GB2500954A

GB2500954A - Bicycle with planar frame sides

Info

Publication number: GB2500954A
Application number: GB1219866.9A
Authority: GB
Inventors: Vikram Shah
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-11-05
Filing date: 2012-11-05
Publication date: 2013-10-09
Anticipated expiration: 2032-11-05
Also published as: GB201219866D0; GB2500954B

Abstract

A bicycle 10 comprises a frame 12, a front wheel 22, a rear wheel 24, a metallic head tube 14 and a steering column 16 pivotally mounted within the head tube 14, the frame 12 including a pair of lamina members 28, 30 attached to each other and mounted to the head tube 14, the lamina members 28, 30 extending rearwardly from the head tube 14 at an acute angle to each other, the lamina members 28, 30 being adjacent at the head tube 14 and spaced apart at the rear of the bicycle 10. The lamina members 28 may be wooden, and the space formed between them may house a battery and controller for use with an electric drive motor 38.

Description

BICYCLE

The present invention relates to a bicycle and particularly but not exclusively to a balance bicycle.

BACKGROUND TO THE INVENTION

It is weB-known that bicydes are an advantageous form of transport. They are environmentally friendly, economical and allow for fast travel, even in heavy traffic.

However, many commuters still choose to travel by car instead of by bicycle.

Reasons for this choice indude the limited amount of luggage which can be carried on a bicycle and the physical effort which is required to propel the machine.

Baskets and panniers both provide for a certain amount of luggage to be tnmsported by a cyclist. However, these can make the bicycle top-heavy, and can upset the balance of the bicycle so that it is difficult to ride.

Electric bicycles seek to reduce the amount of physical effort involved in cycling.

However, electric bicycles have failed to gain widespread popularity due to their high cost. Electric bicycles also necessitate the carriage of batteries, with the above described problems. Electric bicycles are generally large and heavy, so a commuter who lives in, for example, an upstairs flat with no ground-level storage will struggle to get the bicycle up the stairs.

It is an object of this invention to reduce or substantially obviate the above mentioned problems.

STATEMENT OF INVENTION

According to the present invention, there is provided a bicycle comprising a frame, a front wheel, a rear wheel, a metallic head tube and a steeling column pivotally mounted within the head tube, the frame including a pair of lamina members attached to each other and mounted to the head tube, the lamina members extending rearwardly from the head tube at an acute angle to each other, the amina members being adjacent at the head tube and spaced apart at the rear of the bicycle.

The metallic head tube and steering column provide for the type of steering alTangement usually found on conventional full-sized adult bicycles. The front wheel is able to pivot at least 90 degrees in each direction, which is more than enough to facilitate good control of the bicycle. The steering column is mounted on bearings within the head tube, to provide for effortless steering at all speeds. The frame made from lamina members provides an attractive shape for the bicycle, and is Hghtweight and economic in terms of materials used.

The rear section of the frame may form a wheel fork, the rear whed being rotatably mounted between the two lamina members, Each lamina member may have a fork end at its rear. The fork end may be a different material from the rest of the lamina member, and may be at an angle to the larnina member. The fork end may be metallic.

By mounting the wheel between the larnina members, the wheel is securely attached to the frame, and also holds the sections of the frame together at the rear end of the bicyde.

A seat may be provided, mounted from the centre of the frame between the lamina members. The seat may be mounted from a seat mount, which may be bolted between the lamina members. As well as supporting the seat, the mount fixes the space between the lanilna members at the point where the seat is mounted.

An electric motor may be provided for propelling the bicycle. The electric motor allows the bicycle to be used for commuting, without the need to provide pedals.

A battery may be provided for powering the electric motor, and may be located between the lanilna frame members. The space between the lamina members provides a convenient void in which the battery may be mounted. Centrally mounting the battery in this space ensures that the mass of the bicycle is balanced. Additional

I

space may be available between the amina frame members, which may be used to transport items on the bicycle. The centrally located luggage location which is low down on the bicycle frame is advantageous compared with a basket or pannier, since the balance of the bicycle is substantially unaffected and the bicycle is easy to ride, even with a fairly heavy payload.

A tray may be attached to the underside of the frame, between the larnina frame members, for supporting the battery or other payload.

The bicycle may not include pedals, that is, the bicycle may be a balance bicycle.

Pedals are unnecessary where an electric motor is provided, and omitting pedals reduces the mechanical complexity of the device, reducing the cost of the product and improving reliability. A full-sized adult electric bicycle suitable for commuting can therefore be produced at a much lower cost than previously realized. The wheels of the bicycle may be between 18 inches and 28 inches in diameter, which is a suitable range of sizes for adult nders.

