FORM 2
THE PATENTS ACT, 1970 (39 of 1970) & THE PATENTS RULES, 2003
COMPLETE SPECIFICATION (See section 10, rule 13) 1. Title of the invention: AN ENCLOSURE TO BE EMBEDDED IN A TIRE
2. Applicant(s)
NAME NATIONALITY ADDRESS
CEAT LIMITED Indian RPG HOUSE, 463, Dr. Annie Besant
Road, Worli, Mumbai, Maharashtra -400 030, India
3. Preamble to the description
COMPLETE SPECIFICATION
The following specification particularly describes the invention and the manner in which it
is to be performed.

TECHNICAL FIELD
[0001] The present subject matter relates, in general, to an enclosure to be
embedded in a tire of a vehicle and, particularly but not exclusively, to an enclosure to be embedded in a tire of a vehicle for encasing various electronic devices measuring various tire parameters.
BACKGROUND
[0002] Vehicle behavior is directly influenced by tire characteristics. Generally,
electronic devices are incorporated in a tire of a vehicle for measuring various parameters of the tire. These parameters may include but not limited to tire pressure, tire positioning w.r.t longitudinal, radial and lateral (X, Y, Z axis) directions with the help of gyroscope sensor, internal temperature of the tire, internal humidity of the tire, angular acceleration and deceleration of the tire, load on the tire, speed of rotation of the tire, distance travelled by the tire, traction of the tire, various types of failure of the tire, and events, such as wear, breaking acceleration and deceleration etc., of the tire. Measurement of these parameters is critical to the performance of the vehicle, optimizing fuel efficiency or driver’s actions in certain situations. Accordingly, inaccurate measurement of these parameters may adversely affect the vehicle behavior.
BRIEF DESCRIPTION OF DRAWINGS
[0003] The detailed description is described with reference to the accompanying
figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the drawings to reference like features and components.
[0004] Fig. 1 illustrates an enclosure to be embedded in a tire of a vehicle, in
accordance with another implementation of the present subject matter.

[0005] Figs. 1a and 1b illustrate schematics of a housing portion and a cover
portion, respectively, of the enclosure to be embedded in the tire of the vehicle, in
accordance with an implementation of the present subject matter.
[0006] Fig. 2 illustrates top view of the housing portion of the enclosure, in
accordance with an embodiment of the present subject matter.
[0007] Fig. 3 illustrates three axis of acceleration acting on the tire and to be
detected by an electronic device installed in the enclosure embedded in the tire, in
accordance with another embodiment of the present subject matter.
[0008] Fig. 4 illustrates acceleration profile for a single rotation of the tire, in
accordance with an implementation of the present subject matter.
DETAILED DESCRIPTION
[0009] The present subject matter relates to aspects relating to managing proper
orientation of electronic devices incorporated in a tire for measuring various tire parameters by providing an enclosure to be embedded in a tire for encasing the electronic devices.
[0010] For an electronic device installed in a tire to accurately measure a
parameter associated with the tire, the orientation of the electronic device needs to be aligned with the axis of the tire. Thus, the orientation of the electronic device is of critical importance. For example, sensitivity of accelerometer and gyroscope with respect to the movement of their position is high. A 180-degree shift in the electronic device (upside down placement) can cause a significant deviation in the measurements of these electronic devices. Mis-orientation of the accelerometer and gyroscope due to the wrong placement of these electronic devices can disrupt all measurement references.
[0011] Further, movement of tires may lead to change in orientation of the
electronic devices which results in deviation in the measurements performed by the electronic devices which in turn leads to an inefficient vehicle performance. Errors in the measurements of various tire parameters performed using the electronic devices

installed in the tire, need to be minimized for optimized performance of a vehicle and therefore, maintaining the orientation of the electronic devices is a primary consideration in an installation process where these electronic devices are installed in the tire.
[0012] In conventional designs, generally recesses are provided within the tire to
snap fit the electronic device in appropriate orientation. However, this design requires recesses to be formed in the tire and thus, cannot be suited to all tires or all electronic devices. Also, skilled labor is required for the fitment of the electronic device within the tire. In other designs, either some clips or hooks and other additional components are required to provide a snap fit of the electronic device within the tire. Although, these conventional designs may provide snap fit of the electronic device in a particular orientation, these designs are still susceptible to the risk of change in orientation of the electronic device because of dynamic movement and flexible nature of the tire.
[0013] An enclosure to be embedded in a tire of a vehicle for encasing various
electronic devices and ensuring proper orientation of these electronic devices within the tire is described in the present subject matter. In an embodiment, the enclosure overcomes the above-described problems associated with the conventional designs available for incorporating electronic devices in tires of vehicles.
[0014] In accordance with an embodiment of the present subject matter, an
enclosure to be embedded in a tire of a vehicle may include a housing portion and a cover portion. The housing portion comprising a base and side walls along periphery of the base while the cover portion comprises a flat surface. The housing portion includes a plurality of grooves formed in side walls and the cover portion includes a plurality of protrusions provided at periphery of the flat surface. The plurality of grooves in the side walls of the housing portion are provided to accommodate the plurality of protrusions of the cover portion to removably attach the cover portion to the housing portion. The plurality of grooves has a poka-yoke arrangement for the

