Field of the Invention:
The invention generally relates to a method and device for detecting throttle opening level
based on a throttle position sensor providing a fluctuating signal. The invention also relates to
a method and an ignition control device for controlling ignition of an internal combustion
engine based on a throttle position sensor providing a fluctuating signal.
Background of the Invention:
Throttle position sensor(s), which is generally a magnetic sensor such as a hall-effect sensor,
is provided in a vehicle to determine / detect position of a throttle value or in other words, a
throttle opening level.
Depending upon the positioning of the throttle position sensor in the vehicle, the throttle
position sensor provides signals from which, a detection unit has to determine the throttle
opening level. By way of example, if a single throttle position sensor is provided at a first
position in the vehicle, till the time the throttle position sensor continuously produces a LOW
signal, the throttle opening level is detected as being less than a predetermined throttle value
(let’s say 50%). Thus, once the throttle position sensor, starts producing a continuous
“HIGH” signal, the throttle opening level is detected as being greater than the predetermined
throttle value. By way of another example, if the single throttle position sensor is provided at
a second position in the vehicle, till the time the throttle position sensor continuously
produces a continuous “HIGH” signal, the throttle opening level is detected as being less than
a predetermined throttle value and once the throttle position sensor, starts producing a
continuous “LOW” signal,, the throttle opening level is detected as being greater than the
predetermined throttle value. In some places, the “LOW” signal may be alternatively referred
to as “OFF” signal and the “HIGH” signal may be referred to as “ON” signal.
Thus, from the above, it can be observed that while detection unit takes into consideration
positioning of the throttle position sensor in the vehicle and the type of signal (HIGH or
LOW) produced by the throttle position sensor, the throttle position sensor is expected to
continuously produce a first type of signal or a second the type of signal.
It has been observed that if the throttle position sensor receives a constant driving current, for
example, from a battery present in the vehicle, it produces the appropriate signals as
mentioned above. However, there are instances, when the signal produced by the throttle
position sensor is not appropriate. For example, if the throttle position sensor receives a
3
fluctuating driving current, for example, from an alternating current generator (ACG) having
a regulator-rectifier attached thereto, a fluctuating signal (or other an in-appropriate signal) is
produced. In many instances, determining / detecting the throttle opening level from the
fluctuating signal becomes difficult.
One of the reasons for providing a throttle position sensor (or in other words, determining /
detecting position of the throttle value or the throttle opening level), is to control ignition of
an internal combustion engine provided in the vehicle.
Documents such as JP-A- 6 137 241 (Inventors: Nakano Takatoshi et al.; Applicant: Yamaha
Motor Co Ltd) and JP-A- 57 068 558 (Inventor: Katada Hiroshi; Applicant: Hitachi Ltd)
disclose disposing plurality of throttle position sensors and controlling ignition timing of the
internal combustion engine on basis of outputs received therefrom.
Apart from the above, documents such as JP-A- 63 314 368 (Inventors: Sugiyama Masao et
al.,; Applicant: Mazda Motor) and EP Patent No EP 1,452,730 disclose disposing single
throttle position sensor and controlling ignition timing of the internal combustion engine on
basis of output from the single throttle position sensor. Although, controlling ignition of the
internal combustion engine based on output from single throttle position sensor may not be as
accurate as controlling ignition of the internal combustion engine based on output from
plurality of throttle position sensors, it may be cost effective and provide an ease in
manufacturing. Also, controlling ignition of the internal combustion engine based on output
from single throttle position sensor can provide for fairly accurate controlling of the internal
combustion engine. Thus, controlling ignition of the internal combustion engine based on
output from single throttle position sensor is an industrially attractive and a widely followed
option.
In cases where the signal produced by the throttle position sensor is of fluctuating nature, the
ignition control circuit can experience difficulties in controlling the ignition timing.
Hence, there is need to provide a method and a device that accurately detects a throttle
opening level based on fluctuating signal produced by the throttle position sensor. Also,
there is a need to provide a method and an ignition control device for controlling ignition of
an internal combustion engine based on a fluctuating signal produced by the throttle position
sensor.
4
Summary of the Invention:
In accordance with a first embodiment of the invention, there is provided a method for
detecting a throttle opening level of a throttle valve provided in a vehicle, said method
comprises the steps of receiving a throttle signal from at least one throttle position sensor
located at a first position, determining the throttle opening level as being less than a
predetermined value if (a) the throttle signal comprises more than one pulse in one rotation of
an alternating current generator and (b) value of “R” of the throttle signal is in excess of a
predetermined threshold value; R being defined as:
=

∗ 100.
In line with the first embodiment of the invention, there is provided an apparatus for detecting
a throttle opening level of a throttle valve provided in a vehicle, said apparatus comprises a
receiving unit for receiving a throttle signal from at least one throttle position sensor located
at a first position; and a determining unit for determining the throttle opening level as being
less than a predetermined value if (a) the throttle signal comprises more than one pulse in one
rotation of an alternating current generator and (b) value of “R” of the throttle signal is in
excess of a predetermined threshold value; R being defined as:
=

∗ 100.
In line with the first embodiment of invention, there is further provided a first method for
controlling ignition of an internal combustion engine said method comprises the steps of
receiving a throttle signal from at least one throttle position sensor located at a first position;
and providing a first control signal for controlling an ignition timing on basis of a first
characteristic, the first characteristics corresponding to throttle opening level being less than a
predetermined value, wherein the throttle opening level is determined to be less than the
predetermined value if (a) the throttle signal comprises more than one pulse in one rotation of
an alternating current generator and (b) value of “R” of the throttle signal is in excess of a
predetermined threshold value; R being defined as:
=

