Patent Description:
In microgravity, appearing in space, human muscles are in the slack state all the time, which accelerates muscular atrophy. Therefore, astronauts and space tourists need to exercise when they are on a mission or traveling in space for an extended period of time.

Earth-bound exercise apparatuses usually apply actual weights to provide resistance for the user. However, in microgravity it is necessary to obtain the resistance in other ways such as by means of stretchable cords, pneumatic cylinders, electric brakes, torque bands, etc..

A multifunctional exercise apparatus is disclosed in <CIT>, which uses a pneumatic actuated resistance mechanism. The user interacts with the apparatus by grasping a bar connected to the pneumatic actuated resistance mechanism. In an alternative invention, disclosed in <CIT>, the resistance mechanism is an electric resistance mechanism selected from a group consisting of a linear actuator brake, a linear actuator electromechanical brake, a linear actuator friction disc brake, a stepper motor brake, a servo motor brake, a servo motor electromagnetic brake, a servo motor friction disc brake, and an electric particle brake. <CIT> discloses a multifunctional exercise apparatus comprising a pulling rope connected to a flywheel providing variable and selectable resistance via an adjusting button.

Due to weight and space constraints, only a limited number of exercise apparatuses can be brought onboard a spaceship. Furthermore, some of the known resistance mechanisms have very large sizes and masses. Thus, astronauts and space tourists face a very limited choice of exercise apparatuses, and exercises, when in space.

It is an object of the present invention to provide an improved flywheel arrangement for a multifunctional exercise apparatus. The foregoing and other objects are achieved by the features of the independent claim. Further implementation forms are apparent from the dependent claims, the description, and the figures.

The invention relates to a flywheel arrangement for a multifunctional exercise apparatus, the flywheel arrangement comprising a flywheel rotatably positioned in a housing, a braking band arranged around a portion of the perimeter of the flywheel, and a tension adjusting mechanism comprising a moveable tension arm capable of adjusting the tension of the braking band and an electrical motor for operating the moveable tension arm, wherein the tension adjusting mechanism further comprises a knob for manual manipulation of the moveable tension arm, and a selector for enabling a user in a first position to operate the moveable tension arm with the electrical motor and in a second position to operate the moveable tension arm with the knob.

Normally, the selector is in the first position to allow the electrical motor to operate the moveable tension arm. However, in case of power loss, failure of the electrical motor, or failure in the electronics controlling the regulation the electrical motor can no longer adjust the tension of the braking band. The present invention offers a contingency mode in case the electric regulation system can no longer be used for adjusting the workload. The contingency system works by pushing the selector into the second position, thereby allowing the manual manipulation of the knob to operate the moveable tension arm and thus the adjustment of the braking band.

In an embodiment of the invention, a midsection of the movable tension arm is turnably attached to the housing, an end section of the moveable tension arm is tensioning the braking band, and the other end section is caused to move by the rotation of a tension arm shaft. The design of the movable tension arm allows for a longer travel distance and a higher pull force on the braking band. Furthermore, this design allows only one movable tension arm to be used while still having full manual knob capability.

In an implementation of the invention, the tension arm shaft is rotated by the electrical motor which is a stepper motor. A force sensor may measure how hard the stepper motor is pulling on the braking band whereas another force sensor measures the actual braking torque on the flywheel. The sensor data will be used by the stepper motor to adjust intensity level for, e.g., cycling, rowing and rope pulling.

The revolutions of the stepper motor axle may be transferred to a movement of the movable tension arm by fixing one end of the movable tension arm on a sled and providing a nut on the sled. When a threaded axle of the stepper motor is engaged in the nut, the tension of the braking band may be adjusted by the action of the stepper motor.

In some embodiments of the invention the knob is mounted on the tension arm shaft. In a preferred embodiment, the manual knob is engaged with the tension arm shaft by sliding of a floating shaft.

