TECHNICAL FIELD
The present invention relates to an exterior switch assembly of a vehicle. More
specifically, the present invention relates to the door switch assembly of a vehicle.
BACKGROUND
In present times, keyless entry feature is in huge demand. For unlocking of vehicles,
exterior mounted switch assembly on the doors has been made operable without using
key or remote. The required circuitry is designed in electronic control of the vehicle.
The switch is mounted at the external body of the vehicle door and must be
completely resistant to water, dust and other contaminations. Prior art related to
existing switch for this application made use of four screws (S) to fasten the external
components of the switch assembly as shown in Figure101. The problem with the
prior is that it increases the assembly time and cost of manufacturing of the switch
Another prior art related to the switch uses internal locks for locking. However these
locks (L) are difficult to manufacture because an undercut (U) is formed below the
locks as shown in the Figure 1(d). Due to this undercut (U) it is difficult to
manufacture these locks and also the cost of manufacturing is high. As shown in the
Figures 1(a), 1(b), 1(c) and 1(d) in prior art two sliders are used for ejecting of locks,
hence the process used for manufacturing locks in existing switch is more complex
and more costly. The undercut (U) areas shown in the Figure 104 mark the areas when
the sliders run during the manufacturing of the component.
As shown in Figure 1(d) the direction of removal of slider in the existing switch is
more complex, since the sliders are first ejected horizontally and then be removed
vertically.
BRIEF DESCRIPTION OF FIGURES
Figure 1(a) illustrates the existing prior backdoor switch assemblies.
3
Figure 1(b) illustrates the sectional view of another existing backdoor switch
assembly
Figure 1(c) illustrates the assembly when rubber knob is insert moulded with the
casing.
Figure 1(d) illustrates the sectional view of sub assembly of casing and rubber knob of
the sub assembly showing in Figure 103.
Figure 2 shows an exploded view of the back door switch assembly according to an
embodiment of the present disclosure.
Figures 3, 4 and 5 illustrates bottom view, top view and assembled view of the
backdoor switch according to an embodiment of the present disclosure
Figure 6 illustrates the mounting provisions for mounting the switch assembly on the
vehicle according to an embodiment of the present disclosure
Figure 7 shows a sectional view along A-A of the switch assembly shown in Figure 4
Figure 8 illustrates sectional view along C-C of the switch assembly shown in Figure
7
Figure 9 shows sectional view along B-B of the switch assembly shown in Figure 8.
Figure 10(a)-10(c) illustrates details of first rib and second rib for locking the casing
and housing according to an embodiment of the present disclosure.
Figure 11 shows the direction in which slider tool is operated during the
manufacturing of the casing
SUMMARY
The present disclosure relates to a switch assembly for vehicle comprising a housing
accommodating a tact switch and a spring loaded slider, a casing adapted to be
secured with housing, a rubber knob interposed between the housing and the casing
and rubber knob is adapted to actuate under an external force to actuate the slider and
the tact switch. The casing comprises of a cover, a peripheral wall extending
4
perpendicular from the cover and a plurality of locking arms extending longitudinally
from the peripheral wall in which each locking arm is provided with a first rib
extending laterally inwardly. The housing comprises of a plurality of second rib
extending laterally outwardly from the exterior of the housing, each of which being,
engage able with the corresponding first rib in which the second rib and the first rib
are adapted to cooperate with each other to constrain removal of the casing from the
housing in longitudinal direction. The switch assembly for vehicle in which the first
rib of the casing comprises a first upper inclined face and first lower inclined face.
The second rib of the housing comprises a second lower inclined face and a second
upper inclined face. The second upper inclined face of the second rib and the first
lower inclined face of the first rib are adapted to cooperate with each other to allow
insertion of the locking arm on the second rib of the housing and the second lower
inclined face of the second rib and first upper inclined face of the first rib are adapted
to provide a predetermined locking overlap to constraint the removal of casing from
the housing in the longitudinal direction. The switch assembly for vehicle in which
second lower inclined face of the second rib has an angle (θ1) in the range 4° to 8 °
from the horizontal plane, and the second upper inclined face of the second rib has an
angle (θ2) in the range 70° to 75° from the horizontal plane. The present switch
assembly for vehicle wherein first lower inclined face of the first rib has an angle (θ’)
in the range 4° to 8 ° from the horizontal plane, and the first upper inclined face of the
first rib has an angle (θ3) in the range 50° to 60° from the horizontal plane. The
locking arm of each switch assembly tapers inwardly at a predetermined angle (θ4)
preferably in the range of 2° to 4 ° upon inserting the locking arm on the second ribs.
