DESC:Technical Field
[1] The present subject matter described herein generally relates to a frame structure for a vehicle and particularly relates to a steering housing assembly of said frame structure.
Background
[2] Conventionally, two wheeled vehicles make use of metal tubes or tubes composed of metal alloys such as steel for forming a body frame thereof. Said tubes typically form a closed framework to interconnect various parts such as body covers, seat, engine etc. Besides, said tubes act as load bearing members which serve to take the impact during a vehicle crash.
[3] However, metal tubes are relatively heavy since they are formed by extrusion or rolling and seaming of steel or other metal alloys. Moreover, using tubular frame members also restricts the scope for aerodynamic improvements, as they are generally restricted to the use of tubes with circular cross sections. Additionally, conventional body frames are prone to having weak joints between respective tubes, said joints acting as points of stress.
[4] In light of above circumstances, there is a need to provide lighter frames with optimised load and weight distribution. Vehicle body frames are being increasingly replaced by light weight body frames made of composite materials such as carbon fibre or glass fibre. Particularly, in light weight body frames it is important to optimise load and weight distribution since certain parts of the body frame are subject to greater stress and load and it is necessary to reinforce such parts. For example, in vehicle riding conditions, considerable amount of stress is exerted on a steering housing. In a known art, in order to withstand said stress, said steering housing is made of high strength steel tubes, while rest of the body frame is made of composite material for achieving weight reduction. Additionally, making said steering housing of a steel tube also aids in ensuring that steering bearings are properly accommodated therein. However, providing steel tubes for steering housing contributes substantially to an increase in overall weight of the body frame.
[5] There is therefore a need to ensure proper accommodation of steering bearings while replacing steel tubes or metal alloys for steering housing, with composite material such as carbon fibre or glass fibre without compromising on strength of said steering housing.
Summary of the Invention
[6] The above invention has been made in view of the above circumstances.
[7] It is an object of the present invention to provide an integrated steering housing assembly which is light in weight, yet whose strength is uncompromised.
[8] It is yet another object of present invention to provide an integrated steering housing assembly in which steering races are capable of being comfortably and surely accommodated.
[9] It is one more object of the present invention to provide an integrated steering assembly which can be easily assembled, with fewer number of parts.
[10] With theabove and other objects in view, the present invention provides a vehicle including an integrated steering housing assembly adapted to accommodate a steering shaft of said vehicle. Said integrated steering housing assembly is provided at a foremost end of a body frame of the vehicle. As per an embodiment of the present invention, the integrated steering housing assembly includes a steering housing, a first integrated insert structure configured to be rigidly attached to a top portion of said steering housing, and a second integrated insert structure configured to be rigidly attached to bottom portion of said steering housing.
[11] The steering housing accommodates a steering shaft which is rotatably supported therein. In order to at least support said steering shaft, the first integrated insert structure and the second integrated insert structure are provided. As per an aspect of the present invention, the first integrated insert structure and the second integrated insert structure also serve to add strength to the steering housing.
[12] In the present embodiment, the first integrated insert structure and the second integrated insert structure are made of metal, while the steering housing is made of material other than a metal or an alloy. Thus, providing at least the first integrated insert structure and the second integrated insert structure as metal members in the steering housing, which is in turn made of a light weight composite material such as carbon fibre or glass fibre ensures that overall strength of the steering housing is not compromised. Moreover, said first integrated insert structure and said second integrated insert structure made of metal serve to support at least a top steering race and a bottom steering race respectively in the top portion and the bottom portion respectively of the steering housing.
[13] Further, in the present embodiment, the steering housing is provided with a non-circular cross section, for example a square cross section. Furthermore, in order to ensure that said top steering race and said bottom steering race, with a circular cross section each, be properly accommodated in the steering housing, said first integrated insert structure and said second integrated insert structure are configured to have a circular inner diameter and a square outer diameter.
[14] In the present embodiment, said first integrated insert structure includes a first circular slot formed in a first square base, and a steering lock mounting member rigidly attached to said square base. Further, said second integrated insert structure includes a second circular slot formed in a second square base, and a steering stopper rigidly attached to second circular slot. Thus, besides supporting the top steering race and the bottom steering race, the first integrated insert structure and the second integrated insert structure respectively support the steering lock mounting member and the steering stopper respectively.
[15] Thus, since the first integrated insert structure and the second integrated insert structure are rigidly attached to the steering housing, the total number of parts involved in the integrated steering housing assembly are few. Moreover, said steering housing assembly also does not involve the use of fasteners, thereby easing assembly operations and reducing assembly time.
