torque ; this situation is referred to as the no load speed.
In reality, the back emf will always remain marginally lower than the supply voltage
(even at no load speed). This is because a small portion of power supply is used up in
overcoming frictional forces due to windage and the bearings, as well as iron losses of the
motor.
It is evident from the graph of Figure 8 that the motor is limited to performance
criteria within the speed v torque line for Figure 2. The graph indicates that the motor can
manage a maximum speed of 584 rpm and a maximum torque of 28.1 Nm. As a further
example, it can also provide torque of 8 Nm up to a maximum speed of approximately 400
rpm, or conversely, the motor running at 400 rpm, can provide up to a maximum torque of
approximately 8 Nm.
If the desired motor performance falls beyond the 10 amp line, for instance 14 Nm at
600 rpm, the motor parameters need to be altered in order to cater for the additional power
requirements.
Referring to Figures 3,7 and 8 of the drawings, the motor's performance can be
changed by altering the configuration in which all of the motor's windings are connected. By
energising the switches in accordance with Figure 7, sections 1 and 2 can be connected in

parallel and this parallel set is then connected in series with section 3,4 and 5 (which are
connected in series with one another).
It is evident from the graph of Figure 8 that the motor is now limited to performance
criteria within the speed v torque line for Figure 3. The graph indicates the motor will now
generate a no load speed of 725 rpm and a stall torque of 34.6 Nm.
Referring to Figures 4,7 and 8 of the drawings, the motor's performance can be
changed again by energising the switches in accordance with Figure 7, so that sections 1,2
and 3 are connected in parallel and this parallel set is then connected in series with sections 4
and 5 (which are connected in series with one another).
It is evident from the graph of Figure 8 that the motor is now limited to performance
criteria within the speed v torque line for Figure 4. The graph indicates the motor will now
generate a no load speed of 966 rpm and a stall torque of 46.1 Nm.
Referring to Figures 5,7 and 8 of the drawings, the motor's performance can be
changed again by energising the switches in accordance with Figure 7, so that sections 1,2, 3
and 4 are connected in parallel and this parallel set is then connected in series with section 5.
It is evident from the graph of Figure 8 that the motor is now limited to performance
criteria within the speed v torque line for Figure 5. The graph indicates the motor will now
generate a no load speed of 1449 rpm and a stall torque of 69. 0 Nm.
Referring to Figures 6,7 and 8 of the drawings, the motor's performance can finally
be changed by energising the switches in accordance with Figure 7, so that sections 1,2, 3,4
and 5 are connected in parallel.
It is evident from the graph of Figure 8 that the motor is now limited to performance
within the speed v torque line for Figure 6. The graph indicates the motor will now generate a
no load speed of 2898 rpm and a stall torque of 136.7 Nm.

At first sight, one may consider that the best option would be to implement the
configuration of Figure 6 (i.e. all sections in parallel), since this choice yields the greatest
range in terms of both speed and torque. However, although the voltage supplied to all of the
configurations is the same (180 volts DC), the current varies from one configuration to the
next. In practical applications there will always be a current limit, for example most
household appliances are limited to 13 amps. Referring to Figure 8, if a notional 10 amp limit
is applied to each configuration, it will be seen that the maximum torque achievable by the
configuration of Figures 2 to 6 are 29.7, 23.7, 17.8, 11.9 and 5.9 Nm respectively. Thus, by
operating the switches to change between the various configurations, whilst keeping the
motor within the confines of the 10 amp limit, a performance can be achieved as shown in the
shaded area of the graph. Accordingly, it will be appreciated that a gearing system for the
motor can be provided by operating the switches, thereby allowing the motor to generate
higher torque (at low speed) and higher speed (with low torque) than would be possible with
any single configuration (with limited current supply). Thus, when the motor is initially
energised, all sections can be connected in series as shown in Figure 2, such that a high
starting torque is achieved well within the confines of the 10 amp limit.
The switches S1 to S12 can be relays or semiconductor devices. In the case of
semiconductor devices, a plurality of devices could be included in a single package.
Individual switches for example S1, S5 and S9 can be configured into a single mechanical or
electronic switch. In this case when 1 and 9 are ON, then 5 is OFF. When 5 is ON, then 1 and
9 are OFF.
This way only 4 switches will be required per phase instead of 12 switches.
Referring to Figure 9 of the drawings, there is shown a graph of the required speed v
torque curve 20 for a domestic washing machine superimposed onto the graph of Figure 8. At
present the required speed and torque are normally achieved by using induction motors
running at high speeds with appropriate mechanical gearing and drive belts, or by using a
large DC direct drive motor. However, it can be seen that the required range of speed and
torque can easily be achieved within the current confines using a reasonably sized direct drive
brushless DC motor in accordance with this invention.

