GB2618873A

GB2618873A - Bicycles

Info

Publication number: GB2618873A
Application number: GB2218723.1A
Authority: GB
Inventors: Hill Maurice
Original assignee: Development Ind Ltd
Current assignee: Development Ind Ltd
Priority date: 2022-05-18
Filing date: 2022-12-13
Publication date: 2023-11-22
Also published as: GB202218723D0; GB202207297D0

Abstract

A bicycle comprises a frame including a head tube, front and rear wheels, a fork rotatable within the head tube for steering, and a handlebar stem 18 including handlebars. The handlebar stem set is interlockable with the fork by means of a clutch 32, 36 in a first configuration for normal steering, and in a second configuration for storage. In the second configuration, the handlebar stem 18 is rotated about the axis of the fork from its position in the first configuration, preferably by 90°. The clutch allows movement from the first configuration to the second configuration and vice-versa without the need for tools and ensures correct alignment between the front wheel and the handlebars is maintained. Locking of the clutch may be by means of a handwheel 39.

Description

BICYCLES

This disclosure relates to bicycles. More particularly, it is concerned with how the width of a bicycle may be reduced to facilitate storage.

To reduce the space occupied by fixed frame bicycles including bicycles with the conventional diamond shaped frame, a variety of foldable bicycles have been proposed. However, with fixed frame bicycles, it is the width of the bicycle, primarily determined by the handlebars, that determines the space required for storage, for example on a rack mounted on the rear of a motor vehicle or on the garage wall of a garage primarily for housing a motor vehicle A conventional bicycle will have a front set in which a handlebar head set is coupled to a stem rotatable within a head tube forming part of the frame, the stem being coupled to a front fork for mounting a front wheel. Steering is by using the handlebars to rotate the stem and front fork about the axis of the head tube. Provision is made only for minor adjustment of the handlebar head set relative to the stem or of the handlebar headset and the stem relative to the front fork for proper wheel alignment. Any greater rotation of the handlebar headset relative to the stem or front fork requites tools. Moreover it is hard to reverse the rotation and leave the handlebar headset in condition for riding without a lot of adjustment.

According to one aspect of the present disclosure, there is provided a bicycle having a frame, the frame including a head tube, front and rear wheels; a stem rotatable within the head tube for steering; and a handlebar head set including handlebars, the handlebar head set being interlockable with the stem in two alternative configurations, namely. a first configuration for normal steering, and a second configuration for storage in which the handlebar head set is rotated about the axis of the stem from its position in the first configuration, preferably by 900; the handlebar head set being movable from the first configuration to the second and vice-versa without need for tools and without need for adjustment in alignment between the front wheel and the handlebars when moved to said first configuration.

Preferred embodiments have one or more of the following features: The handlebar head set includes a tubular member through which a distal end of the stem is received, a lower end face of the tubular member forming a first clutch member, and the outer surface of the stem including a flange with a second clutch member complementary to the first and for engagement therewith when the handlebar head set is in either of its first and second configurations. The clutch members have a castellated form with alternate projections and lands on the lower end face of the said tubular member of the handlebar head set engageable with corresponding alternate lands and projections on the flange. The sides of the said projections and lands are tapered to avoid jamming. The stem comprises a conventional stem to which an auxiliary stem piece has been fastened by three countersunk bolts located at equiangular positions about the circumference of the stem, the stem piece including said flange. The distal end of the stem is threaded to receive a hand-tightenable nut adapted to maintain the first and second clutch members in engagement when tightened. Alternatively, in embodiments incorporating the aforesaid stem piece, the distal end of the stem piece is threaded to receive a hand-tightenable nut adapted to maintain the first and second clutch members in engagement when tightened. A selectably lockable mechanism is provided to lock the handlebar head set to the stem in said second configuration to prevent the handlebar head set being moved from said second configuration to said first configuration while locked, thereby preventing the bicycle from being ridden until the selectably lockable mechanism is unlocked to allow the handlebar head set to be moved to the first configuration. The selectably lockable mechanism comprises a locking bolt mounted on the first clutch member, and a cooperating aperture in the second clutch member into which an end of the bolt is received when the selectably lockable mechanism is locked. The locking bolt is spring loaded and key operated, so that the mechanism may be locked simply by manually pushing the locking bolt inwardly against the bias of a spring into the aperture in the second clutch member, and unlocked by the key, whereupon the spring bias operates to push the locking bolt outwardly to release it from the aperture in the second clutch member. Alternatively, the selectably lockable mechanism comprises a padlock, and respective apertured lugs extending outwardly from each of the clutch members, the apertures being aligned when the handlebar head set is in the second configuration. The shackle of the padlock is passed through both apertures and locked.