[16] 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
[17] 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:
[18] FIG.1 illustrates a side view of a two wheeled vehicle in accordance with an embodiment of the present invention.
[19] FIG.2 illustrates a perspective view of a frame structure of said two wheeled vehicle in accordance with an embodiment of the present invention.
[20] FIG.3 illustrates a perspective view of an integrated steering housing assembly in accordance with an embodiment of the present invention.
[21] FIG.4 illustrates an exploded view of said integrated steering housing assembly in accordance with an embodiment of the present invention.
[22] FIG.5a illustrates a front view of a first integrated insert structure of said integrated steering housing assembly in accordance with an embodiment of the present invention.
[23] FIG.5b illustrates a cross sectional view of the first integrated insert structure of said integrated steering housing assembly in accordance with an embodiment of the present invention.
[24] FIG.6a illustrates a bottom view of the second integrated insert structure of said integrated steering housing assembly in accordance with an embodiment of the present invention.
Brief Description of the Invention
[25] Exemplary embodiments detailing features of the integrated steering housing assembly, 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 “upper”, “lower”, “right”, “left”, “front”, “forward”, “rearward”, “downward”, “upward”, “top”, “bottom” and like terms are used herein based on the illustrated state or in a standing state of the vehicle with a driver riding thereon unless otherwise elaborated. Furthermore, a longitudinal axis refers to a front to rear axis relative to said vehicle, while a lateral axis refers to a side to side, or left to right axis relative to the vehicle. Although, the present invention has been exemplified for a two wheeled vehicle, the same is applicable for other three and four wheeled vehicles. 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.
[26] Firstly a description is made of an entire schematic structure of a vehicle 10; say for example a two wheeled vehicle, with reference to FIG.1 & FIG.2.
[27] FIG.1 is a side view of the vehicle 10. The invention disclosed herein has been exemplified for a two wheeled vehicle such as a scooter type motorcycle. As shown in FIG.1, the vehicle 10 includes a frame structure 11 (shown in FIG.2), for example an underbone body frame structure, made of a composite material such asfibre reinforced resin, for example glass fibre or carbon fibre etc. However, in another embodiment, said body frame structure may be made of metal/alloy.
[28] Said frame structure 11 which forms a skeleton of the vehicle 10, is covered by different body covers. A front cover 1 is provided to cover a forward facing side of the frame structure 11 and is disposed above a front fender 2. A headlamp cover 3 is disposed above the front cover 1 to encompass a headlamp (not shown) and a handle bar 5 at least partially.
[29] Further, a leg shield 6 is disposed on a rear side of the front cover 1, which serves to protect a rider’s legs from running wind
[30] Left and right side covers 7 are disposed to cover left and right side surfaces of a rear portion of the frame structure 11.
[31] A seat 20 is disposed above the left and right side covers 7. A fuel tank (not shown) is arranged in the rear portion of the frame structure 11 with its sides covered by the left and right side covers 7. Further, a utility box (not shown) supported between a pair of side frames 17 (shown in FIG.2) of the frame structure 11, is disposed in front of the fuel tank and above an engine 22.
[32] The engine 22 is powered by an air fuel mixture sent in by a throttle body (not shown) to a combustion chamber of the engine 22. In the present embodiment the throttle body is a carburettor. However, in another embodiment, the throttle body can be an electronic fuel injection device.
[33] Further, combustion gases generated by the engine 22 are let out as exhaust from a muffler (not shown).
[34] A toggle link (not shown) is supported swingably on a lower side of the left and right side covers 7. A rear wheel 35is connected to the toggle link via the engine 22.
[35] With reference to FIG.2, a detailed description is given of the frame structure 11 in accordance with an embodiment of the present invention.
[36] As may be seen in FIG.2, the frame structure 11 includes an integrated steering housing assembly 12 provided at a foremost end thereof. Said integrated steering housing assembly 12 rotatably supports a steering shaft 18 which allows steering of the front wheel 25 (shown in FIG.1).
[37] A front fork 30 is rotatably supported to the steering shaft18. A handle bar assembly (not shown)provided above the front fork 30 allows steering of the front wheel 25.
[38] The frame structure 11 further includes a main frame 13 extending rearwardly and downwardly from a portion of said integrated steering housing assembly 12, a first cross bridge 14 extending sidewardly from either sides of said main frame 13, a pair of floor board support tubes 15 extending rearwardly and substantially perpendicularly to the first cross bridge 14, a second cross bridge 16 bridging the pair of floor board support tubes 15 at a rear end thereof, and the pair of side frames 17 extending rearwardly and inclinedly upwards from the second cross bridge 16.
