Claims:WE CLAIM:
1. A vehicle (100), comprising:
a main tube (110) connected to a headtube (102) of the vehicle (100) and extending in a vehicle front-rear direction (D1);
a rear frame structure (120) connected to the main tube (110), the rear frame structure (120) comprising a pair of upper tubes (130, 130’) spaced apart in a vehicle width direction (W) and extending in the vehicle front-rear direction (D1), wherein each of the upper tube (130, 130’) being configured with a stepped profile; and
a utility box (140) configured to be disposed on the upper tubes (130, 130’) of the rear frame structure (120) for providing a space for storing one or more articles.

2. The vehicle (100) as claimed in claim 1, wherein the stepped profile of the upper tubes (130, 130’) comprises a flat portion (P1) and an inclined portion (P2) extending from the flat portion (P1) towards a rear of the vehicle (100).

3. The vehicle (100) as claimed in claim 2, wherein the inclined portion (P2) of the stepped profile of the upper tube (130, 130’) is disposed above a rear fender (150) of the vehicle (100).

4. The vehicle (100) as claimed in claim 1, wherein the utility box (140) comprises a bottom surface (142), said bottom surface (142) being configured to be in a stepped profile, the stepped profile being configured to conform with the stepped profile of the upper tubes (130, 130’).

5. The vehicle (100) as claimed in claim 4, wherein the utility box (140) comprises a pair of side walls (144, 144’), a front wall (146) and a rear wall (148) extending upwardly from the bottom surface (142) of the utility box (140).

6. The vehicle (100) as claimed in claim 1, wherein the upper tubes (130, 130’) are connected with one or more bridge tubes (160) extending in the vehicle width direction (W).

7. The vehicle (100) as claimed in claims 5 and 6, wherein each side wall (144, 144’) of the utility box (140) is provided with one or more cut-out portions (144’’) for accommodating the one or more bridge tubes (160) connected to the upper tubes (130, 130’).

8. The vehicle (100) as claimed in claim 1, wherein the upper tubes (130, 130’) of the rear frame structure (120) comprises one or more mounting points (132) for mounting a damper member (170) of the vehicle (100), each mounting point (132) of the upper tubes (130, 130’) include a gusset plate (134) connected to the upper tube (130, 130’).

9. The vehicle (100) as claimed in claim 1, wherein the one or more mounting points (132) are provided at a junction point connecting the flat portion (P1) and the inclined portion (P2) of the upper tubes.

10. The vehicle (100) as claimed in claim 1, wherein the utility box (140) is connected to the upper tubes (130, 130’) through one or more mounting brackets (180) disposed at a front end (122) and a rear end (124) of the rear frame structure (120).

11. The vehicle (100) as claimed in claims 4 and 9, wherein a portion (142A) of the bottom surface (142) of the utility box (140) is configured to form as a part of the rear fender (150) of the vehicle (100) when the utility box (140) is connected to the upper tubes (130, 130’) at the rear end (124) of the rear frame structure (120).

12. The vehicle (100) as claimed in claim 1, wherein the utility box (140) comprises a front portion (140A), an intermediate portion (140B) and the rear portion (140C).

13. The vehicle (100) as claimed in claims 11 and 12, wherein the front portion (140A) of the utility box (140) comprises a flat bottom portion (140A’), and both the intermediate portion (140B) and the rear portion (140C) comprises a curved bottom portion (140BC’), the curved bottom portion (140BC’) being configured to be the part of the rear fender (150) of the vehicle (100).

14. The vehicle (100) as claimed in claim 1, wherein the utility box (140) is having a length (Lu) not more than 600 mm and a height (Hu) not more than 200 mm, and a volume of at least 5 litres.

15. The vehicle (100) as claimed in claim 12, wherein the front portion (140A) of the utility box (140) is having a length (Lf) not more than 220 mm and a height (Hf) not more than 100 mm.

16. The vehicle (100) as claimed in claim 12, wherein the intermediate portion (104B) and the rear portion (140C) of the utility box (140) combinedly have a length (Li-r) not more than 380 mm and a combined height (Hi-r) not more than 200 mm.

17. The vehicle (100) as claimed in claim 16, wherein the rear portion (140C) of the utility box (140) is having a length (Lr) not more than 130 mm.

