FIELD OF INVENTION:
[001] The present subject matter described herein, relates to a gear detection
system for a vehicle and, in particularly, to gear detection system for manual
transmission to detect current gear in the vehicle.
BACKGROUND AND PRIOR ART:
[002] In the automotive field, it is often required to capture the gear shift
information like number of gear shifts and gear shift pattern in various driving
conditions. A straightforward method is to observe the number of gearshifts and
10 noting them down. But this way is very tedious, prone to human errors and
requires additional person apart from driver to note the gearshifts.
[003] Conventionally some system exist which uses magnetic field sensor at
gear shift lever to detect position of the gear shift lever and based on the position
of the gear shift lever current gear is detected. This system requires a plurality of
15 components and a complex method to determine the current gear. This system is
costly also.
[004] Therefore, there is a need in the art to provide a gear detect system that
requires less number of part and simple in processing. The present subject matter
provides a technical solution for the same.
20 OBJECTS OF THE INVENTION:
[005] The principal object of the present invention is to provide a gear detection
system for detecting current gear in manual transmission of vehicle.
[006] Another object of the present subject matter is to provide a gear detection
system that is based on magnetic field sensor and determine position of current
25 gear based on the signals provided by the magnetic field sensor.
[007] Another object of the present subject matter is to provide a cylindrical
hollow sleeve with predefined cutouts that corresponds relatively with at least
three magnetic field sensor to provide its output based on solid surface and cutout.
3
[008] Another object of the present subject matter is to provide a predefined
micro-controller with pre-stored gear positioned data with reference to sensor
output signal based on the cylindrical sleeve position with gear shift shaft.
[009] Another object of the present subject matter is to provide a gear detection
system that is cost efficient, effective, reliable and robust in detection of 5 current
gear position in the manual transmission of the vehicle.
[0010] These and other objects and advantages of the present subject matter will
be apparent to a person skilled in the art after consideration of the following
detailed description taken into consideration with accompanying drawings in
10 which preferred embodiments of the present subject matter are illustrated.
SUMMARY OF THE INVENTION:
[0011] One or more drawbacks of conventional gear detection system for manual
transmission are overcome, and additional advantages are provided through the
present gear detection system as claimed in the present disclosure. Additional
15 features and advantages are realized through the technicalities of the present
disclosure. Other embodiments and aspects of the disclosure are described in
detail herein and are considered to be a part of the claimed disclosure.
[0012] The present subject matter relates to a gear detection system for manual
transmission to detect gear position in vehicle. The gear detection system includes
20 a gear shift tower having a gear shift shaft and a gear shift guide case. The gear
shift shaft has a cylindrical hollow sleeve that is mounted under the gear shift
guide case. The gear shift guide case covers the cylindrical hollow sleeve
completely. Further, at least three magnetic field sensors are positioned on the
gear shift guide case relatively with the cylindrical hollow sleeve to generate
25 magnetic field signals based on the presence and absence of the cylindrical hollow
sleeve. The gear detection system is coupled with a micro-controller that is
configured to receive generated magnetic signals and determine current gear by
comparing the received magnetic signals with the pre-stored signals or output.
4
[0013] In an embodiment of the present subject matter, the micro-controller
determine position of the cylindrical hollow sleeve with respect to the at least
three magnetic field sensors and generate an output signal that indicates the
current gear. The three magnetic field sensors generate six different output signal
corresponding to six different cylindrical hollow sleeve positions for detection o5 f
six gear positions. The microcontroller matches the position of the cylindrical
hollow sleeve with predefined cylindrical hollow sleeve positions and determine
the current gear position.
[0014] In another embodiment of the present subject matter, the cylindrical
10 hollow sleeve consists two vertical cutouts along axis (Y) and one square cutout
in between the two vertical cutouts on the cylindrical surface. The two vertical
cutouts and the square cutout of the cylindrical hollow sleeve are relatively
positioned in front of the at least three magnetic field sensors. The three magnetic
field sensors generates a pattern based on position of the two vertical cutouts and
15 the square cutout of the cylindrical hollow sleeve.
[0015] It is preferable that the magnetic field sensors are positioned triangularly
on the gear shift guide case.
[0016] It is preferable that the micro-controller is Electronic Control Unit (ECU)
of the vehicle.