∗ 100.
In line with the first embodiment of invention, there is further provided an ignition
controlling device for controlling ignition of an internal combustion engine said ignition
controlling device comprises a receiving unit for receiving a throttle signal from at least one
5
throttle position sensor located at a first position; and a processing unit adapted to provide a
first control signal for controlling an ignition timing on basis of a first characteristic, the first
characteristics corresponding to throttle opening level being less than a predetermined value,
wherein the throttle opening level is determined to be less than the predetermined value if (a)
the throttle signal comprises more than one pulse in one rotation of an alternating current
generator and (b) value of “R” of the throttle signal is in excess of a predetermined threshold
value; R being defined as:
=

∗ 100.
Based on the positioning of the throttle position sensor, the signal thus produced can be either
indicative of the throttle opening level being less than the predetermined value or being
greater than the predetermined value. Thus, when the throttle position sensor is located at the
first position, satisfaction of (a) and (b) as described above, indicates the throttle opening
level being less than the predetermined value. On other hand, when the throttle position
sensor is located at the second position; and conditions (a) and (b) as described above are
satisfied, the throttle opening level is determined as being greater than the predetermined
value. Also, in such a case, a second control signal for controlling ignition timing on basis of
a second characteristic is provided, the second characteristics corresponding to throttle
opening level being greater than the predetermined value.
To further clarify advantages and features of the present invention, a more particular
description of the invention will be rendered by reference to specific embodiments thereof,
which is illustrated in the appended figures. It is appreciated that these figures depict only
typical embodiments of the invention and are therefore not to be considered limiting of its
scope. The invention will be described and explained with additional specificity and detail
with the accompanying figures.
BRIEF DESCRIPTION OF FIGURES:
These and other features, aspects, and advantages of the present invention will become better
understood when the following detailed description is read with reference to the
accompanying figures in which like characters represent like parts throughout the figures,
wherein:
Figure 1 illustrates a block diagram of an arrangement which is available in a vehicle;
6
Figure 2, illustrates output produced by prior art throttle position sensor provided at first
position in the vehicle, when the throttle opening is less than a predetermined throttle opening
level and when the throttle position sensor receives a fluctuating driving current from the
regulator-rectifier;
Figure 3, illustrates output produced by prior art throttle position sensor provided at first
position in the vehicle, when the throttle opening is greater than a predetermined throttle
opening level and when the throttle position sensor receives a fluctuating driving current
from the regulator-rectifier;
Figure 4 illustrates a flow chart of a method for detecting throttle opening level of a throttle
valve provided in a vehicle based on a throttle signal received from at least one throttle
position sensor located at a first position in the vehicle in accordance with an embodiment of
the invention;
Figure 5 illustrates a flow chart of a method for detecting throttle opening level of a throttle
valve provided in a vehicle based on a throttle signal received from at least one throttle
position sensor located at a second position in the vehicle in accordance with another
embodiment of the invention;
Figure 6 illustrates a flow chart of a method for controlling ignition of an internal combustion
engine based on a throttle signal received from at least one throttle position sensor located at
a first position in accordance with an embodiment of the invention;
Figure 7 illustrates a flow chart of a method for controlling ignition of an internal combustion
engine based on a throttle signal received from at least one throttle position sensor located at
a second position in accordance with another embodiment of the invention;
Figure 8 illustrates a block diagram of an apparatus for detecting a throttle opening level by
implementing the method as illustrated in any of figures 4 or 5; and
Figure 9 illustrates a block diagram of an ignition controlling device for controlling ignition
of an internal combustion engine by implementing the method as illustrated in any of figures
6 or 7.
Figure 10 illustrates a flow chart of a method for detecting throttle opening level from two
throttle position sensors located in the vehicle in accordance with another embodiment of the
invention.
Further, skilled artisans will appreciate that elements in the figures are illustrated for
simplicity and may not have been necessarily been drawn to scale. For example, the flow
charts illustrate the method in terms of the most prominent steps involved to help to improve
7
understanding of aspects of the present invention. Furthermore, in terms of the construction
of the device, one or more components of the device may have been represented in the
figures by conventional symbols, and the figures may show only those specific details that
are pertinent to understanding the embodiments of the present invention so as not to obscure
the figures with details that will be readily apparent to those of ordinary skill in the art having
benefit of the description herein.
Detailed Description:
For the purpose of promoting an understanding of the principles of the invention, reference
will now be made to the embodiment illustrated in the figures and specific language will be
used to describe the same. It will nevertheless be understood that no limitation of the scope of
the invention is thereby intended, such alterations and further modifications in the illustrated
system, and such further applications of the principles of the invention as illustrated therein
being contemplated as would normally occur to one skilled in the art to which the invention
relates.
It will be understood by those skilled in the art that the foregoing general description and the
following detailed description are exemplary and explanatory of the invention and are not
intended to be restrictive thereof.
Reference throughout this specification to “an aspect”, “another aspect” or similar language
means that a particular feature, structure, or characteristic described in connection with the
embodiment is included in at least one embodiment of the present invention. Thus,
appearances of the phrase “in an embodiment”, “in another embodiment” and similar
language throughout this specification may, but do not necessarily, all refer to the same
embodiment.
The terms "comprises", "comprising", or any other variations thereof, are intended to cover a
non-exclusive inclusion, such that a process or method that comprises a list of steps does not
include only those steps but may include other steps not expressly listed or inherent to such
process or method. Similarly, one or more devices or sub-systems or elements or structures or
components proceeded by "comprises... a" does not, without more constraints, preclude the
existence of other devices or other sub-systems or other elements or other structures or other
components or additional devices or additional sub-systems or additional elements or
additional structures or additional components.
8
Unless otherwise defined, all technical and scientific terms used herein have the same
meaning as commonly understood by one of ordinary skill in the art to which this invention
belongs. The system, methods, and examples provided herein are illustrative only and not
intended to be limiting.
Embodiments of the present invention will be described below in detail with reference to the
accompanying figures.
Referring to figure 1, there is illustrated a block diagram of an arrangement (100) which is
available in a vehicle. The arrangement includes an alternating current generator (ACG)
(101) producing an alternating current. A regulator / rectifier (102) is connected to the output
of the ACG and is configured to convert the alternating current into a direct current. The
direct current produced by the regulator / rectifier is generally a pulsed direct current having
shape of a square wave. In a battery-less condition, a throttle position sensor (103) (which
may be a magnetic sensor such as a hall-effect sensor) receives the square-wave pulsed direct
current as the driving current. The throttle position sensor (103) produces a throttle signal
indicative of a throttle opening level and the same is provided to a micro-controller (104).
The micro-controller (104) performs the action of determining the throttle opening level from
the throttle signal received from the throttle position sensor (103). The micro-controller (104)
may be additionally configured to control ignition of an internal combustion engine based on
the throttle opening level thus detected. By way of example, the micro-controller (104) may
be configured to control a switching element (105) (more particularly, control a switching
pattern of the switching element). The switching element (105) may in turn, control supply to
an ignition coil, as is well known in the art. The micro-controller (104) may receive a driving
current from the regulator / rectifier after appropriate regulation by a regulating device (106).
Referring to figure 2, there is illustrated output produced by the throttle position sensor of
figure 1, provided at a first position in the vehicle, when the throttle opening is less than a
predetermined throttle opening level and when the throttle position sensor receives the
square-wave pulsed direct current as the driving current from the regulator-rectifier. Figure 2
more particularly shows a pulser coil signal (201), which comprises a first pulse (202), a
second pulse (203), a third pulse (204) and a fourth pulse (205). A time between the first
pulse (202) and the third pulse (204) (or alternatively time between the second pulse (203)
and the fourth pulse (205)) denotes time taken for one rotation of the ACG. Figure 2 also
9
shows output (206) from the regulator-rectifier, i.e. the square-wave pulsed direct current
produced for one rotation of the ACG. When the throttle position sensor receives the squarewave
pulsed direct current from the regulator-rectifier and if the throttle opening is less than
50%, the throttle position sensor produces a fluctuating throttle signal (207), which has
multiple peaks (208).
If the throttle position sensor is provided at a second position in the vehicle, the throttle
position sensor produces the fluctuating throttle signal (207) when the throttle opening is
greater than the predetermined throttle opening level and when the throttle position sensor
receives the square-wave pulsed direct current as the driving current from the regulatorrectifier.
Referring to figure 3, there is illustrated output produced by the throttle position sensor of
figure 1, provided at a first position in the vehicle, when the throttle opening is less than a
predetermined throttle opening level and when the throttle position sensor receives the
square-wave pulsed direct current as the driving current from the regulator-rectifier. Figure 3
more particularly shows a pulser coil signal (201), which comprises a first pulse (202), a
second pulse (203), a third pulse (204) and a fourth pulse (205). A time between the first
pulse (202) and the third pulse (204) (or alternatively time between the second pulse (203)
and the fourth pulse (205)) denotes time taken for one rotation of the ACG. Figure 3also
shows output (206) from the regulator-rectifier, i.e. the square-wave pulsed direct current
produced for one rotation of the ACG. When the throttle position sensor receives the squarewave
pulsed direct current from the regulator-rectifier and if the throttle opening is greater
than 50%, the hall-effect sensor may either produce any one of a constant throttle signal
having a “HIGH” value (301) or a fluctuating throttle signal (302), wherein the fluctuating
throttle signal (302) has multiple peaks (303).
If the throttle position sensor is provided at a second position in the vehicle, the throttle
position sensor produces the fluctuating throttle signal (302) when the throttle opening is less
than the predetermined throttle opening level and when the throttle position sensor receives
the square-wave pulsed direct current as the driving current from the regulator-rectifier.
Although, it is not clear as to the reasons for the throttle position sensor to produce the
fluctuating throttle signal (302), when throttle position sensor receives the square-wave
pulsed direct current as the driving current from the regulator-rectifier and the throttle
10
opening level is greater than a predetermined level; or the fluctuating throttle signal (207),
when the throttle position sensor receives the square-wave pulsed direct current as the driving
current from the regulator-rectifier and the throttle opening level is less than the
predetermined level; it was observed that even if the fluctuating throttle signals are received,
it is possible to accurately detect the throttle opening level.
Accordingly, figure 4 illustrates a flow chart of a method (400) for detecting throttle opening
level of a throttle valve provided in a vehicle based on a throttle signal received from at least
one throttle position sensor located at a first position in the vehicle in accordance with an
embodiment of the invention. The method comprises the step of receiving (401) a throttle
signal from at least one throttle position sensor located at a first position. The method further
comprises the step of determining (402) whether the throttle signal comprises more than one
pulse in one rotation of the alternating current generator and determining (403) whether value
of “R” of the throttle signal is in excess of a predetermined percentage threshold value;
wherein R is defined as:
=