DESCRIPTION OF PRESENT DISCLOSURE
While the invention is susceptible to various modifications and alternative forms,
specific embodiment thereof has been shown by way of example in the figures
and will be described in detail below. It should be understood, however that it is not
intended to limit the invention to the particular forms disclosed, but on the contrary,
the invention is to cover all modifications, equivalents, and alternative falling within
the spirit and the scope of the invention as defined by the appended claims.
5
Before describing in detail embodiments it may be observed that the novelty
and inventive step that are in accordance with the present invention resides multifunction
ignition lock for two wheelers motor vehicles. It is to be noted that a person
skilled in the art can be motivated from the present invention and modify the
various constructions of assembly, which are varying from vehicle to vehicle.
However, such modification should be construed within the scope and spirit of the
invention. Accordingly, the drawings are showing only those specific details that are
pertinent to understanding the embodiments of the present invention so as not to
obscure the disclosure with details that will be readily apparent to those of
ordinary skill in the art having benefit of the description herein.
The terms “comprises”, “comprising”, or any other variations thereof, are intended
to cover a non-exclusive inclusion, such that a setup, device that comprises a
list of components does not include only those components but may include other
components not expressly listed or inherent to such setup or device. In other
words, one or more elements in a system or apparatus proceeded by “comprises… a”
does not, without more constraints, preclude the existence of other elements or
additional elements in the system or apparatus.
Accordingly, the main aim of the present invention is to provide a switch assembly
for keyless entry which addresses at least one of the problems associated. The term
‘keyless entry” herein refers to a facility to lock /unlock vehicle’s door without using
a key or without using remote switch of a car or any other vehicle.
In addition, the process of manufacturing of locks in the present switch assembly is
simpler than that used in the existing switch. In the present case, during the
manufacturing of locks, the slider prevents the flow of plastic material from flowing
into the undercut area of the locks, hence creating the desired shape of the locks.
The present disclosure provides a simple and cost effective moulding manufacturing
process solution. In the present switch assembly it is difficult to manufacture internal
locks in smaller size due to insufficient internal space and also due to the complexity
involved in the process. Hence it is required to provide the locks on the outside of the
switch. In the present disclosure inventors have designed the locks externally and do
not make use of sliders for ejecting the locks during their manufacturing which
6
reduces the assembly time, cost of manufacturing and process of manufacturing the
locks is easy. In the present disclosure snap locks are added within the boundaries of
the switch so that the size of the switch is not changed. Since the size of the switch is
small the position of the snap locks is required to be precise so that they did not
increase the overall size of the switch. The volumetric size of the switch have been
reduced. Inventors have designed the lock in such a way that the weight of the switch
is not increased. The material required during the manufacturing of the locks is less as
compared to the existing switch. Inventors also removed some extra material from the
housing to negate the weight added by the snap locks.
The present disclosure also solves the problem faced in the existing switches by
introducing four snap locks which ensures firm and effective assembly of said
external components of the switch assembly.
Figure 2 shows an exploded view of the back door switch assembly according to an
embodiment of the present disclosure. The present disclosure is described with
reference to the backdoor switch assembly, however, the switch assembly of the
present disclosure is not limited to only backdoor and may be used for other
applications such as front door switch assembly.
Referring to Figure 2, the back door switch (1) comprises a casing (2), a rubber knob
(3), a spring (5) loaded slider(4), tact switch(6) and housing(7). The housing (7)
comprises an interior and an exterior. The interior of the housing (7) is provisioned to
accommodate the tact switch (6) and the spring loaded slider (4). The tact switch (6)
is an electronic switch which activates when the rubber knob (3) is pressed or if there
is a definitive change in pressure. As soon as a pressure on the rubber knob (3) is
released, the circuit is broken. The spring loaded slider(4) having two ends, wherein
one end is connected with a rubber knob(3) and other end is received in the interior of
the housing(7) and moves inside the housing(7). The rubber knob (3) is interposed
between the housing (7) and the casing (2) and adapted to actuate under an external
force to actuate the slider (4) and the tact switch (6). A pair of terminals (8) is
provided in the housing (7) for completing the connection.
The casing (2) is adapted to be secured with the housing (7). In an embodiment, the
casing (2) may be secured with the housing (7) by means of snap locks(9).
7
The casing (2) has a imaginary axis X-X has a cover (9), a peripheral wall (10)
extending perpendicularly from the cover (9). The casing (2) is provided with a
plurality of locking arms (11) extending longitudinally from the peripheral wall (10).