20 [0017] To further understand the characteristics and technical contents of the
present subject matter, a description relating thereto will be made with reference
to the accompanying drawings. However, the drawings are illustrative only but
not used to limit scope of the present subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
25 [0018] It is to be noted, however, that the appended drawings illustrate only
typical embodiments of the present subject matter and are therefore not to be
considered for limiting of its scope, for the invention may admit to other equally
effective embodiments. The detailed description is described with reference to the
accompanying figures. In the figures, the left-most digit(s) of a reference number
5
identifies the figure in which the reference number first appears. The same
numbers are used throughout the figures to reference like features and
components. Some embodiments of system or methods in accordance with
embodiments of the present subject matter are now described, by way of example,
and with reference to the accompanying figures, 5 , in which:
[0019] Fig. 1 illustrates structure of cylindrical hollow sleeve, in accordance with
an embodiment of the present subject matter;
[0020] Fig. 2 illustrates gear detection system of manual transmission, in
accordance with an embodiment of the present subject matter; and
10 [0021] Fig. 3 illustrates positions of cylindrical hollow sleeve and at least three
sensors, in accordance with embodiment of the present subject;
[0022] Fig. 4 illustrates an example of gear select and shift pattern in manual
transmission, in accordance with embodiment of the present subject; and
[0023] Fig. 5a-5g illustrate position of the at least three sensors with the
15 cylindrical hollow sleeve for different gear detection in manual transmission, in
accordance with embodiment of the present subject.
[0024] The figures depict embodiments of the present subject matter for the
purposes of illustration only. A person skilled in the art will easily recognize from
the following description that alternative embodiments of the structures and
20 methods illustrated herein may be employed without departing from the principles
of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0025] It should be noted that the description and figures merely illustrate the
principles of the present subject matter. It should be appreciated by those skilled
25 in the art that conception and specific embodiment disclosed may be readily
utilized as a basis for modifying or designing other structures for carrying out the
same purposes of the present subject matter. It should also be appreciated by those
skilled in the art that by devising various arrangements that, although not
explicitly described or shown herein, embody the principles of the present subject
6
matter and are included within its scope. Furthermore, all examples recited herein
are principally intended expressly to be for pedagogical purposes to aid the reader
in understanding the principles of the present subject matter and the concepts
contributed by the inventor(s) to furthering the art and are to be construed as being
without limitation to such specifically recited examples and conditions. The 5 novel
features which are believed to be characteristic of the present subject matter, both
as to its organization and method of operation, together with further objects and
advantages will be better understood from the following description when
considered in connection with the accompanying figures.
10 [0026] These and other advantages of the present subject matter would be
described in greater detail with reference to the following figures. It should be
noted that the description merely illustrates the principles of the present subject
matter. It will thus be appreciated that those skilled in the art will be able to devise
various arrangements that, although not explicitly described herein, embody the
15 principles of the present subject matter and are included within its scope.
[0027] As shown in the figure 1, the structure of the cylindrical sleeve is explained.
Hereinafter, the arrows X and Y shown in the diagrams respectively indicate the
horizontal direction and vertical direction respectively.
[0028] FIG. 1 illustrates structure of the cylindrical hollow sleeve, in accordance
20 with an embodiment of the present subject matter. The cylindrical hollow sleeve 100
is a ferro-magnetic metal. The cylindrical hollow sleeve 100 has one end 100a and
other end 100b. On either of the end, the cylindrical hollow sleeve 100 has a
provision for mounting with a gear shift shaft. In the present example, the provision
102a is provided on the other end 100b that has smaller diameter ‘d’ than the one end
25 100a. The other end 100b has an extend portion 102 that coupled with the gear shift
shaft of the gear shift tower via a pin or screw.
[0029] As shown in the figure 1, the cylindrical hollow sleeve 100 has two vertical
cutouts 101a, 101b along axis (Y) and one rectangular cutout 101c in between the two
vertical cutouts 101a, 101b. The vertical cutout 101a has one cutout 101d
30 continuously in direction axis X. The cutout 101d has same dimensions as rectangular
7
cutout 101c. The purpose and use of cutouts in the cylindrical hollow sleeve 100 is
explained in the figure 2 and 3.
