GB2439155A

GB2439155A - Cycle with multi-stage transmission

Info

Publication number: GB2439155A
Application number: GB0613514A
Authority: GB
Inventors: Stephen Kirk-Newstead; Dawn Kirk-Newstead; Dexter Kirk-Newstead; Blaise Kirk-Newstead; Ryder Kirk-Newstead
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-07-07
Filing date: 2006-07-07
Publication date: 2007-12-19
Anticipated expiration: 2026-07-07
Also published as: GB2439155B; GB0613514D0

Abstract

The cycle transmission has the driving force applied to the pedals 108 transmitted to the rear wheel 110 via three independent drive transmission loops in series. The forward most drive transmission loop from the pedals 108 is a ribbed belt 100 with toothed pulleys 103, 104, the subsequent drive transmission loops being chains 101, 102 with wheels 105-7, 109. The belt and chain drives have adjacent end pulleys/wheels on the same axles so as to provide coupled transmission of the applied driving force. Appropriate adjustable mountings are provided for these axles enabling convenient adjustment of belt and chain tension. The rearmost wheel 109 and an intermediate wheel 107 have plural rings for gear ratio variation. A frame 119, with a rear pivoting section, has two parallel rectangular cross-section elongate members defining a channel for adjustable location of the transmission. A slidably adjustable seat has a movable rear portion with back and head rests and an upwardly extending front portion of impact absorbing material with a tunnel profile to accept adjustment of a narrower front part of the rear portion.

Description

CYCLE APPARATUS

FIeld of the Invention

The present invention relates to a cycle and in particular, although not exclusively, to a cycle comprising a drive transmission divided into a plurality of independent drive transmission loops.

Background to the Invention

The drive transmission used on most cycles comprises a single chain extending around one or more front chain rings and a rear chain ring or chain ring cassette mounted on the hub of the cycle's rear wheel. A rider drives the cycle forward by applying a force to pedals connected to the front chain ring.

Typically, where the cycle comprises a number of different sized front and rear chain rings, a rider is capable of selecting the appropriate chain ring over which the chain will run, via appropriate gear shifting apparatus in the form of front and rear derailleur mechanisms controlled by handlebar mounted gear shifters. Known front and rear chain derailleur mechanisms are spring biased such that in order to ensure correct gear indexing the drive chain must be maintained at the correct tension.

Recumbent bicycles use the same drive chain technology as conventional cycles however the frame design differs significantly so as to provide the rider with a relatively low, reclined seating position which considerably reduces aerodynamic drag during cycling. A typical recumbent cycle is disclosed in WO 0115965. To enable the rider to adopt the reclined seating position whilst still operating the drive transmission, the front chain ring and pedals are displaced forward, in this example, over the front wheel, forward of the handle bars.

Accordingly, such recumbent cycles require significantly longer chains which in turn óreates a number of problems with the drive transmission.

Chain movement, bounce or jump is a significant problem with long chains as it becomes increasingly more difficult to create and maintain the appropriate tension in the chain with increased chain length. Uncontrolled chain movement is often encountered and significantly reduces performance of the gearing system.

At worst, the chain may even completely derail off the chain nngs. A number of different approaches have been proposed in an attempt to address the problems with chain tension inherent with the use of long chains. The cycles disclosed in AU2002325735 and the recumbent Jett Creekr cycle by Burley Design Cooperative, Oregon, USA, both utilize a tensioning wheel positioned midway between the front and rear chain rings over which the chain runs so as to reduce the length of free, unsupported chain. An alternative to these tensioning pulleys is utilised by HP Velotechnik of Kriftel, Germany on their Sprint recumbent whereby the long chain, between the front and rear chain rings, runs through plastic sheaths mounted on the frame.

The use of such additional chain tensioning devices, in form of pulley wheels or plastic sheaths increases friction within the drive transmission in turn increasing the resistance experienced by a rider when driving the cycle forward via the pedals. Moreover, these sheaths or chain tubes create unacceptable noise levels as the chain runs through and contacts the inner tubular surfaces.

DE 10319832 discloses transmission apparatus for a recumbent cycle comprising a forward chain extending around a front chain ring and a rear chain extending around a chain ring mounted at the rear wheel. The independent front and rear chains are coupled in the region of the cycle seat via intermediate chain rings such that translational movement of both chains is coupled allowing the driving force to be transmitted from the pedals to the rear wheel.

GB2361513 also discloses the use of a plurality of chain drives connecting the pedal crank to the rear wheel. A first chain ring runs from the pedal crank to a gearbox input whilst a second chain ring runs from a gearbox output to a free running sprocket cluster on the pedal crank. A third chain ring connects the sprocket cluster to the rear wheel.

The inventors have realised a number of significant disadvantages associated with the drive transmission apparatus of DE 10319832. The length of the rear and in particular the front chain would cause unacceptable chain movement which would in turn prevent this type of drive transmission operating correctly with any gearing systems. Moreover, the lack of adjustability of the drive transmission of DE 10319832 would also present significant problems as the components become worn following use.

