WO1997031815A1

WO1997031815A1 - Propulsion system for bicycles

Info

Publication number: WO1997031815A1
Application number: PCT/PT1997/000003
Authority: WO
Inventors: Antonino Da Silva Pinho
Original assignee: Antonino Da Silva Pinho
Priority date: 1996-02-29
Filing date: 1997-02-19
Publication date: 1997-09-04
Also published as: AU1739197A; BR9700278A; PT101840B; PT101840A

Abstract

The invention concerns a new propulsion system for bicycles, comprising the use of a larger bicycle frame (02), provided with an intermediate bar (03), which together with a lower bar will serve as the support to a metallic block (04) which serves as the base and attachment for all the mechanism. The mechanism comprises the use of two levers (06), supported and attached in each side of the block (04), which are provided in one of its ends of a pedal (08) and in the other lever rack (07). The levers (06) have reciprocated and synchronised movements, moving each one along a short and elliptical path, driving through the crank gears (10) that make the rotative axle (09) to rotate, transmitting its movement to the chain wheel (11) which by means of a second chain (13), that in its turn transmits it to the conventional chain wheel (12) from whose axle the pedals were suppressed. From this point the common traction system is in use. The synchronisation system of the levers (06) is assembled inside of the block (04).

Description

"Propulsion system for bicycles"

The present invention refers to a new propulsion system for bicycles called by its inventor "PEDALPINHO", which object is to improve its use conditions making it faster and less tiring and so, more useful and healthier.

The mechanism is applicable to any model from the simplest to the most sophisticate.

One of the main features of the system is the change of the pedal system using cranks with rotative movement by two levers (06) also driven by pedals (08), but which describe in its trajectory, alternatively upwards and downwards, an ellipse arch of an angle lower than 90°. The amplitude of such an angle is adjustable.

Each lever (06) has in one end a pedal (08) and in the other - the support base - a rack (07).

The model presents a larger frame than the conventional bicycles, reinforced with an intermediate bar (03) which supports the mechanism.

As the frame of the invention is larger than the conventional frame, the front wheel (01) must have a lower diameter than the back wheel.

Between the said intermediate bar (03) and the lower bar a metallic block (04) is assembled, this block being showed in detail in fig. 4 and it supports the entire system.

In that block are installed the two axles, which are the support bases, one (05) fixed for support and attachment of the levers <06) and the other one (09) rotative which is the attachment base for the gears (10) operating as a free wheel system which are driven by the rack (07) of the levers (06) transmitting the movement to the axle (09) where the chain wheel (11) is mounted, the movement being transmitted continuously to the other chain wheel (12) by means of a reinforced chain (13). This last wheel (12) (which should be of a smaller or the same size of the one that transmits it the movement) is attached to the conventional chain wheel axle on the opposite side from where the pedals were suppressed. Apart from this the conventional traction system is used.

The synchronisation mechanism for the levers is installed inside the block, with two small racks (14), attached to the axle sleeves (15), which function in parallel in the lateral portions of the block and inside it and which receive the movement from the levers installed in the end of the axle (05), having the axle sleeves thereon, become those more stable and extend its movements inside the block and synchronisation process takes place therein through the two racks (14), connected therebetween by means of a crown wheel (16). This way we should have the two pedals functioning with reciprocal movement always that the need for pedalling occurs. The crown wheel (16) functions across the block forming an 90^* angle with its base, the block should so be hollowed for that purpose.

For easier assembly the crown wheel should have in its back a metallic plate, with the width of the block, with an welded axle in the centre for centring the wheel, with some clearance for adjusting movements between that part and the plate. For mounting the block (04) fitted between the bars a cut in the block following a slanted line is needed, this line can be subjected to repositioning.

As an example, the following dimensions for the block could be used :

Length - 250 mm

Width - 130 mm

Height - 150 or 160 mm

Axles diameters (05 and 09) - 20 mm

Length of the axles - 200 mm For improving the strength of the axles the block should be compact only with the essential hollowings.

The crown wheel (16) has no use in the total of its 360", so it could be restrained to the essential.

For a movement of the levers (06) of approximately 55 cm length the system will allow the full rotation of the gear (10).

The forces ratio is more or less of 3:1, so for an applied force of 10 kg a 30 kg traction force is obtained.

A non limitating exemple of the invention is shown in the sole drawing sheet, in which:

Fig. 1 is a left side view of the bicycle according to the present invention;

Fig. 2 is a right side view of the bicycle of Fig. 1;

Fig. 3 is an inside view of the levers and the respective synchronisation elements;

Fig. 4 is a sectional perspective view of the block.

Claims

1 - The system of propulsion for bicycles characterised by comprising essentially the use of an larger frame (02) provided with an intermediate bar (03), a metallic block (04) for support and attachment of the mechanism, levers (06) for pedalling; a second chain wheel (10) and a second reinforced chain (13) for transmitting the movement to the conventional chain wheel (12).

2 - The system as claimed in claim 1 characterised by pedalling is performed by means of two mechanical levers (06) each provided with a pedal (08) in one end and a crank (07) in the other end, describing the levers, whose movement is reciprocated and synchronised, a short elliptical path having an angular extent lower than 90^*.

3 - The system as claimed in the claims 1 and 2 characterised in that the metallic block (04) is assembled in between the reinforce intermediate bar (03) and the lower bar of the frame.

4 - The system as claimed in claims 1 to 3 characterised in that the metallic block is crossed through by two support axles, the fixed axle (05) supporting and attaching the levers (06) and the rotative axle (09) supporting and attaching the gears (10) and the chain wheel (11).

5 - The system as claimed in claims 1 to 4 characterised in that the levers (06) attached to the ends of the fixed axle (05) transmit their movement by means of the rack (07) to the two gears (10) placed one on each side of the block, functioning by the free wheel system and which are attached in their ends to the rotative axle (09).

6 - The system as claimed in claim 1 to 5 characterised in that a chain wheel (11) is also attached to the rotative axle (09), the chain wheel receiving the movement from the axle and transmiting it through, a reinforced chain (13) to the other chain wheel (12) having an lower or equal diameter than the wheel (11) and which is placed in the end of the left side conventional chain wheel axle from where the conventional cranks and pedals were suppressed.

7 - The system as claimed in claims 1 to 6 characterised in that in the inside part of the metallic block (04) are installed two small racks (14) connected to the levers (06) by means of the axle sleeves (15), which by means of a crown wheel (16) positioned in the centre of the block transmit the synchronised and reciprocated movements from the levers (06) and at the same time offers them full stability.