[0030] Referring to figure 2, a gear detection system 200 is described. The gear
detection system 200 for manual transmission includes a gear shift tower having a
gear shift shaft 201 and a gear shift guide case 202. The gear shift shaft 201 an5 d
the gear shift guide case 202 is well known to a person skilled in the art and well
known in the arts. Therefore, to avoid ambiguity, the detailed structure and
working of the gear shift shaft and the gear shift guide is avoided. The gear shift
shaft 201 connected with gear shift lever to receive selection and shift inputs. The
10 gear shift shaft 201 provided in the transmission box via the gear shift guide case
202. The gear shift guide case 202 is fixed with the transmission box through
bolts and screws or any other known mechanism. The gear shift shaft 201 moves
up-down and rotates in the gear shift guide for selection and shifting the gears
respectively.
15 [0031] The cylindrical hollow sleeve 203 (100) is mounted on the gear shift shaft
201 via mounting provision 102a through pin or screw. The cylindrical hollow
sleeve 203 undergoes a combination of rotary and linear motion during a gear
shift and selection respectively. The cylindrical hollow sleeve 203 is housed
inside the gear shift guide case 202.
20 [0032] Referring to figure 3, at least three magnetic field sensors 204 (hall type
sensors) is positioned on the gear shift guide case 202. The at least three magnetic
field sensors 204 detect the presence or absence of Ferro-magnetic metals in front
of its sensing area by giving a low and a high output signals respectively. The at
least three magnetic field sensors 204 are positioned relatively with the cylindrical
25 hollow sleeve 203 to detect presence and absence of the cylindrical sleeve 203.
Based on the presence and absence, the magnetic field sensors generate magnetic
field signals.
[0033] Further, a micro-controller is coupled with the at least three magnetic field
sensor to receive generated magnetic signals. The micro-controller determines
30 position of the cylindrical hollow sleeve 203 with respect to the at least three
8
magnetic field sensors and generate an output signal that indicates the current gear
by comparing the generated signal with pre-stored list of signals. Upon
comparison, the microcontroller determine and provide a digital signal to
connected digital display about the current gear.
[0034] The micro-controller may be an Electronic Control Unit (ECU) of the veh5 icle.
The microcontroller may be a separate controller for the gear detection. The
microcontroller is programmed controller to receive inputs and executed the
predefined instructions in the specified manner to give output. In an embodiment, the
micro-controller is coupled with a display unit provided on instrument panel of the
10 vehicle to display the output, i.e., current gear.
[0035] Referring to figure 4 and 3, the at least three sensors 204 are positioned
such that the sleeve surface 203 lies in the sensing area of the three sensors. Based
on the cylindrical hollow sleeve 203 combination with the gear shift shaft, six
distinct positions can be achieved via rotary and linear motions. These six
15 positions correspond to five forward and one reverse gear.
The cut outs 101a, 101b, 101c, 101d provided on the cylindrical hollow sleeve
203 surface in a specific pattern to generate six different sensor output positions.
The at least three sensors 203 are positioned on the gear shift guide case 202 in
triangular shape so that there are six different combinations of sensor outputs
20 corresponding to the six different sleeve positions for all six gears.
[0036] In an embodiment, to generate six different positions signals for the
sensors, the two vertical cutouts 101a, 101b and the square cutout 101c of the
cylindrical hollow sleeve 203 are relatively positioned in front of the at least three
magnetic field sensors 204 that are positioned in triangular shape, specifically, in
25 equilateral triangular shape. The at least three magnetic field sensors 204 generates
six different pattern based on position of the two vertical cutouts 101a, 101b and the
square cutout 101c of the cylindrical hollow sleeve 203.
[0037] Fig. 5a-5g shows six positions of the cylindrical hollow sleeve with
respect to the three gears for different gear selection and shifting. Fig. 5a shows
30 first gear detection with relative position of the cylindrical hollow sleeve with the
9
three magnetic sensors. The boxes 501, 502, 503 illustrates triangular position of
the three magnetic field sensors. The dark boxes indicate presence of
ferromagnetic metal, i.e., solid portion of the cylindrical hollow sleeve. The light
boxes indicate absence of the ferromagnetic metal, i.e., cutout portion of the
cylindrical hollow sleev5 e.
[0038] Referring to figure 5a which indicates that during first gear two sensors are
detecting absence of the sleeve and one sensor detect presence of the sleeve. Based on
the positions and presence/absence signals for 3 sensors a matrix is define with 0 and
1 where 0 indicates presence of the sleeve means magnetic field sensor detecting
10 ferromagnetic metal object and 1 indicates absence of the ferromagnetic metal object
means cutout provided in the cylindrical sleeve. Based on the signals of the three
magnetic field sensors 204, a signal is generated 010 which indicates first gear.