The term ‘longitudinally’ herein refers to a direction parallel to the axis X-X. Each of
the locking arm (11) is provided with a first rib (13) extending laterally inwardly. The
term ‘laterally’ herein refers to a direction perpendicular to the axis X-X.
The exterior of the housing (7) comprises a plurality of second rib (14) extending
laterally outwardly from the housing engage able with the corresponding first rib(13)
for assembling the casing(2) with the housing(7). The first ribs(13) of the locking arm
of the casing(2) and the second ribs(14) of the housing(7) are adapted to cooperate
with each other so as to constrain removal of the casing(2) from the housing(7) in the
longitudinal direction once the first ribs(13) are engaged with the corresponding
second ribs(14).
Figures 3, 4 and 5, illustrate bottom view, top view and assembled view of the
backdoor switch according to an embodiment of the present disclosure, respectively.
Figures 3 and 5 illustrate position of locks (15) at the bottom of the switch, which
lock the casing with the housing. The said ‘locks’ are implemented by means of the
engagement between the first rib (13) and the second rib (14).
Figure 6 illustrates the mounting provisions for mounting the switch assembly on the
vehicle according to an embodiment of the present disclosure. As shown in Figure 6, a
pair of external locks is provided with the switch assembly for mounting the switch
assembly on the vehicle. Dotted lines shown in Figure 6 indicate the location of
mounting panel (16). Only the portion above the dotted line will be visible on the door
as the switch assembly is held between the pair of external locks.
Figure 7 shows a sectional view along A-A of the switch assembly (1) shown in
Figure 4. Figure 8 a sectional view along C-C of the switch assembly (1) shown in
Figure 7.
Referring to Figures 7 and 8, the housing (7) is provided with plurality of crushing
ribs (17) on to adjacent faces (herein after crushing rib faces) of the housing (7). The
crushing ribs (17) extend laterally from the crushing rib faces of the housing (7) and
8
adapted to abut with inner face of the casing (2). Faces of the housing opposite to the
crushing rib (17) faces are defined as arresting faces(18) which abut with
corresponding inner faces of the casing(2). The crushing ribs (17) and arresting faces
(18) ensure proper assembly of the casing (2) with the housing (7) and prevent any
relative motion between the casing (2) and the housing (7) for achieving precision and
firm locking. Crushing ribs (17) are provided in X and Y directions to remove any
free space due to tolerance stack up, ensuring that the assembly is tight fit.
In the existing switches, the locks fail under the external torque. The present switch
assembly solves the above problem of the existing switch. Crushing ribs(17) and the
arresting faces(18) as shown in the Figures 7 and 8, hold the casing (2) with the
housing(7) under external torque or force. These crushing ribs (17) prevent the
opening of locks under any given torque or coupled force (F) as shown in the Figure
8.
Figure 9 shows sectional view along B-B of the switch assembly shown in Figure 8. It
can be seen from the Figure 9, the casing (2) and rubber knob (3) are mounted over
housing sub assembly for locking. When the rubber knob(3) is placed in between the
casing(2) and the housing(7), an intentional interference(19) of 0.2 mm to 0.6 mm is
kept so that the locking of housing and casing are kept under tension. This
interference (18) also prevents opening, under impact or vibration, of lock between
the housing (7) and the casing (2). To prevent further compression of rubber, two
crushing ribs(17) each on either side are provided in the casing, which can be seen
from Figure 9.
Figure 10(a)-10(c) illustrates details of first rib (13) and second rib (14) for locking
the casing (2) and housing (7) according to an embodiment of the present disclosure.
Referring to Figures 10 (a)-10(c), the first rib (13) of the casing comprises a first
upper inclined face (20) and a first lower inclined face (21). The second rib (14) of the
housing (7) comprises a second upper inclined face (22 and a second lower inclined
face (23). The second upper inclined face (22) of the second rib (14) and the first
lower inclined face (21) of the first rib (13) are adapted to cooperate with each other
to allow insertion of the locking arm on the second rib of the housing. The second
lower inclined face (23) of the second rib (14) and first upper inclined face (20) of the
9
first rib(13) are adapted to provide a predetermined locking overlap (L2) to constrain
the removal of casing from the housing in the longitudinal direction.
As shown in Figure 10 (a), an angle between the second lower inclined face (23) of
the second rib (14) from the horizontal plane is θ1. In an embodiment, θ1 is in the
range of 4° to 6° to increase the extraction force of the switch. The force required to
open the lock by pulling it apart between the housing and the casing is increased has
increased significantly due to this angle θ1. Hence, the durability of the switch against
external impact and vibration is increased.