insertion of a protrusion form amongst the plurality of protrusions in a corresponding
groove from amongst the plurality of grooves. Further, the poka-yoke arrangement is
implemented by varying a size of at least one groove and at least one protrusion from
amongst the plurality of grooves and the plurality of protrusions, respectively.
[0015] In an exemplary embodiment of the present subject matter, one or more
electronic devices may be mounted on the flat surface of the cover portion. The positioning and different sizes of the protrusions at the flat surface of the cover portion and the corresponding grooves in the sidewalls of the housing portion are such that protrusions can be accommodated only in their corresponding grooves providing a poka-yoke arrangement. This arrangement ensures that the electronic devices mounted on the cover portion of the enclosure are installed in the enclosure only in a predefined orientation. Accordingly, the design of the enclosure is such that it facilitates the orientation of the electronic device in-line with the axis of the tire, which in turn facilitates the accuracy and/or sensitivity of the results of the electronic device.
[0016] Further, the enclosure also ensures that the orientation of the electronic
devices do not change during motion of the tires. In an example implementation, the housing portion is fixedly attached to the tire while the engagement of the grooves and protrusions secures the cover portion to the housing portion to avoid change in positioning of the enclosure and in turn the electronic devices due to any movement that the tire may undergo.
[0017] The above and other features, aspects, and advantages of the subject matter will be better explained with regard to the following description and accompanying figures. It should be noted that the description and figures merely illustrate the principles of the present subject matter along with examples described herein and, should not be construed as a limitation to the present subject matter. It is thus understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure.

Moreover, all statements herein reciting principles, aspects, and examples thereof, are intended to encompass equivalents thereof. Further, for the sake of simplicity, and without limitation, the same numbers are used throughout the drawings to reference like features and components.
[0018] Fig. 1 illustrates an enclosure 100 to be embedded in a tire (not shown) of
a vehicle (not shown), in accordance with another implementation of the present subject matter. While Figs. 1a and 1b illustrate schematics of a housing portion 101 and a cover portion 102, respectively, of the enclosure 100, in accordance with an implementation of the present subject matter. For sake of ease of explanation, Figs. 1, 1a and 1b are explained together.
[0019] The enclosure 100 to be embedded in the tire of the vehicle, in an
implementation of the present subject matter, comprises a housing portion 101 and a cover portion 102. The housing portion 101 may comprise a base 103 and side walls 104 along the periphery of the base 103. Plurality of grooves 105 are provided in the side walls 104. The cover portion 102 has a flat surface 109 and plurality of protrusions 110 are provided at the periphery of the flat surface 109. The plurality of grooves 105 in the side walls 104 of the housing portion 101 are provided to accommodate the plurality of protrusions 110 of the cover portion 102 to removably attach the cover portion 102 to the housing portion 101.
[0020] A poka-yoke arrangement is provided for the insertion of a protrusion
from amongst the plurality of protrusions 110 in a corresponding groove from amongst the plurality of grooves 105. The poka-yoke arrangement is implemented by varying a size of at least one of the grooves 105-1 and at least one of the protrusions 110-1 from amongst the plurality of grooves 105 and the plurality of protrusions 110 respectively. The poka-yoke arrangement ensures that each of the plurality of protrusions 110 is coupled to the corresponding groove 105 of same size only, when the cover portion 102 is removably attached to the housing portion 101.