A further problem with known recumbent cycles is the proximity of the pedals to the front wheel commonly known as heel-toe interference. As a rider turns the front wheel, the rear section of the wheel is rotated from underneath to outside the frame into close proximity to the pedals. This raises significant safety concerns as a common accident with recumbent cycles involves a rider's foot clipping the front wheel during turning. This problem of heel-toe interference originates from the rider's seating position and accordingly the configuration of the drive transmission.

What is required therefore is a cycle and in particular drive transmission apparatus for a cycle that addresses the above problems.

Summary of the Invention

The inventors provide a cycle and drive transmission apparatus for a cycle, the drive transmission being dMded Into a plurality of independent but coupled drive loops. These drive loops may be formed as belt drives and/or conventional chains found within the cycle and motorcycle fields. The split drive transmission apparatus of the present invention enabled powerful, smooth, quiet and reliable transmission from a pedal driven front drive wheel through to a chain ring or chain ring cassette mounted at the hub of a rear wheel of the cycle.

The present invention utilises a novel frame design which enables a rider, seated in a recumbent-style seating position, to turn the pedals without risk of contacting the rear section of the front wheel. Additionally, the frame design allows the front drive wheel to be mounted a greater distance from the ground relative to conventional cycles which in turn allows the cycle and rider to corner more safely without risk of catching a pedal on the ground during drive transmission.

The cycle of the present invention, due to the frame design and position of the front drive wheel relative to the ground, is capable of being leant over at an angle, in the region of approximately 5 0 without the pedals touching the ground during rotation of the drive wheel. Conventional road or mountain bike cycles may only be leant over approximately 28 from vertical before the pedals are brought into contact with the ground during rotation of the front chain ring.

According to a first aspect of the present invention there is provided a cyde comprising: a first drive transmission loop extending around a first drive wheel is and a second drive wheel, said first drive transmission loop positioned forward on said cycle; a second drive transmission loop extending around a third drive wheel and a fourth drive wheel, said third drive wheel rotatably coupled to said second drive wheel; and a third drive transmission loop extending around a fifth drive wheel and a sixth drive wheel, said fifth drive wheel rotatably coupled to said fourth drive wheel wherein said third drive transmission loop is positioned rearward on said cycle and said second drive transmission loop is positioned between said first and third drive transmission loops along a length of said cycle.

The drive transmission of the present invention provides means for transmitting a driving force from a forward region of the cycle to a rearward region and in particular a rear wheel. As the drive transmission apparatus is preferably configured for use with a recumbent style riding position, the multiple drive loops of the present invention are configured to transmit the driving force, applied via the front drive wheel, located towards the front of the cycle frame, to the rear wheel. This configuration obviates the requirement for excessively long drive chains and the like.

Preferably, the first drive transmission loop is a belt drive which unlike conventional chains is operable without lubricating oil thereby eliminating oil damage to a rider's clothing.

s Preferably, the second and third drive transmission loops are chains whereby the first and second drive wheels are pulleys comprising teeth configured to engage with ribs formed on the inner working surface of the belt drive. Preferably, the third, fourth, fifth and sixth drive wheels are toothed chain rings.

Preferably, the second and third drive wheels are mounted on a first axle and the fourth and fifth drive wheels are mounted on a second axle.

Preferably, the cycle and in particular drive transmission apparatus of the present invention further comprises a first mount capable of mounting the first drive wheel at the cycle, the first mount comprising means to allow adjustable positioning of the first drive wheel at the cycle. Preferably, the cycle and drive transmission further comprises a second mount capable of mounting the second and third drive wheels at the cycle, the second mount comprising means to allow adjustable positioning of the second and third drive wheels at the cycle.

Preferably, the cycle and drive transmission apparatus further comprises a third mount capable of mounting the fourth and fifth drive wheels at the cycle, the third mount comprising means to allow adjustable positioning of the fourth and fifth drive wheels at the cycle.

The cycle of the present invention comprises a twinlsplit frame design, the frame comprising two opposed side walls extending substantially along the length of the frame, the side walls defining a channel wherein a portion of the first, second, third, fourth and/or fifth drive wheels are mounted within the channel whereby a portion of the first and second drive transmission loops extend between the side walls. This twin sided frame enables all transmission components to be safely housed inside the channel between the frame side walls thereby shielding the rider from the moving transmission components. The twin frame design further provides advantages to the cycle steering mechanism due to the support provided for the front forks extending over a much greater distance relative to prior art frame designs. The present invention therefore avoids the need for long handlebar arrangements in which the handlebars are unsupported over a large distance as is common with known recumbent cycles.

Preferably, the cycle compnses a seat dMded into a front portion and a rear portion, the rear portion being slidably moveable relative to the front portion.

