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Patent Searching and Data


Title:
CYCLE TRANSPORT SYSTEM
Document Type and Number:
WIPO Patent Application WO/2014/044994
Kind Code:
A1
Abstract:
A vehicle (10, 200, 300) comprising a frame, a front wheel and at least one rear wheel; and directly or indirectly attached to said frame, a front seat that faces forwards such that in normal use a first rider can sit thereon and to steer the vehicle as it moves forward and a rear seat for a second rider that faces backwards; having a rear rider crank assembly (42,44) and a front rider crank assembly (36) and where a wheel hub (52) and a connected rear sprocket (46), or sprocket bush (56) and a connected rear sprocket (46), are rotatably mounted around the crankshaft (42) of the rear rider crank assembly such that in use pedal power from a rear rider is first transmitted through the rear pedals (34) and rear crank assembly, via a cross-over drive chain (38), to the front rider crank assembly.

Inventors:
EJIZU EZEKIEL GEORGE (GB)
Application Number:
GB2012/000731
Publication Date:
March 27, 2014
Filing Date:
September 20, 2012
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
EJIZU EZEKIEL GEORGE (GB)
International Classes:
B62K3/00; B62K3/14; B62K7/04; B62K13/08; B62K17/00; B62K27/00; B62K27/02; B62K27/12
Domestic Patent References:
WO2009131421A22009-10-29
Foreign References:
DE3332539A11984-02-23
CH108628A1925-01-16
US20080296862A12008-12-04
GB2489476A2012-10-03
Other References:
None
Attorney, Agent or Firm:
TART, Keith R. (162 Walsall RoadFour Oaks,Sutton Coldfield, West Midlands B74 4RD, GB)
Download PDF:
Claims:
CLAIMS

1. A cycle comprising a frame, a front wheel and a rear wheel; and directly or indirectly attached to said frame, a front seat that faces forwards such that in normal use a first cyclist/rider can sit thereon and steer the cycle as it moves forward; wherein the cycle also has a rear seat that faces backwards such that in normal use a second cyclist/rider can sit on said rear seat in a generally back-to- back position or shoulders-to-back position relative to a said first cyclist/rider; having a rear rider crank assembly (42, 44) and a front rider crank assembly (36) and characterised in that: a wheel hub (52) and a connected rear sprocket (46) are rotatably mounted around the crankshaft (42) of said rear crank assembly such that in use pedal power from a rear rider is first transmitted through the rear pedals (34) and rear crank assembly (42, 44), via a cross-over drive chain (38), to said front rider crank assembly.

2. A cycle according to Claim 1 wherein in use pedal power is transmitted from said front rider crank assembly to said rear sprocket (46) by a single drive chain (40).

3. A cycle according to any preceding claim wherein said wheel hub (52) is indirectly connected to said rear sprocket (46) by a connecting sleeve (48) attached to said rear sprocket (46) and configured to engage the inside of the wheel hub (52).

4. A cycle according to any preceding claim wherein the rear seat is located between the front wheel and the rear wheel and the rear seat further comprises a backrest/support a major portion of which is located at a level lower than the front seat.

5. A cycle according to Claim 1 or 2 and a trailer wherein in use the trailer may be connected to the rear portion of said frame following detachment of said rear wheel.

6. A cycle and trailer according to Claim 5 wherein in use, following detachment of said rear wheel, the rear of the cycle may be directly or indirectly connected to the front of the trailer such that the cycle to may pivot relative to the trailer.

7. A cycle and trailer according to Claim 5 wherein in use, following detachment of said rear wheel, the rear of the cycle may be directly or indirectly connected to the front of the trailer such that the cycle may pivot about the longitudinal axis of said axle of the trailer.

8. A cycle and trailer according to any of Claims 5 to 7 wherein the trailer comprises a pair of front wheels located on a front axle and a pair of rear wheels mounted on a rear axle.

9. A cycle and trailer according to Claim 8 wherein the front and rear wheels on a first side of the trailer are connected by a continuous track and the front and rear wheels on the other (second) side of the trailer are also connected by a continuous track.