18. The vehicle (100) as claimed in claim 1, wherein the pair of upper tubes (130, 130’) being moved out laterally from an existing distance by about 15 – 20 mm.

19. An utility box (140) for a vehicle (100), comprising:
a bottom surface (142);
a pair of side walls (144, 144’);
a front wall (146);
a rear wall (148);
wherein the pair of side walls (144, 144’), the front wall (146) and the rear wall (148) are extended from the bottom surface (142) forming a utility space in the utility box (140); and
wherein the bottom surface (142) being configured to be in a stepped profile.

20. The utility box (140) as claimed in claim 19 comprising a front portion (140A), an intermediate portion (140B) and the rear portion (140C).

21. The utility box (140) as claimed in claim 20, wherein the front portion (140A) of the utility box (140) comprises a flat bottom portion (140A’), and both the intermediate portion (140B) and the rear portion (140C) comprises a curved bottom portion (140BC’), the curved bottom portion (140BC’) being configured to be the part of the rear fender (150) of the vehicle (100).

22. The utility box (140) as claimed in claim 19 has a length (Lu) not more than 600 mm and a height (Hu) not more than 200 mm, and a volume of at least 5 litres.

23. The utility box (140) as claimed in claim 20, wherein the front portion (140A) of the utility box (140) is having a length (Lf) not more than 220 mm and a height (Hf) not more than 100 mm.

24. The utility box (140) as claimed in claim 19, wherein the intermediate portion (104B) and the rear portion (140C) of the utility box (140) combinedly have a length (Li-r) not more than 380 mm and a combined height (Hi-r) not more than 200 mm.

25. The utility box (140) as claimed in claim 19, wherein the rear portion (140C) of the utility box (140) is having a length (Lr) not more than 130 mm.

26. A method of assembling a utility box (140) on a vehicle (100), the method comprising:
providing a rear frame structure (120) comprising a pair of upper tubes spaced apart in a vehicle width direction (W) and extending in a vehicle front-rear direction (D1), the pair of upper tubes (130, 130’) being configured with a stepped profile;
mounting the utility box (140) on the upper tubes (130, 130’) of the rear frame structure (120).

27. The method as claimed in claim 26, wherein the utility box (140) is connected to the upper tubes (130, 130’) through one or more mounting brackets (180) disposed at a front end (122) and a rear end (124) of the rear frame structure (120) through one or more fasteners.

28. The method as claimed in claim 26, wherein the utility box (140) is mounted onto the upper tubes (130, 130’), the pair of upper tubes (130, 130’) being moved out laterally from an existing distance by about 15 – 20 mm.
, Description:FIELD OF THE INVENTION
[001] The present invention relates to a vehicle. More particularly, the present invention relates to a utility box for a two-wheeled vehicle.

BACKGROUND OF THE INVENTION
[002] Generally, in case of motorcycles having dual shock absorber, construction of the motorcycles does not have a liberty to provide an additional accommodation space like a storage box. However, few construction in the motorcycles has a small complementary storage box, which is well received by the customer and thus became an important feature for customer attractiveness.
[003] In order to provide full space utility box in the motorcycles, it may be required to alter or change the existing design and layout of the vehicle. One such change could be changing the structure of a frame assembly of the motorcycle. Another possible solution could be to relocate some parts inside the vehicle to maintain the same structure of the vehicle without changing vehicle layout. Thus, the said possible change or solution in the vehicle could be provided by repackaging of some vehicle components to provide the storage space. However, such configurations are expensive and also incurs higher amount of assembly time.
[004] Conventionally, in the motorcycles the utility box is provided for accommodating very small articles such as, but not limited to, documents or small tools. Such utility box may be having a capacity of 1 litre. However, the customer would be more delighted if the storage space is provided for accommodating both the small and medium sized objects in the motorcycles. Further, it would be prudent for a vehicle manufacturer to provide such a storage space without changing the vehicle layout substantially.
[005] Thus, there is a need in the art for a vehicle with a storage member or an utility box which address the aforementioned problems and limitations.