As shown in Figure 10(b), an angle between second upper inclined face (22) of the
second rib (14) from the horizontal plane is θ2 which is herein after also referred as
insertion angle θ2. It was observed that, if the insertion angle θ2, was kept too large, it
resulted in fracture of the locking arms of the casing. Hence, in an embodiment of the
present disclosure, the insertion angle θ2 is in the range of 70° to 75°, without
affecting the locking overlap (L2). The insertion angle θ2 provides gradual expansion
of locking arms while they are inserted on the second rib (14) of the housing (7). The
locking overlap (L2) may be defined as the surface area of the first upper inclined(21)
face of the first rib(13) and second lower incline face of the second rib which make
contact with each other. The locking overlap (L2) is suitable to prevent the locks from
opening. If the angle θ2 is increased beyond 75° (<90 °) then the locking overlap (L2)
is decreased and the locks can easily open under external stresses. And if θ2 is
decreased below 70° then the locks break during their insertion.
As shown in Figure 10a, an angle of the first lower inclined face (21) of the first rib
(13) from the horizontal plane is θ’. In an embodiment, θ’ is in the range of 4° to 8 °.
An angle of the first upper inclined face (20) of the first rib (13) from the horizontal
plane is θ3. In an embodiment, angle θ3 is in the range of 50° to 60° from the
horizontal plane and allows easy sliding of locks into position without requiring much
insertion force and complements the insertion angle θ2. If θ3 is below the specified
range then end portion of the locking arms (11) tend to bend inwards rather than
outward. If the locking arms (11) bend inwards then it will develop permanent
deformation and the locking will not be proper. If θ3 is above the specified range then
the same results in decreasing the locking overlap (L2). In an embodiment, the
10
locking overlap (L2) is in the range of 0.9mm to 1 mm. The length of the locking arm
(11) may be kept in the range of 4.7 mm to 6 mm so that angle θ2 and θ3 are at
minimum and locking overlap (L2) is maximized
Since the locking overlap (L2) was increased, the flexibility of the lock (15) is
required to be ensured so that lock (15) does not break when assembled. To increase
the flexibility of the lock(15) without compromising the fracture strength each locking
arm(11) tapers inwardly at a predetermined angle (θ4) preferably in the range of 2° to
4° upon inserting the locking arm(11) on the second ribs(14). In an embodiment,
thickness (t1)of the locking arm(11) is in the of 1.4 mm - 1.6 mm and thickness (t2) is
in the range of 1.2mm -1.4mm as shown in the Figure 10 (c). This taper improves the
flexibility of the locks without compromising their fatigue strength.
The angle θ4 affects the thicknesses of locks t1 and t2. If θ4 is increased beyond the
specified values then the thickness t2 decreases and the locking arm(24) become weak
and if the angle θ4 if decreased below the specified range then the thickness of the
locking arm increases which reduces the flexibility of the locks and the locking arms
(11) may break during insertion. Since the angle θ4 plays an important role in
maintaining regulating the dimensions of these thicknesses.
Figure 11 shows the direction in which slider tool is operated during the
manufacturing of the casing. To create the undercut of the locking arms four slider
tools are operated as shown in the Figure 11. These slider tools (24) prevent the flow
of plastic material from flowing into the undercut area of the locks, hence creating the
desired shape of the locks. As shown Figure 1 (d) the direction of removal of slider
tool (24) in case of existing switches is more complex, since the slider tools(24) are
first ejected horizontally and then be removed vertically. Hence the manufacturing of
locking arm of the present disclosure is simpler.
Some of the advantages of the switch assembly of the present disclosure are as
follows:
 Less assembly time
11
 Less parts inventory
 Cost effective
 Excellent product assembly which is achieved by inventive locking method.
 Complete water, dust and other contamination proof.
Equivalents:
The embodiments herein and the various features and advantageous details thereof are
explained with reference to the non-limiting embodiments in the description.
Descriptions of well-known components and processing techniques are omitted so as
to not unnecessarily obscure the embodiments herein. The examples used herein are
intended merely to facilitate an understanding of ways in which the embodiments
herein may be practiced and to further enable those of skill in the art to practice the
embodiments herein. Accordingly, the examples should not be construed as limiting
the scope of the embodiments herein.