10. A cycle according to any of Claims 1 to 4 and a trailer that may be attached to the rear of said cycle.

1 1 . A cycle and trailer according to Claim 6 wherein in use the wheel stays of the cycle are connected to the trailer via one or more connecting member(s).

12. A cycle and trailer according to Claim 11 wherein in use the connecting member(s) is pivotally mounted to the front axle of the trailer and locked to the cycle wheel stays by a tubular member(s) connected to a trailer handle.

13. A cycle and trailer according to Claim 12 wherein the tubular member is "U- shaped" and the open ends engage an open tubular portion(s) of the connecting member and an open tubular portion(s) of a cycle wheel stay.

14. A cycle and trailer according to any of Claims 1 1 to 13 comprising two wheel stays pivotally mounted to the rear portion of cycle frame so as to facilitate removal of the cycle rear wheel prior to connecting a trailer.

15. A cycle and trailer according to any preceding claim wherein the cycle frame has at least one pivotally mounted sidebar that in use the rear cyclist/rider may hold.

16. A cycle and trailer according to Claim 5 wherein in use, following detachment of said rear wheel and the hub (52) thereof they may be replaced by a sprocket bush (56) having a rear sprocket (62).

17. A vehicle comprising a frame, a front wheel and at least one rear wheel; and directly or indirectly attached to said frame, a front seat that faces forwards allowing a first rider to sit thereon and steer the vehicle as it moves forward; and a rear seat that faces backwards such that in normal use a second rider can sit on said rear seat in a generally back-to-back position relative to a said first rider; further comprising a rear rider crank assembly (42, 44) and a front rider crank assembly (36); and characterised in that: a wheel hub (52) and a connected rear sprocket (46); or sprocket bush (56) having a connected rear sprocket (62), are rotatably mounted around the crankshaft (42) of said rear crank assembly such that in use pedal power from a rear rider is first transmitted through the rear pedals (34) and rear crank assembly, via a cross-over drive chain (38), to said front rider crank assembly.

18. A vehicle according to Claim 17 wherein in use pedal power is transmitted from said front rider crank assembly to said rear sprocket (46, 62) by a single drive chain (40).

19. A vehicle according to Claim 17 or 18 wherein said wheel hub (52) or sprocket bush (56) are indirectly connected to said rear sprocket (46, 62) by a connecting sleeve (48, 58) attached to said rear sprocket (46, 62) and configured to engage the inside of the wheel hub (52) or sprocket bush (56).

20. A vehicle according to any of Claims 1 7 to 19 comprising a bicycle (10); a tricycle (200) or a bicycle-trailer hybrid (200, 300).

Description:
Cycle Transport System

Technical Field

The present invention relates to a motorised cycle or pedal cycle for two persons having either one or two rear wheels and, optionally to a trailer adapted for connection to the rear end thereof.

Background Art

In economically underdeveloped or Third World countries there is a frequent requirement to transport people and goods relatively long distances over often rough roads or ground, especially in poorly developed areas and agricultural regions. Bicycles are often used in such circumstances; sometimes taking the form of two-person (tandem) cycles. However, conventional bicycles cope poorly in wet and sandy soil conditions and are not well suited in any event for towing trailers.

In such areas, single-person bicycles are sometimes converted into pedal powered motors/generators; for example, by removing a rear wheel and fitting a chain drive so that a drive shaft can be turned. However, the power that can be generated by one person in such a way is quite limited.

Disclosure of Invention

The present invention seeks to overcome these problems by providing an improved pedal-powered vehicle that is especially suited to traversing rough, wet and sandy ground. Another aim of the invention is to provide a two-person vehicle, where a front rider steers the vehicle and a rear rider sits in a position that allows considerable pedal power to be exerted. The vehicle of the invention may include a detachable trailer that can be loaded with goods or supplies and which also is adapted to traverse un-tarmaced (unsurfaced) roads and paths. A preferred embodiment of the present invention also advantageously provides a vehicle with a trailer portion where the vehicle may be readily converted to a more socially acceptable tandem tricycle; in this form the vehicle provides transport means better suited for recreational purposes; typically in the evening and at weekends. The present invention also provides a vehicle that can be adapted to become a static pedal-powered machine; advantageously powered by two persons.