SUMMARY OF THE INVENTION
[006] In one aspect, the present invention is directed to a vehicle. The vehicle includes a main tube connected to a headtube of the vehicle and extending in a vehicle front-rear direction. The vehicle further includes a rear frame structure connected to the main tube. The rear frame structure includes a pair of upper tubes spaced apart in a vehicle width direction and extending in the vehicle front-rear direction. Each of the upper tube being configured with a stepped profile. The vehicle further includes a utility box configured to be disposed on the upper tubes of the rear frame structure for providing a space for storing one or more articles.
[007] In an embodiment, the stepped profile of the upper tubes includes a flat portion and an inclined portion extending from the flat portion towards a rear of the vehicle.
[008] In a further embodiment, the inclined portion of the stepped profile of the upper tube is disposed above a rear fender of the vehicle.
[009] In a further embodiment, the utility box includes a bottom surface. The bottom surface being configured to be in a stepped profile. The stepped profile being configured to conform with the stepped profile of the upper tubes.
[010] In a further embodiment, the utility box includes a pair of side walls, a front wall and a rear wall extending upwardly from the bottom surface of the utility box.
[011] In a further embodiment, the upper tubes are connected with one or more bridge tubes extending in the vehicle width direction.
[012] In a further embodiment, each side wall of the utility box is provided with one or more cut-out portions for accommodating the one or more bridge tubes connected to the upper tubes.
[013] In a further embodiment, the upper tubes of the rear frame structure includes one or more mounting points for mounting a damper member of the vehicle. Each mounting point of the upper tubes include a gusset plate connected to the upper tube.
[014] In a further embodiment, the one or more mounting points are provided at a junction point connecting the flat portion and the inclined portion of the upper tubes.
[015] In a further embodiment, the utility box is connected to the upper tubes through one or more mounting brackets disposed at a front end and a rear end of the rear frame structure.
[016] In a further embodiment, a portion of the bottom surface of the utility box is configured to form as a part of the rear fender of the vehicle when the utility box is connected to the upper tubes at the rear end of the rear frame structure.
[017] In a further embodiment, the utility box includes a front portion, an intermediate portion and the rear portion.
[018] In a further embodiment, the front portion of the utility box includes a flat bottom portion, and both the intermediate portion and the rear portion includes a curved bottom portion. The curved bottom portion being configured to be the part of the rear fender of the vehicle.
[019] In a further embodiment, the utility box is having a length not more than 600 mm and a height not more than 200 mm, and a volume of at least 5 litres.
[020] In a further embodiment, the front portion of the utility box is having a length not more than 220 mm and a height not more than 100 mm.
[021] In a further embodiment, the intermediate portion and the rear portion of the utility box combinedly have a length not more than 380 mm and a combined height not more than 200 mm.
[022] In a further embodiment, the rear portion of the utility box is having a length not more than 130 mm.
[023] In a further embodiment, the pair of upper tubes being moved out laterally from an existing distance by about 15 – 20 mm.
[024] In another aspect, the present invention is directed to an utility box for a vehicle. The utility box includes a bottom surface, a pair of side walls, a front wall, a rear wall. The pair of side walls, the front wall and the rear wall are extended from the bottom surface forming a utility space in the utility box. The bottom surface being configured to be in a stepped profile.
[025] In yet another aspect, the present invention is directed to a method of assembling a utility box on a vehicle. The method includes providing a rear frame structure having a pair of upper tubes spaced apart in a vehicle width direction and extending in a vehicle front-rear direction. The pair of upper tubes being configured with a stepped profile. The method further includes mounting the utility box on the upper tubes of the rear frame structure.
[026] In an embodiment, the utility box is connected to the upper tubes through one or more mounting brackets disposed at a front end and a rear end of the rear frame structure through one or more fasteners.
[027] In an embodiment, the utility box is mounted onto the upper tubes. The pair of upper tubes being moved out laterally from an existing distance by about 15 – 20 mm.

