COMBINED BRAKE-OPERATING AND GEAR-OPERATING ASSEMBLY

Abstract: A combined handlebar-mounted assembly of a gear-operating lever (10) and brake-operating lever (12) permits bicycle gears to be changed to a lower ratio by pulling lever (10) away from lever (12) and to a higher ratio by pushing lever (10) into the channel-shaped back of lever (12). If lever (12) is pulled to apply the brake, the gear ratio is unchanged. One mechanism for achieving this uses brake-operating lever axis (32) to journal a gear-operating wire wind-up drum (33) carrying ratchet teeth (33C) controlled by escapement pawl (36). Gear-operating lever (10) is pivoted on support member (31), itself also pivoted at 32. Pulling lever (10) away from lever (12) first tilts lever (10) about its support member pivot axis and then causes a serrated end (27) of lever (10) to engage drum periphery (33A) whereafter the support member (31) and lever (10) pivot together about axis (32) to move the drum one wind-up unit, manually one tooth. Pushing lever (10) towards lever (12) causes it to abut at 31d and tilt the support (31) anticlockwise, so that projection (34) frees the escapement pawl (36) to allow the ratcheted drum (33) to revolve. Pulling lever (12) inwards pivots the whole internal assembly at 32; the lever (10) is still in essentially unchanged relative position to the drum serrations (33A) and abutment (31D) so that no gear change takes place.

Description: COMBINED BRAKE-OPERATING AND GEAR-OPERATING ASSEMBLY This invention relates to a combined assembly of a brake-operating lever and a gear-operating lever for a bicycle. i A conventional brake-operating lever for a bicycle is a smoothly externally contoured first-order lever attached to the handlebars (typically one to each side) so that the major arm of the lever can be moved towards the handlebars merely by extending the fingers of the rider and pulling the lever inwards. The minor arm then moves outwards, pulling a cable wire, which at its remote end tightens a brake on one or other wheel. A conventional gear-operating lever can be mounted on the handlebars or on the bicycle frame. It is, smaller than the brake lever and the mechanism -A^ atttaches to is so configured that the lever can be operated step-wise in either direction and then halted, to give to an attached cable a unit movement ^equivalent to a single gear-change at a gear change mechanism associated with the rear axle or with the drive' 1 sprockets. To brake, the essential grip on the handlebars is unchanged, but to effect a gear-change the cyclist must release his grip on the handlebars for each change. " Control of the bicycle is temporarily diminished, and fatigue to the user builds up over a period especially under race conditions. The present invention sets out to provide a combined assembly of a brake-generating lever and a gear-operating lever for a bicycle such that either lever can be operated by the cyclist without substantial alterations of hand position on the handlebars. In one aspect the invention consists in a combined assembly of a brake-operating lever and a gear-operating lever, for mounting on the handlebars of a bicycle, in which a gear-operating lever is located relative to a brake-operating lever so that parts at least of the two levers jointly define an open gap, the two levers being mounted for combined, generally non-relative, movement to effect a braking action only, when the brake operating lever is pulled, and for separate relative movement, to effect a gear-changing operation only, both when the gear-operating lever is pushed manually outwards to diminish the said gap and when the gear-operating lever is pulled manually inwards to separate from the brake-operating lever by increasing the said gap. Usually the gear-operating lever lies generally behind the gear-operating lever. Most typically the gear operating lever and the brake operating lever are each generally channel-shaped, and the gear operating lever, (a) at an inner region, lies behind and generally within the channel of the brake-operating lever, (b) over a central region lies behind and generally outside of the said channel whereby when the assembly is mounted on handlebars the gear-operating lever can be pressed manually into said channel to effect a gear-change operation, and (c) at an outer region diverges from the brake operating lever to define a gap whereby when the assembly is mounted on handle bars the gear-operating lever can be pulled manually away from said brake-operating