FORM 2

THE PATENTS ACT 1970
[39 OF 1970]
&
The Patents Rules, 2003

COMPLETE SPECIFICATION
[See section 10 and rule 13]

TITLE: “A SUSPENSION SYSTEM FOR A CABIN OF A VEHICLE”

NAME AND ADDRESS OF THE APPLICANT:

TATA MOTORS LIMITED, having address at Bombay House, 24 Homi Mody Street,
Hutatma Chowk, Mumbai 400 001 Maharashtra, India.
Nationality: INDIAN

The following specification particularly describes the invention and the manner in which it is to be performed.

TECHNICAL FIELD:
Present disclosure generally relates to a field of automobiles. Particularly, but not exclusively, the
present disclosure relates to a suspension system for a cabin of a vehicle to minimize vibrations
transmitted from a vehicle chassis to the cabin. Embodiments of the present disclosure also relates
5 to a front and rear suspension units to ensure stability of the vehicle on rough/uneven terrains.

BACKGROUND OF DISCLOSURE:
Heavy-duty vehicles such as tractor-trailers that transport freight generally are configured with a
cabin that is attached to a front portion of a vehicle chassis. The cabin also provides a central
10 location to control and operate interfaces along with other vehicle functions.
Conventionally, a rear side of the cabin is connected to the vehicle chassis through a cabin
suspension having a pair of vertical damping structures at its corners. As these vehicles typically
carry loads and traverse through different terrains there exists high level of bumpiness felt within
15 the cabin. Moreover, the vibrations or movements transmitted from the vehicle chassis to the cabin
becomes severe in cases of off-road conditions. Although, the existing cabin suspension is
typically configured to provide some reduction in noise and vibration transmission from the chassis
to the cabin. However, the cabin suspension does not mitigate higher amplitude jolts and vibrations
transmission to the cabin when the vehicle travels on rough or bumpy roads. Furthermore, as the
20 vehicle travels, the movement/vibration of the chassis induces the cabin to pitch, roll and bounce.
In particular, operation of the vehicles causes forces to be applied to the chassis of the vehicle
which, in turn, are transmitted to the cabin. This adversely affects comfort of an operator within
the cabin and results in fatigue which further leads to decrease in required daily vehicle travel.
25 The present disclosure is intended to overcome one or more above stated limitations.

SUMMARY OF THE DISCLOSURE:
One or more shortcomings of conventional suspension systems are overcome, and additional
30 advantages are provided through a suspension system for a cabin of a vehicle of the present
disclosure. Additional features and advantages are realized through the construction and arrangement of the components of the suspension system. Other embodiments and aspects of
the disclosure are described in detail herein and are considered a part of the claimed disclosure.
In one non-limiting embodiment of the present disclosure, a suspension system for a cabin of a
5 vehicle is disclosed. The suspension system comprises a chassis configured to receive the cabin
mounted on a portion of the chassis. A pair of coilovers are connected to the cabin and the
chassis. At least one first strut is pivotally connected to the pair of coilovers and oriented
laterally from the pair of coilovers. Aat least one bracket is rigidly coupled to a bottom end of
the pair of coilovers and the at least one first strut. The at least one bracket is configured to
10 transmit vibrations from the chassis to the at least one first strut and the pair of coilovers. The
pair of coilovers and the at least one first strut are configured to absorb vibrations transmitted
to the cabin during movement of the vehicle.
In an embodiment, each strut of the pair of coilovers comprises a damper and a coil spring
15 disposed around the damper to dampen the vibrations.
In an embodiment, the pair of coilovers is defined with a stiffness ranging from 3 Kg/mm to 4.5
Kg/mm.
20 In an embodiment, the pair of coilovers are positioned between the chassis and the bottom
portion of the cabin to uniformly distribute load of the cabin to the chassis.
In an embodiment, the at least one bracket comprises a mounting plate connected to the chassis
to couple the bottom portion of each of the pair of coilovers with the at least one bracket. A
25 connecting arm is fixedly connected to the mounting plate and extends upwardly from the
chassis. A link extends from a free end of the at least one bracket opposite the flat plate and the
link is configured to pivotally connect the at least one first strut.
In an embodiment, the suspension system comprises a front axle connected with a front
30 suspension unit. The front suspension unit is defined with a plurality of mono-leaf springs
connected at either ends of the front axle.

