Studio or exercise cycles are used for fitness work at home or within gymnasiums or specialised centres. The cycles are becoming increasingly popular for group workout classes.

Studio or exercise cycles generally include a flywheel which is rotated by the pedalling of a cyclist in a similar manner to a conventional bicycle. It is necessary that the resistance against rotation of the flywheel is variable. This ensures that the cycles are suitable for a wide range of different cyclists and allows individual cyclists to alter the resistance during a session or over time as their fitness improves. It is also desirable that such cycles are provided with brakes for quickly stopping the rotation of the flywheel in an emergency situation. The resistance and braking mechanisms may include felt pads which are forced against the flywheel to a varying degree depending on the level of resistance or braking required.

According to the invention there is provided a resistance adjusting apparatus including: a braking mechanism having a braking force dependent upon tension in a cable; and an activation unit including means for altering the braking force by altering the length of a path followed by the cable and thereby altering the tension in the cable.

The apparatus may be for a cycle, and is preferably for an exercise cycle.

The activation unit may be mountable on or near the handlebars of the cycle. The braking mechanism may be mountable such that it can apply a frictional force to a rotatable member, which may be a flywheel or a wheel of the cycle. The braking mechanism may include pads, which may be felt pads, for applying the frictional force to the wheel. Preferably increasing the tension in the cable increases the frictional force applied by the braking mechanism.

Preferably when the apparatus is in use, the cable path runs substantially from the activation unit to the braking mechanism.

Preferably the cable passes through first and second guides and the means for altering the cable path length includes means for altering the length of the cable path between these guides. Preferably these means include means for altering the curvature of the cable path between the two guides.

The cable may be held within the first guide such that it cannot move through the first guide. The first guide may be associated with the activation unit, and preferably lies within the activation unit. The first guide may prevent movement of the held part of the cable towards the braking mechanism.

The cable may be movable through the second guide. The second guide may be near or on the braking mechanism.

The cable may be located at least partly within a sheath. Preferably the sheath is made of a substantially non-compressible material, which may be steel. The sheath preferably surrounds and is substantially co-axial with the cable. The sheath preferably extends in use substantially from the second guide to the activation unit.

The sheath may abut against the second guide such that the sheath cannot move through or past the second guide.

The activation unit may include mounting means for mounting the unit on a cycle.

The activation unit may include a movable member which, when the activation unit is mounted on the cycle, is movable relative to the cycle. The movable member may include means for holding a part of the sheath, preferably near an end of the sheath, such that the part of the sheath cannot move along its length relative to the movable member. The means for holding the sheath may include means for permitting relative rotational movement between the sheath and the movable member. These means may include a roller bearing.

The movable member may include means for increasing the distance between the part of the sheath held by the movable member and the first guide.

These means may include means for pushing the part of the sheath away from the mounting means, such that the distance between the part of the sheath and the mounting means is increased.

The movable member may be threaded and may be in threaded engagement with a second member. Relative rotation of the movable member and the second member may result in movement of the movable member away from the mounting means. Preferably this results in movement of the part of the sheath held by the movable member away from the first guide. The second member may be in fixed spatial relationship with the mounting means.

The movable member may be internally threaded and the second member externally threaded. The movable member may include a knurled external surface. Both members are preferably hollow, and may be substantially cylindrical.

Preferably the cable may pass through the movable member and the second member, such that the cable may move in its axial direction within the two members. Preferably the first guide is located towards an end of the activation unit remote from the movable member.

The first guide may be movable by brake operation means such as a handle or lever. Preferably the brake operation means may pull the first guide, thereby pulling the cable and activating the braking mechanism.

Preferably the brake operator means may be operated independently of the movement of the movable member. Preferably once operated, the brake operation means remains in the operated position until specifically released.

According to the invention, there is further provided an activation unit for a resistance adjusting mechanism as defined in any of the preceding seventeen paragraphs.

According to the invention there is also provided an exercise cycle including a resistance adjusting apparatus according to any of the preceding definitions.

According to the invention there is further provided a method of altering the resistance of an exercise cycle provided with a resistance adjusting apparatus according to any of the preceding definitions, the method including the step of altering the braking force by altering the length of the path followed by the cable while the cycle is in use.