It will be seen that the configurations of Figures 3 and 4 are not necessary to provide
the required speed v torque curve for a domestic washing machine and thus some cost savings
can be achieved by omitting some of the switches.
It should be noted that the multi-segmented coils within a single phase need not be
wound using the same wire diameter or the same number of turns, however, all the phases
must be wound in an identical manner. For instance, section 1 of every phase must be wound
with the same wire and have the same number of turns. Coil section 2 can have a different
number of turns and it can be wound using a different wire diameter to that of section 1, but
coil segment 2 of every phase must be identical and the same applies to all other segments.
It will be appreciated that whilst the embodiment hereinbefore described utilises 3-
phases, the invention applies to a motor having any number of phases. Furthermore, the
invention also applies to permanent magnet brushless synchronous motors, which have
similar speed torque characteristics.
The configurations discussed in Figures 2 to Figures 6 are not the only possible
combinations. For example, another possible combination is coil sections 1 and 2 connected
in parallel and coil sections 3 and 4 connected in parallel, the two parallel sets being
connected in series with one another and with the remaining section 5. This configuration will
produce the same motor characteristics as the arrangement shown in Figure 4.
Yet another configuration can be obtained by connecting sections 1,2 and 3 in
parallel and sections 4 and 5 in parallel and then connecting the parallel sets in series with one
another. This will yield motor characteristics that are the same as the one produced by the
configuration shown in Figure 5.
The number of speed-torque characteristics that can be obtained is dependent on the
number of winding sections provided (per phase), which is limited to some finite number.

The motor operates at its most efficient level when it is running as close as possible
to its no load speed. For this reason, it is undesirable to allow the motor to compensate for an
increase in load, by automatically reducing its speed (on the speed-torque characteristics line).
It would be far better to meet the demands of the increase in load through magnetic gearing,
so that the new torque level is achieved whilst the motor continues to run close to its no load
speed. However, in order to meet all possible torque levels (within the given range of the
motor) the motor would require an infinite number of magnetic gears and therefore, an
infinite number of winding sections and switches.
In an alternative embodiment, it is possible to achieve any speed torque curve in
between those obtained by altering the configuration of the windings by interchanging
between the two configurations very rapidly, so that the motor is not operating at the
characteristics of either configuration, but somewhere in between. The rapid switching
between the two configurations can be achieved by feeding a pulse width modulated (PWM)
signal to the switches (S1 to S12) and the duty cycle of the PWM is altered to achieve the
desired intermediate speed and torque.
For example, consider a first configuration with all winding sections connected in
parallel; this gear provides the highest speed the motor can achieve and therefore, it is the
highest gear. The next gear down from this, is achieved by connecting one of the winding
sections in series with the remaining parallel sections; this provides the next highest speed.
If the PWM has a duty cycle of l00%, the gear will change from the highest to the
next lower gear and remain there. Conversely, if a duty cycle of 0% (i.e. no signal) is chosen,
the motor will remain in the highest gear. Choosing a duty cycle between 0 and 100% will
yield a gear and consequently, a motor speed and torque between the highest two gears; i.e. an
intermediate gear.
If desired, the gearing can be switched directly between the highest gear (all sections
in parallel) and the lowest gear (all sections in series). The duty cycle of the PWM can then be
used to select a speed/torque characteristics anywhere in between the two extremes of the
motor performance.

However, the resolution and consequently, the accuracy with which a desired speed
can be achieved decreases as the full range of the gearing scale increases. This, to some extent
can be compensated by increase in PWM frequency.