lever to effect an opposite gear-change operation. It is usually envisaged that a wind-up and release drum to which the wire of a gear-operating cable is attached is journalled about the pivot axis of the brake-operating lever. Detailed embodiment for achieving this operation as defined in claims 5, 6 and 7. Advantageously, an arcuate gear-number indicator is attached for rotation with the drum so as to show which gear is currently engaged. In another aspect the invention consists in a bicycle having at least one such assembly as described above attached to the handlebars. By way of example the bicycle has two such assemblies one, for clamping the rear-wheel axle gear and applying the rear brake, connected to the right hand portion of the handlebars and the other, for changing the drive wheel gear and applying the front brake, connected to the left hand portion of the handlebars. As an additional feature the bicycle may include an automatic relative length compensator for the cables comprising a pivoted lever connected at one end to a cable wire and at the other end to the sheath of the other cable whereby wire extension to the axle gear change automatically adjusts the effective cable length to the drive gear change. It may also comprise a cable tension adjuster including a cam, rotary about an axis transverse to the cable, and through which a cable wire passes; a cam follower, of generally cylindrical shape and of the same diameter as the cable sheath, through which the wire also passes, the cam follower being imparted a movement longitudinal of the wire by cam rotation and being mounted to abut the sheath and alter its position relative to the wire as a tension adjuster. The invention will be further described with reference to the accompanying drawings, in which: Figure 1 is the a view of a bicycle equipped with a combined assembly, in accordance with a first embodiment of the invention, of a brake-operating lever and a gear-operating lever, at each side of the handlebars. Figure 2 is a side view of a slightly modified embodiment of one of said combined assemblies, partly in section and cutaway, and in simplified illustration, clamped to part of the handlebars. Figure 3 is a side view as in Fig 2 but with the brake lever removed, < Figure 3A shows from the front a cable pulley for the gear change cable. Figure 4 is a side view as in Fig. 3 but with further component parts removed; Figure 5 is a corresponding side view to Fig. 4, showing the removed parts; Figure 6 is an exploded view of a further embodiment of the internal mechanism of said combined assembly, Figure 7 is a side view, generally as in Fig. 3, of a yet further embodiment of the internal mechanism of the invention. Figure 8 shows in diagrammatic plan view a compensator arrangement for a gear cable, for use with any embodiment of the present invention. Figure 9 shows an exploded view of yet a further embodiment of the internal mechanism of the invention, having similarities to that of Fig. 6; and Figures 10a and 10b show a cable adjuster mechanism. A bicycle 1 has front wheel 2 and rear wheel 3. At the front wheel 2 there is a conventional brake mechanism with operating cable 4a extending to brake operating lever 13, on the left portion 5a of handlebar 5. Lever 13 is generally U-shaped in cross section. At the rear wheel 3 there is a further conventional brake mechanism 6 with operating cable 6a extending to brake operating lever 12, on the right handlebar portions 5b. Also at the rear wheel 3, at hub region 7, there is a conventional gear-change mechanism 8, connected by cable 8a (not shown in its entirety because extending behind the frame of the bicycle) which passes up within the handlebar tubing to extend eventually to gear operating lever 10 of generally similar contour to lever 12 but somewhat smaller, lying partly within but (in its neutral position) slightly spaced from the said lever 12 by distance F at the outer end. Finally, at the drive sprocket 9 there is an additional gear change mechanism 15 with cable 15a passing via compensator 16 to lever 11, which is in all respects similar to lever 10. Figs 2 to 5 can conveniently be considered together. They show in more detail the assembly of brake operating lever 12 and gear-operating lever 10 as shown in Fig. 1, slightly modified in the minor respect that brake cable 6a, in Fig. 2 to 5, also passes at least initially within the handlebar tubing rather than loop freely upward as shown in Fig. 1. The assembly comprises a