Preferably the path length is altered while a wheel or flywheel of the cycle is in motion.

An embodiment of the invention will now be described for the purpose of illustration only with reference to the accompanying drawings in which: Fig. 1 is a diagrammatic side view of an exercise cycle fitted with a resistance adjuster according to the invention; Fig. 2A is a diagrammatic side view of a brake mechanism for a resistance adjuster according to the invention; Fig. 2B is a diagrammatic section of an activation unit according to the invention, suitable for use with the brake mechanism of Fig. 2A.

Fig. 3 is a diagrammatic side view of the activation unit of Fig. 2A, with the resistance adjustment fully on; Fig. 4 is a diagrammatic side view of the activation unit of Fig. 2A with the resistance adjustment fully off; Fig. 5 is a diagrammatic exploded side view showing the components of the activation unit of Figs. 3 and 4; and Fig. 6 is a diagrammatic side view of the activation unit of the Figures, with the emergency brake applied.

Referring to Figs. 1 and 2, an exercise cycle 10 includes a flywheel 12 which is rotated by the pedalling of a cyclist. A resistance adjuster 14 mounted on the cycle can be used to bring the flywheel to a quick halt (braking) or to alter the level of effort required to rotate the flywheel and hence the pedals (to alter the resistance).

Referring to Fig. 2A, the resistance adjuster 14 includes a braking mechanism 15 which includes felt pads 16a, b located one on each side of the flywheel 12. A first one of the felt pads 16a is mounted on a first member 18 and a second one of the felt pads 16b is mounted on a second member 20. The two members 18,20 are pivotally attached to one another and to the cycle 10 at an attachment point 22.

The braking mechanism 15 is activated by a brake cable 24 consisting of an inner cable 26 and an outer sheath 28. The inner cable 26 is made of a metallic wire, strong in tension. The outer sheath 28 is also metallic and is strong in compression. The inner cable 26 is attached to an end 29 of an arm 30 of the first member 18. The outer sheath 28 abuts against an end 31 of an arm 32 of the second member 20.

The brake is applied by a remote handle which applies a tensile force to the inner cable 26 while holding firm the outer sheath 28. This forces the arms 30,32 closer together thus pivoting the two members 18,20 about their attachment 22 and forcing the pads 16a, 16b towards each other. This brings the pads 16a, 16b into contact with the flywheel 12 and applies a frictional force to the flywheel thus bringing it to a halt.

In the apparatus according to the invention, the braking mechanism 15 is activated by an activation unit 34, shown in Fig. 2B. This unit is able to adjust the resistance of the cycle, in addition to and independently of the application of the brake, as hereinafter described in detail.

Referring also to Figs. 3 to 6, the activation unit 34 is mountable on the handlebars of a cycle 10 via a leg 36. The inner cable 26 of the brake cable 24 passes freely through the activation unit 34 (see Fig. 2B) and is received and gripped approximately at point 52 in Fig. 2 by a handle 38 (by means not shown in the drawings). Pulling of the handle puts the inner cable under tension. The inner cable 26 may move in its axial direction within the activation unit 34 when it is pulled by the handle 38.

An end 39 of the outer sheath 28 of the cable 24 is received and held within an end of the activation unit 34 remote from the handle 38. The outer sheath 28 is unable to move in an axial direction relative to this end of the activation unit 34.

The brake cable 24 follows a curved path from the braking mechanism to the activation unit, a small part of the path being schematically indicated in Fig.

2A by the numeral 40.

When a cyclist pulls down on the handle 38, the inner cable 26 is put under tension. If the inner cable were not surrounded by the outer sheath 28, the tension in the inner cable would simply cause it to straighten. However, the non-compressible outer sheath 28 abuts against the end 31 of the arm 32 and is also held firmly at its end 39 within the activation unit 34. Thus the path of the outer sheath 28 between these two points cannot straighten. The inner cable 26 is held within the outer sheath 28 and is thus constrained to continue to follow the path 40. The tension in the inner cable 26 and compressive force in the outer cable 28 causes the ends 29,31 of the arms 30,32 respectively to be brought closer together. This applies the brake as previously described.