Preferably, a base section of the rear portion of the seat narrows along its length allowing a part of the base, and accordingly the rear seat portion, to slide forward, for example 100 mm, through the front portion of the seat. The front portion of the seat is preferably curved upwardly such that the front and rear seat portions define a cradle or saddle arrangement offering greater comfort for the rider. The rear portion of the seat comprise a backrest and headrest offering total back support. Preferably the headrest is adjustable to restrict any whiplash effect. Preferably, the front and rear portions of the seat are made from soft, padded material giving comfort and extra cushioning for the open leg and groin areas of a rider. The front portion of the seat also encases part of the transmission components including drive wheels and chains.

Preferably, the cycle further comprises a drive transmission cover positioned adjacent to the front portion of the seat, the drive transmission cover providing a shield for a portion of the second and third drive wheels and a portion of the first and second drive loops.

By utilising at least three independent but coupled drive transmission loops mounted at the cycle frame via adjustable mount means, the tension in the belt and chain drives is fully adjustable. The drive transmission of the present invention is therefore fully functional and compatible with existing cycle gearing comprising multiple sprockets, front and rear derailleur mechanisms and frame or handlebar mounted gear shifters. Alternatively, the drive transmission components of the present invention may be mounted at the cycle frame via adjustable and/or fixed mountings.

According to a second aspect of the present invention there is provided a first drive transmission loop extending around a first drive wheel and a second drive wheel, said first drive transmission loop capable of being positioned forward on a cycle; a second drive transmission loop extending around a third drive wheel and a fourth drive wheel, said third drive wheel rotatably coupled to said second drive wheel; and a third drive transmission loop extending around a fifth drive wheel and a sixth drive wheel, said fifth drive wheel rotatably coupled to said fourth drive wheel wherein said third drive transmission loop is capable of being positioned rearward on said cycle and said second drive transmission loop is capable of being positioned between said first and third drive transmission loops along a length of said cycle.

Brief Descrj tjon of the Drawings For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to the accompanying drawings in which: Figure 1 herein is a side elevation view of the cycle according to a specific implementation of the present invention comprising three independent drive transmission loops; Figure 2A herein is a front elevation view of the cycle of figure 1 herein; Figure 2B herein is a rear elevation view of the cycle of figure 1 herein; Figure 3 herein is a plan view of the drive transmission apparatus of the cycle of figure 1 herein; Figure 4 herein is a plan view of a slightly modified version of the drive transmission of the cycle of figure 1 herein; Figure 5 herein is a an exploded view of the second and third drive wheels and mounting of the cycle of figure 1 herein; Figure 6 herein is a side elevation view of a part of the drive transmission of the cycle of figure 1 herein; Figure 7 herein is a side elevation view of the seat of the cycle of figure 1 herein; Figure 8A herein is a front elevation view of the seat of figure 7 herein; Figure 8B herein is a plan view of the seat of figure 7A herein; Figure 9A herein is a plan view of a portion of the seat of figure 7 herein; Figure 98 herein is a plan view of a portion of the seat of figure 7 herein;

Detailed Description

There will now be described by way of example a specific mode contemplated by the inventors. In the following description numerous specific details are set forth in order to provide a thorough understanding. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to

unnecessarily obscure the description.

Figure 1 herein illustrates a side elevation view, figure 2A herein illustrates a front elevation view and figure 2B herein illustrates a rear elevation view of the cycle of the present invention comprising a plurality of independent and coupled drive transmission loops. The cycle comprises a drive transmission having a first drive transmission loop 100 in the form of a ribbed belt and second and third dnve transmission loops being chains 101, 102, respectively. The belt drive component of the drive transmission is positioned forward most of the three drive loops towards the front wheel of the cycle 116. The third drive loop is positioned towards a rear wheel of the cycle 110 with the second drive loop positioned intermediate between the first and third drive loops.

Belt 100 extends around a first drive pulley 103 and a second drive pulley 104, both pulleys comprising grooves or teeth at an outer surface configured to interface with the ribs formed on belt 100. The interaction between the pulley teeth and belt ribs serves to reduce or eliminate belt-pulley wheel slip during transmission.

The first pulley 103 comprises pedal arms 115 extending radially from a central point. Pedals 108 are positioned at the outermost ends of pedal arms allowing a rider of the cycle to create a rotational force in pulley 103 via the rider's feet and legs.

Chain 101 extends around chain ring 105 positioned adjacent and being rotatably coupled to belt drive pulley 104. Drive pulley 104 and chain ring 105 are positioned rearward of front pulley wheel 103 between pulley wheel 103 and rear wheel 110. Chain 101 also extends around a second chain ring 106 mounted on the frame of the cycle at a position towards rear wheel 110 relative to chain ring 105. Chain 102 corresponding to the third drive transmission loop extends around drive wheel 107 mounted adjacent and rotatably coupled to chain ring 106 associated with the second drive transmission loop (chain 101). Chain 102 also extends around a further and sixth drive wheel 109 mounted at the hub (not shown) of rear wheel 110. Wheel 110 is mounted at the cycle via frame section 118, frame 118 being pivotally mounted at main frame 119 via pivot points 121.