The foregoing description of the specific embodiments will so fully reveal the general
nature of the embodiments herein that others can, by applying current knowledge,
readily modify and/or adapt for various applications such specific embodiments
without departing from the generic concept, and, therefore, such adaptations and
modifications should and are intended to be comprehended within the meaning and
range of equivalents of the disclosed embodiments. It is to be understood that the
phraseology or terminology employed herein is for the purpose of description and not
of limitation. Therefore, while the embodiments herein have been described in terms
of preferred embodiments, those skilled in the art will recognize that the embodiments
herein can be practiced with modification within the spirit and scope of the
embodiments as described herein.
Throughout this specification the word “comprise”, or variations such as “comprises”
or “comprising”, will be understood to imply the inclusion of a stated element, integer
or step, or group of elements, integers or steps, but not the exclusion of any other
element, integer or step, or group of elements, integers or steps.
12
The use of the expression “at least” or “at least one” suggests the use of one or more
elements or ingredients or quantities, as the use may be in the embodiment of the
disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles and the like that has
been included in this specification is solely for the purpose of providing a context for
the disclosure. It is not to be taken as an admission that any or all of these matters
form a part of the prior art base or were common general knowledge in the field
relevant to the disclosure as it existed anywhere before the priority date of this
application.
The numerical values mentioned for the various physical parameters, dimensions or
quantities are only approximations and it is envisaged that the values higher/lower
than the numerical values assigned to the parameters, dimensions or quantities fall
within the scope of the disclosure, unless there is a statement in the specification
specific to the contrary.
While considerable emphasis has been placed herein on the particular features of this
disclosure, it will be appreciated that various modifications can be made, and that
many changes can be made in the preferred embodiments without departing from the
principles of the disclosure. These and other modifications in the nature of the
disclosure or the preferred embodiments will be apparent to those skilled in the art
from the disclosure herein, whereby it is to be distinctly understood that the foregoing
descriptive matter is to be interpreted merely as illustrative of the disclosure and not
as a limitation.

CLAIMS:1. A switch assembly for vehicle (1) comprising,
a housing (7) comprising
- an interior accommodating a tact switch(6) and a spring(5) loaded slider(4) ;
- and an exterior
a casing (2) adapted to be secured with housing (7) ;
a rubber knob(3) interposed between the housing (7) and the casing(2) ;
the rubber knob (3) is adapted to actuate under an external force to actuate the slider(4) and the tact switch (6) ,
wherein, the casing (2) comprises ,
- a cover (9) ;
- a peripheral wall (10) extending perpendicular from the cover ;
- a plurality of locking arms (11) extending longitudinally from the peripheral wall; wherein each locking arm (11) is provided with a first rib(13) extending laterally inwardly ;
the housing (7) comprises,
- a plurality of second rib (14) extending laterally outwardly from the exterior of the housing, each of which being, engageable with the corresponding first rib(13) ; wherein the second rib (14) and the first rib (13) are adapted to cooperate with each other to constrain removal of the casing from the housing in longitudinal direction.

2. The switch assembly for vehicle as claimed in claim 1, wherein, the first rib(13) of the casing comprises
- a first upper inclined face (20)
- a first lower inclined face (21)

and second rib(14) of the housing(7) comprises
- a second lower inclined face (21)
- a second upper inclined face (22)

3. The switch assembly for vehicle as claimed in claim 2, wherein the second upper inclined face (22) of the second rib (14) and the first lower inclined face (21) of the first rib (13) are adapted to cooperate with each other to allow insertion of the locking arm (11) on the second rib (14) of the housing (7) and wherein second lower inclined face (21) of the second rib(14) and first upper inclined face (20) of the first rib (13) are adapted to provide a predetermined locking overlap (L2) to constraint the removal of casing (2) from the housing (7) in the longitudinal direction.

4. The switch assembly for vehicle as claimed in claim 2 wherein, second lower inclined face (21) of the second rib (14) has an angle (?1) in the range 4° to 8 ° from the horizontal plane, and the second upper inclined face (22) of the second rib (14) has an angle (?2) in the range 70° to 75° from the horizontal plane.

5. The switch assembly for vehicle as claimed in claim 2 wherein, first lower inclined face (21) of the first rib (13) has an angle (?’) in the range 4° to 8 ° from the horizontal plane, and the first upper inclined face (20) of the first rib (13) has an angle (?3) in the range 50° to 60° from the horizontal plane.

6. The switch assembly for vehicle as claimed in claim 1 and claim 2 wherein each locking arm (11) tapers inwardly at a predetermined angle (?4) preferably in the range of 2° to 4 ° upon inserting the locking arm (11) on the second ribs (14).