DESC:FORM 2
The Patent Act 1970
(39 of 1970)
&
The Patent Rules, 2005

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

TITLE OF THE INVENTION
“TORQUE TRANSMISSION DEVICE FOR TWO AND THREE WHEELED VEHICLES”

Endurance Technologies Limited
E-92, M.I.D.C. Industrial Area, Waluj,
Aurangabad – 431136, Maharashtra, India

The following specification particularly describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of Invention

[001] The present invention relates to a torque transmission device having a plurality of friction plates and steel plates for two and three wheeled vehicles. More particularly, the present invention relates to an optimized and compact design of a torque transmission device having a driving and driven components along with a stack of multiple friction plates and steel plates.

Background of the Invention

[002] The torque transmission device is an important sub-system of the vehicle powertrain and mainly used for transmitting and cutting off the torque from the crankshaft to the main shaft. The primary function of the torque transmission device is to transmit torque from the engine to the transmission / gear box while allowing to shift gear smoothly by disengaging engine and transmission momentarily. The torque transmission device also acts as a fuse to protect engine from excessive back torque from the vehicle in coasting condition. The torque transmission device with a plurality of friction plates and steel plates is one of the most prominent sub-system which is being used in two and three wheeled vehicles from many years. In these devices, there is an arrangement of alternate friction plates and steel plates placed alternative to each other which helps in torque transmission. However, such arrangements not only require higher number of steel plates and friction plates but higher clamp load as well which significantly increases the clutch lever effort and drag value of the torque transmission device. This also leads to increase mass moment of inertia leading to judder / vibrations in the torque transmission device.
[003] Hence, to address the above mentioned issues, there is a long pending unmet requirement of providing an intelligent and uniquely designed torque transmission device having uniquely profiled driving and driven elements for two and three wheeled vehicles that would reduce the number of friction plates and clutch lever efforts, improve the heat dissipations, reduces the drag and enhances the performance of the torque transmission device imparting superior ride and comfort to the vehicle user.

Objectives of the Invention

[004] The main objective of the present invention is to provide an optimized torque transmission device for two and three wheeled vehicles.

[005] Further, the objective of the present invention is to provide a torque transmission device having a uniquely profiled driving element and driven element that significantly reduces the handle lever effort of the torque transmission device for two and three wheeled vehicles in accordance of the present invention.

[006] Yet, the objective of the present invention is to provide a torque transmission device having a uniquely profiled driving element and driven element that reduces the plate stacks by 30 - 50% in accordance of the present invention.

[007] Yet, the objective of the present invention is to provide a torque transmission device having a uniquely profiled driving element and driven element that enables it use effectively and comfortably without any limitation where the diameter of the torque transmission device platform is less than 110 mm.
[008] Still, another objective of the present invention is to provide a torque transmission device having a driving element and driven element wherein these elements have uniquely profiled oil paths carved therein that facilitates an efficient heat dissipation from torque transmission device.

[009] Further, the objective of the present invention is to provide a torque transmission device having a driving element and driven element wherein these elements are configured to have uniquely profiled and optimized guides that enhance the performance and life of the torque transmission device.

Brief Description of the Drawings

[0010] This invention is illustrated in the accompanying drawings, throughout which like reference letters / numerals indicate corresponding parts in the various figures. The embodiments herein and advantages thereof will be better understood from the following description when read with reference to the following drawings, wherein

[0011] Figure 01 discloses the exploded view of the torque transmission device in accordance with the present invention.

[0012] Figures 02a and 02b show the perspective front view of the driving element of the torque transmission device of the present invention.

[0013] Figure 03 shows the perspective rear view of the driving element of the torque transmission device of the present invention.
[0014] Figure 04 shows the perspective front view of the driven element of the torque transmission device of the present invention.

[0015] Figures 05a and 05b show the perspective rear view of the driven element of the torque transmission device in accordance with the present invention.

[0016] Figures 06a and 06b show the front and top sectional views of the driving element and driven element in assembled condition of the torque transmission device in accordance with the present invention.

[0017] Figures 06c and 06d show the front sectional views of the driving element and the driven element in drive side assist condition and kick side assist condition, respectively in accordance with the present invention.

[0018] Figure 07 discloses the isometric assembled view of the torque transmission device in accordance with the present invention.