In one aspect the invention comprises a cycle having a frame, a front wheel and at least one rear wheel; and directly or indirectly attached to said frame, a front seat that faces forwards such that in normal use a first cyclist/rider can sit thereon and to steer the cycle as it moves forward; wherein the cycle also has a rear seat that faces backwards such that in normal use a second cyclist/rider can sit on said rear seat in a back-to-back position or shoulders-to-back position relative to a said first cyclist/rider; having a rear rider crank assembly and a front rider crank assembly and characterised in that: a wheel hub and a connected rear sprocket are rotatably mounted around the crankshaft of said rear crank assembly such that in use pedal power from a rear rider is first transmitted through the rear pedals and rear crank assembly, via a cross-over drive chain, to said front rider crank assembly.

Preferably, in use pedal power is transmitted from said front rider crank assembly to said rear sprocket by a single drive chain. Preferably, said wheel hub is indirectly connected to said rear sprocket by a connecting sleeve attached to said rear sprocket and configured to engage the inside of the wheel hub. Preferably, the rear seat is located between the front wheel and the rear wheel and the rear seat further comprises a backrest/support a major portion of which is located at a level lower than the front seat.

The invention may comprise cycle as described above and a trailer that in use may be attached to the rear of said cycle. Preferably, following detachment of said rear wheel/wheels, the rear of the cycle may be directly or indirectly connected to the front of the trailer such that the cycle to may pivot relative to the trailer. Alternatively, in use following detachment of said rear wheel/wheels, the rear of the cycle may be directly or indirectly connected to the front of the trailer such that the cycle may pivot about the longitudinal axis of said axle of the trailer. Preferably, the trailer comprises a pair of front wheels located on a front axle and a pair of rear wheels mounted on a rear axle. The front and rear wheels on a first side of the trailer may be connected by a continuous track and the front and rear wheels on the other (second) side of the trailer are also connected by a continuous track.

The invention may comprise a cycle as described above and a trailer wherein in use the trailer may be connected to the rear portion of said frame following detachment of said rear wheel. Preferably, following detachment of said rear wheel and the hub thereof they may be replaced by a sprocket bush having a rear sprocket. Preferably, the wheel stays of such a cycle and trailer are connected to the trailer etc. via one or more connecting member(s). Preferably, in use the connecting member(s) is pivotally mounted to the front axle of the trailer and locked to the cycle wheel stays by a tubular member(s) connected to a trailer handle. Preferably, the tubular member is "U-shaped" and the open ends engage an open tubular portion(s) of the connecting member and an open tubular portion(s) of a cycle wheel stay. The cycle and trailer may comprise two wheel stays pivotally mounted to the rear portion of cycle frame so as to facilitate removal of the cycle rear wheel prior to connecting a trailer or other equipment; such as a drive shaft via a suitable drive chain etc.

Preferably, the cycle or cycle and trailer comprises a cycle frame having at least one pivotally mounted sidebar that in use the rear cyclist/rider may hold.

In another aspect the invention may comprise a vehicle having a frame, a front wheel and at least one rear wheel; and directly or indirectly attached to said frame, a front seat that faces forwards allowing a first rider to sit thereon and to steer the vehicle as it moves forward; and a rear seat that faces backwards such that in normal use a second rider can sit on said rear seat in a generally back-to-back position relative to a said first rider; further comprising a rear rider crank assembly and a front rider crank assembly; and characterised in that: a wheel hub and a connected rear sprocket or sprocket bush and a connected rear sprocket are rotatably mounted around the crankshaft of said rear crank assembly such that in use pedal power from a rear rider is first transmitted through the rear pedals and rear crank assembly, via a cross-over drive chain, to said front rider crank assembly. Preferably, in use pedal power ' is transmitted from said front rider crank assembly to said rear sprocket by a single drive chain. The wheel hub or sprocket bush may be indirectly connected to said rear sprocket by a connecting sleeve attached to said rear sprocket and configured to engage the inside of the wheel hub or sprocket bush. The vehicle may comprise a bicycle; a tricycle or a bicycle-trailer hybrid.