In an alternative embodiment, the handlebar head set may include a tubular member through which a distal end of the stem is receivable, a lower end face of the tubular member being provided with a plurality of spaced notches, and the outer 5 surface of the stem being provided with a corresponding plurality of projections to the first and for engagement with the notches when the handlebar head set is in either of its first and second configurations. The stem may comprise a conventional stem to which an auxiliary stem piece is fastened, the auxiliary stem piece including the said plurality of projections. The distal end of the stem may be threaded to receive a hand-10 tightenable nut adapted to maintain the projections in engagement with the notches when tightened.

In a second and alternative aspect of this disclosure, the front set of a bicycle is converted from one of a first configuration for normal riding and steering and a second configuration adapted for storage of the bicycle to the other, by a method without need for tools and without the need for realignment of the front wheel and handlebars after movement to said first configuration, the method comprising the steps of: disengaging a first clutch member formed on a lower end face of a tubular member of a handlebar head set from a second clutch member formed on a flange 20 formed on the outer surface of a stem received in the tubular member, the stem being rotatable within a head tube of a frame of the bicycle for steering; rotating said tubular member about the axis of the stem by the angle, preferably 900, between the first and second configurations; and re-engaging said first clutch member with said second clutch member.

Preferably, the first and second clutch members are maintained in engagement with each other in said first and second configurations by a hand-tightenable nut threadedly engaged with the distal end of the stem; the method of conversion including a preliminary step of loosening or removing the hand-tightenable nut sufficiently to allow lifting of said tubular member in the axial direction of the stem sufficiently to disengage the first clutch member from the second clutch member, and wherein said re-engagement step comprises lowering said tubular member relative to the stem in the axial direction thereof to re-engage the first and second clutch members, and replacing or tightening the hand-tightenable nut to maintain re-engagement.

In a third alternative aspect of this disclosure, we provide a method of converting the front set of a bicycle from one of a first configuration for normal riding and steering and a second configuration adapted for storage of the bicycle to the other, without need for tools and without the need for realignment of the front wheel and handlebars after movement to said first configuration, the method comprising the steps of: disengaging a plurality of notches formed on a lower end face of a tubular member of a handlebar head set from a corresponding plurality of projections formed on the outer surface of a stem or on the outer surface of an auxiliary stem piece attached to a stem received in the tubular member, the stem being rotatable within a head tube of a frame of the bicycle for steering, rotating said tubular member about the axis of the stem by the angle, preferably 900, between the first and second configurations; and re-engaging the plurality of notches with the plurality of projections Preferably, the plurality of notches and the plurality of projections are maintained in engagement with each other in said first and second configurations by a hand-tightenable nut threadedly engaged with the distal end of the stem, the method further comprising a preliminary step of loosening or removing the hand-tightenable nut sufficiently to allow lifting of said tubular member in the axial direction of the stem sufficiently to disengage the notches from the projections, and a re-engagement step of lowering said tubular member relative to the stem in the axial direction thereof to re-engage the plurality of notches with the plurality of projections, and replacing or tightening the hand-tightenable nut to maintain re-engagement.