BRIEF DESCRIPTION OF THE DRAWINGS
[028] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 illustrates a left side of a vehicle, in accordance with an embodiment of the present invention.
Figure 2 illustrates a top view of a frame structure of the vehicle shown in Figure 1, in accordance with an embodiment of the present invention.
Figure 3 illustrates a rear perspective view of the frame structure of the vehicle shown in Figure 2, in accordance with an embodiment of the present invention.
Figure 4 illustrates an exploded view of the frame structure of the vehicle with a utility box to be mounted on an upper tubes of a rear frame structure, in accordance with an embodiment of the present invention.
Figure 5 illustrates a rear perspective view of the frame structure of the vehicle with the utility box mounted on an upper tubes of a rear frame structure, in accordance with an embodiment of the present invention.
Figure 6 illustrates a rear perspective of the vehicle with the utility box mounted on an upper tubes of a rear frame structure, in accordance with an embodiment of the present invention.
Figures 7 and 9 illustrate perspective view of the utility box of the vehicle, in accordance with an embodiment of the present invention.
Figures 8 and 10 illustrate a left side view of the utility box of the vehicle, in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
[029] Various features and embodiments of the present invention here will be discernible from the following further description thereof, set out hereunder. In the ensuing exemplary embodiments, the vehicle is a two-wheeled vehicle like a saddle type two-wheeler. However, it is contemplated that the disclosure in the present invention may be applied to any type of saddle type two-wheeled vehicle which may be driven by an Internal combustion engine or an electric batteries capable of accommodating the present subject matter without defeating the scope of the present invention.
[030] The present invention relates to a vehicle. More particularly, the present invention relates to a storage unit or an utility box in a two-wheeled vehicle.
[031] Figure 1 illustrates an exemplary saddle-type vehicle 100, in accordance with an embodiment of the invention. The terms “saddle type vehicle” and “vehicle” are interchangeably used in this disclosure. However, both the terms “saddle type vehicle” and “vehicle” are one and the same. The term “vehicle” is used for brevity. The vehicle 100 includes an Internal Combustion (IC) engine 12 that is vertically disposed. In the illustrated embodiment, the IC engine 12 is a single-cylinder type IC engine. The saddle type vehicle 100 further includes a front wheel 14, a rear wheel 16, a vehicle frame 22 (shown in Figure 2), a seat assembly 18 and a fuel tank 46. The vehicle frame 22 includes one or more frame elements including, but not limited to, a headtube 102 and a main tube 110 connected to the headtube 102. The headtube 102 supports a steering shaft (not shown) and two telescopic front suspensions 26 attached to the steering shaft through a lower bracket (not shown). The two telescopic front suspensions 26 support the front wheel 14. The upper portion of the front wheel 14 is covered by a front fender 28 mounted to the lower portion of the telescopic front suspension 26 at the end of the steering shaft. A handlebar 30 is fixed to an upper bracket (not shown) and can rotate to both sides of the vehicle 100. A head light 32, a visor guard (not shown) and an instrument cluster (not shown) are arranged on an upper portion of the headtube 102. The vehicle frame 22 further includes a downtube 44 that is configured to be located in front of the IC engine 12 and extends slantly downward from the headtube 102. The main tube 110 of the vehicle frame 22 is located above the IC engine 12 and extends rearward from headtube 102. In an embodiment, the IC engine 12 is mounted vertically, with a cylinder block (not shown) extending vertically above a crankcase (not shown). In an alternative embodiment, the IC engine 12 is mounted horizontally (not shown) with the cylinder block extending horizontally forwardly from the crankcase. In an embodiment, the cylinder block is disposed rearwardly of the downtube 44.
[032] The fuel tank 46 of the vehicle 100 is mounted on a horizontal portion of the main tube.110. A rear swing arm 34 is connected to the vehicle frame 22 to swing vertically, and a rear wheel 16 is connected to a rear end of the rear swing arm 34. Generally, the rear swing arm 34 is supported by a mono rear suspension or through two suspensions 170 on either sides of the saddle type vehicle 100 (as illustrated in the present embodiment). An exhaust pipe (not shown) of the vehicle 100 extends vertically downward from the IC engine 12 up to a point and then extends below the IC engine 12, longitudinally before terminating at a muffler unit (not shown). The muffler unit (not shown) is typically disposed adjoining the rear wheel 16. The rear wheel 16 arranged below seat assembly 18 rotates by a driving force of the IC engine 12 transmitted through a drive, for example a chain drive (not shown) from the IC engine 12. A rear fender 150 is disposed above the rear wheel 16.
