Claims:WE CLAIM :

1. A bicycle with a seat supported by seat pillar (8) comprising of :-

a. a front frame portion (1) with a pair connecting support rod (1c,1c) attached to seat pillar (8) with a seat clamp (1a) at one end and each of its other end affixed with a sheet metal (1b,1b),
b. a rear frame portion having a U shaped tubular carrier rod (3), its two ends attached detachably to the pair of sheet metal (1b,1b) with combination of a shaft rod, a spring and a knob arrangement, so that the rear frame portion is pivotably connected to the front frame portion with a pivot point position therein in between, and rear frame portion being moveable between a first extended horizontal position in which rear frame portion is horizontally planar with front frame portion which is “carrier position”, and a second extended vertical position in which rear frame portion (1) is at 90° with respect to front frame (1) which is “backrest position”,
the arrangement is such that the knob (6) and spring (5) mounted on the shaft rod (2) combinedly exerting a force on the rear frame portion (3) against the sheet metal (1b) of the front frame portion (1) and the pivot point to move the rear end of the rear frame portion (3) towards the front end when the knob is in second position, so that rear frame portion (3) is at 90° with respect to front frame (1) and acts a backrest and further retain the rear end of the rear frame portion (3) along the same horizontal plane as first frame portion (1) when the knob is in its first position, so that rear frame portion (3) acts as a carrier,
c. a carrier saddle assembly (7) supported detachably onto the U shaped carrier rod (3) of the rear frame portion and attached also to the cross plates (3a) of the rear frame portion, and
d. a safety cover (4) enveloping the shaft rod (2) and adapted to retain the aligned axis of the connecting supporting rod (1) of first frame portion and carrier shaft rod (2) of rear frame portion.
the said arrangement characterized in the hinge pivotal attachment of the rear frame portion with respect to front frame portion.
, Description:I. FIELD OF INVENTION

The described invention relates to back support and carrier elements of the bicycles. It relates to the means of having both these functionalities infused in one sub-assembly as per invention.

II. BACKGROUND OF THE INVENTION

The rider of a bicycle is able to socialize and have fun on the go when they can have company on their rides. This purpose can be achieved with the help of the providing an arrangement for a friend as a pillion. At the same time during longer rides for better comfort, a backrest is often opted for by the riders for ride comfort. The only drawback in these situations is a backrest serves as a hindrance to the pillion rider, and taking up unnecessary space. In this scenario the rider is not actually given a functional option wherein they can toggle between both experiences as per their requirement. This results in various accessories like carrier and backrest being assembled on the same bicycle without actually serving the functionality. The current industry does not have a backrest that can switch into a carrier at the click of a button.

Thus with the short comings and disadvantages of present bicycle passenger/pillion carriers, the present invention was conceived and one of its objectives is to provide an integrated carrier to be adaptable into a backrest by the rider.

It is yet another objective of the present invention to provide a passage carrier integrated as backrest which can be easily mounted or removed from a conventional bicycle using single hand tools or otherwise known tools.

Various other objectives and advantages of the present invention will become apparent to those skilled in the art as a more detailed description is set forth below.

III. SUMMARY OF THE INVENTION

The invention is a multipurpose backrest that converts into the rear seat for a bicycle, with most preferably a single step actuation but not limited with single step actuation. The single step actuation set up consists of a main bent tube with a cushioning mounted on it, connected to the main frame body with the help of a special hinge mechanism. However the same may be achieved with equivalent arrangement for multi-step actuation also

The carrier and the backrest as known in prior art have evolved from more cumbersome, rigid structures and need urgent improvement. Such an improved device has the highest demands for a compact, folded configuration while at a same time providing a safe, stable integrated carrier and backrest in its configuration.

The said assembly is designed to withstand the weight of a pillion on a bicycle and also converts to act as a backrest as and when needed.

This has been done with a joining mechanism with fasteners and actuators that are readily available in market, hence making it easy to commercialize the invention.

IV. DETAILED DESCRIPTION OF THE DRAWINGS

PARTS LIST
1 – Connecting Support rod
1.a Seat clamp
1.b Sheet metal formed part
1.c Steel rod
2 – Shaft rod
3 – Carrier rod
3.a Plate
4 – Safety Cover
5 – Spring
6 – Knob
7 – Carrier Saddle assembly
7.a Litlon foam
7.b Rexine cloth
7.c Fastener bolts
8 – Seat Pillar
9 – Push
10 – Position 1
11 – Position 2

PARTS DESCRIPTION

Connecting Support rod (1) is a cylindrical ERW tube of material thickness 1.02 welded along with seat clamp (1a) and sheet metal formed part (1b). In order to hold the tension between the two segments we have used a steel rod (1c) of dia 4.2 to hold these two tube in place and also to avoid misalignment issues.

Shaft rod (2) is Mild Steel rod machined to its shape made up of IS:5517 C10 GRADE with threaded end on one side to accommodate the know and a shank head on the other to restrict the entire rod from falling apart from the connecting support rod metal formed section (1b).