In an embodiment, the front suspension unit comprises a plurality of brackets extending from
the chassis to connect with the plurality of mono-leaf springs through a suitable fastening
mechanism.
In an embodiment, front suspension unit comprises at least one second strut disposed between the
5 chassis at one end and connected to a central portion of the plurality of mono-leaf springs at an
other end to dampen the vibrations.
In an embodiment, the suspension system comprises a rear axle connected with a rear suspension
unit, wherein the rear suspension unit is defined with at least one pair of multi-leaf springs
connected to either ends of the chassis and the rear axle and extend in a traverse direction of the
10 rear axle.
In an embodiment, the rear suspension unit further comprises at least one third strut connected to
a cross member of the chassis at one end and to the rear axle at an other end to dampen the
vibrations of the front suspension unit.
In an embodiment, the at least one pair of multi-leaf springs are defined with a stiffness ranging
15 between 110 kg/mm to 120kg/mm and the at least one third strut is defined with a damping coefficient ranging between 12Ns/mm to 16.5Ns/mm.
In an embodiment, the suspension system comprises a coupling member mounted on the chassis
and positioned proximate to the rear suspension unit.
In an embodiment, the coupling member is defined with a king-pin receiving slot located at a
20 predetermined distance in a range of 200 to 400 mm from a centre of the rear axle.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In
addition to the illustrative aspects, embodiments, and features described above, further aspects,
embodiments, and features will become apparent by reference to the drawings and the following
25 description.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS:

The novel features and characteristics of the disclosure are set forth in the appended description.
The disclosure itself, however, as well as a preferred mode of use, further objectives, and
advantages thereof, will best be understood by reference to the following description of an
illustrative embodiment when read in conjunction with the accompanying drawings. One or
5 more embodiments are now described, by way of example only, with reference to the
accompanying drawings wherein like reference numerals represent like elements and in which:
Fig. 1 illustrates a perspective view of a tractor-trailer vehicle along with its chassis and a cabin
supported thereon, in accordance with an embodiment of the present disclosure.
10
Fig. 2 illustrates a perspective view of a suspension system of a cabin of the vehicle, in
accordance with an embodiment of the present disclosure.
Fig. 3 illustrates a side view of the vehicle depicting a front suspension unit and a rear
15 suspension unit, a fluid delivery system with the fluid pressure regulator of Fig. 1, in accordance
with an embodiment of the present disclosure.
Fig. 4 illustrates a perspective view of the vehicle with the front suspension unit and the rear
suspension unit, in accordance with an embodiment of the present disclosure.
20
Figs. 5 and 6 illustrates a front and perspective views of the front suspension unit of the vehicle,
in accordance with an embodiment of the present disclosure.
Figs. 7 and 8 illustrates a perspective and front views of the rear suspension unit of the vehicle
25 of Fig. 1.
Fig. 9 illustrates a coupling member for mounting a trailer of the vehicle, in accordance with an
embodiment of the present disclosure.
30 Fig. 10 is a simulation of the tractor-trailer vehicle model, in accordance with an embodiment
of the present invention, in accordance with an embodiment of the present disclosure.
The figures depict embodiments of the disclosure for purposes of illustration only. One skilled
in the art will readily recognize from the following description that alternative embodiments of

the structures and methods illustrated herein may be employed without departing from the
principles of the disclosure described herein.

DETAILED DESCRIPTION:
While the embodiments of the disclosure are subject to various modifications and alternative
forms, specific embodiments thereof have been shown by way of example in the figures and
will be described below. It should be understood, however, that it is not intended to limit the
disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all
10 modifications, equivalents, and alternatives falling within the scope of the disclosure.
It is to be noted that a person skilled in the art would be motivated from the present disclosure
and modify an existing cabin suspension system for the purpose of minimizing vibration
transmission to the cabin. However, such modification should be construed within the scope of
15 the present disclosure. Accordingly, the drawings show only those specific details that are
pertinent to understand the embodiments of the present disclosure 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.
20 The terms “comprises”, “comprising”, or any other variations thereof used in the present
disclosure, are intended to cover a non-exclusive inclusion, such that a system, or a method,
which comprises a list of components does not include only those components but may include
other components not expressly listed or inherent to such system and the method. In other
words, one or more elements in the system, and the method preceded by “comprises… a” does
25 not, without more constraints, preclude the existence of other elements or additional elements
in the system and the method.
In the following description of the embodiments of the disclosure, reference is made to the
accompanying figures that form a part hereof, and in which are shown, by way of illustration,
30 specific embodiments in which the present disclosure may be practiced. These embodiments
are described in sufficient detail to enable those skilled in the art to practice the present
disclosure, and it is to be understood that other embodiments may be utilized and that, changes