Suitably, the floating shaft is provided with gears at each end capable of meshing with a gear connected to the manual knob at one end of the floating shaft and a gear positioned on the tension arm shaft at the other end of the floating shaft. The use of a floating shaft prevents the manual knob from being turned by the stepper motor when it is not desired. When the selector is in the second position, the manual knob engages directly with the tension arm shaft via the floating shaft. When the selector is in the second position the manual knob will be disengaged and will not be turned by the stepper motor.

In a preferred implementation of the invention, the floating shaft is operated by the selector, the selector being a manual knob slider. The manual knob slider is preferably positioned on the outside of the housing for easy manipulation by a user. The manual knob slider has attached an arm protruding into the housing ending in a fork capable of engaging with a recess on the floating shaft for moving the shaft in dependence of the position chosen.

In a preferred aspect, the two gears on the floating shaft are slightly unaligned relative to the gear connected to the manual knob and the gear positioned on the tension arm shaft, so that one gear set meshes before the other. The slight misalignment eases meshing as it occurs in two steps.

In an embodiment of the invention, the flywheel comprises a planetary gearing. The planetary gearing achieves a desired inertia while keeping flywheel mass and size down. Preferably, all gears are stainless steel gears.

Preferably, the spokes of the flywheel are configured to act as a fan. The function of a fan may be obtained by making the spokes have a height of about the same as the rim of the flywheel. Furthermore, a fan-action may be obtained by angulation of the spokes. Preferably, the spokes that are angled to assist in dissipation of heat from the flywheel is now acting as a fan. The fan is preferably pulling cold air in from the electronics side and blowing it out through the front of the module.

In an embodiment of the invention, the perimeter of the flywheel is provided with teeth for allowing a speed sensor to measure the velocity. The sensor can be adjusted to emit a pulse every time a tooth passes the read head. The sensor data may be used for adapting the tension of the flywheel.

These and other aspects will be apparent from the embodiments described below.

<FIG> discloses a multifunctional exercise apparatus in its first position, i.e. in a position in which the force experienced by the user of the apparatus is obtained by the combined effect of a torque resistance mechanism <NUM> and a flywheel <NUM>. A first module <NUM> of the multifunctional exercise apparatus has an essentially box shape with rounded corners. <FIG> discloses the first module <NUM> with a removed lid for showing a cable reel system <NUM>. The cable reel system <NUM> is operably connected to the torque resistance mechanism <NUM> that provides resistance when a cable <NUM> of the cable reel system <NUM> is pulled and that returns the cable <NUM> to a wound position on one of cable reels <NUM>,<NUM> when the cable <NUM> is not pulled.

The multifunctional exercise apparatus furthermore comprises a second module <NUM>. The second module <NUM> has an essentially box shape with slightly rounded corners. In <FIG>, the lid of the second module has been removed to show the flywheel <NUM> contained within the box shaped module. Around a part of the perimeter of the flywheel <NUM>, a braking band <NUM> is positioned for providing resistance to the inertia produced by the flywheel <NUM>.

The first <NUM> and the second <NUM> modules can be arranged in at least two different positions as shown in <FIG> and <FIG>, respectively. <FIG> shows a first position in which the torque resistance mechanism <NUM> of the first module <NUM> is operably connected to the flywheel <NUM> positioned in the second module <NUM>, i.e. the second module <NUM> is positioned on top of the first module <NUM>. <FIG> shows a second position for the first <NUM> and second <NUM> modules in which the torque resistance mechanism <NUM> of the first module can be operated independently of the action of the flywheel <NUM> of the second module <NUM> when a user pulls a cable <NUM> of the cable reel system <NUM>.

The connection of the torque resistance mechanism <NUM> with the flywheel <NUM> may be performed by providing the torque resistance mechanism <NUM> with a first part of a coupling mechanism such as a hub <NUM> and the flywheel <NUM> with a second part of the coupling mechanism, such as a hub <NUM>, whereby the hubs <NUM>, <NUM> are positioned coaxially when the modules are in the first position for enabling an operable connection when an axle such as shaft <NUM> is provided in the hubs <NUM>, <NUM>.

