[1 ] The present subject matter described herein generally relates to a motorcycle or a saddle -type vehicle and particularly but not exclusively relates to a frame structure for said motorcycle or saddle-type vehicle.

Background

[2] Contemporary motorcycles are seeing the use of a plurality of electronic devices. Said electronic devices are used for a number of vehicle related control operations. Typically, in order to ensure reliable mounting of said electronic devices, they are secured to a portion of a frame structure of a motorcycle. It is particularly important to ensure reliable mounting of said electronic devices which are typically connected to wiring harnesses, as even a slight damage to either the electronic device or to the wiring harness could result in a serious accident including a fire accident. Moreover, there is also a need to ensure that there is no change in the orientation of the electronic device due to vehicle vibrations. Change in orientation typically leads to loosening of fasteners used to secure the electronic devices, further leading to detachment of the electronic device. Further, change in orientation of the electronic device due to rotation about a point of mounting, causes the electronic device to foul with neighbouring vehicle parts leading to collateral damage. There is therefore a need to ensure reliable mounting of electronic devices in the motorcycle, while ensuring ease of assembly and serviceability of the electronic device. Further, there is also a need to ensure that l while the electronic device is being secured to a portion of the frame structure; significant modifications are not made to the frame structure so that commonality in frame structure can be maintained across a few motorcycle segments, even while making minor changes to the electronic devices.

Summary of the Invention

[3] The present invention has been made in view of the above circumstances.

[4] It is an object of the present invention to provide a frame structure for a motorcycle, said frame structure adapted to support an electronic unit including an electrical coil connected thereto.

[5] It is another object of the present invention to provide a frame structure for a motorcycle, said frame structure including a primary support member which is configured to restrict rotation of an electronic unit about a portion of said frame structure.

[6] It is yet another object of the present invention to provide a frame structure for a motorcycle, said frame structure including a primary support member which does not rotate about a portion of said frame structure.

[7] It is still another object of the present invention to provide a frame structure for a motorcycle, said frame structure including a primary support member which can be easily secured to said frame structure without significant modifications to said frame structure. [8] It is one more object of the present invention to provide a frame structure for a motorcycle, said frame structure including a primary support member to enable retro-fitability of an electronic unit to a frame structure of any existing motorcycle.

[9] It is one more object of the present invention to provide a frame structure for a motorcycle, said frame structure including a primary support member which enables ease of assembly of an electronic unit to a portion of said frame structure.

[10] It is still another object of the present invention to provide a frame structure for a motorcycle, said frame structure including a primary support member which facilitates convenient servicing of an electronic unit.

[11 ] Accordingly, the above and other objects are achieved by providing a frame structure for a motorcycle, as per embodiments detailed in the description provided. The frame structure as per the present invention includes a head tube, a down frame member extending downwards and rearwards from said head tube towards a first engine mounting bracket, a main frame member extending rearwards from said head tube and further extending downwards towards a second engine mounting bracket, and a bridge frame member supported between at least a portion of said down frame member and at least a portion of said main frame member. Particularly, said bridge frame member is disposed above a cylinder head of an internal combustion engine supported by said first engine mounting bracket and said second engine mounting bracket.

[12] As per an aspect of the present invention, said frame structure serves to support an electronic unit. Particularly, said frame structure is adapted to support said electronic unit reliably, particularly by ensuring that there is no change in orientation of said electronic device. As per one embodiment, said bridge frame member is provided with a primary support member for holding said electronic unit. In an implementation, said primary support member is detachably attached to said bridge frame member through a secondary support member. In another implementation, said primary support member is directly rigidly attached to a portion of said frame structure.

[13] As per an embodiment, said primary support member is an elongated bracket including a mounting boss protruding from a surface thereof for receiving said electronic unit removably. In an embodiment, said electronic unit includes an electrical coil. Said mounting boss is flanked from at least two sides by an L shaped flange formed integrally at one end of said primary support member which serves to restrict rotation of said electronic unit about said mounting boss. As a result, damage of said electronic unit due to fouling of said electronic unit with neighbouring parts is prevented.