main shell or case 17 fixed by fixing block 18 to the right portion 5b of handlebars 5 by means of bolt 19. The upper part of block 18 holds and restrains the cover of operating cables 6a and 8a so that the internal wires 6a' and 8a' can project for attachment to their respective operating systems. Thus, wire 6a' terminates in stopper 20 held in groove 21 of brake operating lever 12. Wire 8a' is wrapped round and connected to a pulley 33 as described in more detail below. Across the assembly lies main transverse shaft 32. The handle 12 pivots about this shaft 32 so that the - more the handle 12 is caused to approach handlebar portion 5b the more the wire 6a' is pulled and the more brake assembly 6 is applied. Pulley 33 is loosely journalled within case 17 about shaft 32. As shown in Fig. 3a it comprises a first zone of fine serrations at 33A, a second zone as a wire wind-up drum 33B and a third zone with ratchet teeth 33C. Wire 8a 1 surrounds the drum 33b to terminate in conventional anchor cavity 33d (Fig.3). Also pivotable about shaft 32 is a pair of shaped end or support plates 31. Each projects slightly ahead of case 17, at 31a. The plates are joined by a cross-piece 31b. Between the two plates 31 is fixed a forward shaft 30, (not engaging case 17) acting as a pivot shaft for gear-operating lever 10, and a rearward shaft 34 the function of which will be described in more detail below. Gear-operating lever 10 has an upper rearward face with serrations 37 matching the ' serrations 33a. Separately from plate 31, and spaced below a rearward portion thereof, a further shaft 35 extends within case 17, forwardly of shaft 34 in plates 31. As best shown in Fig. 4, where plate 31 is removed, a pawl plate 36 is mounted about shaft 35 and possesses, a primary detent 36a, a secondary detent 36b and a rearward operating arm 36c biassed upwards at spring 37 against shaft 34. In addition to the normal tensions on the wires 6a' and 8a', spring 39 about shaft 32 assists in holding ratchet teeth 33C against the detents. Similarly, spring 38 assists gravity in holding gear-operating ^ lever 10 in its shown position between stop 31b and serrations 33A. The device operates as follows:- (a) to change to a lower gear Gear-operating lever 10 is pulled back, away from the brake-operating lever 12, by inserting the fingers into the gap F and pulling back. Initially, it rotates about axis 30. Very soon, however, it can no longer rotate because it hits and engages serrated zone 33A of drum 33 with its own serrated face 37. Surfaces 33a and 37 are now locked together. Further finger pressure now causes drum 33 to turn about shaft 32. This continues until the ratchet teeth 33C have clicked once, the available extent of arm 10 movement being such as to ensure that one and only one ratchet tooth 33C is passed, so that a unique gear setting is achieved. If desired more than one tooth could be traversed in movement of the pawl. Once pressure is relieved on handle 10 the serrations 33A and 37 no longer bind together. A spring bias at 39 on the handle will swing plate 31 back until the original appearance re-appears; drum 33 will of course still be in the described position since main detent 36 is holding it against rotation and thus holding the bicycle in a desired gear. (b) to change to a higher gear ratio Gear-operating lever 10 is pushed forward, by the outside of the cylists' hand, so as to close up gap F. It soon reaches transverse stop 31b, and plate 31 starts to rotate anticlockwise. Thus transverse shaft 34 bears down on rearward protrusion 36c of detent plate, 36, thereby releasing primary pawl 36a from its tooth. The drum rotates back, due to the tension within wire 8a', but is caught in the secondary pawl 36b. Further operating pressure at 34 cannot however dislodge this secondary pawl 36b. This can only be done on release, when spring 37 pushes primary pawl 36a back into engagement with the desired tooth, one click further on. The effect is rather like a clock 'escapement' mechanism. From the above passages (a) and (b) it will be apparent that only one gear movement per full operation can be achieved, whether forward or backward operation. (c) to operate the brake Brake-operating lever 12 is pulled inward toward handlebar position 5b. Very soon it contacts plate 31, at 3ID. On further pressure it causes plate 31 and also the lever 10 to rotate about shaft 32. Since however, the serrated edges 33A and 37 do not come into contact, drum 33 is unmoved at whatever location pawl 