[39] In the present embodiment, the frame structure 11 is a light weight structure, being composed of a composite material such as fibre, for example glass fibre or carbon fibre etc. Further, in the presentembodiment, besides the integrated steering housing assembly 12, other parts of the frame structure 11 have circular cross section. However, in another embodiment, the entire frame structure 11 may have a non- circular cross section.
[40] FIG.3 is a perspective view of the integrated steering housing assembly 12 in accordance with an embodiment of the present invention. As may be seen in FIG.3, the integrated steering housing assembly 12 includes a steering housing 12a, a first integrated insert structure 12b, and a second integrated insert structure 12c. Particularly, the steering housing 12a is adapted to accommodate the steering shaft 18 and the steering housing 12a annularly encloses at least a portion of the steering shaft 18 in an assembled condition. More particularly, the steering housing 12aroatatably supports said steering shaft18, said shaft passing through said first integrated insert structure 12b and said second integrated insert structure 12c.
[41] In the present embodiment the steering housing 12a has a non-circular cross section. Preferably, said steering housing 12a is provided with a square cross section. However, in another embodiment the steering housing 12a may be provided with a rectangular cross section. In yet another embodiment, the steering housing 12a may be provided with a quadrilateral cross section.
[42] Further, whereas the steering housing 12a is composed of a composite material such as fibre reinforced resin, for example carbon fibre or glass fibre etc., the first and second integrated insert structures 12b, 12c are composed of a metal or an alloy, which serve to improve overall strength of said steering housing 12a.
[43] FIG.4 is an exploded view depicting parts of said integrated steering housing assembly 12.
[44] In the present embodiment, said first integrated insert structure 12b and said second integrated insert structure 12c are adapted to support a top steering race 12bs and a bottom steering race 12cs respectively. Particularly, the first integrated insert structure 12b and said second integrated insert structure 12c are individually enmoulded tosaid steering housing 12a. Thus, said first integrated insert structure 12b and said second integrated insert structure 12c are enmoulded together with said steering housing 12a, so that at least a portion of said first integrated insert structure 12b and that of said second integrated insert structure 12c rest within a top recess 12at and a bottom recess 12ab respectively of said steering housing 12a. Thus, the steering housing 12a, said first integrated insert structure 12b, and said second integrated insert structure 12c together form a single integrated structure, without involving the use of any fasteners. Thus, no fasteners are used in the integrated steering housing assembly 12. Once the first integrated insert structure 12b and said second integrated insert structure 12c are secured to said steering housing 12a, the top steering race 12bs and said bottom steering race 12cs are press fitted thereto respectively.
[45] With reference to FIG.5a and FIG.5b the first integrated insert structure 12b is explained in detail. As may be seen in FIG.5a and FIG.5b, the first integrated insert structure 12b includes a first circular slot 12bc formed centrally in a first square base 12bd. Particularly, at least a portion of said first circular slot 12bc extends above an upper surface of said first square base 12bd, and receives the top steering race 12bs. Thus, the top steering race 12bs is supported around an outer periphery of said first circular slot 12bc and above the upper surface of said first square base 12bs.
[46] Structure of the first square base 12bd which compliments shape of said top recess 12at ensures that enmoulding is achieved therebetween. Particularly, the steering housing 12a is formed in a manner such that a top portion thereof, including said top recess 12at, is wider compared to acentral portion thereof so that enmoulding of said first integrated insert structure 12b can be easily performed. In other words, inner perimeter of the steering housing 12a is gradually increased away from the central portion of the steering housing 12a towards the top portion thereof.
[47] Further, the first integrated insert structure 12b includes a steering lock mounting member 12be. Particularly, the steering lock mounting member 12be enables mounting of a steering lock19(shown in FIG.2) to the first integrated insert structure 12b. A locking shaft provided in said steering lock 19 protrudes outwards to abut against a steering arrest lug (not shown) provided in a portion of the handlebar, thereby locking the handlebar by preventing pivotal rotation of the steering shaft 18 when an ignition key is rotated to lock said vehicle.
[48] In the present embodiment, the first integrated insert structure 12b is a single structure formed of a metal. Whereas, in one embodiment, said first integrated insert structure 12b may be formed by casting, in another embodiment, the same may be formed by welding a plurality of metal sheets together.