WE CLAIM
1. A permanent magnet brushless motor comprising a stator winding (R) including a
plurality of winding sections (1-5) and switch means (s1-s12) for simultaneously
connecting all of the winding sections of the stator winding (R) in a selected one of a
plurality of different configurations, in which each winding section (1-5) is connected
in a different series and/or parallel configuration with all other said winding sections
(1-5), wherein means are provided for actuating said switch means (s1-s12) to
change the winding sections (1-5) between different connection configurations to
obtain respective motor characteristics, said means also being arranged to
repeatedly switch the winding sections (1-5) between two different connection
configurations to obtain a motor characteristic intermediate of those of the connection
configurations between which the winding sections (1-5) are repeatedly switched.
2. A permanent magnet brushless motor as claimed in claim 1, in which the switch
means (s1-s12) is arranged to connect all of the winding sections (1-5) of the stator
winding (R) in parallel.
3. A permanent magnet brushless motor as claimed in claim 1, in which the switch
means (s1-s12) is arranged to connect all of the winding sections (1-5) of the stator
winding (R) in series.
4. A permanent magnet brushless motor as claimed in claim 1, in which the switch
means (s1-s12) is arranged to connect some of the winding sections (1-5) of the
stator winding (R) in parallel, with at least one other winding section (1-5) being
connected in series with the parallel-connected sections (1-5).
5. A permanent magnet brushless motor as claimed in any preceding claim, in which
the voltage applied to the winding sections (1-5) of the winding (R) is pulse-width
modulated.
6. A permanent magnet brushless motor as claimed in claim 5, in which the voltage
applied to the winding sections (1-5) of the winding (R) is pulse-width modulated by
selectively energising said switch means (s1-s12).
7. A permanent magnet brushless motor as claimed in any preceding claim, wherein a
plurality of stator windings (R,Y,B) are provided for connecting to respective phases

of the supply, each winding comprising a plurality of winding sections (1-5) and
switch means (eg S1-S12) being provided for selectably simultaneously connecting
all of the winding sections of a given stator winding in a series and/or parallel
configuration with all other winding sections of that winding.
8. A permanent magnet brushless motor as claimed in any preceding claim, comprising
control means for actuating the switch means (s1-s12) to vary the configuration of the
winding sections (1-5) whilst the motor is running, in accordance with predetermined
operating parameters.
9. A permanent magnet brushless motor as claimed in claim 8, in which the control
means is able to vary the configuration of the winding sections (1-5) whilst the motor
is running, in accordance with the output of means for sensing an operating
parameter of the motor.
10. A permanent magnet brushless motor as claimed in claim 8, in which the control
means is able to vary the configuration of the winding sections (1-5) whilst the motor
is running, in accordance with the output of means for sensing an operating
parameter of the article being driven by the motor.
11. A permanent magnet brushless motor as claimed in claim 8, in which the control
means is able to vary the configuration of the winding sections (1-5) of a conducting
phase whilst the motor is running, in accordance with the back emf measured across
the winding of non-conducting phase or a section thereof.
12. A permanent magnet brushless motor as claimed in claim 8, in which the control
means is able to vary the configuration of the winding sections (1-5) whilst the motor
is running, in accordance with time or an operating cycle or program.
. 13. A permanent magnet brushless motor as claimed in claim 8, in which the control
means comprises means for manually changing the configuration of the
windingsections (1-5).
14. A permanent magnet brushless motor as claimed in any preceding claim, in which all
of the sections of the winding (R) are wound in parallel to each other.
15. A permanent magnet brushless motor as claimed in any preceding claim, in which
the sections (1-5) of the winding (R) are connected such that current flows through
each section (1-5) in the same direction.

16. A permanent magnet brushless motor as claimed in any preceding claim, in which
one of the sections (1-5) of the winding (R) of a given phase comprises a different
number of turns from another section (1-5) of the winding (R) of the given phase.
17. A permanent magnet brushless motor as claimed in any preceding claim, in which
one of the sections (1-5) of the winding (R) of a given phase comprises a conductor
having a different cross- sectional area than the conductor of another winding section
(1-5) of the winding (R) of the given phase.



ABSTRACT


MAGNETIC GEARING OF PERMANENT MAGNET BRUSHLESS MOTORS
This invention relates to the magnetic gearing of permanent magnet brushless motors. In
accordance with this invention, there is provided a permanent magnet brushless 3-phase motor
comprising of winding R, Y, B each provided into a plurality of sections (1-5) and switch means
(S1-S12) for selectively connecting the section of the respective winding e.g. R in series and/or
parallel with all other sections of that winding R. Control means are provided for actuating the
switch means (S1-S12) to connect the winding sections (1-5) in different configurations whilst
the motor is running to alter the speed/torque characteristics of the motor.