Brief Description of Drawings

The following diagrammatic figures illustrate two embodiments of the present invention;

Figure 1 shows a perspective view of a cycle according to the present invention that has a single rear wheel;

Figure 2 shows a side elevation of the cycle shown in Figure 1 with a front rider and a rear rider shown in dashed outline;

Figure 3 shows a perspective view of the cycle of Figure 1 , except with sidebars raised, during removal of the rear wheel;

Figure 4a shows the pedal, sprocket and chain system used in the cycle shown in Figure 1 ; and Figure 4b shows how the rear wheel hub engages the wheel drive sprocket;

Figure 5 shows an enlarged gear drive used, instead of a wheel hub, when a trailer is attached to cycle shown in Figure 1 ;

Figures 6 shows an alternative (to Figure 4a) pedal, and sprocket system used in the cycle shown in Figure 1 , and Figure 7 shows an alternative (to Figure 5) gear drive used when a trailer is attached;

Figure 8a shows a perspective view of the topside of a trailer adapted for attachment to the cycle of Figure 1 , and Figure 8b shows a corresponding underside view; Figure 9 shows a perspective view of the trailer of Figure 8 attached to the adapted cycle of Figure 1 ;

Figure 10 shows how the cycle and trailer are connected using a U-shaped member;

Figure 11 shows a side view of the cycle of Figure 1 in its adapted form connected to the trailer of Figure 8, going up an incline;

Figure 12 shows a perspective view of a cycle (tricycle) according to a second embodiment of the invention that has a pair of rear wheels;

Figure 13 shows a side elevation of the tricycle shown in Figure 12 with a front and rear rider shown in dashed outline;

Figure 14a shows a perspective view of the topside of a trailer adapted for attachment to the tricycle of Figure 12, and Figure 14b shows a corresponding underside view;

Figure 15 shows a perspective view of the trailer of Figure 14 attached to the tricycle of Figure 12; and

Figure 16 shows a side elevation of the tricycle of Figure 12 and the connected trailer of Figure 14 going up an incline.

Description of Preferred Embodiments

Figures 1-1 1 diagrammatically illustrate a first embodiment of a transport system according to the present invention. Figure 1 shows a perspective view of a tandem bicycle according to the invention and Figure 2 shows a side elevation of the cycle shown in Figure 1.

The cycle (10) comprises a frame (12); a conventional front wheel (14) with a wheel hub and bearing (14a) and spokes (not shown); and a single rear wheel (16) also with a hub/bearing and spokes (not shown). The front portion of the frame ( 12) is approximately triangular in configuration and comprises a top tube (12a); a head tube (12b); a down tube (12c) and a seat tube (12d) with a crankcase (12e) at its lower extremity that houses a crankshaft connected to a pair of crank-arms and front pedals (24). The head tube ( 12b) houses a conventional front fork member (12f) to which the front wheel hub/bearing (14a) is fixed; the upper part of said fork (12f) is connected via a headset ( 12g) to conventional front handlebars (12h). A front seat (18) is connected to the seat tube (12d) as in a conventional bicycle.

The rear portion of the frame (12) comprises a rear seat support assembly (20) and a pair of rear wheel stays (22). The rear seat support assembly (20) has an inverted "T-shaped" portion comprising an upper vertical tube (20a) and a horizontal rear seat support tube (20b). The top end of the vertical tube (20a) is connected to the junction of the top tube (12a) and seat tube (12d). The lower end of the vertical tube (20a) is connected to the horizontal seat tube (20b). The seat support tube (20b) may be generally "D-shaped" (in plan view) in order to facilitate support of a rear seat (26). Two mounting tubes (20c end only shown) extend vertically downward from beneath the horizontal seat tube (20b). The pair of rear wheel stays (22) are pivotally mounted to these mounting tubes (20c). The combination of the vertical tube (20a), the seat support tube (20b) and the mounting tubes (20c) provide a support assembly (20) that is generally of "wishbone" shape. The lower ends of the mounting tubes (20c) are also connected to the crankcase (12e) by a further wishbone shaped member (28). The wheel stays (22) pivot outwardly to facilitate removal of the rear wheel (16) as shown in Figure 3. Each rear wheel stay comprises an upper arm (22a) a lower arm (22b) connected at a first end to an outer pivot tube (22c) that may pivot about a mounting tube (20c). The second end of the upper and lower arms each have an open vertical tubular portion (22d, 22e) optionally used to connect a detachable trailer (see below). Each rear wheel stay also has a strengthening cross stay (22f) and a rear wheel mounting plate (22g) with a circular aperture (22h).