may be made without departing from the scope of the present disclosure. The following
description is, therefore, not to be taken in a limiting sense.
Embodiments of the present disclosure discloses a suspension system for a cabin of a vehicle.
5 Conventionally, a rear side of the cabin is connected to the vehicle chassis through a cabin
suspension having a pair of vertical damping structures in its corners. As these vehicles typically
operate on off-road surfaces or fields having a high level of bumpiness, the vibrations or
movements transmitted from the vehicle chassis to the cabin becomes severe. Although, the
existing cabin suspension is typically configured to provide some reduction in noise and vibration
10 transmission from the chassis to the cabin. However, the cabin suspension does not mitigate higher
amplitude jolts and vibrations transmission to the cabin when the vehicle travels on rough or
bumpy roads. Furthermore, as the vehicle travels, the movement/vibration of the chassis induces
the cabin to pitch, roll and bounce. In particular, operation of the vehicles causes forces to be
applied to the chassis of the vehicle which, in turn, are transmitted to the cabin. This adversely
15 affects comfort of an operator within the cabin and results in fatigue which further leads to decrease
in required daily vehicle travel.
In view of the above, a suspension system for a cabin of a vehicle is disclosed. The suspension
system comprises a chassis configured to receive the cabin mounted on a portion of the chassis.
20 A pair of coilovers are connected to the cabin and the chassis. At least one first strut is pivotally
connected to the pair of coilovers and oriented laterally from the pair of coilovers. Aat least one
bracket is rigidly coupled to a bottom end of the pair of coilovers and the at least one first strut.
The at least one bracket is configured to transmit vibrations from the chassis to the at least one
first strut and the pair of coilovers. The pair of coilovers and the at least one first strut are
25 configured to absorb vibrations transmitted to the cabin during movement of the vehicle. This
configuration of the at least one bracket and the at least one first strut absorbs the vibrations
generated on the chassis while the vehicle is taking turns or while the vehicle is subjected to
movement in yaw direction upon travelling on uneven roads. Advantageously, this eliminates
the jolts and jerks experienced by a driver and passengers inside the cabin, thereby offering a
30 smooth ride without any fatigue to the driver and the passengers. Further, the at least one strut
positioned between the cabin and the chassis supports weight of the cabin and distributes the load of the cabin uniformly on the chassis. This provides stability to the vehicle and prevents
the cabin from pitching, rolling, and bouncing during movement of the vehicle.
The following paragraphs describe the present disclosure with reference to Figures. 1 to 10. In the
5 Figures, the same element or elements which have similar functions are indicated by the same
reference signs.
Referring to Fig. 1 perspective view of a tractor-trailer vehicle {hereinafter referred to as the
vehicle (100)] as illustrated. The vehicle (100) comprises a chassis (102) supported by a plurality
10 of wheels (126, 204, 900). The chassis (102) includes a pair of longitudinal members (104, 106)
and a plurality of cross members (118, 120, 122, 124) extending transversely between the pair of
longitudinal members (104, 106). A front axle and a rear axle are connected to the wheels and
extends transversely below the chassis. The front and rear axles bear weight of the vehicle (100)
along with any payload/cargo and configured to transmit power from an engine (not shown in
15 Figs.) of the vehicle (100) to the plurality of wheels (126, 204, 900) while maintaining the position
of the plurality of wheels (126, 204, 900) relative to each other and to the vehicle body (not shown
in Figs.). A suspension system (112) for a cabin (114) of the vehicle (200) is mounted on the
chassis (102) for damping the vibrations of the cabin (114) during movement of the vehicle (100)
on rough and irregular terrains.
20
Referring to Fig. 2, the suspension system (112) [hereinafter referred to as “the system (112)”] for
the cabin (114) is disposed between the cabin (114) and the chassis (102). The suspension system
comprises a pair of coilovers (706) connected to a bottom portion of the cabin (114). Each coilover
(706) of the pair of coilovers (706) is defined with a top hat/top mount (706a) and a bottom mount
25 (706b). The top mount is connected to the bottom portion of the cabin and the bottom mount (706b)
is connected to the pair of longitudinal members (104, 106) of the chassis (102). Each coilover
(706) comprises a damper (707) and a coil spring (709) wound around the damper (707) to dampen
the vibrations subjected on the damper (707). The damper (707) is defined as a flexible structure
and may be filled with an oil or a gas to dissipate heat produced upon continuous motion of the
30 damper. The damper is configured to absorb shock loads and damp the movement of the coil spring
(709) brings it back to the normal position. In an embodiment, the top mount is fastened to the
cabin through a suitable fastening mechanism such as but not limited to brackets, nuts and bolts,