Detailed Description of the Present Invention

[0019] The invention will now be described in detail with reference to the accompanying drawings which must not be viewed as restricting the scope and ambit of the invention. In accordance with the disclosed embodiment of the present invention, referring to Fig. 1, the torque transmission device (300) for a two and three wheeled vehicles comprises of a housing assembly (100) and a clutch plate assembly (200). The clutch plate assembly (200) comprises of a driving element (20), a plate stack (30), a driven element (40), a plurality of retaining springs (50), an anti-centrifugal plate (60) and a plurality of fastening means (70). The said fastening means are selected from bolts, studs, and screws. The plate stack (30) comprises of friction plates (30A) and steel plates (30B) arranged alternatively.

[0020] The housing assembly (100) is includes a primary gear (105), and a housing (110). The housing (110) is configured to have a circumferential cylindrical body (110CP) protruding out from a flat surface (110F) of the housing (110) in its circumferential direction. The housing (110) is configured to have a cavity (110C) in front side (110FS) of the housing (110) and the circumferential cylindrical body (110CP) is configured to have a plurality of housing windows (115) for mounting of friction plates (30A) with matching outer projections (315) of the friction plates (30A) (refer Fig. 1). The primary gear (105) is fixed to the flat surface (110F) in a rear side (110R) of the housing (110) by a suitable fixing means. The primary gear (105) of the housing (110) receives the torque from the crank shaft of an engine (not shown in the figure) and transfers the torque to the housing (110) through a damping system (not shown in the figure).

[0021] The clutch plate assembly (200) comprises of a driving element (20), a plate stack (30), a driven element (40), a plurality of retaining springs (50), an anti-centrifugal plate (60) and a plurality of fastening means (70). The driving element (20) is configured to have an annular disc portion (20D) and a cylindrical projection (20C) wherein the cylindrical projection (20C) is integral to the disc portion (20D) and projects away from the front face (20F) of the said disc portion (20D). The said cylindrical projection (20C) is configured to have a set of splined portion (20SP) having a plurality of splines (21ST) formed at a regular interval on the outer peripheral surface of the said cylindrical projection (20C). The said splines (20ST) receives the stack of steel plates (30B) and friction plates (30A) thus facilitating the axial movement of the plate stack (30) thereby. The splined portion (20SP) is configured to have an additional projection length (21AL) wherein the said additional length extension (21AL) facilitates the guiding of the plate stack (30) and prevent the fall out of the friction / steel plates off the driving element (20) thereby.

[0022] The disc portion (20D) of the driving element (20) is configured to have a plurality of rectangular pockets (20P) formed at its rear face (20R). The pockets (20P) are formed at an equiangular distance to each other and may be selected from any suitable geometry viz. circular, triangular, square trapezoidal etc. wherein the said pockets (20P) facilitates the weight reduction of the driving element (20). The disc portion (20D) has at least three V-profiled tabs (20VT) projecting from the inner circumferential edge of the rear face (20R) and towards the center of the said disc portion (20D). The V-profiled tabs (20VT) are formed at an angle of 120° from each other. The said tabs (20VT) has a circular arc segmented face (20G) wherein the said face (20G) is configured to prevent the misalignment of the driven element (40). Further, the disc portion (20D) of the driving element (20) is configured to have at least three cylindrical lugs (21L) projecting out from the tabs (20VT) and orthogonally away from the front face (20F) of the said driving element (20). The said lugs (21L) are positioned at an equal angular distance from each other. Each of the lugs (21L) is configured to have a threaded profiled (21BT) bore on its top face (21T).

[0023] Further, the disc portion (20D) of the driving element (20) is configured to a have at least three V-profiled cam projections (21P) and each of the V-profiled cam projections (21P) projects out from the V-profiled tabs (21VT) and merges with the respective lug (21L) of the said driving element (20) form a stepped profile (SP) at the base of the said lug (21L) from the inner side. The said projections (21P) are formed in a manner such that the projections (21P) extends towards the centre of the driving element (20) from the inner circumferential edge of the cylindrical projection (20C) and the lugs (21L) are positioned at the centre of the said cam projections (21P). Further, each of the cam projections (21P) of the driving element (20) is configured to have an oil pocket (21PT) wherein the said oil pocket (21PT) is a V-profiled trench formed at the outer peripheral surface of the cylindrical projection (20C). The said oil pockets (21PT) has tapered walls (21ST) forming a taper angle (a) with the vertical wherein the said taper angle (a) ranges from 30 degrees to 90 degrees. The oil pockets (21PT) acts like a bucket and throws the oil to the stack plate (30) by scooping it out from the housing (110) during the working of the torque transmission device (300).