The rear seat (26) is located at a lower level than the front seat (18). This allows a rear seat backrest (30) to be located (at least in part) below the front seat (18) and to be supported by an inverted "U-shaped" tubular frame (32) connected to the "D-shaped" seat support tube (20b). Alternatively, the seat backrest (30) may be connected to and supported by the vertical tube (20a) portion of the support assembly (20).

The front seat (18) serves to allow a front rider (FR) to sit thereon facing in a forward direction (see Figure 2) so that the rider can steer and pedal the cycle (10) in the normal way. The rear seat (26, 32) serves to allow a rear rider (RR) to sit generally "back-to back" or "shoulders-to-back" with a front rider (FR) the rear rider so facing in a backward direction. The low rear seat combined with the backrest allow a rear rider (RR) to sit comfortably therein and advantageously to exert considerable force upon rear pedals (34) thereby allowing greater motive power to be generated. This is particularly important where the vehicle is being used to pull a trailer and/or to traverse rough terrain. The cycle has at least one pivotally mounted sidebar (70) that may be raised and lowered provided for the rear cyclist/rider to rest an arm upon or to hand-hold. Figure 3 shows how a pair of sidebars (70a, 70b) are pivotally connected (58) to the vertical tube (20a). These sidebars greatly reduce the likelihood of a rear rider falling off the rear seat (26) when riding the cycle/vehicle.

Figure 4a shows the front crankshaft (12e), crank-arms and pedals (24) and also the general arrangement of the front gear sprockets (36a, 36b), an outer (crossed) drive chain (38) and a conventional inner drive chain (40), rear gear sprockets (44, 46), rear crankshaft (42), one crank- arm and one rear pedal (34). The front crankshaft has a front outer gear sprocket wheel (36a) and a connected inner front gear sprocket wheel (36b) that mesh with the outer drive chain (38) and inner drive chain (40) respectively. The rear wheel axle (42) is rotationally mounted in apertures (22h) and is directly connected to a rear outer gear sprocket (44) that meshes with the outer drive chain (38). An inner rear gear sprocket (46) and a connected sleeve (48) are rotatably mounted on the rear wheel axle (42). The outer surface of the sleeve (48) has a (male) mesh or the like (50) configured to engage a corresponding (female) mesh (52) inside the hub (54) of the rear wheel. Optionally, there may be a conventional freewheel mechanism (not shown) between the inner rear gear sprocket (46) and the sleeve (48); in which event they will not be directly connected. Such a freewheel mechanism advantageously allows the riders to refrain from pedalling the vehicle; for example, when it is slowing down or at times when it is travelling downhill.

In use pedal power provided by a front rider (FR) is transmitted (see Figure 4a) via the front pedals (24) and crank members to the inner front sprocket wheel (36b) and through the inner drive chain (40) to the sleeve (48) and thence to the rear wheel hub (54) via the male-female mesh arrangement. Pedal power from a rear rider (RR) is first transmitted via the rear pedals (34) and crank members to the outer rear sprocket (44) through the outer drive chain (38) to the outer front sprocket wheel (36a) and thence to the connected inner front sprocket wheel (36b) and via the outer sprocket wheel (36a) to the rear wheel hub (as described above). Optionally, there may be a freewheel mechanism (not shown) between the front pedal crank and the front sprocket wheels (36a, 36b); thus allowing the front rider to refrain from pedalling whilst concentrating on steering, whilst still allowing the rear rider to provide pedal power to the vehicle.

It will be appreciated that owing to the back-to-back seating arrangement that the front pedals (24) will be pedalled in the opposite direction to the rear pedals (34). For this reason the outer drive chain (38) follows has a cross over (figure-eight) arrangement. This ensures that when the vehicle is being pedal powered by two riders that they do not oppose one-another; but rather that their power are combined and transferred to the rear wheel via the inner drive chain (40). A chain guide (64), mounted (see Figure 1 ) to one of the lower arm stays (22b), is provided proximal the crossover point of outer drive chain (38) to prevent wear by factional contact that would otherwise occur at this point.