[14] As per one more aspect of the present invention, the primary support member is provided with a support pip extending from one end thereof which clings to said secondary support member in its assembled condition, thereby preventing rotation of said primary support member about said secondary support member. In an embodiment where said primary support member is directly supported against a portion of said frame structure, said support pip aids in preventing rotation of said primary support member about said portion of said frame structure.

[15] Thus, the structure and construction of the primary support member as per the present invention not only serves to restrict rotation of said electronic unit about said mounting boss provided therein, but also serves to restrict rotation of the primary support member itself about a portion of the frame structure.

[16] In an embodiment, said electronic unit is an ignition control unit. Said ignition control unit is operably connected to a spark plug of the internal combustion engine and serves to improve efficiency of combustion by providing long spark duration along with better spark energy.

[17] Summary provided above explains the basic features of the invention and does not limit the scope of the invention. The nature and further characteristic features of the present invention will be made clearer from the following descriptions made with reference to the accompanying drawings.

Brief Description of Drawings

[18] The above and other features, aspects, and advantages of the subject matter will be better understood with regard to the following description and accompanying drawings where:

[19] FIG.l illustrates a side view of a motorcycle including a frame structure in accordance with an embodiment of the present invention.

[20] FIG.2 illustrates a detailed right side view of a portion of said frame structure depicting an electronic unit as mounted to said frame structure in accordance with an embodiment of the present invention.

[21 ] FIG.3 illustrates an exploded view depicting mounting of said electronic unit through a primary support member to a portion of said frame structure in accordance with an embodiment of the present invention.

5 [22] FIG.4 illustrates a perspective view of said primary support member in accordance with an embodiment of the present invention.

Detailed Description

[23] Exemplary embodiments detailing features of the frame structure, in accordance with the present invention will be described hereunder with reference to the accompanying drawings. Various aspects of different embodiments of the present invention will become discernible from the following description set out hereunder. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Further, it is to be noted that terms D upperD , D lowerD , D rightD , D leftO , D frontD , D forwardD , D rearwardD , D downwardD , D upwardD , D topD , D bottomD and like terms are used herein based on the illustrated state or in a standing state of the motorcycle with a driver riding thereon. Furthermore, a motorcycle longitudinal axis refers to a front to rear axis relative to the motorcycle, while a motorcycle lateral axis refers to a side to side, or left to right axis relative to the motorcycle. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

[24] FIG.l illustrates a side view of motorcycle 10 in accordance with the present invention. The motorcycle 10 includes a frame structure 20 to support different parts of said motorcycle 10. The frame structure 20 includes a head tube 21 at its front end. The head tube 21 supports a steering shaft (not shown) rotatably in a certain range. In an upper portion of the head tube 21, a handlebar 15 is

6 rotatably integrally connected to the steering shaft. The handlebar 15 is used to steer the motorcycle 10 and is connected to a front wheel 17 through the steering shaft and a front fork assembly 16. An upper portion of the front wheel 17 is covered by a front fender 18 which prevents mud and water from getting deflected towards the steering shaft. Further, the front fork assembly 16 is supported on the front fender 18 by means of a brace fender (not shown).

[25] In a front portion of the frame structure 20, a fuel tank 40 is arranged immediately behind the handlebar 15 and is disposed over an internal combustion engine 45, hereinafter DengineD. A seat 50 is placed behind the fuel tank 40. The seat 50 includes a front rider portion and rear pillion portion.

[26] For the safety of the rider and in conformance with the traffic rules, a headlamp unit 55 and a turn signal lamp unit 56 are provided in the front portion of the motorcycle 10. The headlamp unit 55 and the turn signal lamp unit 56 are housed in a front cowl assembly 57, which includes a front housing cover and a rear housing cover coupled to each other through a housing stay.

[27] Suspension systems are provided for comfortable steering of the motorcycle 10 on the road. The front fork assembly 16, which forms the front suspension system, serves as rigidity component just like the body frame. The front fork assembly 16 clamped to the head tube 21 through an upper bracket 21a and a lower bracket 21b is capable of being moved to the left and right. Further, a rear suspension system, which is a hydraulic damped arrangement, is connected to the body frame 20. The rear suspension system comprises of at least one rear suspension 60 preferably on a left hand side of the motorcycle 10. However, in a motorcycle with two rear suspensions, the same may be disposed on the left side and the right side respectively of said motorcycle.