A typical suspension unit found in the art, in the form of a shock absorbing piston 122 is mounted between rear frame section 118 and a frame extension 120 extending from main frame 119. Rear wheel 110 and frame section 118 are therefore capable of movement about pivot points 121, this movement being dampened by shock absorber 122.

Front wheel forks 112 are mounted at main frame 119 via first fork mountings 113 and second fork mountings 114. Fork mountings 113, 114 are separated by a distance sufficient to significantly reduce or avoid lateral movement and flex of fork 112. Handlebars 117 are mounted at an opposite end of fork 112 relative to front wheel 116.

Seat 111 is mounted at frame extension 120 to provide a seating position for the rider of the cycle.

Figure 3 herein is a plan view of a middle and rear part of the cycle of figures 1 to 2B herein. Cycle frame 119 extends from a region behind front wheel 116 to a region below seat 111. This main frame section is formed by elongate members comprising a substantially rectangular cross section. From a plan perspective, the frame is divided into two halves, each half being formed by one or more of the elongate members. The elongate members of both halves are aligned parallel to one another along the length of the frame whereby a channel is defined by the inner facing and opposed side walls of the elongate members.

According to the present invention, the twin frame design allows all or a portion of the drive transmission components to be adjustably mounted and housed within this channel formed longitudinally along the length of main frame 119.

Referring to figure 3 herein the front portion of main frame 119 positioned behind the front wheel 116 is formed by elongate members 306 aligned parallel to one another, members 306 providing support for fork mountings 113, 114.

The rearmost section of main frame 119 is defined by elongate members 305 which are respectively connected to elongate members 306 and project rearwardly from forks 112 towards a region below seat 111. According to the specific implementation of the present invention the width of the channel defined by elongate frame members 305 is substantially uniform along the length of main frame 119. The width of the channel increases at region 304 as each parallel aligned elongate member extends outwardly over a relatively short region. The pivotally mounted rear frame section 118 is defined by parallel aligned elongate members 303 which extend between a region below seat 111 to the hub of rear wheel 110. The width of the channel defined by elongate members 303 is greater than the width of the channel defined by elongate members 305, 306.

Rear frame section 118 is capable of pivoting about pivot points 121 positioned at the junction between rear frame section 118 and main frame 119.

Front pulley wheel 103 is mounted between elongate members 306 via axle 307 extending centrally through pulley wheel 103. Second pulley wheel 104 and first chain ring 105 are rotatably mounted on common axle 308 positioned between elongate members 305. Belt 100 extends over and around both rotatably mounted pulley wheels 103, 104.

Second chain ring 106 is rotatably mounted at axle 309 extending between elongate members 305 towards the rearmost section of main frame 119.

According to the specific implementation of the present invention fifth drive wheel 107 is divided into a plurality of chain rings 301, 302 both being rotatably mounted on axle 309. Chain 101 extends between and over first chain ring 105 and second chain ring 106.

The rearmost drive wheel 109, according to the specific implementation of the present invention, is divided into a plurality of independent chain rings 300 mounted at a hub (not shown) of rear wheel 110, in the form of a rear chain ring cassette as found in the art. Accordingly, the plurality of chain rings 300 are rotatably coupled to wheel 110 in at least one direction of rotation. Chain 102 extends between and over chain rings 301 or 302 and any one of the chain rings of rear cassette 300.

Figure 4 herein illustrates a plan view of the forward portion of the cycle drive transmission apparatus of figures 1 to 3 herein between the region of fork mounting 113 and the rearmost portion of main frame 119 immediately behind axle 309. Axle 307 that supports second pulley wheel 104 and first chain ring is mounted at frame 119 via an adjustable mounting 402. Axle 309 rotatably mounting second chain ring 106 and chain rings 301, 302 is mounted at frame 119 via adjustable mounting 403.

According to a slight variation on the specific implementation of the present invention a guide pulley 400 is positioned intermediate between first chain ring and second chain ring 106. Guide pulley 400 is rotatably mounted on axle 401 which in turn is mounted at an adjustable mount. Chain 101 extends over and in contact with tensioning pulley 400 serving to decrease the amount of unsupported chain between first and second chain rings 105, 106 respectively.

According to further specific implementations of the present invention a plurality of additional tensioning pulley wheels 400 may be mounted at frame 119, 118 to assist with obtaining the appropriate chain tension. Alternatively, the present invention is operable without any additional tensioning pulley wheels.

According to known cycle and motorcycle technology, fork mounting 113/114 is pivotally mounted to fork arm holder 405. Holder 405 is pivotally mounted at a substantially central position 406 of mount 113/114 whereby a rider turning handlebars 1 17 is capable of rotating holder 405 and according wheel 116 relative to the axis of rotation 406. Holder 405 comprises circular fork arm receiving sections 407 through which each fork arm is threaded.