The cycle described above is especially adapted to readily allow the rear wheel (16) to be detached and replaced by a trailer (100) that has two pairs of wheels connected by continuous tracks (see Figures 8a and 8b). The trailer (100) comprises a rectangular shaped load bearing surface (102) supported by a pair of generally rectangular shaped axle frames ( 104a, 104b) located underneath each side of the surface (102); inset somewhat from the side edge to allow space for continuous tracks (1 14 - see below). A front axle (106) and a rear axle (108) are supported by the axle frames (104a. 104b). Four wheels are rotationally mounted at the ends of the axles (106, 108). A first pair of wheels (1 10a, 1 10b) are located under one side edge of the load bearing surface and a second pair of wheels (112a, 112b) are located under the opposite side edge. These wheels (1 10, 112) are relatively wide and present a cylindrical outer surface that has protrusions spaced around thereof (not shown) so that optionally the pair of wheels on each side of the trailer each engage/grip a continuous and flexible track (114).

The front axle (106) has a drive sprocket wheel (1 16) fixed around the centre; provided to allow a drive chain (see latter) from the cycle (10). A pair of "V-shaped" brackets (1 18a, 1 18b) are each pivotally mounted (each side of sprocket 1 16) at a first end to the front axle (106); and the second ends of each bracket have angled open tubular portions ( 120) configured to accept an inverted "U-shaped" tubular member ( 122) that has a "T-shaped" handle (124) pivotally attached to the upper centre portion thereof. When the trailer ( 100) is being used alone these members (122, 124), and the handle in particular, are used to pull the trailer over the ground; the ends of the U-shaped member (122) being engaged within the four open angled tubular portions (120) of the "V-shaped" brackets. Optionally, a stay (126) is provided (see Figure 8a) to prevent movement of the "V- shaped" brackets (1 18) relative to the trolley chassis or load bearing surface (102). The stay (126) provides a rigid connection between the trolley chassis (104) or load bearing surface (102) and the "V-shaped" brackets (1 18) or the trolley handle (124). The stay (126) is preferably detachable and is only required when the trolley is being used without the cycle ( 10).

Figure 9 shows a perspective view of the trailer (100) attached to the cycle (10) and Figure 10 illustrates a partial perspective view of the front of the trailer (100) and the rear of the cycle (10) and shows the handle (124) with its pivotally connected "U-shaped" member (122) being pushed through the four open angled tubular portions (120) of the trailer that are aligned with open vertical tubular portions (22d, 22e) of the cycle; thereby connecting the cycle and the trailer. The handle portion (124) is preferably pivoted to a horizontal position before making this connection; this allows the free end of the handle (124) to be held under the cycle rear seat (26) by a clip or the like (not shown).

Prior to connecting the cycle (10) to the trailer (100) it is necessary to remove the rear wheel (16) of the cycle. Figure 3 illustrates this step. The rear pedals (34) and connected crank-arms are detached from the crankshaft (42) which is then unbolted from the wheel stays (22). This allows the wheel stays (22) to be pivoted apart (as shown) and the hub (54) of the rear wheel (16) to be detached from the sleeve (48). The wheel and hub are then replaced by a sprocket bush (56); illustrated in Figure 5. The sprocket bush comprises a sprocket (62) mounted on a bush (58) that has (an internal) female mesh (60) that engages a corresponding male mesh (50) on the surface of the outer sleeve (48 - that is connected to inner rear gear sprocket). A drive chain (128) is then fixed around the trailer axle drive sprocket (116) and around the bush sprocket (62); the wheel stays are pivoted to allow the axle (2) to be bolted (re-attached) thereto; and the crank-arms and pedals (34) are re-attached. Pedal power can now be transmitted from riders (FR, RR) via rear axle (42) of the cycle (as described above); bush sprocket (62); drive chain (128); trailer axle sprocket (116) and trailer axle (106) to the front pair of trailer wheels (1 10a, 1 12a). It will be noted that the configuration of the "V-shaped" brackets (118) and the inverted "U-shaped" member (122) allow the drive chain (128) unimpeded access as it moves to drive the trailer drive sprocket and connected axle (1 16, 106). Figure 1 1 shows a side view of the cycle (10) connected to the trailer (100). It will be noted that the pivotal attachment of the "V-shaped" shaped brackets (118a, 118b) allows the trailer (100) to pivot (about the front axle 106 of the trailer) relative to the cycle portion (8). This allows the vehicle to more easily traverse ramps, bumpy ground, etc.