[0024] The cam projections (21P) are positioned around the inner circumferential edge of the cylindrical projection (20C) in such a way that they are equidistantly spaced apart from each other by an angular distance of 120 degrees. Each of the cam projections (21P) is configured to have a curved helical ramp sliding surfaces (24a, 24b) on its either sides and a curved surface (24c) on its center facing side. The height of the ramp sliding surfaces (24a, 24b) of the helical ramp may be same or may differ. The cam projections (21P) has an engagement depth “D” which is less than the depth “Dt” of the tabs (21VT) thus forming a step (21TS) thereby.

[0025] Further, referring to the Fig. 6a, the driving element (20) is configured to have a drive side curve radius (CMAR) and a coasting/kick side curve radius (CMKR). The the ramp surfaces (24a, 24b) of driving element (20) is configured to have a crown radius (CTMAR). The drive side curve radius (CMAR) increases the normal reaction or torque pressure at the plate stack (30) and crown radius (CTMAR) helps in establishing a contact patch of assist surface gets centralized which gives the better performance and better life of the torque transmission device.

[0026] The steel plates (30B) and the friction plates (30A) are alternatively arranged with each other to form the plate stack (30). The plate stack (30) of the friction plates (30A) and steel plates (30B) is mounted on the splines (20ST) of the splined portion (20SP) of the driving element (20).

[0027] Referring to Figs. 4, 5a and 5b, the driven element (40) is configured to have an annular disc portion (40D) and a base projection (40P) wherein the base projection (40P) is connected to the disc portion (40D) with the help of at least three cam portions (41) in an integral manner forming a unitary arrangement of the driven element (40). The base projection (40P) is configured to have a three-point fidget spinner shaped profiled claws (43) projecting from a main cylindrical body (40C). The cam portions (41) are configured to have an arcuate segment (41C) and a flat portion (41F) forming an L-shaped cross-sectional profile (L). The arcuate segment (41C) is connected to the inner circumferential edge of the rear face (40R) of the disc portion (40D) of the driving element (40) and the flat portion (41F) is connected to the cylindrical body (40C) of the base projection (40P). The flat portion (41F) of the cam portions (41) has a profile formed in a shape of sectorial pie wherein the said cam portions (41) projects away from the rear face (40R) of the disc portion (40D) of the driven element (40) thus forming a housing cavity (40RC) at the front side thereby. Further, each of the flat portion (41F) of the cam portion (41) is configured to have a thorough hole (41BH) wherein the said hole (41BH) facilitates the flow of the oil jet to the plate stack (30) of the torque transmission device (300).

[0028] The cylindrical body (40C) of the base projection (40P) is configured to have splines (40S) formed over its inner peripheral surface wherein the said splines (40S) engages with an input shaft of the transmission box (not shown). The claws (43) of the base projection (40P) are configured to mate with the guiding face (20G) of the tabs (21VT) of the driving element (20). These guiding claws (43) are used to maintain the concentricity and alignment of driving element (20) and the driven element (40) with respect to each other.

[0029] Each of the cam portions (41) has curved helical ramp sliding surfaces (44a, 44b) on its both sides. The cam portions (41) has an engagement depth “D” and the said cam portions (41) are formed in a manner to have equiangular spacing of 120° from each other thus forming a cavity (42) in between the said cam portions (41). The said cavities (42) are configured to receive the cam projections (21P) of the driving element (20). The flat base (41F) of the cam portions (41) of the driven element (40) is configured to have a circular cavity (44) formed in a direction of the housing cavity (40RC). The said cavity (44) is formed in a concentric manner to the hole (41BH) of the each of the projections (41) of the driven element (40), wherein the diameter of each cavity (44) is greater than the diameter of the hole (41BH) thus forming a spring seating surface for the springs (50). These cavities (44) may vary from three to eight and said cavities are spaced at an angular distance ranging from 45 to 120 degree. The most optimized arrangement is of at least three cavities (44) spaced apart by an angular distance of 120 degrees. Each of the circular cavities (44) is configured to accommodate and provide abutting space for one end of the retaining springs (50). Further, a pair of triangular profiled oil retention pockets (45) are provided on both sides of the cavities (44). The profile of the oil retention pockets (45) may be selected from circular, rectangular, hexagonal, polygonal, conical and like or the combination thereof. The oil retention cavities (45) serves as oil reservoir for retaining the oil during working of the torque transmission device (300).