Figure 5 herein illustrates an exploded perspective view of drive wheel mount 402 and drive wheels 104, 105. Drive mount 402 is divided into two halves, each half being independently and respectively mounted at the innermost side wall of main frame 119 and in particular elongate frame members 305. Each half of the mount comprises two slightly curved elongate cut-out sections 501 extending substantially from top to bottom of each mount 402. Cut-out sections 501 are configured to receive securing pins, bolts or screws capable of securing mount 402 to the side wall of frame member 305. Each mount further comprises a substantially circular cut-out section 502 configured to receive and mount axle 308. Axle 308 provides a rotatable mounting for pulley wheel 104 and chain ring 105. Suitable spaces/washers 500 are provided and positioned coaxially with axle 308.

Through the provision of elongate cut-out sections 501, mounts 402 are capable of being moveably positioned about securing pins 404. Mount 402 further comprises a second circular cut-out section 503 capable of receiving and mounting axle 401 comprising chain tensioning wheel 400 according to further specific implementations of the present invention.

Figure 6 herein illustrates a side elevation view of main frame 119 and selected components of the cycle and drive transmission apparatus of figures 1 to 5 herein. Frontmost pulley wheel 103 is mounted in the channel formed by the twin frame 119 via mounting 600. Mounting 600 provides a means for mounting axle 307 at the respective elongate frame members 306. Mount 600 is secured to mounting bracket 602 using suitable mounting screws or pins 601. Mounting bracket 602 is in turn releasably and adjustably secured to each of the elongate frame members 306 via suitable securing screws or pins 603. By adjustment of the securing screws or pins 601, 603 and positional adjustment of mounting 600/602 front pulley wheel 103 is moveable in a direction substantially parallel to elongate frame members 306 and the substantially parallel aligned forks 112 as indicated by arrows 611 and 612. Accordingly, the tension in belt 100 may be adjusted by the positional adjustment of pulley wheel 103 at mount 600/602.

So as to mount the first drive wheel between elongate members 306, a split crank design is utilised. The front drive wheel, rotatably mounted on axle 307 is locked in position via a lock ring (not shown). Bearings (not shown) are positioned either side of the drive wheel with annular spaces (not shown) positioned either side of the bearings between the drive wheel and mountings 600. The crank therefore is formed into respective halves either side of the front drive wheel save for the single axle 307 extending between each mount 600, through the spaces, bearings and drive wheel.

In addition or alternatively, the tension in belt 100 may be adjusted through the positional adjustment of second pulley wheel 104 mounted at frame 119 via twin mount 402. The desired belt tension is achieved by unscrewing mount locating screws 404 slightly and sliding the entire mount assembly 402, and drive wheels 104 and 105 relative to the mount screws 404. Mount 402 and wheels 104, 105 are thereby moveable in the direction 608, 609 relative to frame 119.

Accordingly, through displacement of mount 402 in directions 608, 609 the tension in chain 101 may be selectively adjusted.

Axle 309, rotatably mounting chain rings 106, 301, 302 is adjustably mounted at the rearmost section of frame 119 towards rear wheel 110 via mounting 403 mounted at a portion of the inner opposed surfaces of elongate members 305. Mounting 403 is secured to each frame member by mounting screws 610. By adjusting the screws 610 and moving mount 403, chain rings 106, 301, 302 may be displaced in directions 613, 614 to affect the tension of chain 101 and chain 102, with reference to figures 1 and 3 herein.

Through the provision of adjustable mountings 600, 602, 402 and 403 the tension in each of the independent drive transmission loops 100, 101, 102 may be adjusted by the desired amount. This functionality is particularly advantages when the cycle is first assembled in order to achieve the correct tension in the belt and chain drives and correct for any minor engineering/construction imperfections. Secondly, the drive transmission adjustability further enables the correct belt and chain tensions to be maintained during use of the cycle and corresponding component wear. As front elongate frame members 306 are aligned transverse to the

length of elongate frame members 305 (at an angle between 80 to 110 ) frame strengthening supports 606 are provided at the angle between each respective elongate member 306 and 305. Further frame strengthening supports 605 are provided between elongate frame members 305 and frame extensions 120 which extend transverse to the length of each elongate member 305.

Figure 7 herein illustrates a side elevation view of seat 111 of the cycle of figures 1 to 2B. Seat 111 comprises seat frame 701 extending from a seating region 702 through a backrest region 703 to a headrest region 704. Backrest portion 703 is inclined upwardly and extends from base portion 702 supported by frame 701. Headrest 704 is positioned above backrest 703 and is also supported by frame 701. Frame 701 extends underneath base 702 in contact with seat mount 705 located directly underneath base 702. Mount 705 comprises a plurality of elongate slots 706 formed at its lower region. Seat 111 via mount 705 is adjustably secured to the frame of the cycle (via frame extension 120 of figure 1 herein) by securing screws 707. One securing screw is provided per elongate slot such that when screws 707 are not fully tightened seat 111 is capable of sliding back and forth in directions 708, 709 as screws 707 slide within elongate slots 706.