[28] The engine 45 is mounted to a front lower portion of the frame structure 20 by means of two or more engine mounting brackets. The engine 45 is equipped with an exhaust system that includes an exhaust pipe (not shown) connected to the engine 45 and a muffler (not shown) connected to the exhaust pipe. The muffler (not shown) extends rearwards along the right side of the rear wheel 61.

[29] Further, a swing arm (not shown) extending rearwards is swingably connected to a lower rear portion of the frame structure 20. The rear wheel 61 is rotatably supported at a rear end of the swing arm (not shown). Power from the engine 45 is transmitted to the rear wheel 61 through a power drive mechanism, such as a drive chain, so as to drive and rotate the rear wheel 61.

[30] A rear fender 66 for covering an upper side of the rear wheel 61 is mounted to a rear portion of frame structure 20 to prevent mud and water splashed by the rotating rear wheel 61 from entering the muffler, the engine 45 and other parts disposed close by.

[31 ] To enhance the overall aesthetics of the motorcycle 10 and to prevent undesired foreign particles from entering parts of the motorcycle, a plurality of rear covers 70 is attached to a rear portion of the frame structure 20.

[32] FIG.2 illustrates a detailed view of a front portion of said frame structure 20 in accordance with an embodiment of the present invention. As may be seen said frame structure 20 comprises said head tube 21 at its foremost end, a down frame member 22 extending downwards and rearwards from said head tube 21 towards a first engine mounting bracket 21a secured to a lower end of said down frame member 22, a main frame member 23 extending rearwards and partially downwards towards a second engine mounting bracket 23a secured to a lower portion of said main frame member 23, a pair of seat rail members 24 extending rearwardly from an intermediate portion of said main frame member 23 for supporting the seat 50, and a pair of side frame members 25 extending inclinedly forwardly and downwardly towards said second engine mounting bracket 23a from a portion of said pair of seat rail members 24. Further, the frame structure 20 also includes a bridge frame member 26 supported between at least a portion of said main frame member 23 and at least a portion of said down frame member 22. The member 26 is disposed substantially downstream to the head tube 21 as well as downstream to a downtube of the frame structure 20. Also the member 26 is disposed downstream of the main tube frame structure 23 and substantially above the engine 45 and the power drive mechanism.

[33] As per an embodiment of the present invention, the engine 45 is disposed in a space formed between said main frame member 23 and said down frame member 22 by being supported by the first engine mounting bracket 21a and the second engine mounting bracket 23a. Particularly, the engine 45 is disposed in a manner so that a cylinder head 45a of the engine lies below said bridge frame member 26. As per an aspect of the present invention, said bridge frame member 26 serves to support an electronic unit 30 including an electrical coil 30a. In the present embodiment, said electronic unit 30 is an ignition control unit including an electrical coil being operably connected to a spark plug 46 of the engine 45. Said ignition control unit serves to provide long spark duration along with better spark energy for causing better combustion of air fuel mixture in the engine 45. However, in another embodiment said electronic unit 30 may constitute an electronic unit for performing other vehicle controls including battery control, lighting control, vehicle display control and the like. To enable optimum functioning, ease of assembly, service, good thermal effectiveness, high stiffness and low harness cost, the electronic unit 30 is disposed substantially on the downstream side of the said bridge frame member 26 and overlaps with a cylinder head unit of the engine 45 when seen in a side view of the motorcycle 10.

[34] FIG.3 illustrates an exploded view depicting mounting of said electronic unit 30 in accordance with an embodiment of the present invention. As per an aspect of the present invention, said electronic unit 30 is secured to said bridge frame member 26 through a primary support member 27. In an implementation said primary support member 27 is secured to said bridge frame member 26 through a secondary support member 28. However, in another implementation, said primary support member 27 can be directly rigidly secured to said bridge frame member 26. In the present embodiment, firstly said primary support member 27 is detachably attached to said secondary support member 28 followed by detachable attachment of said electronic unit 30 to said primary support member 27.