[0039] Similarly in figure 5b to 5g different signals are generated for different gears.
[0040] Fig. 5b indicates 001 for second gear.
15 [0041] Fig. 5c indicates 100 for third gear.
[0042] Fig. 5d indicates 000 for fourth gear.
[0043] Fig. 5e indicates 110 for fifth gear.
[0044] Fig. 5f indicates 101 for reverse gear.
[0045] Fig. 5g indicates 111 for neutral gear.
20 [0046] All signals are predefined in the micro-controller for real time detection. The
micro-controller receives the signals from the three magnetic field sensors and
compares these signals with the predefined or prestored signals and generate the
output.
[0047] The present system is explained for the six gear manual transmission. It
25 can be manufactured for seven gear manual transmission with slight modification
that are under the scope of the present subject matter.
[0048] The present system provides high reliability by using 3 sensors to detect
each gear position with combination of the optimized sleeve.
10
[0049] The present system is a robust contact less gear detection system where all
components are not in physical contact.
[0050] The present system is cost effective system as it uses only 3 sensors to
detect six gear position with simple and cost effective sleeve.
[0051] The term “vehicle” or “automobile” as used throughout this detail5 ed
description and in the claims refers to any moving vehicle that is capable of
carrying one or more human occupants or goods and is powered by any form of
energy. The term “vehicle” is a motor vehicle which includes, but is not limited
to: cars, trucks, vans, minivans, hatchback, sedan, MUVs, and SUVs.
10 [0052] The terms “comprises”, “comprising”, or any other variations thereof used
in the disclosure, are intended to cover a non-exclusive inclusion, such that a
device, system, assembly that comprises a list of components does not include
only those components but may include other components not expressly listed or
inherent to such system, or assembly, or device. In other words, one or more
15 elements in a system or device proceeded by “comprises… a” does not, without
more constraints, preclude the existence of other elements or additional elements
in the system or device.
[0053] It will be understood by those within the art that, in general, terms used
herein, and especially in the appended claims (e.g., bodies of the appended
20 claims) are generally intended as “open” terms (e.g., the term “including” should
be interpreted as “including but not limited to,” the term “having” should be
interpreted as “having at least,” the term “includes” should be interpreted as
“includes but is not limited to,” etc.). It will be further understood by those within
the art that if a specific number of an introduced claim recitation is intended, such
25 an intent will be explicitly recited in the claim, and in the absence of such
recitation no such intent is present. For example, as an aid to understanding, the
following appended claims may contain usage of the introductory phrases “at least
one” and “one or more” to introduce claim recitations. However, the use of such
phrases should not be construed to imply that the introduction of a claim recitation
30 by the indefinite articles “a” or “an” limits any particular claim containing such
11
introduced claim recitation to inventions containing only one such recitation, even
when the same claim includes the introductory phrases “one or more” or “at least
one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should
typically be interpreted to mean “at least one” or “one or more”); the same holds
true for the use of definite articles used to introduce claim recitations. In add5 ition,
even if a specific number of an introduced claim recitation is explicitly recited,
those skilled in the art will recognize that such recitation should typically be
interpreted to mean at least the recited number (e.g., the bare recitation of “two
recitations,” without other modifiers, typically means at least two recitations, or
10 two or more recitations). Furthermore, in those instances where a convention
analogous to “at least one of A, B, and C, etc.” is used, in general such a
construction is intended in the sense one having skill in the art would understand
the convention (e.g., “a system having at least one of A, B, and C” would include
but not be limited to systems that have A alone, B alone, C alone, A and B
15 together, A and C together, B and C together, and/or A, B, and C together, etc.).
In those instances where a convention analogous to “at least one of A, B, or C,
etc.” is used, in general such a construction is intended in the sense one having
skill in the art would understand the convention (e.g., “a system having at least
one of A, B, or C” would include but not be limited to systems that have A alone,
20 B alone, C alone, A and B together, A and C together, B and C together, and/or A,
B, and C together, etc.). It will be further understood by those within the art that
virtually any disjunctive word and/or phrase presenting two or more alternative
terms, whether in the description, claims, or drawings, should be understood to
contemplate the possibilities of including one of the terms, either of the terms, or
25 both terms. For example, the phrase “A or B” will be understood to include the
possibilities of “A” or “B” or “A and B.”