[0030] Further, referring to the Fig. 6b, the driven element (40) is configured to have a drive side curve radius (CFAR) and a coasting/kick side curve radius (CFKR). The the ramp surfaces (44a, 44b) of driven element (40) is configured to have a crown radius (CTFAR). The drive side curve radius (CFAR) increases the normal reaction or torque pressure at the plate stack (30) and crown radius (CTFAR) helps in establishing a contact patch of assist surface gets centralized which gives the better performance and better life of the torque transmission device.

[0031] The anti-centrifugal plate (60) is a circular disc having a central opening (C) to receive a transmission shaft. The said plate has a plurality of holes (60H) formed in a manner to have an equiangular spacing of 120° to each other so as to match the angular orientation of the lugs (21L) of the driving element (20). The holes (60H) are configured to receive the fastening means (70) therein that engages with the threaded groove (21BT) of the lugs (21L) of the driving element (20) and said fastening means (70) are preferably selected from the bolts.

[0032] The clutch plate assembly (200) is formed by mounting the plate stack (30) on the splines (20ST) of the splined portion (20SP) of the driving element (20). The driven element (40) is positioned over the plate stack (30) in a manner such that the said plate stack (30) is sandwiched in between the driving element (20) and the driven element (40). In this condition, the cam projections (21P) of the driving element (20) are housed in the cavities (42) of driven element (40). The springs (50) are positioned in the cavities (44) of the driven element followed by fitting the anti-centrifugal plate (60) over the springs (50). The anti-centrifugal plate, sometime called as clutch holder, (60) is clamped by fastening the bolts (70) to the lugs (21L) of the driving element (20) thus forming the clutch plate assembly (200) thereby. The said clutch plate assembly (200) is positioned in the cavity (110C) of the housing (110) of the housing assembly (100) to form the torque transmission device (300).

[0033] This unique arrangement of the torque transmission device (300) having the uniquely profiled driving element (20) and the driven element (40) helps in increasing the normal reaction or torque pressure at the plate stack (30) by the virtue of the drive side curve radius (CMAR) of the driving element (20) and the drive side curve radius (CFAR) of the driven element (40) in the assist mode. This consequently increases the torque transmission capacity and factor of safety of the torque transmission device. The increase in normal reaction or torque pressure on account of ramps (24b, 44a) is directly proportional to engine speed. For a given factor of safety, the assist ramp (24b) of the driving element (20) helps to reduce the efforts by 15- 35 % on the torque transmission device lever mounted on the handle bar of a vehicle. The said drive side curve radius (CMAR and CFAR) is intelligently optimized in a manner to impart the desired normal reaction in accordance with the below mentioned relations:

CMAR / CFAR = P * D

where,
CMAR is the drive side curve radius of the driving element;
CFAR is the drive side curve radius of the driven element;
D is the depth of the cam projection (21P, 41);
P is the multiplication factor, wherein P = 422 to 1016.

[0034] Also, the said driving element (20) and the driven element (40) helps in establishing the assist load by the virtue of the coasting/kick side curve radius (CMKR) of the driving element (20) and the coasting/kick side curve radius (CFKR) of the driven element (40) in the coasting/kick mode, when the curved helical assist ramp (24a) of the driving element (20) slides over the curved helical ramp surface (44b) of the driven element (40). This helps in increasing the efficiency of the non-electrical engine starting mechanism (kick in 2-wheeler and cranking handle bar in a 3-whheeler rickshaw). For a given engine cranking/starting torque, the assist ramp (24a) of the moving hub (20) helps to reduce the effort required to be applied at the kick or lever to start the engine. The said coasting/kick side curve radius (CMKR / CFKR) is designed in a manner to impart the desired coasting in accordance with the below mentioned relations:
CMKR / CFKR = K * D
where,
CMKR is the coasting/kick side curve radius of the driving element;
CFKR is the coasting/kick side curve radius of the driven element;
D is the depth of the cam projection (21P, 41);
K is the multiplication factor, wherein, K = 422 to 816.

[0035] Further, the said driving element (20) and the driven element (40) are configured to maintain a functional gap (G) in between the cam projections (21P) of the driving element (20) and the cam portion (41) of the driven element (40). The said functional gap (G) is intelligently optimized to eliminate the wear of the helical ramp surfaces (24a, 24b) of the driving element (20) and ramp surfaces (44a, 44b) of the driven element (40). The said functional gap (G) is configured to maintain a relation with the disengagement stroke length of the clutch as given below:
G = C * S
where, G is the functional gap;
S is the maximum disengagement stroke length of the clutch;
C is the constant, wherein C = 3.5 to 7.0.