[35] FIG.4 illustrates a perspective view of said primary support member 27 in accordance with an embodiment of the present invention. The primary support member 27 as per the present invention is an elongated bracket having a mounting boss 27a protruding forwardly from a surface thereof. Said mounting boss 27a serves to removably receive said electronic unit 30 (shown in FIG.3). Particularly, in the present embodiment said mounting boss 27a is rigidly attached to one mounting hole of one or more mounting holes 27m. However, in another embodiment, said mounting boss 27a may be integrally formed with said primary support member 27. As may be seen in FIG.3 a fastener is used to detachably attach said electronic unit 30 to said mounting boss 27a. The mounting boss 27a includes a central threaded hole 27aa to receive said fastener. Further, said mounting boss 27a includes a front collar 27ab having a diameter greater than that of diameter of a rear end 27ac of said mounting boss 27a. Providing a larger diameter for the front collar 27ab aids in ensuring that a rear surface of the electronic unit 30 rests against said front collar 27ab when said electronic unit 30 is attached to said mounting boss 27a. Further, providing a smaller diameter for said rear end 27ac of the mounting boss 27a facilitates easy access of a tool used for rigidly securing said mounting boss 27a to the surface of the primary support member 27 or to said one mounting hole of said one or more mounting holes 27m. In the present embodiment, said one or more mounting holes 27m includes a first mounting hole 27ma at an upper portion and a second mounting hole 27mb at a lower portion respectively of said primary support member 27. Whereas the first mounting hole 27ma is used to fasten said primary support member 27 to said secondary support member 28 (shown in FIG.3), said second mounting hole 27mb is provided for receiving said mounting boss 27a. In an embodiment where said primary support member 27 is secured directly to a portion of said frame structure 20 including said bridge frame member 26, the first mounting hole 27ma can be eliminated. [36] Further, as may be seen in FIG.4 said primary support member 27 includes an L shaped flange 27b integrally formed at a lower end of said primary support member 27 and flanking said mounting boss 27a from at least two sides. Particularly, said L shaped flange 27b serves to restrict rotation motion of said electronic unit 30 about said mounting boss 27a. Therefore, change in orientation of said electronic unit 30 due to rotation is prevented, and thereby damage to said electronic unit 30 because of fouling with neighbouring parts such as the fuel tank, a canister etc. is prevented. Moreover, loosening of fasteners used for securing said electronic unit 30 to said mounting boss 27a is also prevented as the L shaped flange 27b ensures there is no movement of the electronic unit 30 due to vehicle vibrations. At least a portion of the L shaped flange 27b also serves to support a base of said electronic unit 30 including said electrical coil 30a. Thus, even a large electronic unit 30 including said electrical coil 30a may be comfortably supported against the front collar 27ab and at least a portion of said L shaped flange 27b. Further, a support pip 27c is also provided to prevent rotation of said primary support member 27 about said secondary support member 28. Thus, change in orientation of the electronic unit 30 due to rotation/movement of the primary support member 27 is also prevented by said support pip 27c. In the present embodiment, said support pip 27c extends from a side adjacent to said first mounting hole 27ma. Further, since said electronic unit 30 is independently detachably attached to said primary support member 27 ease of assembly and disassembly of said electronic unit 30 is ensured. As a result, serviceability of said electronic unit 30 is also facilitated. [37] Further, said primary support member 27 includes a dimple 27d formed above said mounting boss 27a and is preferably formed in said upper portion of the primary support member 27. In order to prevent flexion due to overhang said dimple 27d is provided. Further, an S-bend 27e is formed along a periphery 27p of said primary support member 27 in proximity to said dimple 27d. Provision of said dimple 27d and said S-bend 27e aids in improving local stiffness of said primary support member 27. Thus, durability of the primary support member 27 receiving said electronic unit 30 is ensured.

Apart from the bridge frame member 26, said primary support member 27 can be directly supported against any other portion of the frame structure 20 and serve to support the electronic unit 30 as described in the above paragraphs. Thus, the primary support member 27 can be fitted to any frame structure without significant modifications to the frame structure. As a result, retro-fitability of said electronic unit 30 to any existing motorcycle using said primary support member 27 can be ensured.

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