The first module <NUM> and the second module <NUM> are connected along an edge of each of the modules by a hinge <NUM>. The hinge <NUM> allows the first <NUM> and the second <NUM> modules to be moved relative to each other so as to obtain the first and second positions. The hinge <NUM> is a double hinge allowing a major surface of the first module <NUM> to extend flush with a major surface of the second module <NUM>, thereby providing a platform for the user to, e.g., stand on. The double hinge includes two pivot joints <NUM> for pivoting the second module <NUM> to different positions relative to the first module <NUM>. A handle <NUM> is provided for assisting the user in positioning the second module <NUM> in the desired position. The hinge <NUM> may be locked in a certain position to maintain the desired position of the modules <NUM>, <NUM> during an exercise.

<FIG> discloses a third position of the first <NUM> and second <NUM> modules relative to each other. In the third position, a main extent of the first module <NUM>, i.e. the surface pointing vertically upwards in <FIG>, is perpendicular to a main extent of the second module <NUM>. The hub <NUM> of the second module <NUM> is provided with a through-going splined axle <NUM> fitted with pedal arms <NUM> and pedals <NUM> at each end when the first <NUM> and second <NUM> modules are in the third position. The pedal arms <NUM> are provided with snap locks <NUM> for fast and efficient mounting and dismounting of the equipment necessary for performing a cycling exercise.

The second module <NUM> is provided with engaging means <NUM> for accommodating a seat post <NUM>. Optionally, a second engaging means may be positioned on the hinge <NUM> for allowing the seat post <NUM> to be attached at two positions in order to obtain higher stability. The seat is provided with a back support <NUM>, the angle of which can be adjusted. Additionally, the back support <NUM> may have <NUM>-<NUM> degrees of spring-loaded flex that can be enabled and disabled. For biking, the seat will be configured as shown in <FIG>. The back support <NUM> will be used in combination with handles <NUM> to achieve a posture similar to a recumbent exercise ergometer. The back support <NUM> may be locked or allowed to flex depending on user preference. The seat post <NUM> comprises a waist strap <NUM> to keep the user down on the seat during exercise at microgravity. For biking, waist strap <NUM> can be used either in combination with, or instead of, handles <NUM>. The inertia of the flywheel <NUM> makes it possible to adjust the workload in a way that feels similar to bicycling on ground.

In one embodiment, the flywheel <NUM> is configured such that it continues to spin while the pedals <NUM> stay stationary when the user stops pedaling. This is possible due to a one-way bearing connecting the flywheel <NUM> to the axle <NUM>.

For rowing, when the modules are in the first position, the back support <NUM> will generally be positioned in a more upright position. The spring-loaded flex of the back support <NUM> will provide the user with tactile feedback that they should not extend further when they feel the seat without hitting a "rigid wall". In rowing, the waist strap <NUM> is a necessity since the force from the cable <NUM> will generate a rotation away from the seat.

The seat is mounted on a carriage <NUM> that can slide on an inner tube <NUM> of the seat post <NUM> to allow the user to perform the rowing exercise. The sliding function can be locked in a top position when the apparatus is used for the cycling exercise. The inner tube <NUM> can be adjusted freely in an outer tube <NUM> and locked in any position with a snap lock <NUM> on the outer tube <NUM>.

<FIG> show the multifunctional exercise apparatus configured in the cycling mode. The user initially is positioned in the seat by securing the strap <NUM> around the waist. Subsequently, cycling shoes (not showed) having clamps corresponding to the pedal locking system are clicked into the pedals <NUM>.