screws rivets etc. In an embodiment, the damper may be manufactured of stainless steel and
however this cannot be construed as a limitation and the damper may be manufactured of any
suitable material based on the requirement. In an embodiment, the pair of coilovers (706) is defined
with a stiffness ranging from 3 Kg/mm to 4.5 Kg/mm. At least one first strut (702) is pivotally
5 connected to the pair of coilovers (706) and oriented laterally from the pair of coilovers (706). In
an embodiment, the at least one first strut (702) The at least one first strut (702) is configured to
dampen/absorb vibration force exerted by a road on the vehicle (100) in a lateral direction, also
referred as Y direction (as shown in Fig.1). The at least one first strut (702) is manufactured of a
polymeric material or metallic material based on the requirement. The at least one first strut (702)
10 is defined with a damping co-efficient in a range of 3.5Ns/mm to 5 Ns/mm. Further, at least one
bracket (708) is rigidly connected to the bottom mount (706b) of the pair of coilovers (706) at one
end and to the at least one first strut (702) at another end of the at least one bracket (708). The at
least one bracket (708) is configured to transmit vibrations from the chassis (102) to the at least
one first strut (702) and the pair of coilovers (706). The at least one bracket (708) is defined with
15 a mounting plate (712) connected to the chassis (102) to couple the bottom mount (706b) of each
of the pair of coilovers (706) with the at least one bracket (708). The mounting plate extends
vertically from the chassis (102) and is fastened to the chassis by fasteners such as nuts and bolts,
rivets, screws etc. A connecting arm (711) is fixedly connected to the mounting plate (712) and
extends upwardly from the chassis (102). The connecting arm (711) extends angularly from the
20 chassis (102) towards the cabin (114). In an embodiment, the connecting arm may be tapered in
configuration with its width reducing away from the mounting plate (712). A link (714) extends
from a free end of the at least one bracket (708) opposite the flat plate (714). The link (714) is
configured to pivotally connect the at least one first strut (702) with the at least one bracket (708).
The at least one bracket (708) may be manufactured by a stainless steel material or any other
25 metallic material based on the requirement. The pair of coilovers (706) and the at least one first
strut (702) are configured to absorb vibrations transmitted from the chassis (102) to the cabin (114)
during movement of the vehicle (100) in rough terrains and roads having undulations.
Advantageously, this minimizes jolts and jerks experienced by occupants inside the cabin (114)
and offers smooth and comfortable ride. Further, the system (112) is also cost-effective and
30 facilitates an enhanced level of vibration isolation for the cabin (114).