[0021] In an exemplary implementation, three grooves 105 (105-1, 105-2, 105-3)
may be provided in the side walls 104 of the base 103 of the housing portion 101 and three corresponding protrusions 110 (110-1, 110-2, 110-3) may be provided at the periphery of the flat surface 109 of the cover portion 102 as illustrated in Fig. 1a and Fig. 1b, respectively. Further, the poka-yoke arrangement can be implemented by providing the size of one of the three grooves 105-1 and one of the three protrusions 110-1 larger than the size of other grooves 105-2, 105-3 and other protrusions 110-3, 110-3.
[0022] In an embodiment of the present invention, one or more electronic
devices 112 may be mounted on the flat surface 109 of the cover portion 102 of the enclosure 100. The cover portion 102 may also comprise one or more batteries 113 mounted on its flat surface 109 to serve as a power source for the one or more electronic devices 112 mounted thereon. Easy engagement/disengagement of the protrusions 110 on the cover portion 102 with/from the grooves 105 in the housing portion 101 facilitates serviceability of the electronic devices 112 mounted on the cover portion 102. This also makes the batteries 113 mounted on the cover portion 102 easily replaceable.
[0023] In an implementation of the present subject matter, the housing portion
101 is attached to a center of a tire. Attachment of the housing portion 101 to the center of the tire in turn leads to an attachment of the cover portion 102 to the center of the tire because of the poka-yoke arrangement and consequently facilitates alignment of the electronic devices 112 mounted on the cover portion 102 to the center of the tire. The alignment of the electronic devices 112 at the center of the tire is needed as maximum contact length of the tire with the ground is detected through the electronic devices 112 like accelerometer, when such electronic devices 112 are aligned exactly at the center of the tire or close to the center of the tire. This in turn improves the accuracy of the results of the electronic devices 112.

[0024] In an example implementation, the housing portion 101 may be provided
with orientation guidance markings to enable attachment of the housing portion 101 to the tire at the center of the tire. Accordingly, in one embodiment, the base 103 of the housing portion 101 extends beyond the periphery of the base 103 where the side walls 104 are located. The extended portion 107 of the base 103 comprises orientation guidance markings to enable attachment of the housing portion 101 to the tire at the center of the tire
[0025] In an example, the extended portion 107 comprises a pair of projections
108 located at a peripheral edge of the extended portion 107. This pair of projections 108 serves as orientation guidance markings to enable attachment of the housing portion 101 to the tire at the center of the tire. In another example, orientation guidance markings may be arrow heads or dots engraved or any similar identifier engraved, embossed or otherwise created on the extended portion 107 of the base 103 of the housing portion 101 at the position corresponding to the pair of projections 108. In yet another example, it is also possible to have orientation guidance markings painted on the extended portion 107 of the base 103.
[0026] Further example embodiments, where the orientation guidance markings
are provided on the base 103 of the housing portion 101 as opposed to the extended portion 107 of the base 103, are also possible. For instance, orientation guidance markings, in the form of a pair of, say red dots, may be painted on the base 103. As will be understood, a position of such orientation guidance markings provided at the base 103 corresponds to the position of the pair of projections 108 provided on the extended portion 107 of the base 103 as shown in the Fig. 1a.
[0027] While attaching the housing portion 101 on the tire, the pair of
projections 108 enable alignment of center of the housing portion 101 with the center of the tire. In an example embodiment, the center of the tire can be indicated through a marking specified along a centerline of the tire which is situated at a midpoint across the width of the tire. In an example, these markings can be specified in the

form of dotted or solid colored lines painted along the centerline of the tire. In another example, these markings may be dots or any similar identifier engraved, embossed or otherwise created on the centerline of the tire. The orientation guidance markings on the extended portion 107 of the base 103 of the housing portion 101 are aligned with the marking specified at the centerline of the tire, when the housing portion 101 or the enclosure 100 is attached to the tire. Thus, once housing portion 101 of the enclosure 100 is aligned with the center of the tire, a predefined alignment of the cover portion 102 and in turn that of the electronic devices 112 mounted on the cover portion 102 is also achieved owing to the poka-yoke arrangement for attachment of the cover portion 102 with the housing portion 101.
[0028] Fig. 2 shows the top view of the housing portion 101 illustrating angular
displacement of the plurality of grooves 105 formed in the sidewalls 104 of the
housing portion 101 with each other and with respect to the pair of projections 108.
In an example, the plurality of grooves may be located at an angular displacement of
120 degree. In another exemplary implementation, the dimension of the enclosure
100 (indicated as m in Fig. 2) including the diameter of the housing portion 101 and
length of the pair of projections 108, if these projections are provided as orientation
guidance markings on the extended portion 107 of the base 103, may be 85.4±0.2.
Further, the diameter of the cover portion (indicated as n in Fig. 2) may be 59.5±0.2.
[0029] In an embodiment, the housing portion 101 can be fixedly attached to the
tire using an adhesive. In other embodiments, the housing portion 101 can be fixedly attached to the tire by providing cavity inside the tire and inserting the enclosure in the cavity.
[0030] In an example embodiment, reinforcing ribs 106 are provided vertically
on the side walls 104 of the housing portion 102. These reinforcing ribs provide strength to the enclosure.
[0031] The cover portion 102 comprising the one or more electronic devices 112
is removably inserted to the housing portion 101 of the enclosure 100 in such a way