Figures 12-16 diagrammatical ly illustrate a second embodiment of a transport system according to the present invention. Figure 12 shows a perspective view of a tandem tricycle, and Figure 13 shows a side elevation of the tricycle shown in Figure 12.

The cycle (200) has a front portion (202) comprising; frame (204) and a conventional front wheel (206) with a hub/bearing (208) and spokes (not shown); and a two rear wheels (210a, 210b) mounted on an axle (212). The front part of the frame (204) is approximately triangular in configuration and comprises a top tube (204a); a head tube (204b); a down tube (204c) and a seat tube (204d) with a crankcase (204e) at its lower extremity that houses a crankshaft connected to a pair crank-arms and front pedals (214). The head tube (204b) houses a conventional front fork member (204f) to which the front wheel hub/bearing (208) is fixed; the upper part of said fork (204f) is connected via a headset (204g) to conventional front handlebars (204h). A front seat (216) is connected to the seat tube (204d) as in a conventional bicycle.

The rear portion of the cycle (218) comprises a rear seat support assembly (220) and a pair of rear wheels (210a, 210b) attached to a rear axle (212); the rear axle being rotationally mounted on a pair of "V-shaped" bracket member (224a, 224b) each separately connected to one of a pair of wheel stays (222) by a "U-shaped" tube (226). The rear seat support assembly (220) has an inverted "T-shaped" portion comprising an upper vertical tube (220a) and a horizontal rear seat support tube (220b). The top end of the vertical tube (220a) is connected to the junction of the top tube (204a) and seat tube (204d). The lower end of the vertical tube (220a) is connected to the horizontal seat tube (220b). The seat support tube (220b) may be generally "D-shaped" (in plan view) in order to facilitate support of a rear seat (228). Two tubes (220c) extend vertically downward from beneath the horizontal seat tube (220b). The wheel stays (222) are attached to these tubes (220c). The combination of the vertical tube (220a), the seat support rube (220b) and the tubes (220c) provide a support assembly (220) that is generally of "wishbone" shape. The lower ends of the tubes (220c) are also connected to the crankcase (204e) by a further wishbone shaped member (230).

The rear seat (228) is located at a lower level than the front seat (216). This allows a rear seat backrest (230) to be located below the front seat (216) and to be supported by an inverted "U-shaped" tubular frame (232) connected to the "D-shaped" seat support tube (220b). Alternatively, the seat backrest (230) may be connected to and supported by the vertical tube (220a) portion of the support assembly (220).

The front seat (216) serves to allow a front rider (FR) to sit thereon facing in a forward direction so that the rider can steer and pedal the cycle (200) in the normal way. The rear seat (228) serves to allow a rear rider (RR) to sit generally "back-to back" or "shoulders- to-back" with a front rider (FR) the rear rider so facing in a backward direction. The low rear seat combined with the backrest allow a second rider (RR) to sit comfortably therein and advantageously to exert considerable force upon rear pedals (234) thereby allowing greater motive power to be generated. This is particularly important where the vehicle is being used to pull a trailer and/or to traverse rough terrain.

Each rear wheel stay (222) comprises an upper arm (222a) and a lower arm (222b) both connected at a first end to the tube (220c). The second end of the upper and lower arms each have an open vertical tubular portion (222d, 222e) used to connect the wheel stays (222) to the rear wheel axle and wheel assembly (210, 212, 236 - see below). Each rear wheel stay also has a strengthening cross stay (222f).