Referring to Figs. 3 and 4, the suspension system (112) further comprises a front suspension unit
(108) and a rear suspension unit (110) mounted to the front axle (200) and the rear axle (202)
respectively. The front suspension unit (108) is mounted on either sides of the front axles
connecting the respective wheels (204) of the front axle (200) and the chassis (102). Similarly, the
5 rear suspension unit (110) is mounted on either sides of the rear axle (202) connecting the
respective wheels (126) of the rear axle (202) and the chassis (102). Further, a coupling member
(116) (fifth wheel coupling) is pivotally coupled to the chassis (102) and positioned proximate to
the rear suspension unit (110). The coupling member (116) is coupled to the plurality of cross
members (120) at a rear end of the chassis (102) through the suitable fasteners. The coupling
10 member (116) is defined with a king-pin receiving slot (132) located at a predetermined distance
in a range of 200 to 400 mm from a center (802) of the rear axle (202). The king-pin (not shown
in Figs.) is attached to a trailer (128) (shown in Fig. 10) of the vehicle (100) to secure within the
king pin receiving slot (132) of the coupling member (116). The coupling member (116) is
configured to receive and support the trailer (128). The coupling member bears the weight of the
15 trailer (128) and also enables to pivot the trailer (128) with respect to the chassis (102) upon
requirement.
Now referring to Figs. 5 and 6, a front view of the front suspension unit (108) is illustrated. The
front suspension unit (108) is defined with a plurality of mono-leaf springs (408, 410, 412, 414)
20 connected at either ends of the front axle (200). Each of the plurality of mono-leaf springs are
uniform in cross-section and are connected together by a connector or a bracket (415) at both ends
to form a front suspension assembly (300). The plurality of mono-leaf springs (408, 410, 412, 414)
are configured to provide required damping effect and load bearing capacity to the vehicle (100).
In an embodiment, each mono-leaf spring of the plurality of mono-leaf springs (408, 410, 412,
25 414) is defined with the stiffness ranging between 20 kg/mm to 25kg/mm. A plurality of brackets
(406, 416, 418) are pivotally coupled to the longitudinal members (104, 106) of the chassis (102)
and extend downwardly from the chassis (102) to connect with the plurality of mono-leaf springs
(408, 410, 412, 414) at their ends through the suitable fasteners. In an embodiment, a pivot bracket
(422) is used to connect the plurality of brackets with the plurality of mono-leaf springs (408, 410,
30 412, 414) at one end. The front suspension unit (108) further comprises at least one second strut
(420) disposed between the chassis (102) at one end and connected to a central portion of the

plurality of mono-leaf springs (408, 410, 412, 414) at other end. In an embodiment, the at least
one second strut (420) is pivotally coupled to the chassis (102). The at least one second strut (420)
is configured to dampen the vibrations of the front suspension unit (108). The at least one second
strut (420) is fitted with a bump-stopper (426) to facilitate an enhanced damping characteristics,
5 high ride quality, high stability, and controllability for the vehicle (100). In an embodiment, the at
least one second strut (420) is defined with a damping co-efficient ranging between 12N/s to 16.5
N/s. An anti-roll bar (400) is connected to the at least one second strut (420) at one end by a Ubolt and nut (421) and to the chassis (102) at the other end. The anti-roll bar (400) is defined with
a linkage such as an anti-roll bar (ARB) drop link comprising two links (423, 424) interconnected
10 to each other. The ARB drop link is configured to arrest the vehicle (100) articulation during travel.
The anti-roll bar (400) is configured to reduce roll of the cabin (114) relative to the road surface
and minimizes the pitching of the cabin (114).
Referring to Figs. 7, 8 and 9, a perspective view and the side views of the rear suspension unit
15 (110) is illustrated. The rear suspension unit (302) is defined with at least one pair of multi-leaf
springs (602) connected to either ends of the longitudinal members (104, 106) of the chassis (102)
and to the rear axle (202). The at least one pair of multi-leaf springs (602) are arranged in a traverse
direction of the rear axle (202) to form a rear suspension assembly (604). Each of the pair of multileaf springs (6020 are joined with each other by suitable brackets to work in tandem with each
20 other. In an embodiment, the pair of multi-leaf springs (602) is defined with a predefined stiffness
coefficient ranging between 110kg/mm to 120 kg/mm. At least one third strut (600) is connected
to the cross member (122) at one end and other end is attached to the rear axle (202) through a
predefined structural member (608) such as a longer bolt. Specifically, as per an illustrated
embodiment, one end of the at least one third strut (600) of the each of the rear vehicle suspension
25 (110) is connected to the cross-member (122) and its other end is connected to a differentialgearbox (604) through a mounting bracket (606). In an embodiment, the at least one third strut
(600) is defined with a predefined damping coefficient ranging between 12Ns/ to 16.5 Ns/mm. In
an embodiment, one of the pair of multi-leaf springs (602) may be provided with auxiliary leaf
springs (610) having a predefined number of springs of a predefined stiffness. In an embodiment,
30 the plurality of auxiliary springs (610 may include 9 leafs of 7 leafs with a predefined thickness of
12mm and 2 leafs with a predefined thickness of 11mm.