[0036] Further, the uniquely profile driving element (20) and the driven element (40) helps in achieving a centralized contact patch of assist surface imparting the better performance and better life of the torque transmission device by the virtue of the crown radius (CTMAR) of the driving element (20) and the crown radius (CTFAR) of the driven element (40). The said crown radius (CTMAR / CTFAR) is optimized in accordance with the disengagement stroke length of the clutch as given in the below mentioned relation.
CTMAR / CTFAR = Q * S
where, CTMAR is the crown radius of the driving element;
CTFAR is the crown radius of the driven element;
S is the maximum disengagement stroke length of the clutch;
Q is the multiplication factor, wherein Q = 643 to 725.

[0037] As far as the working of the present invention is concerned, when the torque transmission device (300) is in engaged condition, the curved helical ramp sliding surfaces (24b, 24a) of the driving element (20) meshes with the curved helical ramp sliding surfaces (44a, 44b) of the driven element (40). The wedge action of these helical ramp surfaces (24b & 44a and 24a & 44b) gradually generate assist load in both directions viz. driving side and kick / coasting side. During the torque transmission to the driven element (40), the anti-centrifugal plate (60) compresses the spring (50) in such a manner as to achieve the desired pressure on the plate stack (30) and subsequently, the torque is transferred from the driven element (40) to the input shaft of the gear box of the vehicle. This unique engagement of the helical ramp sliding surfaces of the driving element (20) and the driven element (40) leads to a drastic reduction in ramp engagement noise imparting smooth engagement of the torque transmission device.

[0038] When the torque interruption from engine to the gearbox is required, the user presses the clutch lever placed on the handlebar of the vehicle which in turn transmits the force to the anti-centrifugal plate (60). The force on the anti-centrifugal plate (60) is then transmitted to the driven element (40) with the help of the retention springs (50). The driven element (40) axially slides over the splines (21ST) of the driving element (20) as a result of which the interfacial pressure between the plate stack (30) is reduced and the torque transmission device (300) is disengaged.

[0039] This novel and inventive construction of driving element (20) and the driven element (40) of the torque transmission device (300) efficiently increases the torque transmission capacity and factor of safety of the torque transmission device (300). For a given factor of safety, the assist ramp (24b) of the driving element (20) helps to reduce the efforts by 15- 35 % on the torque transmission device lever mounted on the handle bar of a vehicle. The kick side curve radius (CMKR, CFKR) of the driving element (20) and the driven element (40) help in increasing the efficiency of the non-electrical engine starting mechanism (kick in 2-wheeler and handle lever in a 3-whheeler rickshaw). For a given engine cranking/starting torque, the assist ramp (24a) of the moving hub (20) helps to reduce the effort required to be applied at the kick or lever to start the engine.

[0040] The disclosed invention hence overcomes the limitations of the known solutions of existing torque transmission devices. The torque transmission device for a vehicle as described above is mounted on the engine output shaft/gearbox input shaft. A person skilled in the art can change its mounting position without carrying out any significant change to the features of the torque transmission device. Hence, such changes in position must not be viewed as taking the emerging variants/embodiments out of the scope of claims of the disclosed invention.

[0041] The torque transmission device of the present invention in accordance with the discussed embodiment provides the following technical advantages that contribute to the technical advancement of the torque transmission devices for two wheeled and three wheeled vehicles:
- The optimized design of the torque transmission device having a uniquely profiled driving element and a driven element of the present invention significantly reduces the handle lever effort of the actuation means.
- The optimized design of the torque transmission device having a uniquely profiled driving element and a driven element of the present invention significantly reduces the engine cranking efforts leading to comfort to the user.
- The unique structure of the driving element and the driven element of the torque transmission device reduces the plate stacks by 30 - 50%.
- The present invention easily facilitates the curved helical ramps to manufacture separately making it detachably attached to the driving element depending on the vehicle weight and performance specifications of different makes of the vehicles.
- The unique architecture of this torque transmission device enables it to use effectively and comfortably without any limitation where the diameter of the torque transmission device platform is less than 110 mm.
- The unique oil paths of the driving and driven elements of the present invention facilitate an efficient heat dissipation from torque transmission device.
- The present invention provides the compact design of torque transmission device with reduced weight resulting in cost reduction.
- It effectively leads to drastic reduction of judder/vibrations, engagement noise and drag leading to enhanced and effortless feel of gear shifting.
- This unique construction of the torque transmission device enhances of the life by almost 30 per cent.