∗ 100.
In case, it is determined that the throttle signal comprises more than one pulse in one rotation
of the alternating current generator and the value of “R” of the throttle signal is in excess of
the predetermined percentage threshold value, the throttle opening level is determined (404)
as being less than a predetermined level.
By way of a non-limiting example, if the throttle signal comprises more than one pulse in one
rotation of the alternating current generator and the value of “R” of the throttle signal is in
excess of 1.5% (the predetermined percentage threshold value), the throttle opening level is
determined as being less than 50% (the predetermined throttle opening level).
In case, it is determined that the throttle signal does not contain more than one pulse in one
rotation of the alternating current generator or in other words, if the throttle signal is at a
continuous predefined level, the throttle opening level is determined (405) as being greater
than the predetermined level.
By way of another non-limiting example, if the throttle signal does not contain more than one
pulse in one rotation of the alternating current generator or in other words, if the throttle
11
signal is at HIGH level, the throttle opening level is determined (405) as being greater than
50% (the predetermined throttle opening level).
In case, it is determined that the throttle signal comprises more than one pulse in one rotation
of the alternating current generator, but the value of “R” of the throttle signal is in less than
the predetermined percentage threshold value, the throttle opening level is determined (405)
as being greater than a predetermined level.
By way of still another non-limiting example, if the throttle signal comprises more than one
pulse in one rotation of the alternating current generator and the value of “R” of the throttle
signal is in less than 1.5% (the predetermined percentage threshold value), the throttle
opening level is determined as being greater than 50% (the predetermined throttle opening
level).
It may be noted that predetermined percentage threshold value may be either more than or
less than 1.5% as mentioned in the examples provided above and depends upon factors such
as (a) the nature of the throttle position sensor; (b) the exact location of the throttle position
sensor; (c) characteristics of the square-wave pulsed direct current produced for one rotation
of the ACG and other factors. It may also be noted that the predetermined throttle opening
level may be either more than or less than 50% as mentioned in the examples provided above
and depends, among other things, upon the predetermined percentage threshold value.
In case the throttle signal is received from at least one throttle position sensor located at a
second position, figure 5 illustrates the flow chart of a method (500) for detecting throttle
opening level of the throttle valve in accordance with another embodiment of the invention.
The method comprises the step of receiving (501) a throttle signal from at least one throttle
position sensor located at the second position. The method further comprises the step of
determining (502) whether the throttle signal comprises more than one pulse in one rotation
of the alternating current generator and determining (503) whether value of “R” of the throttle
signal is in excess of a predetermined percentage threshold value; wherein R is defined as:
=