Referring to Fig. 10 which illustrates a simulation tractor-trailer vehicle model (130). In an
embodiment, a simulation tractor-trailer vehicle model (130) is developed using MATLAB for
digitally determining the predefined RMS value for the vehicle cabin (114) that can be configured
5 for reducing driver fatigue 30 drastically and improved ride and comfort. The simulation tractortrailer vehicle model (130) comprises the suspension system (112) along with front suspension
unit (108) and the rear suspension unit (110) mounted to the chassis (102). As per the tractor-trailer
vehicle simulation model, a fixed-type vehicle cabin seat is advantageous in facilitating an
improved cabin (114) damping.
10
In an embodiment, the number of plurality of mono-leaf springs (408, 410, 412, 414) and the pair
of multi-leaf springs (602) are selected based on the requirement and type of vehicle (100) on
which the system (112) is installed.
15 The system (112) of the present disclosure provides required vibration damping to the cabin (114)
compared to a four point suspension system which generally requires more components and
installation space. Therefore, the system (112) of the present disclosure includes lesser number of
components which reduces cost of manufacture while providing good damping properties.
20 The at least one first strut (702) of the system (112) provides damping of vibrations transmitted
from the chassis (102) to the cabin (114) during the movement of the vehicle in Y direction or yaw
direction, thereby isolating the cabin (114) from the vibrations which results in smoother ride even
in rough terrains.
25 The stiffness of the plurality of mono-leaf springs (408, 410, 412, 414), the pair of multi-leaf
springs (602) along with the damping co-efficient of the at least one first strut (702) and the at least
one second strut (420) and the at least one third strut (600) of the system (112) cumulatively
corresponds to a predefined desirable root mean square (RMS) value for a cabin seat (not shown
in Figs.) in a range of 1.6 to 1.8 m/s2
. Further, the predefined desirable vehicle RMS value for a
driver seat is 1.6 m/s2
30 and the predefined desirable vehicle RMS value for a co-driver seat is 1.8
m/s2

The system (112) of the present disclosure minimizes the jerks and jolts experienced by the
occupants within the cabin (114) and ensures smooth ride for prolonged travel periods of the
vehicle (100).

Reference numerals:
Referral numeral Description
100 Vehicle
102 Chassis
104 Left longitudinal member
106 Right longitudinal member
108 Front suspension unit
110 Rear suspension unit
112 Suspension system for a cabin
114 Cabin
116 Coupling member
118, 120, 122, 124 Plurality of cross members
126, 204, 900 Plurality of wheels
128 Trailer
130 Simulation tractor-trailer vehicle model
132 King-pin receiving slot
200 Front axle
202 Rear axle
300 Front suspension assembly
302 Rear suspension assembly
400 Anti-roll bar
402 Pivot attachment point
404 Linkage
406, 416, 418 Plurality of brackets
408, 410, 412, 414 Plurality of Mono-leaf springs
415 Connector/bracket
420 At least one second strut
421 U-bolt and nut
422, 423 Two links
426 Bump stopper
600 At least one third strut
602 Plurality of multi-leaf springs
604 Differential-Gear box
606 Mounting bracket
608 Fastening member
610 Plurality of auxiliary springs
700 Cabin suspension assembly
702 At least one first strut
704 Pivot attachment point
706 Pair of coilovers
706a Top hat/top mount
706b Bottom mount
708 At least one bracket
710 Mounting bracket
711 Connecting arm
712 Mounting plate
714 Link
800 King-pin
802 Rear axle centre

EQUIVALENTS
With respect to the use of substantially any plural and/or singular terms herein, those having
skill in the art can translate from the plural to the singular and/or from the singular to the plural
5 as is appropriate to the context and/or application. The various singular/plural permutations may
be expressly set forth herein for sake of clarity.
While various aspects and embodiments have been disclosed herein, other aspects and
embodiments will be apparent to those skilled in the art. The various aspects and embodiments
10 disclosed herein are for purposes of illustration and are not intended to be limiting

We Claim:

1. A suspension system (112) for a cabin (114) of a vehicle (100), the suspension system(112) comprising:
a chassis (102) configured to receive the cabin (114), wherein the cabin (114) is mounted on a portion of the chassis (102);
a pair of coilovers (706) connected to the cabin (114) and the chassis (102);
at least one first strut (702) pivotally connected to the pair of coilovers (706) and oriented laterally from the pair of coilovers (706);
at least one bracket (708) rigidly coupled to a bottom mount (706b) of the pair of coilovers (706) and the at least one first strut (702), wherein the at least one bracket (708) is configured to transmit vibrations from the chassis (102) to the at least one first strut (702)
and the pair of coilovers (706); and
wherein the pair of coilovers (706) and the at least one first strut (702) are configured to dampen vibrations transmitted to the cabin (114) during movement of the vehicle.