Seat 111 comprising moveable rear portion 701-706 further comprises front portion 700. The front seat portion is formed as a tunnel being defined by tunnel walls 700 which extend forward from seat base 702. An uppermost surface of seat front portion is curved and inclined upwardly from seat base 702.

Seat base 702, backrest 703, headrest 704 and the upwardly inclined surface 700 of the front seat portion comprise an impact absorbing material including for example, a sponge/foam material or the like.

Ajoined at front most edge 712 of hollow front seat portion 700/710 the cycle further comprises a drive transmission cover having side walls 711 defining internal hollow chamber 713. Cover 711 is capable of positioning over and about drive wheels 104, 105, mounting 402 and a portion of first and second drive loops 100, 101. Further, second drive loop 101 extends through hollow tunnel 710 defined by seat walls 700. As the majority of the drive transmission components are located within the channel formed by the parallel aligned elongate frame members 119 in addition to being partially housed by cover 7111713 and hollow front seat portion 7001710 the majority of the drive transmission apparatus of the present invention is concealed thereby reducing the risk of a rider accidentally contacting the moving components of the drive transmission.

Figure 8A herein is a front elevation view and figure 8B herein is a plan view of the seat and cover of figure 7 herein. Figures 9A and 9B herein are plan views of seat base 702 and seat front portion 700. Seat base 702 comprises a cross section that decreases along its length in the direction from backrest 703 towards seat front portion 700/710. In particular, seat base 702 comprises a front neck portion 800 comprising a uniform, reduced cross section relative to a rear portion.

Neck 800 is capable of sliding into and out of tunnel 710, indicated by arrow 803.

As detailed with reference to figure 7 herein the rear portion of seat 111 comprising base portion 702, backrest 703 and headrest 704 is configured to slide backwards and forwards relative to seat front portion 700/710, in directions 803 and 900. Frame 701, in a region above headrest 704 is formed as a curved handle 802 of sufficient size to enable a user to grasp seat 111 during, for example, adjustment of the seat rear portion relative to the seat front portion.

Claims

Claims: 1. A cycle comprising: a first drive transmission loop

extending around a first drive wheel and a second drive wheel said first dnve whe( positioned forward of handlebars a second drive transmission loop extending around a third drive wheel and a fourth drive wheel, said third drive wheel rotatably coupled to said second drive wheel; and a third drive transmission loop extending around a fifth drive wheel and a sixth drive wheel, said fifth drive wheel rotatably coupled to said fourth drive wheel.

2. The cycle as claimed in claim 1 wherein said first drive transmission loop Is a belt.

3. The cycle as claimed in claims I or 2 wherein said second drive transmission loop is a chain.

4. The cycle as claimed in any preceding claim wherein said third drive transmission loop is a chain.

5. The cycle as claimed in any preceding claim wherein said first and second drive wheels are puleys and said third, fourth, fifth and sixth drive wheels are toothed cham rings.

6. The cycle as claimed in any preceding claim wherein said second and third drive wheels are mounted on a first axle.

7. The cycle as claimed in any preceding claim wherein said fourth and fifth drive wheels are mounted on a second axle.

8. The cycle as claimed in any preceding claim further comprising a first mount capable of mounting said first drive wheel at said cyde, said first mount comprising means to allow adjustable positioning of said first drive wheel atsaidcycle.

9. The cycle as claimed in any preceding claim further comprising a second mount capable of mounting said second and third drive wheels at said cyde, said second mount comprising means to allow adjustable positioning of said second and third drive wheels at said cycle.

10. The cycle as claimed in any preceding claim further comprising a third mount capable of mounting said fourth and fifth drive wheels at said cycle, said third mount comprising means to allow adjustable positioning of said fourth and fifth drive wheels at said cycle.

11. The cycle as claimed in any preceding claim wherein said fifth drive wheel is dMded into a plurality of chain rings, said third drive transmission loop capable of extending around any one of said plurality of chain rings.

12. The cycle as claimed in any preceding claim wherein said sixth drive wheel is divided into a plurality of chain rings, said third drive transmission loop capable of extending around any one of said plurality of chain rings.

13. The cycle as claimed in any preceding claim further comprising first and second pedals connected to said first drive wheel via first and second crank arms wherein said first drive transmission loop is capable of being driven by a : ... force applied to said first and second pedals. * *

14. The cycle as claimed in any preceding claim wherein said sbcth drive wheel is rotatably coupled to a tear wheel of said cycle, said rear wheel * * capable of rotating in contact with the ground. * ** * * * *** * * *

15. The cycle as claimed in any preceding claim further compnsuIg a frame, said frame comprising twe opposed side wells extending substantially along the length of said frame, said side walls defining a channel wherein a portion of said first, second, third, fourth and/or fifth drive wheels are mounted within said channel whereby a portion of said first and second drive transmission loops extend between said side walls 18. The cycle as claimed in claim 15 wherein a portion of said fist and second drive transmission ioops and said first, second, third, fourth and/or fifth drive wheels are concealed by said side waDs of said frame.