∗ 100.
In case, it is determined that the throttle signal comprises more than one pulse in one rotation
of the alternating current generator and the value of “R” of the throttle signal is in excess of
12
the predetermined percentage threshold value, the throttle opening level is determined (504)
as being greater than a predetermined level.
By way of a non-limiting example, if the throttle signal comprises more than one pulse in one
rotation of the alternating current generator and the value of “R” of the throttle signal is in
excess of 1.5% (the predetermined percentage threshold value), the throttle opening level is
determined as being greater than 50% (the predetermined throttle opening level).
In case, it is determined that the throttle signal does not contain more than one pulse in one
rotation of the alternating current generator or in other words, if the throttle signal is at a
continuous predefined level (a HIGH level), the throttle opening level is determined (505) as
being less than the predetermined level.
By way of another non-limiting example, if the throttle signal does not contain more than one
pulse in one rotation of the alternating current generator or in other words, if the throttle
signal is at HIGH level, the throttle opening level is determined (505) as being less than 50%
(the predetermined throttle opening level).
In case, it is determined that the throttle signal comprises more than one pulse in one rotation
of the alternating current generator and the value of “R” of the throttle signal is in less than
the predetermined percentage threshold value, the throttle opening level is determined (505)
as being less than a predetermined level.
By way of yet another non-limiting example, if the throttle signal comprises more than one
pulse in one rotation of the alternating current generator and the value of “R” of the throttle
signal is in less than 1.5% (the predetermined percentage threshold value), the throttle
opening level is determined as being less than 50% (the predetermined throttle opening
level).
As one of the reasons for detecting a throttle opening level of a throttle valve provided in a
vehicle, is to control ignition of an internal combustion engine provided in the vehicle, the
invention also provides method for controlling ignition of the internal combustion engine.
Now referring to figure 6, there is illustrated a flow chart of a method (600) for controlling
ignition of an internal combustion engine based on a throttle signal received from at least one
throttle position sensor located at a first position in accordance with an embodiment of the
13
invention. The method (600) is based on the method (400) as illustrated in figure 4 and
explained above. Thus, the method (600) for controlling ignition of an internal combustion
engine comprises all the steps of method (400) for detecting throttle opening level and such
common steps are being referred to by same reference numerals in figure 6. However, for the
sake of completeness, the method (600) for controlling ignition of an internal combustion
engine is described in total below.
The method (600) for controlling ignition of an internal combustion engine comprises
receiving (401) a throttle signal from at least one throttle position sensor located at a first
position. The method further comprises the step of determining (402) whether the throttle
signal comprises more than one pulse in one rotation of the alternating current generator and
determining (403) whether value of “R” of the throttle signal is in excess of a predetermined
percentage threshold value; wherein R is defined as:
=

∗ 100.
In case, it is determined that the throttle signal comprises more than one pulse in one rotation
of the alternating current generator and the value of “R” of the throttle signal is in excess of
the predetermined percentage threshold value, the throttle opening level is determined (404)
as being less than a predetermined level.
By way of a non-limiting example, if the throttle signal comprises more than one pulse in one
rotation of the alternating current generator and the value of “R” of the throttle signal is in
excess of 1.5% (the predetermined percentage threshold value), the throttle opening level is
determined as being less than 50% (the predetermined throttle opening level).
Once it is determined that the throttle opening level is less than a predetermined level, the
method (600) comprises providing (601) a first control signal for controlling an ignition
timing on basis of a first characteristic, the first characteristics corresponding to throttle
opening level being less than a predetermined value.
In case, it is determined that the throttle signal does not contain more than one pulse in one
rotation of the alternating current generator or in other words, if the throttle signal is at a
continuous predefined level, the throttle opening level is determined (405) as being greater
than the predetermined level.
14
By way of another non-limiting example, if the throttle signal does not contain more than one
pulse in one rotation of the alternating current generator or in other words, if the throttle
signal is at HIGH level, the throttle opening level is determined (405) as being greater than
50% (the predetermined throttle opening level).
In case, it is determined that the throttle signal comprises more than one pulse in one rotation
of the alternating current generator, but the value of “R” of the throttle signal is in less than
the predetermined percentage threshold value, the throttle opening level is determined (405)
as being greater than a predetermined level.
By way of still another non-limiting example, if the throttle signal comprises more than one
pulse in one rotation of the alternating current generator and the value of “R” of the throttle
signal is in less than 1.5% (the predetermined percentage threshold value), the throttle
opening level is determined as being greater than 50% (the predetermined throttle opening
level).
If it is however determined that the throttle opening level is greater than the predetermined
level, the method (600) comprises providing (602) a second control signal for controlling an
ignition timing on basis of a second characteristic, the second characteristics corresponding to
throttle opening level being greater than the predetermined value.
Now referring to figure 7, there is illustrated a flow chart of a method (700) for controlling
ignition of an internal combustion engine based on a throttle signal received from at least one
throttle position sensor located at a second position in accordance with an embodiment of the
invention. The method (700) is based on the method (500) as illustrated in figure 5 and
explained above. Thus, the method (700) for controlling ignition of an internal combustion
engine comprises all the steps of method (500) for detecting throttle opening level and such
common steps are being referred to by same reference numerals in figure 7 and are not being
explained again for the sake of brevity.
In case, the throttle opening level is determined (504) as being greater than a predetermined
level, the method (700) further comprises providing (701) a second control signal for
controlling an ignition timing on basis of a second characteristic, the second characteristics
corresponding to throttle opening level being greater than a predetermined value.
15
If however, it is determined that the throttle opening less than the predetermined level, the
method (700) comprises providing (702) a first control signal for controlling an ignition
timing on basis of a first characteristic, the first characteristics corresponding to throttle
opening level less than the predetermined value.
Now referring to figure 8, there is illustrated a block diagram of an apparatus (800) for
detecting a throttle opening level. The apparatus (800) comprises a receiving unit (801) for
receiving a throttle signal from at least one throttle position sensor; and a determining unit
(802) for determining the throttle opening level. The apparatus (800) can be configured to
implement either the method as illustrated in figure 4 or alternatively the method as
illustrated in figure 5.
In case the apparatus (800) is configured to implement the method as illustrated in figure 4,
then the receiving unit (801) is adapted to receive a throttle signal from at least one throttle
position sensor located at a first position and the determining unit (802) is adapted to
determine the throttle opening level as being less than a predetermined level if:
(a) the throttle signal comprises more than one pulse in one rotation of the alternating
current generator; and
(b) value of “R” of the throttle signal is in excess of the predetermined percentage
threshold value, wherein R is defined as:
=