The lamina members of the frame may be made from wood, and may include at least one laminated sheet of flexible plywood. Wood is an economical and environmentally-frienWy natural materiaL It is found to be particulady suitable for use as a bicycle frame, since it is naturally flexible. The wooden frame therefore absorbs shock caused by using the bicycle on uneven road surfaces. This reduces or negates the need for a traditional suspension, for example springs or dampers. on the bicyde, further reducing the cost of manufacture.

A first set of pegs may be mounted on the frame. One peg may be positioned on either side of the frame, extending outwardly to form a footrest for a rider to rest his feet on. A second set of pegs may be mounted rearwards of the first set of pegs. It is found that a set of pegs close to the front of the frame provides for a comfortable nding position. However, the rider's legs may obstruct the front wheel when cornering. The second set of pegs allows for the feet to rest in an area where they do not obstruct the front wheeL whilst the bicycle is being ridden around a corner.

DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made by way of example only to the accompanying drawings, in which: Figure 1 shows a perspective view of a bicycle; Figure 2 shows a plan view from above of the bicycle of Figure 1; Figure 3 shows a close-up view of a head tube and part of a frame, forming part of the bicyde of Figure 1; Figure 4 shows a close-up view of the rear wheel of the bicycle of Figure 1, where it attaches to the frame; Figure 5 shows a close-up view of the top part of the frame of the bicycle of Figure i; and Figure 6 shows a dose-up view of a cavity within the frame of the bicycle of Figure 1.

DESCRIPTION OF PREFERRED EMBODIMENT

Refening firstly to Figures 1 and 2, a balance bicycle is indicated generally at 10.

The balance bicycle 10 comprises a frame 12, a head tube 14, a steering column 16, handlebars 18, a front fork 20, a front wheel 22, a rear wheel 24, and a seat 26. The frame 12 comprises two larnina members 28, 30 which are adjacent at the front of the bicycle 10, and spaced apart at the rear.

The handlebars 18, head tube 14, steeling column 16, front fork 20 and front wheel 22 provide a steering mechanism as is conventionally found on many full-sized adult bicycles.

As shown in Figure 3, the lamina members 28, 30 of the frame are attached to the head tube 14 by means of two metallic clamping plates 32. Each clamping plate is welded to the head tube, and extends rearwardly parallel to one of the lamina members 28, 30. The lamina members 28, 30 are therefore sandwiched between the clamping plates. Bolts 33 pass through the clamping plates 32 and lamina members 28, 30, to h&d the lamina members securdy together and to damp them to the head tube 14. The clamping plates 32 are stylised, that is, they are cut to give the impression of flames.

The lamina members 28, 30 extend rearwardly from the head tube 14 at an acute angle to each other. The lamina members 28, 30 therefore extend away from each other as they extend away from the front of the bicycle. The surface of each amina member forms a compound curve, the curve of one lamina member mirroring the curve of the other. At the rear of the bicycle, the lamina members are spaced apart and the rear wheel 24 is mounted between the members 28, 30 on metallic fork ends 40, as shown in Figure 4. The metallic fork ends 40 are bolted to the lamina members 28, 30. The fork ends are at a slight angle to the surface of the larnina member, so that the fork ends are parallel to each other, despite the curve of the lamina members.

Referring now to Figure 5, a seat mount 42 is disposed between the lamina members 28, 30, substantially haff way between the front and the rear of the frame 12. The seat mount comprises a pair of metallic blocks, with a semi-cylindrical cut-out in each block. The blocks about each other, with the two semi-cylindrical cut-outs combining to form a substantially cylindrical socket. A seat stem 44 is received in the cylindrical socket, and the metallic blocks of the seat mount 42 are clamped together to retain the seat stem 44. Bolts pass through the lamina members 28, 30 and the seat mount 42 to secure the seat mount 42 between the larnina members. The seat mount serves not only as a mounting point for the seat, but also to fix the spacing between the lamina members 28, 30 at a point substantially half way between the front and rear ends of the frame 12. This ensures that the bicycle frame 12 retains its shape in use and gives it enhanced rigidity.

The lamina members 28, 30 are each made from two sheets of flexible plywood separated by a sheet of micro ply. The flexible plywood and micro ply are glued together, and the resulting sheet is vacuum formed to create the curved surface. The curved surface of each lamina member 28. 30 incorporates both sweeping and compound curves, which results in a stiff frame.

A cover plate 46 is screwed to the top edge of the frame 12, in front of the seat. The cover plate 46 serves to join the lamina members 28, 30 together and to keep the spacing between them fixed. The cover plate also provides a convenient mounting point for controls and other electrica' components which need to be accessible. In the embodiment shown, a battery is&ator switch 48 and a fuse holder 50 are mounted to the cover plate 46.