17. The cycle as dainied in any preceding claim further comprising a seat having a front portion and a rear portion, said rear portion being moveable relative to said front portion.

18. The cycle as claimed in claim 17 wherein said rear portion of said seat is slidably moveable relative to said front portion of said seat.

19. The cycle as daimed in claims 17 or 18 wherein said front portion of said aeatishollowwherebysaici rearportlon ofsaidseatiscapableofsljding into said hollow front portion. 20.

rear portion of said seat comprises a backrest capable of supporting the back of a rider.

21. The cycle as claimed in claim 20 wherein said rear portion of said * seat comprises a base section positioned transverse to said backrest wherein a cross sectional area of said base decreases along its length away from said S.. * **

SI I *1S *

I S.. *

22. The cycle as dalmed in claIms 20 or 21 wherein said backrest further comprises a headiest capable of supporting the head of a rider. 23.

front portion of said seat comprises an impact absorbing materiaL 24. The cycle as claimed in any one of claims 21 to 23 wherein a part of said front portion of said seat is indned upwardly away from said base section of said seat and a cross sectional area of said front portion of said seat is less than a cross sectional area of said rear portion of said seat.

25. The cycle as claimed in any one claims 17 to 24 further comprising a drive transmission cover positioned adjacent said front portion of said seat, said cover defining a cavity capable of housing a portion of said second and third drive wheels and a portion of said first and second drive loops, whereby a portion of saidsondandthirddriewelsandaporofsaidfianddd loops are concealed by said cover.

26. Cycle drive transmission apparatus comprising: a first drive transmission loop extending around a first drive wheel and a second drive wheel; a second drive transmission loop extending around a third drive wheel and a fourth drive wheel, said third drive wheel rotatably coupled to said second drive wheel; and S. a third drive transmission loop extending around a fifth drive wheel and a sixth drive wheel, said fifth drive wheel rotatably coupled to said fourth drive wheel. S.. * S. * . . ** S *SS

27. The apparatus as claimed in claim 26 wherein said fiist drive transmission loop Is a belt.

28. The apparatus as claimed in claim 27 wherein said first and second drive wheels are pulleys.

29. The apparatus as claimed in any one of claims 26 to 28 wherein said second drive transmission loop is a chain.

30. The apparatus as claimed m claim 29 wherein said third and fourth drive wheels are toothed chain rings.

31. The apparatus as claimed in any one of claims 26 to 30 wherein said third drive transmission loop is a chain.

32. The apparatus as claimed in claim 31 wherein said fifth and sixth drive wheels are toothed chain rings.

33. The apparatus as daWned in any one daWns 26 to 32 wherein said first drive wheel comprises first and second pedal arms connected to first and second pedals wherein said first drive wheel is rotatdble in response to a force applied to said first and second pedals.

34. The apparatus as claimed in claim 33 wherein said sixth drive wheel is capable of being rotatably coupled to a rear wheel of said cycle, said rear wheel configured for rotation over the ground.

35. The apparatus as claimed in any one of claims 26 to 34 wherein said second and third drive wheels are mounted on a first axle and said fourth and fifth drive wheels are mounted on a second axle. S. * *.*

S I.. * *5 *. S *5S S

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Amendments to the claims have been filed as follows Claims: 1. A cycle comprising: a first drive transmission loop extending around a first drive wheel and a second drive wheel, said first drive transmission loop positioned forward on said cycle; a second drive transmission loop extending around a third drive wheel and a fourth drive wheel, said third drive wheel rotatably coupled to said second drive wheel; and a third drive transmission loop extending around a fifth drive wheel and a sixth dnve wheel, said fifth drive wheel rotatably coupled to said fourth drive wheel wherein said third drive transmission loop is positioned rearward on said cycle and said second drive transmission loop is positioned between said first and third drive transmission loops along a length of said cycle. b

2. The cycle as claimed in claim I wherein said first drive transmission loop is a belt.

3. The cycle as claimed in claims I or 2 wherein said second drive transmission loop is a chain.

4. The cycle as daimed in any preceding claim wherein said third drive transmission loop is a chain. I. * . p...

5. The cycle as claimed in any preceding claim wherein said first and second drive wheels are pulleys and said third, fourth, fifth and sixth drive wheels * : are toothed chain rings. * 30

6. The cycle as claimed in any preceding claim wherein said second and third drive wheels are mounted on a first axle.

7. The cycle as claimed in any preceding daim wherein said fourth and fifth drive wheels are mounted on a second axle.

8. The cycle as claimed in any preceding claim further comprising a first mount capable of mounting said first drive wheel at said cycle, said first mount comprising means to allow adjustable positioning of said first drive wheel at said cycle.

9. The cycle as claimed in any preceding daim further comprising a second mount capable of mounting said second and third drive wheels at said cycle, said second mount comprising means to allow adjustable positioning of said second and third drive wheels at said cycle.