∗ 100.
In this embodiment, the determining unit (802) is further adapted to determine the throttle
opening level as being greater than the predetermined level if:
(i) the throttle signal does not contain more than one pulse in one rotation of the
alternating current generator or in other words, if the throttle signal is at a continuous
predefined level; OR
(ii) the throttle signal comprises more than one pulse in one rotation of the alternating
current generator, and the value of “R” of the throttle signal is in less than the predetermined
percentage threshold value.
In case the apparatus (800) is configured to implement the method as illustrated in figure 5,
then the receiving unit (801) is adapted to receive a throttle signal from at least one throttle
16
position sensor located at a second position and the determining unit (802) is adapted to
determine the throttle opening level as being greater than a predetermined level if:
(c) the throttle signal comprises more than one pulse in one rotation of the alternating
current generator; and
(d) value of “R” of the throttle signal is in excess of the predetermined percentage
threshold value, wherein R is defined as:
=

∗ 100.
In this embodiment, the determining unit (802) is further adapted to determine the throttle
opening level as being less than the predetermined level if:
(i) the throttle signal does not contain more than one pulse in one rotation of the
alternating current generator or in other words, if the throttle signal is at a continuous
predefined level; OR
(ii) the throttle signal comprises more than one pulse in one rotation of the alternating
current generator, and the value of “R” of the throttle signal is in less than the predetermined
percentage threshold value.
In a further embodiment of the invention, the apparatus (800) may be further provided with a
means (803) to determine TON (the time duration corresponding to a HIGH state of the pulse
contained in throttle signal), TOFF (the time duration for which pulse contained in throttle
signal is in LOW state) and the value of “R”.
In a furthermore embodiment of the invention, the apparatus (800) may be further provided
with a storage element (804) for storing the predetermined percentage threshold value and the
predetermined throttle opening level.
Now referring to figure 9, there is illustrated a block diagram of an ignition control device
(900) for controlling ignition of an internal combustion engine in accordance with the
teachings of the invention. The apparatus (900) comprises a receiving unit (801) for receiving
a throttle signal from at least one throttle position sensor; and a signal generating unit (902)
for generating a control signal for controlling ignition of an internal combustion engine. The
ignition control device (900) can be configured to implement either the method as illustrated
in figure 6 or alternatively the method as illustrated in figure 7.
17
In case the apparatus (900) is configured to implement the method as illustrated in figure 6,
then the receiving unit (901) is adapted to receive a throttle signal from at least one throttle
position sensor located at a first position and the signal generating unit (902) is adapted to
provide a first control signal for controlling an ignition timing on basis of a first
characteristic, the first characteristics corresponding to throttle opening level being less than a
predetermined value. The signal generating unit (902) produces the first control signal if the
throttle opening level is determined to be less than the predetermined value. A determining
unit (802) as illustrated in figure 8 above that determines the throttle opening level as being
less than a predetermined level if:
(e) the throttle signal comprises more than one pulse in one rotation of the alternating
current generator; and
(f) value of “R” of the throttle signal is in excess of the predetermined percentage
threshold value, wherein R is defined as:
=

+

∗ 100
may be operably linked to the signal generating unit (902).
In this embodiment, the signal generating unit (902) produces the second control signal if the
throttle opening level is determined to be greater than the predetermined value.
In case the apparatus (900) is configured to implement the method as illustrated in figure 7,
then the receiving unit (901) is adapted to receive a throttle signal from at least one throttle
position sensor located at a second position and the signal generating unit (902) is adapted to
provide a second control signal for controlling an ignition timing on basis of a second
characteristic, the second characteristics corresponding to throttle opening level being greater
than a predetermined value. The signal generating unit (902) produces the second control
signal if the throttle opening level is determined to be greater than the predetermined value. A
determining unit (802) as illustrated in figure 8 above can be used for determining the throttle
opening level, wherein the determining unit determines the throttle opening level as being
greater than a predetermined level if:
(g) the throttle signal comprises more than one pulse in one rotation of the alternating
current generator; and
(h) value of “R” of the throttle signal is in excess of the predetermined percentage
threshold value, wherein R is defined as:
18
=