that each protrusion 110 on the cover portion 102 is engaged in the corresponding groove 105 of the equivalent size. With such poka-yoke arrangement, the electronic devices 112 mounted on the cover portion 102 are installed in the tire only in a predefined orientation, which enables the alignment of the electronic devices 112 in line with the axis of the tire. Thus, x, y and z- axis of the electronic device 112 are aligned with the corresponding x, y and z- axis (tangential, lateral and radial directions respectively) of the tire for accurate and reliable measurement of tire parameters measured by the respective electronic device 112. For example, a three axis accelerometer is mounted on the flat surface 109 of the cover portion 102 as an electronic device 112 for three axis measurement of the acceleration, with the x-axis measuring the tangential, y-axis measuring the lateral and z-axis measuring the radial acceleration of tire. In this case, since the accuracy of the measured tangential, lateral and radial acceleration of the tire highly depends on the alignment of coordinates of the electronic devices 112 with that of the tire, any misalignment of the axis of the electronic device 112 with that of the tire may lead to incorrect results. The misalignment of the electronic device 112 with that of the tire may happen due to movement and flexible nature of the tire and attachment of the electronic device 112 to the tire in an incorrect orientation. This problem of inaccurate measurement of tire parameter, such as acceleration due to the misalignment of the electronic device 112 with that of the tire is addressed through the herein-explained design of the enclosure 100 to be embedded in the tire for encasing the electronic devices 112. The orientation guidance markings provided on the extended portion 107 of the base 103 of the housing portion 101 of the enclosure 100 ensures that the housing portion 101 is attached to the center of the tire in the predefined orientation to further facilitate the attachment of the cover portion 102 comprising the electronic devices 112 in the same orientation. Further the poka-yoke arrangement ensures that the coordinates of the electronic device 112 mounted on the cover portion 102 of the enclosure 100 is aligned exactly with the axis of the tire, when cover portion 102 is attached to the

housing portion 101. The poka-yoke arrangement also ensures that the alignment of
the electronic devices 112 is maintained during the movement of the tire. As no
misalignment of the electronic devices 112 with that of the tire happens, the errors in
the measurements performed through these electronic devices 112 are minimized.
[0032] Fig. 3 illustrates the three axis of acceleration acting on the tire that may
need to be detected by the electronic device 112 installed in the enclosure 100 embedded in the tire. The components At, Ar, Ac, a and g represents Tangential Acceleration, Radial Acceleration, Centrifugal Acceleration, Tire Forward Acceleration and, Gravity respectively. Angle between the components of gravity and tangential acceleration is represented through θ.
[0033] Fig. 4 illustrates acceleration profile for single rotation of the tire. The
importance of the orientation can be evident through the profile of the various acceleration forces, for example, tangential and radial acceleration components (indicated in Fig. 3), with respect to the tire as shown in Fig. 4. A tire in motion in free space at a constant speed is a body in constant acceleration. However, a tire in motion on the road at a constant speed experiences constant acceleration except when the tire comes in contact with the road. Referring to Fig. 4, the enclosure 100 comprising the electronic devices 112 is placed in a tire at one specific position. When this portion of the tire comes in contact with the road (as specified through the lines S1 and S2 in Fig. 4), there are three major events that take place: (1). The tire experiences a sudden impact at the point of touching the road (with reference to the electronic devices). This is explained by the sudden jump in acceleration upwards. (2) The tire experiences a sudden deceleration as it passes through the contact portion of the road. This is explained by the rapid downward acceleration profile that looks like a braking event. This is due to the resistance of the tire caused by the traction. (3) The tire once again experiences a sudden acceleration as it leaves the road (with reference to the electronic devices). This is explained by the sudden jump