10. The cycle as daimed in any preceding daim further comprising a is third mount capable of mounting said fourth and fifth drive wheels at said cycle, said third mount comprising means to allow adjustable positioning of said fouth and fifth drive wheels at said cyde.

11. The cycle as claimed in any preceding daim wherein said fifth drive wheel is dMded into a plurality of chain rings, said third drive transmission loop capable of extending around any one of said plurality of chain rings.

12. The cycle as claimed in any preceding claim wherein said sixth drive wheel is divided into a plurality of chain rings, said third drive transmission loop capable of extending around any one of said plurality of chain rings. *. * * * ***

13. The cycle as claimed in any preceding claim further comprising first and second pedals connected to said first drive wheel via first and second crank * : arms wherein said first drive transmission loop is capable of being driven by a * 30 force applied to said first and second pedals. * ** * * * * S. S. * 2q.

14. The cycle as claimed in any preceding claim wherein said sixth drive wheel is rotatably coupled to a rear wheel of said cycle, said rear wheel capable of rotating in contact with the ground.

15. The cycle as claimed in any preceding daim further comprising a frame, said frame comprising two opposed side walls extending substantially along the length of said frame, said side walls defining a channel wherein a portion of said first, second, third, fourth and/or fifth drive wheels are mounted within said channel whereby a portion of said first and second drive transmission loops extend between said side walls.

16. The cycle as claimed in claim 15 wherein a portion of said first and second drive transmission loops and said first, second, third, fourth and/or fifth drive wheels are concealed by said side walls of said frame.

17. The cyde as claimed in any preceding claim further comprising a seat having a front portion and a rear portion, said rear portion being moveable relative to said front portion.

18. The cycle as claimed in claim 17 wherein said rear portion of said seat is slidably moveable relative to said front portion of said seat.

19. The cycle as claimed in claims 17 or 18 wherein said front portion of said seat is hollow whereby said rear portion of said seat is capable of sliding into said hollow front portion. *.

20. The cycle as claimed in any one of claims 17 to 19 wherein said * rear portion of said seat comprises a backrest capable of supporting the back of *S....

* arider.

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*:*::* 21. The cycle as claimed in claim 20 wherein said rear portion of said * seat comprises a base section positioned transverse to said backrest wherein a cross sectional area of said base decreases along its length away from said backrest.

22. The cycle as claimed in daims 20 or 21 wherein said backrest further comprises a headrest capable of supporting the head of a rider.

23. The cycle as claimed in any one of claims 17 to 22 wherein said front portion of said seat comprises an impact absorbing material.

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24. The cycle as claimed in any one of claims 21 to 23 wherein a part of said front portion of said seat is inclined upwardly away from said base section of said seat and a cross sectional area of said front portion of said seat is less than a cross sectional area of said rear portion of said seat.

25. The cycle as claimed in any one claims 17 to 24 further comprising a drive transmission cover positioned adjacent said front portion of said seat, said cover defining a cavity capable of housing a portion of said second and third drive wheels and a portion of said first and second drive loops, whereby a portion of said second and third drive wheels and a portion of said first and second drive loops are concealed by said cover.

26. Cycle drive transmission apparatus comprising: a first drive transmission loop extending around a first drive wheel and a second drive wheel, said first drive transmission loop capable of being positioned : * forward on a cycle; * *** **** * * **S* a second drive transmission loop extending around a third drive wheel and a fourth drive wheel, said third drive wheel rotatably coupled to said second drive :: 30 wheel; and * ** a third drive transmission loop extending around a fifth drive wheel and a sixth S..

drive wheel, said fifth drive wheel rotatably coupled to said fourth drive wheel wherein said third drive transmission loop is capable of being positioned rearward on said cycle and said second drive transmission loop is capable of being positioned between said first and third drive transmission loops along a length of said cycle.

27. The apparatus as claimed in claim 26 wherein said first drive transmission loop is a belt.

28. The apparatus as claimed in claim 27 wherein said first and second drive wheels are pulleys.

29. The apparatus as claimed in any one of claims 26 to 28 wherein said second drive transmission loop is a chain.

30. The apparatus as claimed in claim 29 wherein said third and fourth drive wheels are toothed chain rings.

31. The apparatus as daimed in any one of claims 26 to 30 wherein said third drive transmission loop is a chain.

32. The apparatus as claimed in claim 31 wherein said fifth and sixth drive wheels are toothed chain rings.

33. The apparatus as claimed in any one claims 26 to 32 wherein said first drive wheel comprises first and second pedal arms connected to first and second pedals wherein said first drive wheel is rotatable in response to a force applied to said first and second pedals.

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* 34. The apparatus as claimed in claim 33 wherein said sixth drive wheel is capable of being rotatably coupled to a rear wheel of said cycle, said *.. * rear wheel configured for rotation over the ground. * S. * ***

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35. The apparatus as claimed in any one of claims 26 to 34 wherein said second and third drive wheels are mounted on a first axle and said fourth and fifth drive wheels are mounted on a second axle. S. 4 *4. * ..* * S *

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