2. The suspension system (112) as claimed in claim 1, wherein each coilover (706) of the pair of coilovers (706) comprises a damper (707) and a coil spring (709) disposed around the damper (707) to dampen the vibrations.

3. The suspension system (112) as claimed in claim 1, wherein the pair of coilovers (706) is defined with a stiffness ranging from 3 Kg/mm to 4.5 Kg/mm and the at least one first strut (702) is defined with a damping co-efficient in a range of 3.5Ns/mm to 5 Ns/mm.

4. The suspension system (112) as claimed in claim 1, wherein the pair of coilovers (706) are positioned between the chassis (102) and the bottom portion of the cabin (114) to uniformly distribute load of the cabin (114) to the chassis (102).

5. The suspension system (112) as claimed in claim 1, wherein the at least one bracket (708) comprises:
a mounting plate (712) connected to the chassis (102) to couple the bottom portion of each of the pair of coilovers (706) with the at least one bracket (708);

a connecting arm (711) fixedly connected to the mounting plate (712) and extends upwardly from the chassis (102); and
a link (714) extending from a free end of the at least one bracket (708) opposite the flat plate (714), the link (714) is configured to pivotally connect the at least one first strut (702).

6. The suspension system (112) as claimed in claim 1, comprises a front axle (200) connected with a front suspension unit (108), wherein the front suspension unit (108) is defined with a plurality of mono-leaf springs (408, 410, 412, 414) connected at either ends of the front
axle (200).

7. The suspension system (112) as claimed in claim 6, wherein the front suspension unit (108) comprises a plurality of brackets (406, 416, 418) extending from the chassis (102) to connect with the plurality of mono-leaf springs (408, 410, 412, 414) through a suitable fastening mechanism.

8. The suspension system (112) as claimed in claim 7, wherein the front suspension unit (108) comprises at least one second strut (420) disposed between the chassis (102) at one end and connected to a central portion of the plurality of mono-leaf springs (408, 410, 412,
414) at an other end to dampen the vibrations.

9. The suspension system (112) as claimed in claim 6, wherein the front suspension unit (108) further comprises an anti-roll bar (400) pivotally coupled with the plurality of mono-leaf springs (408, 410, 412, 414) at one end and fixedly connected to the chassis (102) at the
other end.

10. The suspension system (112) as claimed in claim 6, wherein the plurality of mono-leaf springs (408, 410, 412, 414) are defined with a stiffness ranging between 20 kg/mm to 25kg/mm and the at least one second strut (420) is defined with a damping co-efficient
ranging between 12Ns/mm to 16Ns/mm.

11. The suspension system (112) as claimed in claim 1, comprises a rear axle (202) connected with a rear suspension unit (110), wherein the rear suspension unit (302) is defined with at least one pair of multi-leaf springs (602) connected to either ends of the chassis (102) and
the rear axle (202).

12. The suspension system (112) as claimed in claim 12, wherein the rear suspension unit (110) further comprises at least one third strut (600) connected to a cross member (122) of the chassis (102) at one end and to the rear axle (202) at an other end to dampen the vibrations
of the front suspension unit (108).

13. The suspension system (112) as claimed in claim 12, wherein the at least one pair of multi10 leaf springs (602) are defined with a stiffness ranging between 110 kg/mm to 120kg/mm and the at least one third strut (600) is defined with a damping co-efficient ranging between 12Ns/mm to 16.5Ns/mm.

14. The suspension system (112) as claimed in claim 1, comprises a coupling member (116) pivotally coupled to the chassis (102) and positioned proximate to the rear suspension unit (110).

15. The suspension system (112) as claimed in claim 15, wherein the coupling member (116) is defined with a king-pin receiving slot (132) located at a predetermined distance in a range of 200 to 400 mm from a centre (802) of the rear axle (202).

Dated this on 17
th May 2024
NIKHIL SRINIVASA REDDY
25 OF K & S PARTNERS
AGENT FOR THE APPLICANT(S)
IN/PA- 2127
-Digitally signed and filed through E-filing