[0042] The foregoing description of the specific embodiment of the invention will so fully reveal the general nature of the embodiments herein that others can, by applying current general 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.
,CLAIMS:We Claim

1. A torque transmission device (300) for a two and three wheeled vehicles comprising of a housing assembly (100) and a clutch plate assembly (200), said clutch plate assembly (200) having a driving element (20), a plate stack (30), a driven element (40), a plurality of retaining springs (50), an anti-centrifugal plate (60) and a plurality of fastening means (70)
wherein
- the driving element (20) is configured to have an annular disc portion (20D) and a cylindrical projection (20C) wherein said cylindrical projection (20C) is integral to the disc portion (20D) and projects away from a front face (20F) of the said disc portion (20D);
- said cylindrical projection (20C) is configured to have a set of splined portion (20SP) having a plurality of splines (21ST) formed at a regular interval on the outer peripheral surface of the said cylindrical projection (20C);
- the driven element (40) is configured to have an annular disc portion (40D) and a base projection (40P) wherein the base projection (40P) is connected to the disc portion (40D) with the help of at least three cam portions (41) in an integral manner forming a unitary arrangement of the driven element (40);
- said base projection (40P) is configured to have a three-point fidget spinner shaped profiled claws (43) projecting from a main cylindrical body (40C); and
- said driving element (20) and the driven element (40) are configured to maintain a functional gap (G) in between the cam projections (21P) of the driving element (20) and the cam portion (41) of the driven element (40).

2. The torque transmission device (300) as claimed in claim 1, wherein
- the splines (20ST) of driving element (20) is configured to receive the plate stack (30) of steel plates (30B) and friction plates (30A) facilitating the axial movement of said plate stack (30);
- the splined portion (20SP) is configured to have projection length (21AL) wherein the said projection length extension (21AL) facilitates the guiding of the plate stack (30) and prevent the fall out of the friction / steel plates (30A, 30B) off the driving element (20);
- the disc portion (20D) of the driving element (20) is configured to have a plurality of rectangular pockets (20P) formed at its rear face (20R) and said pockets (20P) are formed at an equiangular distance to each other;
- the disc portion (20D) has at least three V-profiled tabs (20VT) projecting from the inner circumferential edge of the rear face (20R) and towards the center of the said disc portion (20D); and
- said disc portion (20D) of the driving element (20) is configured to have at least three cylindrical lugs (21L) projecting out from the tabs (20VT) and orthogonally away from the front face (20F) of the said driving element (20).

3. The torque transmission device (300) as claimed in claim 2, wherein
- the pockets (20P) of the driving element (20) are configured to have a geometry selected from circular, triangular, square, trapezoidal, and combination of thereof;
- the V-profiled tabs (20VT) of the driving element (20) are formed at an angle of 120° from each other, and each of said tabs (20VT) has a circular arc segmented face (20G) wherein the said face (20G) is configured to prevent the misalignment of the driven element (40); and
- the lugs (21L) of the driving element (20) are positioned at an equal angular distance from each other, and each of the said lugs (21L) is configured to have a threaded profiled (21BT) bore on its top face (21T).

4. The torque transmission device (300) as claimed in claim 3, wherein
- the disc portion (20D) of the driving element (20) is configured to a have at least three V-profiled cam projections (21P) and each of the V-profiled cam projections (21P) projects out from the V-profiled tabs (21VT) and merges with the respective lug (21L) of the said driving element (20) form a stepped profile (SP) at the base of the said lug (21L) from the inner side;
- the said projections (21P) are formed in a manner such that the projections (21P) extends towards the centre of the driving element (20) from the inner circumferential edge of the cylindrical projection (20C) and the lugs (21L) are positioned at the centre of the said cam projections (21P);
- each of the cam projections (21P) of the driving element (20) is configured to have an oil pocket (21PT) wherein the said oil pocket (21PT) is a V-profiled trench formed at the outer peripheral surface of the cylindrical projection (20C); and
- said oil pockets (21PT) has tapered walls (21ST) forming a taper angle (a) with the vertical wherein the said taper angle (a) ranges from 30 degrees to 90 degrees.