Reference may now be made to the accompanying drawings and the description below of preferred embodiments, in which:

S

Fig.1 shows a side view of a bicycle with a conventional diamond shaped fixed frame, the bicycle being shown in its first configuration suitable for normal riding and steering; Figs. 2a, 2b and 2c show respective side, front elevational and plan view of a 5 bicycle in its first configuration, the bicycle having a modified, but still conventional, fixed frame, more appropriate for female riders wearing a skirt; Figs. 3a, 3b and 3c showing similar views of the bicycle of Figs. 2a, 2b and 2c in its second configuration suitable for storage; Fig. 4 shows an enlarged perspective view of the front set of the bicycle of 10 Figs. 2a to 3c in its first configuration, with parts omitted for clarity; Fig. 5 shows a similar view to Fig. 4 with a hand-tightenable nut released and clutch members disengaged; Fig. 6 is a view similar to Fig. 5 after rotation of the handlebar headset through 900; Fig. 7 is a view similar to Fig. 6 showing the handlebar head set in its second configuration after re-engagement of the clutch members and tightening of the handtightenable nut; Fig. 8 is a perspective view of a stem forming part of the front set of Figs. 4 to 7; Fig. 9 is a perspective view of a stern piece adapted for use with an existing stem and a replacement handlebar head set to form a bicycle front set in accordance with the teachings of the present disclosure; Fig.10 shows a conventional existing stem modified for use with the stem piece of Fig. 9; Fig. 11 shows a scrap perspective view of a tubular member in engagement with a stern or an auxiliary stem piece, with parts omitted for clarity; Fig. 12 shows the tubular member and stem or auxiliary stem piece of Fig. 11 disengaged; Fig. 13 shows an exploded perspective view of an alternative embodiment, 30 with parts omitted for clarity; Fig. 14 is a perspective view of one embodiment of a selectably lockable mechanism showing the first and second clutch members disengaged, with parts omitted for clarity; Fig. 15 is a view similar to Fig. 14 showing the first and second clutch members engaged in the second configuration, and a locking mechanism in the locked condition; Fig. 16 is a view similar to Fig, 15 after rotation of the handlebar head set 5 through 900 to the first configuration, with the locking mechanism in its unlocked state; Fig. 17 shows an alternative arrangement for locking the handlebar head set, the head set being shown in this view in its first configuration; and Fig. 18 is a view similar to Fig. 17 showing the handlebar head set in its second 10 configuration ready to be locked by use of a padlock.

A bicycle 1 has a traditional diamond shaped frame 2 comprising a top tube 3, a head tube 4, a down tube 5, a seat tube 6, a pair of seat stays 7 on either side of a rear wheel 8 and a pair of chain stays 9 also on either side of the rear wheel 8. A rear cogset 10 is mounted on the axle of the rear wheel 8, and a chain 11 passes around the rear cogset 10 and one or more chain rings 12. The gear ratio is adjustable by respective rear 13 and front 14 derailleurs. The chain rings 12 are pedal driven by respective pedals 15 on the ends of respective crank arms 16 on either side of the bicycle, and drive is communicated to the rear wheel 8 via the chain 11, all in conventional fashion.

The bicycle has a front set comprising a handlebar 17 forming part of a handlebar head set 18 coupled to a stem 19 which is rotatably received in the head tube 4 and coupled to a front fork 20 typically via a conventional wedge and bolt system. The front fork 20 may incorporate shock absorbers 21 and front wheel 22 is supported via its hub 23 at the distal ends of the front fork 20.

A saddle 24 is supported on a seat post 25 received in the seat tube 6. Front 26 and rear 27 brakes are usually cable operated from levers 28 mounted on the 30 handlebar 17.

The bicycle I illustrated in Figs. 2a to 3c is essentially the same as that of Fig. 1 except for the frame 2 which has a lowered top tube 3 making it easier to mount for females wearing a skirt. As can be seen from Figs. 2b and 2c, the width of the bicycle is at its greatest at the handlebar 17, and, absent the teachings of the present disclosure, determines the space necessary to store the bicycle, for example on a storage rack on the rear of a motor vehicle or on the internal wall of a garage.

Figs. 3a, 3b and 3c show how much space may be saved when the handlebar head set is rotated from its first configuration for normal riding and steering shown in Figs. 2a, 2b and 2c by 90° to a second configuration.

Turning now to Figs. 4 to 7, which show successive stages in the conversion without using any tools of a bicycle from its first configuration shown in Figs. 2a, 2b and 2c to its second configuration shown in Figs. 3a, 3b and 3c, the embodiment of bicycle front set illustrated comprises a steering stem 19 which would be rotatably receivable in the head tube and coupled to the front fork typically via a conventional wedge and bolt system. The stem 19 is interlockable with handlebar head set 18 including a handlebar proper 17, illustrated only schematically.