Similar cover p'ates (not shown) are screwed to the bottom edge of the frame 12. The cover plates on the bottom of the frame are attached both in front of and behind the seat, and allow the void between the lamina members 28. 30 to be used for storage.

As can be seen in Figure 6, there is extra space available for the transportation of luggage, above the batteries 36, In embodiments without batteries, an even greater luggage space may be provided in this area. The lower cover plates also resist ingress of mud and water.

The bicycle is propelled by an electric motor 38, which is mounted in the rear wheel hub. A battery 36 for powering the motor is disposed in a cavity between the amina members 28, 30, as best seen in Figure 6. The cavity between the lamina members 28, 30 is an excellent location for battery storage, since it is low down on the bicycle and also centraL The mass of the battery will not therefore cause undue interference in the handling of the bicycle. A switch 34 for activating the motor 38 is provided on the handlebars 18 of the bicycle 10. The bicycle incorporates a regenerative braking system, which increases the power of the braking available to slow the bicycle, and also recharges the battery from energy which would otherwise be wasted. It may also include a conventional braking system, for example disc or rim brakes.

The bicycle is lightweight, uses few component parts, and can therefore be manufactured at very low cost. An attractive electric bicycle is provided with natural suspension in the frame.

Claims

CLAIMS1. A bicycle comprising a frame, a front wheel, a rear wheel, a metallic head tube and a steering column pivotally mounted within the head tube, the frame including a pair of lamina members attached to each other and mounted to the head tube, the lamina members extending rearwardly from the head tube at an acute angle to each other, the lamina members being adjacent at the head tube and spaced apart at the rear of the bicycle.
2. A bicycle as claimed in claim 1, in which a rear section of the frame forms a wheel fork, the rear wheel being rotatably mounted between the two lamina members.
3. A bicycle as claimed in claim 1 or claim 2, in which a seat is provided, mounted from the centre of the frame, between the larnina members.
4. A bicycle as claimed in any of the preceding claims, in which an electric motor is provided for propelling the bicycle.
5. A bicycle as claimed in claim 4. in which a battery is provided for powering the electric motor, and is located between the lamina members of the frame.
6. A bicycle as claimed in claim 5. in which a tray is attached to the underside of the frame, for supporting the battery between the lamina frame members.
7. A bicycle as claimed in any of the preceding claims, which does not include pedals.
8. A bicycle as claimed in any of the preceding claims, in which the wheels are between 18 inches and 28 inches in diameter.
9. A bicycle as claimed in any of the preceding claims, in which the lamina members of the frame are made from wood.
10. A bicycle as chimed in claim 9, in which each of the hmina members of the frame are made from at least one laminated sheet of flexible plywood.
Ii, A bicycle as claimed in any of the preceding claims, in which a first set of pegs are mounted on either side of the frame for a rider to rest his feet.
12. A bicycle as claimed in claim 11, in which a second set of pegs are mounted on either side of the frame, rearwards of the first set of pegs.
13. A bicycle substantially as described herein with reference to and as illustrated in Figures ito 6 of the accompanying drawings.Amendments to the claims have been filked as followsCLAIMS1. A balance bicycle comprising a frame, a front wheel, a rear wheel, a metallic head tube and a steering column pivotally mounted within the head tube, the frame including a pair of lamina members attached to each other and mounted to the head tube, the lamina members extending rearwardly from the head tube at an acute angle to each other, the lamina members being adjacent at the head tube and spaced apart at the rear of the bicycle, the rear section of the frame forming a wheel fork, the rear wheel being rotatably mounted between the two lamina members.2. A balance bicycle as claimed in claim I, in which a first set of pegs are mounted on either side of the frame for a rider to rest his feet.3. A balance bicycle as claimed in claim 2, in which a second set of pegs are mounted on either side of the frame, rearwards of the first set of pegs.Io 4. A balance bicycle as claimed in any of the preceding claims, in which a seat is provided, mounted from the centre of the frame, between the lamina members.5. A balance bicycle as claimed in any of the preceding claims, in which an electric motor is provided for propelling the bicycle.6. A balance bicycle as claimed in claim 5, in which a battery is provided for powering the electric motor, and is located between the lamina members of the frame.7. A balance bicycle as claimed in claim 6, in which a tray is attached to the underside of the frame, for supporting the battery between the lamina frame members.8. A balance bicycle as claimed in any of the preceding claims, in which the wheels are between 18 inches (45.7cm) and 28 inches (71.1cm) in diameter.9. A balance bicycle as claimed in any of the preceding claims, in which the lamina members of the frame are madc from wood.10. A balance bicycle as claimed in claim 9, in which each of the lamina members of the frame are made from at least one laminated sheet of plywood.11. A bicycle substantially as described herein with reference to and as illustrated in Figures 1 to 6 of the accompanying drawings. C')N-(1