[0054] It will be further appreciated that functions or structures of a plurality of
components or steps may be combined into a single component or step, or the
functions or structures of one-step or component may be split among plural steps
30 or components. The present invention contemplates all of these combinations.
Unless stated otherwise, dimensions and geometries of the various structures
12
depicted herein are not intended to be restrictive of the invention, and other
dimensions or geometries are possible. In addition, while a feature of the present
invention may have been described in the context of only one of the illustrated
embodiments, such feature may be combined with one or more other features of
other embodiments, for any given application. It will also be appreciated from th5 e
above that the fabrication of the unique structures herein and the operation thereof
also constitute methods in accordance with the present invention. The present
invention also encompasses intermediate and end products resulting from the
practice of the methods herein. The use of “comprising” or “including” also
10 contemplates embodiments that “consist essentially of” or “consist of” the recited
feature.
[0055] Although embodiments for the present subject matter have been described
in language specific to structural features, it is to be understood that the present
subject matter is not necessarily limited to the specific features described. Rather,
15 the specific features and methods are disclosed as embodiments for the present
subject matter. Numerous modifications and adaptations of the system/component
of the present invention will be apparent to those skilled in the art, and thus it is
intended by the appended claims to cover all such modifications and adaptations
which fall within the scope of the present subject matter.

We claim:
1. A gear detection system (200) for manual transmission to detect gear
position in vehicle, the gear detection system (200) comprising:
a gear shift tower having a gear shift shaft (201) and a gear 5 shift
guide case (202);
characterized in that
a cylindrical hollow sleeve (203, 100) mounted on the gear shift
shaft (201), wherein the cylindrical hollow sleeve (203, 100) is housed by
10 the gear shift guide case (202);
at least three magnetic field sensors (204) positioned on the gear
shift guide case (202), wherein the at least three magnetic field sensors
(204) is positioned relatively with the cylindrical hollow sleeve (203, 100)
to generate magnetic field signals, wherein the at least three magnetic field
15 sensors (204) generates the magnetic field signals upon detection of the
the cylindrical hollow sleeve (203, 100);
a micro-controller configured to receive generated magnetic
signals, the micro-controller is to:
determine current gear based on the received magnetic signals.
20
2. The gear detection system (200) as claimed in claim 1, wherein the microcontroller
() is to:
based on the received magnetic signals, determine position of the
cylindrical hollow sleeve (203, 100) with respect to the at least three
25 magnetic field sensors (204); and
generate an output signal that indicates the current gear.
3. The gear detection system (200) as claimed in claim 2, wherein the
at least three magnetic field sensors (204) generates six different output signal
corresponding to six different cylindrical hollow sleeve (203, 100) positions for
30 detection of six gear positions.
14
4. The gear detection system (200) as claimed in claim 3, wherein the
microcontroller matches the position of the cylindrical hollow sleeve (203, 100)
with predefined cylindrical hollow sleeve (203, 100) position and determine the
current gear position.
5
5. The gear detection system (200) as claimed in claim 1, wherein the
cylindrical hollow sleeve (203, 100) is ferro-magnetic metal.
6. The gear detection system (200) as claimed in claim 1, wherein the
cylindrical hollow sleeve (203, 100) moves in combination of rotary and linear
10 motion during gear shift along with the gear shift shaft (201).
7. The gear detection system (200) as claimed in claim 1, wherein the
cylindrical hollow sleeve (203, 100) consist two vertical cutouts (101a, 101b)
along axis (Y) and one square cutout (101c) in between the two vertical cutouts
(101a, 101b).
15 8. The gear detection system (200) as claimed in claim 7, wherein the two
vertical cutouts (101a, 101b) and the square cutout (101c) of the cylindrical
hollow sleeve (203, 100) are relatively positioned in front of the at least three
magnetic field sensors (204), wherein the at least three magnetic field sensors
(204) generates a pattern based on position of the two vertical cutouts (101a,
20 101b) and the square cutout (101c) of the cylindrical hollow sleeve (203, 100).
9. The gear detection system (200) as claimed in claim 1, wherein the at
least three magnetic field sensors (204) are positioned in triangularly on the gear
shift guide case (202).
10. The gear detection system (200) as claimed in claim 1, wherein the
25 micro-controller is Electronic Control Unit (ECU) of the vehicle.