in acceleration upwards once again. Once the tire leaves the contact patch, it experiences acceleration of a free body in circular motion.
[0034] In an embodiment, the base 103 of the housing portion 101 can be
hollow. The hollow base of the housing portion 101 reduces the weight of the enclosure 100 and also does not create additional heat and pressure which can otherwise let the cover portion 102 and correspondingly the electronic devices 112 to pop out from the enclosure 112. Thus, it helps to maintain the pressure equilibrium and prevent heat built up within the enclosure 100, which prevent the cover portion 102 and consequently the electronic devices 112 to pop out from the housing portion 101.
[0035] In another embodiment, the enclosure 100 may be made up of rubber. A
common rubber, for example, butyl rubber may be used for making an enclosure 100 to be embedded in all types of tires. Alternatively, the enclosure 100 may be made up of the same material as that of the tire. Hence, there is no requirement of introducing any foreign material (plastic or like substrates) within the tire. Other alternative materials that can be used for this purpose include but not limited to Bromobutyl Rubber- 80-100, Natural Rubber- 0-20, Tackifier- 6-8, Carbon Black- 65-75, Zinc Oxide- 2-4, Stearic Acid- 1-2, Stearic Acid- 1-2, Accelerator MBTS- 1-2, MGO- 0-0.5, SULPHUR- 0-0.75 (All ingredients are in parts per hundred of rubber (PHR)). Manufacturing enclosure 100 with the rubber or the like material aids in easy installation of the enclosure 100 within the tire. This also aids in easy insertion/removal of the cover portion 102 of the enclosure 100 in/from the housing portion 101 which is fixedly attached to the tire. This in turn facilitates the easy serviceability of the one or more electronic devices 112 and easy replaceability of the one or more batteries 113 mounted on the cover portion 102. Further, use of the rubber in making of the enclosure also avoids the possibility of popping the cover portion and correspondingly the electronic devices mounted thereon out of the

housing portion because of the dynamic movement and flexible nature of the tire. As
will be understood, popping out of the cover portion may happened in case of use of
plastic and similar material in the making of enclosure. This is because inflexible
nature of plastic and similar material may make the enclosure non-compliant with
forces that may act upon the enclosure due to dynamic movement of the tire.
[0036] Although implementations for an enclosure 100 to be embedder in a tire
are described, it is to be understood that the present subject matter is not necessarily limited to the specific features of the systems described herein. Rather, the specific features are disclosed as implementations for the enclosure 100 to be embedded in a tire.

I/ We claim:
1. An enclosure 100 to be embedded in a tire of a vehicle, the enclosure 100
comprising:
a housing portion 101 comprising a base 103 and side walls 104 along periphery of the base 103, the side walls 104 having a plurality of grooves 105; and
a cover portion 102 having a flat surface 109 with plurality of protrusions 110 provided at periphery of the flat surface 109, wherein
the plurality of grooves 105 in the side walls 104 is to accommodate the plurality of protrusions 110 to removably attach the cover portion 102 to the housing portion 101, and wherein
the plurality of grooves 105 has a poka-yoke arrangement for insertion of a protrusion from amongst the plurality of protrusions 110 in a corresponding groove from amongst the plurality of grooves 105, the poka-yoke arrangement being implemented by varying a size of at least one groove 105-1 and at least one protrusion 110-1 from amongst the plurality of grooves 105 and the plurality of protrusions 110, respectively.
2. The enclosure 100 as claimed in claim 1, wherein the housing portion 101 is attached to a center of the tire.
3. The enclosure 100 as claimed in claim 2, wherein the base 103 comprises an extended portion 107 beyond the periphery of the base 103 where the side walls 104 are located.
4. The enclosure as claimed in claim 3, wherein the extended portion 107 comprises orientation guidance markings to enable attachment of the housing portion 101 to the tire at the center of the tire.

5. The enclosure 100 as claimed in claim 4, wherein the orientation guidance markings are a pair of projections 108 located at a peripheral edge of the extended portion 107.
6. The enclosure 100 as claimed in claim 1, wherein the housing portion 101 is fixedly attached to the tire using an adhesive.
7. The enclosure 100 as claimed in claim 1, wherein the cover portion 102 comprises one or more electronic devices 112 mounted on the flat surface 109 of the cover portion 102.
8. The enclosure 100 as claimed in claim 1, wherein reinforcing ribs 106 are provided vertically on the side walls 104 of the housing portion 102.
9. The enclosure 100 as claimed in any one of the claims 1 to 8, wherein the enclosure 100 is made up of the rubber.
10. The enclosure 100 as claimed in any one of the claims 1 to 9, wherein the enclosure 100 is made up of the same material as that of the tire.
11. The enclosure 100 as claimed in any one of the claims 1to 10, wherein the side walls 104 comprise three grooves 105 and the cover portion 102 comprises three protrusions 110 located at the periphery of the flat surface 109, and wherein the poka-yoke arrangement is implemented by providing the size of one of the three grooves 105-1 and one of the three protrusions 110-1 larger than the size of other grooves 105-2, 105-3 and other protrusions 110-2, 110-3.