36a requires. In other words, brake operation does not affect the gear changes in any way. Figure 6 shows a different type of 'click' or ratchet movement operable by the same type of serrated gear-operating lever 10. Only that portion corresponding to drum 33 and its pawls 36a, 36b is shown. A shaft 49, keyed at 48 to be non-rotary in the case 17, supports wind-up drum 45, serrated at 45a, for wire 8a". Drum 45 is fast with inner annulus 44 having peripheral castellations 46 with angled faces. This annulus 44 lies within surround 42 internally castellated at 43 and is outwardly biassed (47) in relation to the surround. Portion 41 of support plate 40 (compare end plate 31 in Figs 2-4) has three inclined stepped ramps or faces 41a which cooperate with like structure 42a at the rearward side of surround 42. To operate the gear change when the lever 10 is moved clockwise the lever engages serrations 45a and causes the gear cable pulley 45 and the annulus 44 to rotate. Castellations 43 then slide diagonally through the diagonal gaps between the castellations 46 causing keyed surround 42 to slide along the shaft without rotation. This causes the biassing axial compression spring (not shown) to be compressed until the castellations 43 have reached the top of their diagonal slide. They then spring sideways under the action of the axial spring causing their flat faces to engage with the flat faces on the castellations 46, and thus bring about one gear-changing wind-up step. When the lever 10 is moved anti-clockwise, the sloping ramps 41a on the face of the ring 41 slide up the corresponding ramps 42a on the back face of the surround 42. This pushes the surround 42 away from the ring 41 and compresses the internal axial spring at 47. The castellations 43 then disengage from the castellations 46 i.e. the corresponding flat faces slide past each other. The annulus 44 and pulley 45 are then free to rotate by one gear change distance, during w^iich the castellations 43 re-trace the path they took when the lever was moved in a clockwise direction. Figure 7 shows an embodiment similar to tha " t of Fig.3 but with a different operating arrangement for drum 33. In Fig. 7, drum 33 and its component parts 33B and 33C; and pawl 36 with its parts 36A, 36B and 36C, and biassing spring 37 are all as in Fig.3. A cam 50 pivots about shaft 32 and is fixed relative to the brake-operating lever. Pawl 51 is biassed at 51a to engage teeth 33C unless the position of cam " B ' O prevents such engagement. To change gear in one direction, handle 10 is pulled; pawl 51 slides off the end of cam 50, engages a tooth, and pushes the drum one 'click' past pawl 36a. To change gear in the other direction, the handle 10 is pushed and shaft 34, attached in this case to extension 10a of lever 10, presses the pawl 36 down at 36a for the necessary escapement action in Fig.3. To brake, handle 12 is pulled. Cam 50 travels with this handle, and handle 10 also moves. However, pawl 51 cannot reach teeth 33C because of the moved cam, so the gear is unchanged. Figure 8 shows a compensator arrangement. Gear cable wire 15a' is interconnected by bar 53 pivoted at 53a and springbiassed at 53b between barrel 52, attached to wire 15a* and sheath 8a. Whenever the wire 8a' is moved, the outer sheath 15a is automatically moved by the bar 53 in a compensating manner to alter the effective length of the cable 15a. In practice this means that the fine adjus sment required to a chain guide selector of the gear changer 15 to prevent it scrubbing the chain is automatically carried out during gear changes at the wheel by operation of the lever 10 and the action of the compensator arrangement 16. Figure 9 shows a embodiment of wind-up drum and shaf generally equivalent to that of Figure 6. Cover parts 91, 92 fit by recesses 91a, 92a, to lugs 93 around the periphery of a winding drum 94. These cover parts carry out one end a protruding part circular gear-number indicator 95. Biassing spring 96 biasses in sequence, a face-tooth wheel 97, on a square shaft meshing for one-click movement with a complementary counterpart not shown, on the rear face of the drum; the drum; and a driving f ce-tooth wheel 98 but mounted for relative rotation and meshing for one-click movement at face gear 99 of the drum. On the wheel 98, at the face outward from the drum is a release wheel arrangement 10D, with inclined ramps to mesh or disengage into the facing side of wheel 101. To change to a lower gear, drum 94 is rotated by lever 10, as in