The handlebar head set includes a tubular member 29 through which a distal end 30 of the stem 19 is received. Lower end face 31 of the tubular member 29 forms a first clutch member 32. As best shown in Fig. 8, the distal end of stem 19 is threaded at 33. The stem has an intermediate flange 34 formed on its outer surface 35. The flange 34 forms a second clutch member 36, the configuration of which is complementary to that of the first clutch member 32 and intended for engagement therewith. As will be apparent from the drawings, in this embodiment the clutch members comprise alternate projections 37 and lands 38. The sides of the projections 37 are preferably slightly tapered, more preferably at an angle of 1 in 6. This taper seeks to prevent the engaged first and second clutch members 32, 36 from jamming, for example through thermal expansion. For the same reason, a slight gap of the order of 0.25mm is preferably left between the end of a projection 37 of one clutch member and the bottom of a land 38 on the other when the first and second clutch members are fully engaged.

As shown in Fig. 4, a hand-tightenable nut 39, preferably with an intermediate spring washer is threadedly fastened to the screw thread formed on the distal end of the stem 19 and maintains the first and second clutch members 32, 36 in engagement.

Nut 39 is provided with a profile 40 for gripping by hand to tighten or loosen it. It will be appreciated that the members 32, 36 form a true clutch in the sense that rotational drive is transmitted from one to the other to steer the front wheel 22 from the handlebar 17.

In order to convert the illustrated front set from the first configuration of Fig. 4 to the second configuration, the nut 39 must first be loosened or removed Preferably, the nut 39 only needs to be loosened sufficiently for the tubular member 29 of the handlebar head set 18 to be raisable just enough for the first and second clutch members 32, 35 to be disengaged from each other, as shown in Fig 5 The handlebar head set 18 with its tubular member 29 can then readily be rotated by the angle defined between the first and the second configurations to the position shown in Fig. 6. This angle is preferably 900. However, this precise angle is not necessary. Indeed, depending on the number of projections and lands, and their need to interengage, a 90° angle may not be possible.

Tightening the nut 39 will then engage the first and second clutch members 32, 36 in the second configuration of the handlebar head set 18 relative to the stem 20 19, as shown in Fig. 7.

A stem 19 as illustrated in Fig. 8 will suitably be employed when manufacturing an embodiment of bicycle from scratch that is intended for ready conversion from the first configuration for normal riding and steering to a second configuration for storage. However, in the alternative, an existing bicycle can also be transformed into one that is readily convertible from the first to the second configuration and vice-versa in accordance with the teachings of this Application. A stem piece 41 as shown in Fig. 9 with a flange 34 providing the second clutch member 36 is required together with a modified handlebar head set 18 with tubular member 29 providing the first clutch member 32. Stem piece 41 will need to be fastened to the exiting stem 19, as shown in Fig.10. Stem piece 41 is hollow and provided with three countersunk openings 42 at equiangular positions about its circumference for receiving countersunk bolts. The stem 19 must be drilled and tapped at similar positions 43 to receive the respective countersunk bolts after passing through respective openings 42.

Because the first configuration is predetermined in all of the arrangements 5 described herein, when the front set is converted back to the first configuration no adjustment or realignment between the handlebars and the front wheel is required. The handlebar headset is automatically returned to the correct configuration for riding and steering. Accordingly, the movement from one configuration to the other and vice-versa can be readily accomplished by one person without tools or fuss and 10 without any adjustment or re-alignment.

While the arrangement of alternate projections and lands for respective clutch members works well, it will readily be appreciated that other forms of clutch, and, indeed, other arrangements are possible. All that is necessary is that the handlebar headset is interlockable with the stem in two configurations, one of which corresponds to the normal configuration for riding and steering, and the other of which can be reached simply by rotating the handlebar head set relative to the stem by hand by a predetermined angle, preferably, but not necessarily 900, to a second configuration for storage of the bicycle.

For example, referring to Figs. 11 and 12, tubular member 29 may have a plurality of notches 44, while the stem 19 (alternatively an auxiliary stem piece 41) is provided with a corresponding plurality of projections 45 that interengage as shown in Fig. 11. The distal end of the stem or auxiliary stem piece is threaded to receive a hand-tightenable nut 39, which serves the same purpose as in the previously described embodiment.