With a conventional handle operated braking mechanism, as soon as the cyclist releases the handle, it springs back into the position shown in Fig. 3, thus releasing the brake. For an exercise cycle this can allow the flywheel to continue to rotate and is potentially dangerous. In the activation unit 34 according to the invention, a catch mechanism (not shown) is provided to keep the handle 38 in its braking position until it is deliberately released.

The activation unit 34 may also be used to increase the resistance of the cycle as follows. The unit 34 includes a tensioner 41 (see Fig. 5) which is attached to the outer sheath 28 of the brake cable 24. The tensioner 41 is mounted in a radial ball bearing 42 which is mounted within a thumbscrew adjuster 44. The bearing 42 allows the relative rotation of the thumbscrew adjuster 44 and the outer sheath 28.

The thumbscrew adjuster 44 is internally threaded, and is in threaded engagement with an externally threaded hollow substantially cylindrical member 46. The member 46 is fixed to the handle 38 which in turn is mounted via the leg 36 on the cycle handlebars. Thus, the member 46 cannot move relative to the cycle.

The thumbscrew adjuster 44 has a knurled external surface such that it may be easily rotated by the cyclist. When the thumbscrew adjuster 44 is rotated anti-clockwise as viewed from the direction of the brake cable in the drawings, it moves away from the handle 38 because of the action of the screw thread. This pushes the outer sheath 28 of the brake cable away from the handle 38. Because the outer sheath 28 is non-compressible, and abuts against the end 31 of the arm 32, when the outer sheath 28 is pushed away from the handle 38 it is forced to follow a path 50 a small part of which is illustrated schematically in Fig. 2A.

The inner cable 26 is retained inside the outer sheath 28 and is thus also forced to follow the path 50. This increases the distance along the inner cable between the point of the inner cable held by the handle 38 (at approximately point 52 in Fig. 2B) and the end 31 of the arm 32. The inner cable is put under tension by this increase in its cable path length, and resists this increase in path length. This increases the compressive force on the outer sheath 28.

Thus, movement of the thumbscrew adjuster anti-clockwise increases the tension in the inner cable 26 and increases the compressive force in the outer sheath 28. The tension in the inner cable 26 applies a force to the end 29 of the arm 30 in the direction of the arrow A in Fig. 2A while the compressive force in the outer sheath 28 applies a force to the end 31 of the arm 32 in the direction of the arrow B in Fig. 2A. The ends 29,31 of the arms are thus drawn together, causing the members 18,20 to pivot about the attachment 22, bringing the felt pads 16a, 16b into contact with the flywheel. The frictional force applied by the pads 16a, 16b to the flywheel is dependent upon the tension in the inner cable 26 and the compressive force in the outer cable 28.

The level of the braking force depends upon the extent to which the held end 39 of the outer sheath 28 is pushed away from the gripped end of the inner cable, at point 52, thus putting the inner cable 26 in tension and the outer sheath 28 under compression. The braking resistance of the cycle can therefore be altered by rotating the thumbscrew adjuster 44 to vary the extent of overlap of the thumbscrew adjuster 44 and the cylindrical member 46.

In Fig. 3, the thumbscrew adjuster 44 has been rotated until it is as far to the left (as viewed in the drawing) as it can go. This adds an additional length C to the path of the inner cable 26 between the point 52 and the end 31 of the arm 32. This therefore provides a strong breaking force and a strong resistance to cycling.

In Fig. 4, the thumbscrew adjuster 44 has been rotated as far to the right (as viewed in the drawing) as it can go and is in full engagement with the member 46. This applies no breaking force and the flywheel can thus rotate freely.

By rotating the thumbscrew 44, a cyclist can therefore achieve precisely the level of resistance required, completely independently of the operation of the emergency brake by the handle 38.

There is thus provided a combined brake and resistance adjuster for a cycle, the adjuster being simple and safe to operate.

Various modifications may be made to the above without departing from the scope of the invention. A lever handle need not be used to apply tension to the inner cable for application of the brake. Any means of applying such tension may be used. A thumbscrew need not be used to adjust the force applied to the outer sheath, although a threaded connection is desirable, providing a strong connection and a continuos means of adjustment. The braking mechanism illustrated in the Figures need not be used. Any mechanism dependent upon tension in a cable may be adapted for use with the invention.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.