Figs 2, 3 or 4. Its hidden face teeth push on the face teeth of wheel 97 so that this (non-rotation) wheel presses back on and slides towards the spring 96 until it clicks to effect and notify one gear change. To change to a higher gear, lever 10 is pushed forward. This turns wheel 101, mounted as part of a support or subframe (compare 31 in Figs 2 - 5). The ramps on this wheel 101 slide along ramps 100 on wheel 98, and so push wheel 98, bush 98a and ratchet disc along the shaft against biassing spring 96. However, the wheel 100 is meshed by face teeth with drum 94. This when the lever 10 is released, wheels 97, bush 98a and wheel 98 are all pressed back and the drum becomes located in the next ratchet space. Slots 102 in end or case pieces 104 (compare 17) define a maximum extent of drum rotary travel and permit gear selection indicator 95 to protrude for inspection. Figures 10a and 10b show a simple form of cable adjuster. Attached to bicycle frame 110, by an axial bolt 112 with outer knurled disc 112a rotational thereon, is a cylindrical housing 114 with generally tangential tubular extension 116. Around the bolt is fixed a cam 118, formed in two parallel plates 118a, 118b. A cable 120 passes into the tubular extension 116. Its wire 120a passes between the cam walls. A shaped cam follower 122 is interposed, around wire 120a, between the cam 118 and cable sheath 120b. Thus, rotational adjustment of the disc 112a can turn the bolt, thus turn the cam, move the follower, and adjust the cable relative to the sheath and hence the wire tension.

Claims: CLAIMS : 1. A combined assembly of a brake-operating lever and a gear-operating lever, for mounting on the handlebars of a bicycle, in which a gear-operating lever is located relative to a brake-operating lever so that parts at least of the two levers jointly define an open gap, the two levers being mounted for combined, generally non-relative, movement to effect a braking action only, when the brake operating lever is pulled, and for separate relative movement, to effect a gear-changing operation only, both when the gear-operating lever is pushed manually outwards to diminish the said jgap and when the gear-operating lever is pulled manually inwards to separate from the brake-operating lever by increasing the said gap. 2. A combined assembly as claimed in claim 1 in which the gear-operating lever lies generally behind the brake-operating lever. 3. A combined assembly as claimed in claim 1 in which the gear operating lever and the brake operating lever are each generally channel-shaped, and the gear operating lever, (a) at an inner region, lies behind and generally within the channel of the brake-operating lever, (b) over a central region lies behind and generally outside of the said channel whereby when the assembly is mounted on handlebars the gear-operating lever can be pressed manually into said channel to effect a gear-change operation, and (c) at an outer region diverges from the brake operating lever to define a gap whereby when the assembly is mounted on handle bars the gear-operating lever can be pulled manually away from said brake-operating lever to effect an opposite gear-change operation. 4. A combined assembly as claimed in claim 1, 2 or 3 in which a wind-up and release drum to which the wire of a gear-operating cable is attached is journalled about the pivot axis of the brake-operating lever. 5. A combined assembly as claimed in claim 4, in which: the brake-operating lever comprises a major arm for the said manual operation, a pivot axis, and a minor arm to which the wire of a brake operating cable is attached; the wind-up and release drum to which the wire of the gear-operating cable is attached is ratcheted about the said pivot axis of the brake-operating lever; a support for the pivot of the gear-operating lever is additionally pivoted about said pivot axis of the brake-operating lever; and the gear-operating lever is biassed or mounted to lie in a neutral position clear of the said drum; whereby (i) pulling the gear-operating lever engages the drum and then rotates the drum and support for one ratchetted unit corresponding to a gear change, (ii) pushing the gear-operating lever forwards engages and tilts the support and causes it to disengage a ratchet pawl to release one ratchetted unit, corresponding to a gear change in the opposite direction, (iii) pulling the brake-operating lever reaϊwards engages and tilts the support without altering the relative location of the drum and gear-engaging lever, so as to leave the gears unchanged. 