5. The torque transmission device (300) as claimed in claim 4, wherein
- the cam projections (21P) are positioned around the inner circumferential edge of the cylindrical projection (20C) in such a way that they are equidistantly spaced apart from each other by an angular distance of 120 degrees;
- each of the cam projections (21P) is configured to have a curved helical ramp sliding surfaces (24a, 24b) on its either sides and a curved surface (24c) on its center facing side;
- the height of said ramp sliding surfaces (24a, 24b) of the helical ramp may be same or may differ; and
- said cam projections (21P) are configured to have an engagement depth “D” which is less than the depth “Dt” of the tabs (21VT) thus forming a step (21TS) thereby.

6. The torque transmission device (300) as claimed in claim 5, wherein
- the driving element (20) is configured to have a drive side curve radius (CMAR) and a coasting/kick side curve radius (CMKR);
- the ramp surfaces (24a, 24b) of driving element (20) is configured to have a crown radius (CTMAR); and
- said drive side curve radius (CMAR) is configured to increase the normal reaction or torque pressure at the plate stack (30), and said crown radius (CTMAR) is configured to establish a contact patch of assist surface gets centralized which gives the better performance and better life of the torque transmission device.

7. The torque transmission device (300) as claimed in claim 3, wherein
- the driven element (40) has cam portions (41) and said cam portions (41) are configured to have an arcuate segment (41C) and a flat portion (41F) forming an L-shaped cross-sectional profile (L);
- said arcuate segment (41C) is connected to the inner circumferential edge of the rear face (40R) of the disc portion (40D) of the driving element (40), and said flat portion (41F) is connected to the cylindrical body (40C) of the base projection (40P);
- said flat portion (41F) of the cam portions (41) has a profile formed in a shape of sectorial pie wherein the said cam portions (41) projects away from the rear face (40R) of the disc portion (40D) of the driven element (40) forming a housing cavity (40RC) at the front side thereby; and
- each of the flat portion (41F) of the cam portion (41) is configured to have a thorough hole (41BH) wherein the said hole (41BH) is configured to facilitate the flow of the oil jet to the plate stack (30) of the torque transmission device (300).

8. The torque transmission device (300) as claimed in claim 7, wherein
- the cylindrical body (40C) of the base projection (40P) of the driven element (40) is configured to have splines (40S) formed over its inner peripheral surface and said splines (40S) are configured to engage with an input shaft of the transmission box;
- the claws (43) of the base projection (40P) are configured to mate with the guiding face (20G) of the tabs (21VT) of the driving element (20); and
- said guiding claws (43) are configured to maintain the concentricity and alignment of driving element (20) and the driven element (40) with respect to each other.

9. The torque transmission device (300) as claimed in claim 8, wherein
- each of the cam portions (41) of driven element (40) has curved helical ramp sliding surfaces (44a, 44b) on its both sides;
- said cam portions (41) are configured to have an engagement depth “D” and the said cam portions (41) are formed in a manner to have equiangular spacing of 120° from each other forming a cavity (42) in between the said cam portions (41);
- said cavities (42) are configured to receive the cam projections (21P) of the driving element (20);
- the flat base (41F) of the cam portions (41) of the driven element (40) is configured to have a circular cavity (44) formed in a direction of the housing cavity (40RC); and
- said cavity (44) is formed in a concentric manner to the hole (41BH) of the each of the projections (41) of the driven element (40), wherein the diameter of each cavity (44) is greater than the diameter of the hole (41BH) thus forming a spring seating surface for the springs (50).

10. The torque transmission device (300) as claimed in claim 9, wherein
- the cavities (44) may vary from three to eight and said cavities are spaced at an angular distance ranging from 45 to 120 degree;
- the most optimized arrangement of said cavities (44) is of at least three cavities (44) spaced apart by an angular distance of 120 degrees;
- each of said circular cavities (44) is configured to accommodate and provide abutting space for one end of the retaining springs (50);
- a pair of triangular profiled oil retention pockets (45) are positioned on either sides of the cavities (44);
- said oil retention pockets (45) are configured to serve as oil reservoir for retaining the oil during working of the torque transmission device (300); and
- the profile of said oil retention pockets (45) is selected from circular, rectangular, hexagonal, polygonal, conical and like or the combination thereof.