[033] Further, a taillight unit 33 is disposed at an end of the saddle type vehicle 100 and at a rear portion of the seat assembly 18. A grab rail 37 is also provided towards the rear portion of the seat assembly 18 and above the taillight unit 33. In an embodiment, below the seat assembly 18 of the vehicle 100, an utility box 140 (shown in Figures 4 – 10) is disposed.
[034] Referring now to Figures 2 and 3, perspective views of the frame member 22 of the vehicle 100 in accordance with an embodiment of the present invention are disclosed. As illustrated, the main tube 110 is connected to the headtube 102 of the vehicle 100 and extending in a vehicle front-rear direction D1. The frame member 22 of the vehicle 100 further includes a rear frame structure 120 (shown in Figures 2, 3 and 4) which is connected to the main tube 110. In an embodiment, the rear frame structure 120 includes a pair of upper tubes 130, 130’ spaced apart in a vehicle width direction W and extending in the vehicle front-rear direction D1. As can be seen in the Figure 4, each of the upper tube 130, 130’ is configured with a stepped profile.
[035] The stepped profile of the upper tubes 130, 130’ includes a flat portion P1 and an inclined portion P2. The inclined portion P2 is extending from the flat portion P1 towards a rear of the vehicle 100. The inclined portion P2 of the stepped profile of the upper tube 130, 130’ is disposed above the rear fender 150 of the vehicle 100. The upper tubes 130, 130’ are connected with one or more bridge tubes 160 extending in the vehicle width direction W. In the illustrated embodiments in Figures 2 – 6, the vehicle 100 includes one bridge tube 160 connected between the upper tubes 130, 130’ in the vehicle width direction W.
[036] In an embodiment shown in Figure 3 – 6, the upper tubes 130, 130’ of the rear frame structure 120 includes one or more mounting points 132 for mounting a damper member 170 (shown in Figures 1 and 6) of the vehicle 100. Each mounting point 132 of the upper tubes 130, 130’ include a gusset plate 134 connected to the upper tube 130, 130’. In an exemplary embodiment, the one or more mounting points 132 are provided at a junction point connecting the flat portion P1 and the inclined portion P2 of the upper tubes 130, 130’. In some embodiments of the present invention, the utility box 140 is connected to the upper tubes 130, 130’ through one or more mounting brackets 180 (shown in Figures 3 – 5) disposed at a front end 122 and a rear end 124 of the rear frame structure 120. The utility box 140 and the mounting brackets 180 are connected through one or more fasteners (not shown) or any other method known in the art.
[037] Referring to Figures 4 – 6, the vehicle 100 includes the utility box 140 below the seat assembly 18. The utility box 140 is configured to be mounted onto the upper tubes 130, 130’ of the rear frame structure 120. In an embodiment, the utility box 140 is configured to be disposed on the upper tubes 130, 130’ of the rear frame structure 120 for providing a space for storing one or more articles. The term “article” as used herein may include, but not limited to, one or more documents, a first aid kit, tools of varying sizes used for the vehicle 100.
[038] Figures 7 – 10 illustrate various view of the utility box 140 of the vehicle 100. As shown in Figure 7, the utility box 140 includes a bottom surface 142 which is configured to be in a stepped profile such that the stepped profile is configured to conform with the stepped profile of the upper tubes 130, 130’ (shown in Figures 5 and 6). The utility box 140 further includes a pair of side walls 144, 144’, a front wall 146 and a rear wall 148 extending upwardly from the bottom surface 142 of the utility box 140. Thus, forming a utility space in the utility box 140.
[039] The utility box 140 includes a front portion 140A, an intermediate portion 140B and the rear portion 140C (shown in Figure 10). In the illustrated embodiment, the front portion 140A of the utility box 140 includes a flat bottom portion 140A’ (shown in Figure 9), and both the intermediate portion 140B and the rear portion 140C includes a curved bottom portion 140BC’ (shown in Figure 9). The curved bottom portion 140BC’ is configured to be the part of the rear fender 150 of the vehicle 100. In other words, as shown in Figures 6 and 9, a portion 142A of the bottom surface 142 of the utility box 140 is configured to form as a part of the rear fender 150 of the vehicle 100 when the utility box 140 is connected to the upper tubes 130, 130’ at the rear end 124 of the rear frame structure 120.
[040] In an embodiment as shown in Figures 5 and 6, each side wall 144, 144’ of the utility box 140 is provided with one or more cut-out portions 144’’ for accommodating the one or more bridge tubes 160 connected to the upper tubes 130, 130’. In the illustrated embodiments, there is one cut-out portion 144” provided on each side wall 144, 144’ of the utility box 140. The cut-out portion 144” is in substantially semi-circular shape which can accommodate the bride tube 160 of the frame structure 22.