+

∗ 100
may be operably linked to the signal generating unit (902).
In this embodiment, the signal generating unit (902) produces a first control signal if the
throttle opening level is determined to be less than the predetermined value.
In a further embodiment of the invention, the apparatus (900) may be further provided with a
means (803) to determine TON (the time duration corresponding to a HIGH state of the pulse
contained in throttle signal), TOFF (the time duration for which pulse contained in throttle
signal is in LOW state) and the value of “R”.
In a furthermore embodiment of the invention, the apparatus (900) may be further provided
with a storage element (804) for storing the predetermined percentage threshold value and the
predetermined throttle opening level.
While in the above paragraphs, the throttle opening level based on throttle signal received
from one throttle position sensor (located either at a first position or a second position has
been described), the method can be extended to detect throttle opening level based on two or
more throttle signals received from multiple throttle position sensors.
Now referring to figure 10, there is illustrated a flow chart of a method (1000) for detecting
throttle opening level of a throttle valve provided in a vehicle based on two throttle signals
received from two throttle position sensors provided in the vehicle in accordance with an
embodiment of the invention. The method comprises the step of receiving (1001) a first
throttle signal from a first throttle position sensor and a second throttle signal from a second
throttle position sensor.
The method further comprises the step of determining (1002) whether the first throttle signal
comprises more than one pulse in one rotation of the alternating current generator and
determining (1003) whether value of “R1” of the first throttle signal is in excess of a
predetermined first percentage threshold value; wherein R1 is defined as:
1 =

∗ 100.
In case, it is determined that the first throttle signal comprises more than one pulse in one
rotation of the alternating current generator and the value of “R1” of the first throttle signal is
19
in excess of the predetermined first percentage threshold value, the throttle opening level is
determined (1004) as being less than a first predetermined level.
In case, it is determined that the first throttle signal comprises more than one pulse in one
rotation of the alternating current generator, but the value of “R1” of the first throttle signal is
less than the predetermined first percentage threshold value, the method proceeds to
determining (1005) whether the second throttle signal comprises more than one pulse in one
rotation of the alternating current generator; and determining (1006) whether value of “R2”
of the second throttle signal is in excess of a predetermined second percentage threshold
value; wherein R2 is defined as:
2 =

∗ 100.
In case, it is determined that:
(a) the first throttle signal comprises more than one pulse in one rotation of the
alternating current generator (1002);
(b) the value of “R1” of the first throttle signal is less than the predetermined first
percentage threshold value (1003);
(c) the second throttle signal comprises more than one pulse in one rotation of the
alternating current generator (1005); and
(d) the value of “R2” of the second throttle signal is greater than the predetermined
second percentage threshold value (1006);
the throttle opening level is determined (1007) as being greater than the first predetermined
level but less than a second predetermined level.
In case, it is determined that:
(a) the first throttle signal comprises more than one pulse in one rotation of the
alternating current generator (1002);
(b) the value of “R1” of the first throttle signal is less than the predetermined first
percentage threshold value (1003); and
(c) the second throttle signal does NOT comprises more than one pulse in one rotation of
the alternating current generator (1005) or in other words the second throttle signal is
at a continuous predefined level;
the throttle opening level is determined (1008) as being greater than the second
predetermined level.
20
In case, it is determined that:
(a) the first throttle signal comprises more than one pulse in one rotation of the
alternating current generator (1002);
(b) the value of “R1” of the first throttle signal is less than the predetermined first
percentage threshold value (1003);
(c) the second throttle signal comprises more than one pulse in one rotation of the
alternating current generator (1005); and
(d) the value of “R2” of the second throttle signal is less than the predetermined second
percentage threshold value (1006);
the throttle opening level is determined (1008) as being greater than the second
predetermined level.
In case, it is determined that the first throttle signal comprises does NOT comprises more
than one pulse in one rotation of the alternating current generator (1002) or in other words the
first throttle signal is at a continuous predefined level, the method proceeds to check whether
the second throttle signal comprises more than one pulse in one rotation of the alternating
current generator (1005). If the second throttle signal does NOT comprises more than one
pulse in one rotation of the alternating current generator or in other words the second throttle
signal is at a continuous predefined level, the throttle opening level is determined (1008) as
being greater than the second predetermined level.
In case it is determined that the first throttle signal comprises does NOT comprises more than
one pulse in one rotation of the alternating current generator (1002) or in other words the first
throttle signal is at a continuous predefined level; and the second throttle signal comprises
more than one pulse in one rotation of the alternating current generator (1005), the method
proceeds to determining (1006) whether value of “R2” of the second throttle signal is in
excess of the predetermined second percentage threshold value; wherein R2 is defined as:
2 =