11. The torque transmission device (300) as claimed in claim 10, wherein
- the driven element (40) is configured to have a drive side curve radius (CFAR) and a coasting/kick side curve radius (CFKR);
- the ramp surfaces (44a, 44b) of driven element (40) is configured to have a crown radius (CTFAR); and
- the drive side curve radius (CFAR) is configured to increase the normal reaction or torque pressure at the plate stack (30) and crown radius (CTFAR) is configured to establish a contact patch of assist surface gets centralized which gives the better performance and better life of the torque transmission device.

12. The torque transmission device (300) as claimed in any of the claims 6 and 11, wherein
- the drive side curve radius (CMAR and CFAR) of the driving element (20) and the driven element (40) are intelligently optimized to impart the desired normal reaction and ratio of the same is configured to maintain a specific relation with depth (D) of the cam projection (21P, 41) as CMAR / CFAR = P * D, wherein P is the multiplication factor and varies from 422 to 1016;
- the coasting/kick side curve radius (CMKR / CFKR) of the driving element (20) and the driven element (40) are intelligently optimized to impart the desired coasting and ratio of the same is configured to maintain a specific relation with depth of the cam projection (21P, 41) as CMKR / CFKR = K * D, wherein K is the multiplication factor and ranges from 422 to 816; and
- the crown radius (CTMAR / CTFAR) of the driving element (20) and the driven element (40) are intelligently optimized and ratio of the same is configured to maintain a specific relation with the disengagement stroke length (S) of the clutch as CTMAR / CTFAR = Q * S, wherein Q is the multiplication factor and varies from 643 to 725.

13. The torque transmission device (300) as claimed in claim 1, wherein
- the functional gap (G) is intelligently optimized and is configured to eliminate the wear of the helical ramp surfaces (24a, 24b) of the driving element (20) and ramp surfaces (44a, 44b) of the driven element (40); and
- said functional gap (G) is configured to maintain a relation with the disengagement stroke length (S) of the clutch as G = C * S, wherein C is the constant and varies from 3.5 to 7.0.

14. The torque transmission device (300) as claimed in claim 1, wherein
- the housing assembly (100) comprises of a primary gear (105), and a housing (110), and said housing (110) is configured to have a circumferential cylindrical body (110CP) protruding out from a flat surface (110F) of the housing (110) in its circumferential direction;
- said housing (110) is configured to have a cavity (110C) in front side (110FS) of the housing (110) and the circumferential cylindrical body (110CP) is configured to have a plurality of housing windows (115) for mounting of friction plates (30A) with matching outer projections (315) of the friction plates (30A);
- the primary gear (105) is fixed to the flat surface (110F) in a rear side (110R) of the housing (110) by a suitable fixing means; and said primary gear (105) of the housing (110) is configured to receive the torque from the crank shaft of an engine and transfers the torque to the housing (110) through a damping system.

15. The torque transmission device (300) as claimed in claim 13, wherein
- the driven element (40) is positioned over the plate stack (30) in a manner such that the said plate stack (30) is sandwiched in between the driving element (20) and the driven element (40);
- the cam projections (21P) of the driving element (20) are configured to house in the cavities (42) of driven element (40);
- the springs (50) are positioned in the cavities (44) of the driven element followed by fitting the anti-centrifugal plate (60) over the springs (50);
- said anti-centrifugal plate (60) is clamped by fastening the bolts (70) to the lugs (21L) of the driving element (20) thus forming the clutch plate assembly (200) thereby; and
- said clutch plate assembly (200) is positioned in the cavity (110C) of the housing (110) of the housing assembly (100) to form the torque transmission device (300).

16. The torque transmission device (300) as claimed in claim 13, wherein
- the plate stack (30), formed by alternatively positioning the friction plates (30A) and steel plates (30B), is mounted on the splines (20ST) of the splined portion (20SP) of the driving element (20);
- the anti-centrifugal plate (60) is a circular disc having a central opening (C) to receive a transmission shaft and is configured to have a plurality of holes (60H) formed in a manner to have an equiangular spacing of 120° to each other so as to match the angular orientation of the lugs (21L) of the driving element (20); and
- said holes (60H) are configured to receive the fastening means (70) therein that engages with the threaded groove (21BT) of the lugs (21L) of the driving element (20) and said fastening means (70) are preferably selected from the bolts.

Dated this 21st day of Nov. 2024

(Sahastrarashmi Pund)
Head – IPR
Endurance Technologies Ltd.

To,
The Controller of Patents,
The Patent Office, at Mumbai