Fig. 13 shows an alternative way of providing an existing stem with a second clutch member 36 for engagement with a first clutch member 32 provided on lower end face 31 of a tubular member 29. In this arrangement, the second clutch member 32 is carried by an auxiliary stem piece 41 formed in two parts 41a and 41b which clamp about a conventional stem 19.

Figs. 14-16 show one embodiment of a selectably lockable mechanism for preventing the handlebar head set 18 from being moved from the second configuration for storage to the first configuration for normal riding, reducing the likelihood that the stored bicycle will be stolen. A locking bolt 46 is mounted on the first clutch member 32, and the second clutch member 36 has a cooperating aperture 47 into which the locking bolt 46 can be received to lock the mechanism. The locking bolt 46 is spring loaded and key operated. When the first clutch member 32 and the second clutch member 36 are engaged in the second configuration, the locking bolt 46 aligns with the aperture 47, and may be pushed inwardly to engage the locking mechanism, as shown in Fig. 15. A key (not shown) is used to unlock the locking mechanism, whereupon the spring bias operates to push the locking bolt 46 outwardly from the aperture 47, thereby releasing the aperture 47 in the second clutch member 36 from the locking bolt 46. The clutch mechanism may then be disengaged and rotated through 90° in this case and re-engaged to the first configuration as shown in Fig. 16 in which it will be noted that the spring loaded locking bolt 46 is shown in its outermost disengaged condition.

Figs. 17 and 18 show an alternative arrangement for locking the handlebar head set in the second configuration, preventing the handlebar head set from being moved to the first configuration, allowing the bicycle to be ridden. In this embodiment, the first clutch member 32 is provided with an apertured lug 48, and the second clutch member 36 is provided with a corresponding apertured lug 49, both lugs extending outwardly from their respective clutch member. When the handlebar head set 18 is in the second configuration, as shown in Fig. 18, apertured lugs 48 and 49 are aligned, and a padlock (not shown) may be used to lock the mechanism by passing the shackle of the padlock through the aligned apertured lugs 48 and 49, and securing the padlock to itself The padlock may subsequently be unlocked by key, allowing the handlebar head set 18 from the second configuration to the first to allow the bicycle to be ridden. Skilled persons will readily appreciate that a combination padlock could be used in place of a key operated padlock.