∗ 100.
If the value of “R2” of the second throttle signal is greater than the predetermined second
percentage threshold value (1006), the throttle opening level is determined (1008) as being
greater than the first predetermined level and less than the second predetermined level.
21
If however, the value of R2 is less than the predetermined second percentage threshold value
(1006), the throttle opening level is determined (1008) as being greater than the second
predetermined level.
By way of a non-limiting example, the predetermined first percentage threshold value can be
set as 1.5%.
By way of another non-limiting example, the predetermined second percentage threshold
value can be set as 1.5%.
By way of yet another non-limiting example, the first predetermined throttle opening level
can be set as 33%.
By way of still another non-limiting example, the second predetermined throttle opening
level can be set as 66%.
By way of a further non-limiting example, the continuous predefined level corresponding to
the first throttle signal is a HIGH level.
By way of a further more non-limiting example, the continuous predefined level
corresponding to the second throttle signal is a HIGH level.
The table provided below summarizes the outcome of the figure 10.
Characteristics of First
Throttle Signal
Characteristics of Second
Throttle Signal
Throttle Opening level
Contains more than 1 pulse,
and value of R1 is greater
than 1.5%
Any type of characteristics Less than 33%
Contains more than 1 pulse,
and value of R1 is less than
1.5%
Contains more than 1 pulse,
and value of R2 is greater
than 1.5%
Greater than 33% and less
than 66%
Contains more than 1 pulse,
and value of R1 is less than
1.5%
Contains more than 1 pulse,
and value of R2 is less than
1.5%
Greater than 66%
Contains than 1 pulse, and Is at continuous HIGH level Greater than 66%
22
value of R1 is less than
1.5%
Is at continuous HIGH level Is at continuous HIGH level Greater than 66%
Is at continuous HIGH level Contains more than 1 pulse,
and value of R2 is greater
than 1.5%
Greater than 33% and less
than 66%
Is at continuous HIGH level Contains more than 1 pulse,
and value of R2 is less than
1.5%
Greater than 66%
From the above, it can be observed that the method of the present invention is not only
applicable for determining the throttle opening level from a single throttle signal, but also
from multiple throttle signals. Although in figure 10, the method has been illustrated using
two throttle signals, the method can be further extended to include more than two throttle
signals, in which case the opening level can be more accurately determined. By way of
example, if there are 3 throttle position sensors are located at equal distance between 0% and
100% opening level, the throttle opening level can be determined as being (a) less than 25%;
(b) between 25% and 50%; (c) between 50% and 75%; and (d) between 75% and 100%.
It may be noted that in the specification, it has been stated that the throttle position sensor can
be either located at a first position or at a second position. If we consider a magnetic effect
based throttle position sensor, it can be understood that a combination of a magnet and a halleffect
chip together function as the throttle position sensor. Thus, in one embodiment,
location of the throttle position sensor at the first position or location of the throttle position
sensor at the second location can be understood to mean location of the magnet at the first
location or location of the magnet at the second location (with the location of the hall-effect
chip being same). However, it may be noted that the reverse is also feasible i.e. in another
embodiment, location of the throttle position sensor at the first position or location of the
throttle position sensor at the second location can be understood to mean location of the halleffect
chip at the first location or location of the hall-effect chip at the second location (with
the location of the magnet being same).
While specific language has been used to describe the disclosure, any limitations arising on
account of the same are not intended. As would be apparent to a person in the art, various
23
working modifications may be made to the method in order to implement the inventive
concept as taught herein.
The figures and the forgoing description give examples of embodiments. Those skilled in the
art will appreciate that one or more of the described elements may well be combined into a
single functional element. Alternatively, certain elements may be split into multiple
functional elements. Elements from one embodiment may be added to another embodiment.
For example, orders of processes described herein may be changed and are not limited to the
manner described herein. Moreover, the actions of any flow diagram need not be
implemented in the order shown; nor do all of the acts necessarily need to be performed.
Also, those acts that are not dependent on other acts may be performed in parallel with the
other acts. The scope of embodiments is by no means limited by these specific examples.
Numerous variations, whether explicitly given in the specification or not, such as differences
in structure, dimension, and use of material, are possible. The scope of embodiments is at
least as broad as given by the following claims.

WE CLAIM:
1. A method for detecting a throttle opening level of a throttle valve provided in a
vehicle, said method comprises the steps of:
a. receiving a throttle signal from at least one throttle position sensor located at a
first position, and
b. determining the throttle opening level as being less than a predetermined value
if:
i. the throttle signal comprises more than one pulse in one rotation of an
alternating current generator; and
ii. value of “R” of the throttle signal is in excess of a predetermined
threshold value; R being defined as:
=

∗ 100;
wherein TON is a time duration corresponding to a HIGH state of the
pulse contained in throttle signal and TOFF is a time duration for which
pulse contained in throttle signal is in LOW state.
2. The method as claimed in claim 1, further comprises determining the throttle opening
level as being greater than the predetermined level if the throttle signal is at a
continuous predefined level in one rotation of the alternating current generator.
3. The method as claimed in claim 1, further comprises determining the throttle opening
level as being greater than the predetermined level if (a) the throttle signal comprises
more than one pulse in one rotation of the alternating current generator; and (b) the
value of “R” of the throttle signal is less than the predetermined threshold value.
4. The method as claimed in claim 1, wherein the predetermined percentage threshold
value of R is about 1.5% and the predetermined throttle opening level is about 50%.
5. A method for controlling ignition of an internal combustion engine, said method
comprises the steps of:
a. receiving a throttle signal from at least one throttle position sensor located at a
first location; and
b. providing a first control signal for controlling an ignition timing on basis of a
first characteristic, the first characteristics corresponding to throttle opening
25
level being less than a predetermined value, wherein the throttle opening level
is determined to be less than the predetermined value if:
i. the throttle signal comprises more than one pulse in one rotation of an
alternating current generator and
ii. value of “R” of the throttle signal is in excess of a predetermined
threshold value; R being defined as:
=

∗ 100
wherein TON is a time duration corresponding to a HIGH state of the
pulse contained in throttle signal and TOFF is a time duration for which
pulse contained in throttle signal is in LOW state.
6. The method as claimed in claim 5, further comprises providing a second control
signal for controlling an ignition timing on basis of a second characteristic, the second
characteristics corresponding to throttle opening level being greater than the
predetermined value, wherein the throttle opening level is determined to be greater
than the predetermined value if the throttle signal is at a continuous predefined level
in one rotation of the alternating current generator.
7. The method as claimed in claim 5, further comprises providing a second control
signal for controlling an ignition timing on basis of a second characteristic, the second
characteristics corresponding to throttle opening level being greater than the
predetermined value, wherein the throttle opening level is determined to be greater
than the predetermined value if (a) the throttle signal comprises more than one pulse
in one rotation of an alternating current generator and (b) the value of “R” of the
throttle signal is less than the predetermined threshold value.
8. An apparatus for detecting a throttle position level of a throttle valve provided in a
vehicle, said apparatus comprises:
a receiving unit for receiving a throttle signal from at least one throttle position sensor
located at a first position; and
a determining unit for determining the throttle opening level as being less than a
predetermined value if:
(a) the throttle signal comprises more than one pulse in one rotation of an alternating
current generator; and
26
(b)value of “R” of the throttle signal is in excess of a predetermined threshold value;
R being defined as:
=