6. A combined assembly as claimed in claim 4 in which: the brake-operating lever comprises a major arm for the said manual operation, a pivot axis and a minor arm to which the wire of a brake-operating cable is attached; the wind-up and release drum to which the wire of the gear-operating cable is attached is ratcheted about the said pivot axis; the gear operating lever is pivoted about the said pivot axis and carries a driving pawl to engage a toothed surface of said drum and a release projection to release said ratchet, and a cam is journalled about said axis to move with said brake-operating lever, the cam presenting a face which deflects said drive pawl from said drum; whereby (i) pulling the gear operating lever rearwards causes the pawl to slide past the cam surface, to engage the drum, and then to rotate the drum for one ratchetted unit of movement corresponding to a gear change; (ii) pushing the gear-operating lever forwards causes the said release projection thereon to disengage and release a ratchet pawl; and (iii) pulling the brake-operating lever rearwards progressively moves the cam around to prevent the drive pawl of the entrained gear-operating lever from engaging the drum, so as to leave the gears unchanged. 7. A combined assembly as claimed in claim 4 in which: the brake operating lever comprises a major arm for the said manual operation, a pivot axis and a minor arm to which the wire of a brake-operating cable is attached; ■ the wind-up and release drum to which the wire of the gear-operating cable is attached is ratchetted about the said prior axis, the ratchetted drum comprising an externally toothed internal rotary member, and an external surround member non-rotary but capable of relative axial displacement and with internally projecting ratchet teeth and a non-return ramp structure at one end face; a support for the pivot of the.gear-operating lever is additionally pivoted about said pivot axis of the brake-operating lever and comprises a complementary ramp structure to the drum surround end face ramp structure; and the gear-operating lever is biassed or mounted to - lie in a neutral position clear of the said drum; whereby (i) pulling the gear-operating lever rearwards rotates the ratchetted drum and causes the internal rotary member to move one ratchetted unit within the external surround; (ii) pushing the gear-operating lever forwards engages and tilts the support and causes the ramp structures to interengage and move the external surround axially to disengage the internal rotary member by one ratchetted unit, and (iii) pulling the brake-operating lever rearwards engages and tilts the support without altering the relative location of the ramp structures or of the drum and gear-engaging lever so as to leave the gears unchanged. 8. A combined assembly as claimed in any of preceding claims 3 to 7 in which an arcuate gear-number indicator is attached for rotation with the drum so as to show which gear is currently engaged. 9. A bicycle having attached to the handlebars at least one assembly as claimed in any one preceding claim. 10. A bicycle as claimed in claim 9 which has two such assemblies one, for clamping the rear-wheel axle gear and applying the rear brake, connected to the right hand portion of the handlebars and the other, for changing the drive wheel gear and applying the front brake, connected to the lef hand portion of the handlebars. 11. A bicycle as claimed in claim 10 further including an automatic relative length compensator for the cables comprising a pivoted lever connected at one end to a cable wire and at the other end to the sheath of the other cable whereby wire extension to the axle gear change automatically adjusts the effective cable length to the drive gear change. 12. A bicycle as claimed in any one of claims 9, 10 or 11 comprising a cable tension adjuster including a cam, rotary about an axis transverse to the cable, and through which a cable wire passes; a cam follower, of generally cylindrical shape and of the same diameter as the cable sheath, through which the wire also passes, the cam follower being imparted a movement longitudinal of the wire by cam rotation and being mounted to abut the sheath and alter its position relative to the wire as a tension adjuster.

Inventors: COLLINS NICHOLAS JOHN, COLLINS, NICHOLAS, JOHN
Applicants: COLLINS NICHOLAS JOHN, COLLINS, NICHOLAS, JOHN
Application year: 1990
Main classification: B62L3
IPC codes: B62L3, B62M25