Claims

Claims 1 A bicycle having a frame, the frame including a head tube; front and rear wheels; a stem rotatable within the head tube for steering; and a handlebar head set including handlebars, the handlebar head set being interlockable with the stem in two 5 alternative configurations, namely: a first configuration for normal steering, and a second configuration for storage in which the handlebar head set is rotated about the axis of the stem from its position in the first configuration, preferably by 900; the handlebar head set being movable from the first configuration to the second and vice-versa without need for tools and without need for adjustment in alignment between 10 the front wheel and the handlebars when moved to said first configuration 2. A bicycle according to Claim 1, wherein the handlebar head set includes a tubular member through which a distal end of the stem is receivable, a lower end face of the tubular member forming a first clutch member, and the outer surface of the stem being provided with a second clutch member complementary to the first and for engagement therewith when the handlebar head set is in either of its first and second configurations.3. A bicycle according to Claim 2, wherein the first and second clutch members have a castellated form with alternate projections and lands on the lower end face of the said tubular member being engageable with corresponding alternate lands and 20 projections on the second clutch member.4. A bicycle according to Claim 3, wherein sides of said projections and lands are tapered to avoid jamming of the first and second clutch members.5. A bicycle according to any of Claims 2, 3 or 4, wherein the stem comprises a conventional stem to which an auxiliary stem piece is fastened, the auxiliary stem 25 piece including a flange with a surface that confronts the lower end face of the tubular member, on which the said second clutch member is formed.6. A bicycle according to any of Claims 2 to 5, wherein the distal end of the stem is threaded to receive a hand-tightenable nut adapted to maintain the first and second clutch members in engagement when tightened.7. A bicycle according to Claim 1, wherein the handlebar head set includes a tubular member through which a distal end of the stem is receivable, a lower end face of the tubular member being provided with a plurality of spaced notches, and the outer surface of the stem being provided with a corresponding plurality of projections to the first and for engagement with the notches when the handlebar head set is in either of its first and second configurations.8. A bicycle according to Claim 7, wherein the stem comprises a conventional stem to which an auxiliary stem piece is fastened, the auxiliary stem piece including the said plurality of proj ecti on s.9. A bicycle according to Claim 8, wherein the distal end of the stem is threaded to receive a hand-tightenable nut adapted to maintain the projections in engagement with the notches when tightened.10. A bicycle according to any of the preceding Claims, wherein a selectably lockable mechanism is provided to lock the handlebar head set to the stem in said second configuration to prevent the handlebar head set being moved from said second configuration to said first configuration while locked, thereby preventing the bicycle from being ridden until the selectably lockable mechanism is unlocked to allow the handlebar head set to be moved to the first configuration.11. A bicycle according to both Claim 10 and any of Claims 2 -6, wherein the selectably lockable mechanism comprises a locking bolt mounted on the first clutch member, and a cooperating aperture in the second clutch member into which an end of the bolt is received when the selectably lockable mechanism is locked, the locking bolt being spring loaded and key operated, so that the mechanism may be locked simply by manually pushing the locking bolt inwardly against the bias of a spring into the aperture in the second clutch member, and unlocked by the key, whereupon the spring bias operates to push the locking bolt outwardly to release it from the aperture in the second clutch member.12. A bicycle according to both Claim 10 and any of Claims 2 -6, wherein the selectably lockable mechanism comprises a padlock, and respective apertured lugs extend outwardly from each of the clutch members, the apertures being aligned when the handlebar head set is in the second configuration, and the shackle of the padlock is passed through both apertures and locked.13. A method of converting a front set of a bicycle from one of a first configuration for normal riding and steering and a second configuration adapted for storage of the bicycle to the other, without need for tools and without the need for realignment of the front wheel and handlebars after movement to said first configuration, the method comprising the steps of: disengaging a first clutch member formed on a lower end face of a tubular member of a handlebar head set from a second clutch member formed on a flange 5 formed on the outer surface of a stem received in the tubular member, the stem being rotatable within a head tube of a frame of the bicycle for steering; rotating said tubular member about the axis of the stem by the angle, preferably 900, between the first and second configurations, and re-engaging said first clutch member with said second clutch member.14. A method according to Claim 13, wherein the first and second clutch members are maintained in engagement with each other in said first and second configurations by a hand-tightenable nut threadedly engaged with the distal end of the stem, the method further comprising a preliminary step of loosening or removing the handtightenable nut sufficiently to allow lifting of said tubular member in the axial direction of the stem sufficiently to disengage the first clutch member from the second clutch member, and a re-engagement step of lowering said tubular member relative to the stem in the axial direction thereof to re-engage the first and second clutch members, and replacing or tightening the hand-tightenable nut to maintain re-engagement.15. A method of converting a front set of a bicycle from one of a first configuration for normal riding and steering and a second configuration adapted for storage of the bicycle to the other, without need for tools and without the need for realignment of the front wheel and handlebars after movement to said first configuration, the method comprising the steps of: disengaging a plurality of notches formed on a lower end face of a tubular member of a handlebar head set from a corresponding plurality of projections formed on the outer surface of a stem or on the outer surface of an auxiliary stem piece attached to a stem received in the tubular member, the stem being rotatable within a head tube of a frame of the bicycle for steering; rotating said tubular member about the axis of the stem by the angle, preferably 90°, between the first and second configurations and re-engaging the plurality of notches with the plurality of projections.16 A method according to Claim 15, wherein the plurality of notches and the plurality of projections are maintained in engagement with each other in said first and second configurations by a hand-tightenable nut threadedly engaged with the distal 5 end of the stem, the method further comprising a preliminary step of loosening or removing the hand-tightenable nut sufficiently to allow lifting of said tubular member in the axial direction of the stem sufficiently to disengage the notches from the projections, and a re-engagement step of lowering said tubular member relative to the stem in the axial direction thereof to re-engage the plurality of notches with the 10 plurality of projections, and replacing or tightening the hand-tightenable nut to maintain re-engagement.