<FIG> shows the multifunctional exercise apparatus configured in the rowing mode. For rowing, separate footplates <NUM> are installed. These footplates <NUM> are needed for foot fixation and to achieve a suitable geometry, where the feet are below the seat and below the cable <NUM> exit points, i.e. the points where cables <NUM> exit the first module housing and the frame <NUM> such that the user can grasp them. The footplates <NUM> also angle the feet correctly and they allow the user to bend his/her toes without falling out of the feet fixation. The frame <NUM>, extending from the first module <NUM> and serving as support for the second module <NUM> in other configurations, is provided with a swivel <NUM>. Similarly, the platform, formed by the first <NUM> and second <NUM> modules when arranged in the second position, is provided with a swivel <NUM>. The cable <NUM>, attached to a rowing handle <NUM> at one end, is guided by the swivels <NUM> to the cable reel system <NUM> which is operably connected to the torque resistance mechanism <NUM>. When the user pulls at the rowing handle <NUM>, he/she will experience the combined forces exerted by the torque resistance mechanism <NUM> and the flywheel <NUM> with brake <NUM>.

When performing resistive exercises, the user can choose to use both cables <NUM> exiting from the sides of the platform formed by the first <NUM> and second <NUM> modules when arranged in the second position. This will typically be done with a wide bar <NUM> used for heavy exercises such as squat, bench press, and deadlift. It can also be used for bicep curls and other lighter exercises if desired. The "dual rope mode" is illustrated in <FIG> with the squat exercise as an example. The swivels <NUM> are positioned at each end of the platform formed by the upper surface of the first module <NUM> arranged flush with the upper surface of the second module <NUM>. Each cable <NUM> from the cable reel system <NUM> is guided by the swivels <NUM> to a specific add-on selected by the user. In <FIG>, the user has selected a wide bar <NUM> connected to slack lines <NUM> at each end. The slack lines <NUM> are safer when the wide bar <NUM> is used for "under bar" exercises, i.e. exercises where the user has placed his/her body underneath the bar or handle. The slackline <NUM> is a piece of rope installed between the handle and a mechanical end stop <NUM> provided at an end of cable <NUM>. This extra rope can never be pulled into the machine and acts as a safety feature for the user. It works by ensuring that the user cannot be forced into a dangerous position between the handle/bar and the platform, i.e. when a squat is performed the slack line <NUM> stops the machine from pulling the handle/bar lower than the lowest position of the squat. The slack lines <NUM> also make it easier for the user to achieve a better position for initiating certain exercises. The slack line <NUM> has a number of rubber sleeves <NUM> arranged around it to stiffen the rope slightly with alternating loops <NUM> between the rubber sleeves <NUM> for allowing the end of the handle/bar to engage with the slack line <NUM>. During the squat exercise, the forces exerted by the torque resistance mechanism <NUM> are experienced by the user and not the flywheel <NUM>.

The swivel <NUM> allows the cable <NUM> to be pulled in any direction within a semi-sphere with its origin in the swivel <NUM>. This flexibility makes it possible to use a wide range of add-ons, including a single hand handle for exercises using a single cable <NUM>, such as triceps extensions, twisting exercises, or other asymmetrical exercises. To use one cable <NUM>, the other cable <NUM> is simply left untouched at its end stop. A single hand handle is then attached to the single cable end stop <NUM>. A slack line <NUM> is generally not needed since the user cannot get caught under the handle.

Instead of using the main cable exit points, the swivels <NUM> can also be attached to further attachment points on the exercise unit. The handle can then be connected to the cable end stop <NUM> as described above. This way, the cable is now in "Single Rope" mode but extending from a different position on the platform.