Carrier rod (3) is a support for carrier which is made up of ERW tubes with thickness if 1.02 and the ends flattened with slot holes to match sheet metal formed part (1b) and Shaft rod (2). This also consists of two plate to (3a) to accommodate the Carrier saddle assembly (7) and to provide support for pillion.

Safety cover (4) is essentially an enclosure for the mechanism to be kept hidden and also provide safety for end users whilst also serving as a guide to move the shaft rod (2) concentrically along the proper axis of both connecting support (1) and carrier rod (3). This is made up of preferably but not limited with materials such as polypropylene plastic with 15% Talc filled to have rigidity. In addition to its usage majorly viewed for safety aspects, it also acts as a washer between the moving metal parts there by reducing friction and any hindrance that may arise to constant abrasion for longer periods of time whilst also reducing the noise while actuating the mechanism. The material need not restricted only be talc filled PP, but may be materials such be glass filled nylon, or any other Polymer that can achieve the necessary rigidity. Hence all such equivalents are within the scope of this invention.

Spring (5) is closed ended coil compressive springs of thickness 1.2 made up of Spring steel with - IS: 4454 - SM GRADE of bright chrome plated finish. This functions as an actuation for the shaft rod (2) to move in when external force is applied to the knob (6) by the user and retract back effectively locking the mechanism in relevant position completely.

Knob (6) is the touch point for actuating the mechanism and is made up of soft plastic material polypropylene with self-threaded hole provided in the required limits so as to hold the spring in place with the right spring force constant. Designed to be actuated both with thumb or palm by the end user.

Carrier Saddle Assembly (7) is the support provided for the pillion to be seated which is made up of Litlon foam (7a) and covered with Rexine cloth (7b) material. This is fastened on top of carrier rod (3) with fasteners bolts (7c).

Seat Pillar (8) is an integral part of a bike which connects the bike frame with saddle section. The entire convertible backrest assembly is affixed onto the seat pillar. This acts as a support and also to hold the connecting rod (1) parallel to the ground.

V. DESCRIPTION OF THE INVENTION

Riders use the specials bicycles for fun, learning and short commute purposes. And sometimes over accessorizing a bicycle like with a big backrest prevents it from being used for other fun purposes like carrying a friend as a pillion. The existing backrests in the market occupy a horizontal space that prevents the user from keeping anything on the carrier. Rather than conventionally going with a detachable functionality, this invention has the novelty on providing three functions in one go which is to act as a back support, rear seat for pillion and as a carrier depending on the users’ needs covering most of the used case spectrum. This invention is also unique as it could go across other all the bikes and in not subject to specific category. It can be assembled on any bicycle and modified for manufacturing as per the target groups height and weight requirements in the industry.

The novelty of this invention is not only specific to the mechanism of actuation currently mentioned here owing to commercialization for the purpose of mass production. This could be achieved electronically to become a power actuated module rather than manual which is also covered under this patent. Likewise this could be also actuated with the help of hydraulics under the same mechanism which is also covered in this patent invention.

A passenger carrier for a bicycle is mounted behind the bicycle seat to the bicycle frame. The preferred passenger carrier includes in the preferred form to be operable as a backrest alternative to its performance as a passenger seat.

The invention has been described as detailed above but various embodiments and variations are possible beyond the preferred embodiments disclosed in this document. All such variations and modifications as obvious to the skilled person is within the scope of this invention. The applicant intends to rely upon specifications and the drawings submitted along with the specification.

In gist, the entirety of this Convertible backrest assembly consists of a Connecting support rod (1) which aids in providing support for the carrier assembly to be merged with seat pillar. A Shaft rod (2) which is the key to the mechanism followed here which is to actuate the carrier into a backrest for the kids to use as a part of safety and also revert the same as a carrier when needed. The shaft rod is actuated by the utilization of spring force, here we are using spring (5) made up of spring steel material. Spring is compressed and constrained to its position by a Knob (6) which actually is designed to suit the optimum spring force so as the user could actuate the mechanism with the right amount of force. Carrier saddle assembly (7) is mounted onto the carrier rod (3) for seating comfort. This assembly could be mounted to any seat pillar (8) with dia 25.4 across the kids bike platform.

The default assembly would be in carrier state where the mechanism is locked onto place in Position 1 as shown in fig 1.2.1. If the user wishes to convert the carrier into backrest, then it is done so by actuating the mechanism. User would need to push and hold onto the knob so that the shaft disengages from both connecting support rod (1) and carrier rod (3), while the user would actuate the carrier to its intended position 2 as shown in fig 1.2.2. Upon reaching this position the user releases the force applied onto the knob so that the mechanism gets back to its initial position with the function of Spring in action. This engages the shaft rod (2) back into its place by constraining itself between connecting support rod (1) and Carrier rod (3).

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all aspects as illustrative and not restrictive, reference being made to the claims rather than to the foregoing description to indicate the scope of the invention.