[041] In some exemplary embodiment of the present invention as shown in Figure 10, the utility box 140 is having a length Lu not more than 600 mm and a height Hu not more than 200 mm, and a volume of at least 5 litres. In an exemplary embodiment, the front portion 140A of the utility box 140 is having a length Lf not more than 220 mm and a height Hf not more than 100 mm. In another exemplary embodiment, the intermediate portion 104B and the rear portion 140C of the utility box 140 combinedly have a length Li-r not more than 380 mm and a combined height Hi-r not more than 200 mm. In yet another exemplary embodiment, the rear portion 140C of the utility box 140 is having a length Lr not more than 130 mm. In still another exemplary embodiment, the pair of upper tubes 130, 130’ being moved out laterally from an existing distance by about 15 – 20 mm.
[042] In another aspect, the present invention is directed to a method of assembling the utility box 140 on the vehicle 100. The method includes providing the rear frame structure 120 having the pair of upper tubes 130, 130’ spaced apart in the vehicle width direction W and extending in the vehicle front-rear direction D1. The pair of upper tubes 130, 130’ is configured with the stepped profile. The method further includes mounting the utility box 140 on the upper tubes 130, 130’ of the rear frame structure 120. In an embodiment, the utility box 140 is connected to the upper tubes 130, 130’ through one or more mounting brackets 180 disposed at the front end 122 and at the rear end 124 of the rear frame structure 120 through one or more fasteners. In an embodiment, the utility box 140 is mounted onto the upper tubes 130, 130’ which are moved out laterally from an existing distance by about 15 – 20 mm, thereby maintaining existing dimension of the vehicle 100 and components of the damper member 170 mounted at the rear of the vehicle 100 and an air cleaner (not shown) of the vehicle 100. In some embodiments of the present invention, the air cleaner is rerouted below the bridge tube and thus providing minimal change in the dimension and/or layout of the frame structure of the vehicle 100.
[043] Advantageously, the shock absorbers or the damper members are provided below the upper tubes, and the upper tubes are widened to accommodate the storage box. Thus, width of the vehicle is not changed and the twin shock mounting point is same as the conventional frame. However, the upper tubes are moved out by 15 mm approximately which provides space for the utility box. Thus, the present invention provides the utility box without changing vehicle layout. In other words, the present invention provides an advantage of improved utility space while maintaining the conventional layout of the vehicle, which is also achieved by rerouting the existing design of the air cleaner to get the volume without changing the layout of the air cleaner and thereby locating the utility box just above the rear wheel. In one embodiment, the utility box is accessed by opening the vehicle seat in an upward direction and thereby provides easy accessibility of the utility box to the user of the vehicle.
[044] The utility box is designed to have a bottom portion, which acts as a part of rear fender. Thus, the part of the utility box having the bottom end mounting provides a space advantage. Further, the utility box having the stepped profile conforming the shape of the upper tube provides an advantage of maintaining dimensions in the vehicle and to achieving the volume of approximately 5 litres.
[045] While assembling the utility box to the vehicle, the utility box is assembled first, then the air cleaner and thereafter the shock absorber or damper member. This provides an advantage of no alternation or no dimensional change in the components of the vehicle and ease of assembling.
[046] The utility box having the cut-out portions in the side walls allow the bridge member of the frame structure to be accommodated in the cut-out portions without changing the layout of the frame structure and also reduces the part count of the vehicle by reducing the number of fasteners to be used to mount the utility box on the vehicle.
[047] The utility box in the present invention does not require additional support structure at lower ends, because a wheel hugger is present supporting the utility box.
[048] The stepped structure at the rear frame structure and between the upper tubes and disposed above a rear fender of the vehicle gradually extends from the flat portion to the inclined portion at the end. The inclined portion/profile enables the seat height to remain same. Also, the inclined profile restrict fouling of the wheel hugger at full bump condition and provides an optimum clearance.
[049] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.