Documents:

01375-kolnp-2006 abstract.pdf

01375-kolnp-2006 claims.pdf

01375-kolnp-2006 description(complete).pdf

01375-kolnp-2006 drawings.pdf

01375-kolnp-2006 form-1.pdf

01375-kolnp-2006 form-2.pdf

01375-kolnp-2006 form-3.pdf

01375-kolnp-2006 form-5.pdf

01375-kolnp-2006 international publication.pdf

01375-kolnp-2006 pct form.pdf

01375-kolnp-2006-assignment.pdf

01375-kolnp-2006-correspondence others.pdf

01375-kolnp-2006-correspondence-1.1.pdf

01375-kolnp-2006-form-18.pdf

1375-KOLNP-2006-(05-07-2012)-CORRESPONDENCE.pdf

1375-KOLNP-2006-(26-02-2013)-CORRESPONDENCE.pdf

1375-KOLNP-2006-(28-03-2012)-ABSTRACT.pdf

1375-KOLNP-2006-(28-03-2012)-AMANDED CLAIMS.pdf

1375-KOLNP-2006-(28-03-2012)-DESCRIPTION (COMPLETE).pdf

1375-KOLNP-2006-(28-03-2012)-DRAWINGS.pdf

1375-KOLNP-2006-(28-03-2012)-EXAMINATION REPORT REPLY RECEIVED.pdf

1375-KOLNP-2006-(28-03-2012)-FORM-1.pdf

1375-KOLNP-2006-(28-03-2012)-FORM-2.pdf

1375-KOLNP-2006-(28-03-2012)-OTHERS.pdf

1375-KOLNP-2006-(28-03-2012)-PA-CERTIFIED COPIES.pdf

1375-KOLNP-2006-CANCELLED PAGES.pdf

1375-KOLNP-2006-CORRESPONDENCE OTHERS 1.2.pdf

1375-KOLNP-2006-CORRESPONDENCE-1.1.pdf

1375-KOLNP-2006-CORRESPONDENCE-1.2.pdf

1375-KOLNP-2006-CORRESPONDENCE-1.3.pdf

1375-KOLNP-2006-CORRESPONDENCE.pdf

1375-KOLNP-2006-EXAMINATION REPORT.pdf

1375-KOLNP-2006-FORM 18.pdf

1375-KOLNP-2006-GRANTED-ABSTRACT.pdf

1375-KOLNP-2006-GRANTED-CLAIMS.pdf

1375-KOLNP-2006-GRANTED-DESCRIPTION (COMPLETE).pdf

1375-KOLNP-2006-GRANTED-DRAWINGS.pdf

1375-KOLNP-2006-GRANTED-FORM 1.pdf

1375-KOLNP-2006-GRANTED-FORM 2.pdf

1375-KOLNP-2006-GRANTED-FORM 3.pdf

1375-KOLNP-2006-GRANTED-FORM 5.pdf

1375-KOLNP-2006-GRANTED-SPECIFICATION-COMPLETE.pdf

1375-KOLNP-2006-PA.pdf

1375-KOLNP-2006-REPLY TO EXAMINATION REPORT.pdf

abstract-01375-kolnp-2006.jpg


Patent Number 257064
Indian Patent Application Number 1375/KOLNP/2006
PG Journal Number 35/2013
Publication Date 30-Aug-2013
Grant Date 29-Aug-2013
Date of Filing 23-May-2006
Name of Patentee ELECTRONICA PRODUCTS LIMITED
Applicant Address CARDIFF BUSINESS TECHNOLOGY CENTRE, SENGHENNYDD ROAD, CARDIFF CF 24 4AY,
Inventors:
# Inventor's Name Inventor's Address
1 SHIRAZEE, NABEEL, AHMED 11 LISVANE STREET, CATHAYS, CARDIFF CF24 4LH
2 CHOUDHARY, PRAVEEN 32 MANOR STREET, HEATH, CARDIFF CF14 3PW
PCT International Classification Number H02K 3/28
PCT International Application Number PCT/GB2004/004512
PCT International Filing date 2004-10-22
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 0324785.5 2003-10-24 U.K.