[49] With reference to FIG.6a, the second integrated insert structure 12c is explained in detail. As may be seen in FIG.6a, the second integrated insert structure 12c includes a second circular slot 12cc formed in a second square base 12cd. Particularly, the second circular slot 12cc is formed in a manner such that it is disposed in the centre of the second square base 12cd, and in a manner so that at least a portion of said second circular slot 12cc extends downwards from a bottom surface of the second square base 12cd. At least a portion of said second circular slot 12cc thus formed, receives the bottom steering recess 12cs from a bottom side thereof. Particularly, structure of the second square base 12cd enables enmoulding of the second integrated insert structure 12c to the steering housing 12a. To enable convenient enmoulding of said integrated insert structure 12c to the steering housing 12a, a bottom portion, including the bottom recess 12ab (shown in FIG.4), is provided with an inner perimeter wider than that of theinner perimeter of central portion of the steering housing 12a.
[50] Further, in the present embodiment, the second integrated insert structure 12c includes a steering stopper 12ce. The steering stopper 12ce protrudes from a portion of the second circular slot 12cc extending below the second square base 12cd. Particularly, it is ensured that the steering stopper 12ce faces a front side of the vehicle when the second integrated insert structure 12c is enmoulded in the bottom recess 12ab of the steering housing 12a. The steering stopper 12ce aids in ensuring pivotal movement of the steering shaft about the steering housing 12a. Particularly, said steering stopper 12ce comes in contact with an arrester lug provided in a lower bracket21 (shown in FIG.2) provided for assembly of the front fork 30 (shown in FIG.2), thereby arresting pivotal rotation of said steering shaft 18 when the steering lock is rotated to lock the vehicle.
[51] Similar to the first integrated insert structure 12b, the second integrated insert structure 12c is also a single structure formed of metalor alloy. Particularly, said second integrated insert structure 12c may be formed either by casting or by welding a plurality of metal sheets together.
[52] Thus, while the steering housing 12a is made of a composite material, the first and second integrated insert structures 12b & 12c are made of metal or alloy. Providing metal insert structures aids in improving overall strength of the steering housing, thereby enabling the same to withstand bearing load and stress.
[53] While the present invention has been shown and described with reference to the foregoing preferred embodiments, it will be apparent to those skilled in the art that changes in form, connection, and detail may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.
,CLAIMS:I/We Claim:
1. An integrated steering housing assembly (12) to house a steering shaft (18) of a vehicle (10);
characterized in that, said integrated steering housing assembly (12) integrally includes a steering housing (12a) annularly enclosing at least a portion of said steering shaft (18), a first integrated insert structure (12b) enmoulded to a top recess (12at) of said steering housing (12a), and a second integrated insert structure (12c) enmoulded to a bottom recess (12ab) of said steering housing (12a), wherein said first integrated insert structure (12b) and said second integrated insert structure (12c) are adapted to enable restricted pivotal motion of said steering shaft (18) about said steering housing (12a).
2. The integrated steering housing assembly (12) as claimed in claim 1, wherein said steering housing (12a) is composed of a composite material.
3. The integrated steering housing assembly (12) as claimed in claim 1, wherein said steering housing (12a) has a non-circular cross section.
4. The integrated steering housing assembly (12) as claimed in claim 3, wherein said steering housing (12a) has a top recess (12at) having an innerperimeter wider than inner perimeter of a central portion of said steering housing (12a).
5. The integrated steering housing assembly (12) as claimed in claim 3, wherein said steering housing (12a) has a bottom recess (12b) having an innerperimeter wider than inner perimeter of a central portion of said steering housing (12a).
6. The integrated steering housing assembly (12) as claimed in claim 1, wherein said first integrated insert structure (12b) is composed of a metal.
7. The integrated steering housing assembly (12) as claimed in claim 1, wherein said first integrated insert structure (12b) includes a first circular slot (12bc) formed centrally in a first square base (12bd).
8. The integrated steering housing assembly (12) as claimed in claim 1 or claim 7, wherein said first integrated insert structure (12b) includes a steering lock mounting member (12be) for enabling restricted pivotal motion of said steering shaft (18).
9. The integrated steering housing assembly (12) as claimed in claim 1, wherein said second integrated insert structure (12c) is composed of a metal and includes a second circular slot (12cc) formed in a second square base (12cd), and wherein at least a portion of said second circular slot (12cc) extends downwards from a bottom surface of the second square base (12cd).
10. The integrated steering housing assembly (12) as claimed in claim 1 or claim 9, wherein said second integrated insert structure (12c) includes a steering stopper (12ce) for enabling restricted pivotal motion of said steering shaft (18).