∗ 100
wherein TON is a time duration corresponding to a HIGH state of the pulse contained
in throttle signal and TOFF is a time duration for which pulse contained in throttle
signal is in LOW state.
9. The apparatus as claimed in claim 8, further comprising a means to determine value
of TON, value of TOFF and the value of “R”.
10. The apparatus as claimed in claim 8, further comprising a storage element for storing
the predetermined percentage threshold value and the predetermined throttle opening
level.
11. An ignition control device for controlling ignition of an internal combustion engine,
said ignition control device comprises:
a receiving unit adapted to receive a throttle signal from at least one throttle position
sensor located at a first position; and
signal generating unit for providing a first control signal for controlling an ignition
timing on basis of a first characteristic, the first characteristics corresponding to
throttle opening level being less than a predetermined value, wherein the throttle
opening level is determined, by the processing unit, to be less than the predetermined
value if:
(a) the throttle signal comprises more than one peak in one rotation of an alternating
current generator; and
(b) value of “R” of the throttle signal is in excess of a predetermined threshold value;
R being defined as:
=

∗ 100
wherein TON is a time duration corresponding to a HIGH state of the pulse contained
in throttle signal and TOFF is a time duration for which pulse contained in throttle
signal is in LOW state.
12. The apparatus as claimed in claim 11, further comprising a means to determine value
of TON, value of TOFF and the value of “R”.
27
13. The apparatus as claimed in claim 11, further comprising a storage element for storing
the predetermined percentage threshold value and the predetermined throttle opening
level.
14. A method for detecting a throttle opening level of a throttle valve provided in a
vehicle, said method comprises the steps of:
a. receiving a throttle signal from at least one throttle position sensor located at a
second position, and
b. determining the throttle opening level as being greater than a predetermined
value if:
i. the throttle signal comprises more than one pulse in one rotation of an
alternating current generator; and
ii. value of “R” of the throttle signal is in excess of a predetermined
threshold value; R being defined as:
=

∗ 100
wherein TON is a time duration corresponding to a HIGH state of the
pulse contained in throttle signal and TOFF is a time duration for which
pulse contained in throttle signal is in LOW state.
15. The method as claimed in claim 14, further comprises determining the throttle
opening level as being less than the predetermined level if the throttle signal is at a
continuous predefined level in one rotation of the alternating current generator.
16. The method as claimed in claim 14, further comprises determining the throttle
opening level as being less than the predetermined level if (a) the throttle signal
comprises more than one pulse in one rotation of the alternating current generator;
and (b) the value of “R” of the throttle signal is less than the predetermined threshold
value.
17. The method as claimed in claim 14, wherein the predetermined percentage threshold
value of R is about 1.5% and the predetermined throttle opening level is about 50%.
18. A method for controlling ignition of an internal combustion engine, said method
comprises the steps of:
a. receiving a throttle signal from at least one throttle position sensor located at a
second location; and
28
b. providing a second control signal for controlling an ignition timing on basis of
a second characteristic, the second characteristics corresponding to throttle
opening level being greater than a predetermined value, wherein the throttle
opening level is determined to be greater than the predetermined value if:
i. the throttle signal comprises more than one pulse in one rotation of an
alternating current generator and
ii. value of “R” of the throttle signal is in excess of a predetermined
threshold value; R being defined as:
=

∗ 100.
wherein TON is a time duration corresponding to a HIGH state of the
pulse contained in throttle signal and TOFF is a time duration for which
pulse contained in throttle signal is in LOW state.
19. The method as claimed in claim 18, further comprises providing a first control signal
for controlling an ignition timing on basis of a first characteristic, the first
characteristics corresponding to throttle opening level being less than the
predetermined value, wherein the throttle opening level is determined to be less than
the predetermined value if the throttle signal is at a continuous predefined level in one
rotation of the alternating current generator.
20. The method as claimed in claim 18, further comprises providing a first control signal
for controlling an ignition timing on basis of a first characteristic, the first
characteristics corresponding to throttle opening level being less than the
predetermined value, wherein the throttle opening level is determined to be less than
the predetermined value if (a) the throttle signal comprises more than one pulse in one
rotation of an alternating current generator and (b) the value of “R” of the throttle
signal is less than the predetermined threshold value.
21. An apparatus for detecting a throttle position level of a throttle valve provided in a
vehicle, said apparatus comprises:
a receiving unit for receiving a throttle signal from at least one throttle position sensor
located at a second location; and
a determining unit for determining the throttle opening level as being less than a
predetermined value if:
29
(a) the throttle signal comprises more than one pulse in one rotation of an alternating
current generator; and
(b) value of “R” of the throttle signal is in excess of a predetermined threshold value;
R being defined as:
=

∗ 100.
wherein TON is a time duration corresponding to a HIGH state of the pulse contained
in throttle signal and TOFF is a time duration for which pulse contained in throttle
signal is in LOW state.
22. An ignition control device for controlling ignition of an internal combustion engine,
said ignition control device comprises:
a receiving unit adapted to receive a throttle signal from at least one throttle position
sensor located at a second location; and
processing unit for providing a second control signal for controlling an ignition timing
on basis of a second characteristic, the second characteristics corresponding to throttle
opening level being greater than a predetermined value, wherein the throttle opening
level is determined, by the processing unit, to be greater than the predetermined value
if:
(a) the throttle signal comprises more than one peak in one rotation of an alternating
current generator; and
(b) value of “R” of the throttle signal is in excess of a predetermined threshold value;
R being defined as:
=

∗ 100`.
wherein TON is a time duration corresponding to a HIGH state of the pulse contained
in throttle signal and TOFF is a time duration for which pulse contained in throttle
signal is in LOW state.