The rear axle of the cycle (212 - see Figure 12) has a drive sprocket wheel (236) fixed around the centre; provided to engage a drive chain (238 - see below). A pair of "V- shaped" brackets (224a, 224b) are rotationally mounted (each side of sprocket 236) at a first end to the rear axle (212); and the second ends of each bracket have angled open tubular portions (240) configured to accept an inverted "U-shaped" tubular member (226); the ends of the U-shaped member (226) being engaged within the four open angled tubular portions (240) of the "V-shaped" brackets (224).

A crankcase (242) is attached between mounting plates (244) located near the rear end of each rear wheel stay lower arm (222b); and this crankcase houses a crankshaft connected to a pair of crank-arms and rear pedals (234). The front pedal crankshaft and the rear pedal crankshaft each have a drive sprocket wheel; these being connected by a "figure eight" configured drive chain (246). A chain guide (248), mounted (see Figure 12) to one of the lower arm stays (222b), is provided proximal the crossover point of outer drive chain (246) to prevent wear by frictional contact that would otherwise occur at this point. The rear pedal crankshaft also has second sprocket wheel mechanically connected to the rear axle sprocket (236) by a further "figure eight" configured drive chain (238). It will be noted that the configuration of the "V-shaped" brackets (224) and the inverted "U- shaped" member (226) allow the drive chain (238) unimpeded access as it moves to drive the rear wheel drive sprocket (236) and connected axle (212).

The cycle described above is especially adapted to readily allow the attachment of a trailer (see Figures 14a and 14b). The trailer (300) comprises a rectangular shaped load bearing surface (302) supported by a pair of generally rectangular shaped axle frames (304a, 304b) located underneath each side of the surface (302); inset somewhat from the side edge to (optionally) allow space for continuous tracks (not shown). A rear axle (308) is supported by the axle frames (304a. 304b). Two wheels (310) are rotationally mounted at the ends this axle (308). These wheels (310) are relatively wide and present a cylindrical outer surface that has protrusions spaced around thereof so that (optionally) in use a pair of wheels on each side of the trailer (see below) each engage/grip a continuous track. At the front end of each axle frame is an axle clip (312a, 312b - shown schematically). When it is desired to attach the trailer (300) to the cycle (200) these clips (312) are placed over the cycle rear axle (212) of the cycle and locked into place. The clips (312) are configured so that the trailer (300) can pivot about the longitudinal axis of the rear axle (212). This allows the vehicle (200, 300) to more readily traverse inclines and bumpy ground. Pedal power can be transmitted from the front rider (FR) via front pedal axle, sprocket, and "figure-eight" chain (246) to the rear rider (RR) pedal axle (242) and thence via the second "figure-eight" chain (238) and rear axle sprocket (236) to the rear axle (212) and wheels (210).

Figure 15 shows a perspective view of the trailer (300) attached to the cycle (200). Figure 16 shows a corresponding side view. It will be noted that the pivotal attachment of the "V-shaped" brackets (224a, 224b) allow the trailer (300) to pivot (about the axle 212) relative to the cycle portion (200). This allows the vehicle to easily traverse ramps, bumpy ground, etc.

Optionally, the rear axle (212), drive sprocket (236), pair of wheels (210a, 210b) and V- shaped brackets (224a, 224b) may be replaced by a single wheel with a hub and drive sprocket (not shown); said hub being rotationally mounted between a further pair of V- shaped brackets (that is the same as brackets 224); these brackets again being connected to the rear portion (220) of the cycle frame (222) by the inverted "U-shaped" member (226). This advantageously allows the tricycle to be readily converted to a bicycle; thus making it more suitable for recreational use.

While the rear wheel of the bicycle (10) will normally be removed in order to provide a tricycle (200) or a bicycle-trailer hybrid (200, 300) the vehicle of the present invention may be easily converted to become a static pedal-powered "motor" to drive domestic/agricultural equipment. Thus, if the coupling (224) of the tricycle (200) is removed from the rear-end thereof and this rear-end is supported on static stilts; the sprocket bush (56) of the rear sprocket (46) may be connected by a drive chain (not shown) to the drive shaft (not shown) of such domestic/agricultural equipment. This offers considerable advantages in Third-World countries where short term power is needed; for example, to drive pumps and grinders etc. It also, advantageously, allows considerably more power to be generated than from an adapted conventional bicycle owing to the use or two persons to provide pedal power.