<FIG> show a rope pulling unit <NUM> for connection with the flywheel <NUM> in the second module <NUM>. The rope pulling unit <NUM> contains an endless rope <NUM>. This rope <NUM> is driving an axle mounted in the hub <NUM> of the second module <NUM>. Thus, the rope <NUM> will pull the flywheel <NUM> into motion with the possibility to do hand over hand pulling. The rope pulling unit <NUM> will preferably have a pulley <NUM> slidingly mounted on the rope <NUM> and be used for fixing a section of the endless rope <NUM> to the platform. Furthermore, the pulley <NUM> is adapted for the thicker rope usually used for rope pulling. The rope pulling unit <NUM> is releasably attached to the second module <NUM> by turning bolts <NUM>. The head of the bolt <NUM> has a size and form easy for the human hand to manipulate.

The resistance of the endless rope <NUM> is adjusted by the braking band <NUM>. As opposed to the finite cable stroke used in rowing, the rope <NUM> in the rope pulling add-on is endless (a closed loop) and can be pulled an "infinite" amount. The rope <NUM> is guided to a center attachment point by the pulley <NUM>.

<FIG> show the cable reel system <NUM>. An upper cable reel <NUM> facing the second module <NUM> and a lower cable reel <NUM> facing the torque resistance mechanism <NUM> are both provided, on their outer circumference, with grooves <NUM> for accommodating a cable <NUM>. On a side of the upper cable reel <NUM> facing the lower cable reel <NUM>, a ring gear <NUM> is provided, and on a side of the lower cable reel <NUM> facing the upper cable reel <NUM> another ring gear <NUM> is provided. The upper and lower cable reels <NUM>, <NUM> are rotatably journaled on a shaft <NUM>. Between the upper <NUM> and the lower <NUM> cable reels, the shaft <NUM> is provided with four carriers <NUM> extending in the radial direction from the shaft <NUM> center axis. In the upper end of the carriers <NUM>, pinion gears <NUM> are rotatably journaled and configured to mesh with both of the two ring gears <NUM>, <NUM>. While the four pinion gears <NUM> each rotate freely around their respective axis, they also follow the rotation of the shaft <NUM>. Thus, if the shaft <NUM> is stationary and one reel <NUM>, <NUM> is rotated clockwise, then the other reel <NUM>, <NUM> will rotate counterclockwise. If one reel <NUM>, <NUM> is stationary, the other reel <NUM>, <NUM> will follow the rotation of the shaft <NUM> and hub <NUM>. The moving reel will move twice as fast as the shaft <NUM> and hub <NUM> though. If both reels <NUM>,<NUM> are moved at the same speed, then the shaft <NUM> and hub <NUM> will follow their rotation <NUM>:<NUM>. As a result of this mechanism, the torque on the shaft <NUM> will always be divided equally between each reel <NUM>, <NUM>.

The upper <NUM> and lower <NUM> cable reels are journaled on the shaft <NUM> using ball bearings <NUM>. The ball bearings <NUM> are of stainless steel using non-contact metal seals. This type of seal keeps the grease in place while providing the least amount of friction.

At the end of the shaft <NUM> that is designed for engagement with the torque resistance mechanism <NUM>, a splined part <NUM> is provided. At the other end of the shaft <NUM>, the hub <NUM> is provided for engagement with a corresponding axle. When the hub <NUM> is not engaged with an axle it may be provided with a cap <NUM>.

<FIG> shows an exploded view of the torque resistance mechanism <NUM>. The electrical torque resistance mechanism <NUM> comprises an electrical torque motor/generator <NUM> comprising a stator <NUM> and a rotor <NUM>. In a hollow space defined by the stator <NUM>, a torsional spring <NUM> is accommodated with the rotor <NUM>. The electrical torque resistance mechanism <NUM> also comprises a part of a coupling mechanism, which may be selected as a hub <NUM> having a cavity <NUM> capable of mating with another part of a coupling mechanism, such as the shaft <NUM> of the cable reel system <NUM>. Generally, the shaft <NUM> is splined, and the hub <NUM> contains complementing grooves for accommodating the shaft <NUM>. The electrical torque resistance mechanism <NUM> also comprises a selector <NUM> capable of being moved to at least two positions. In a first position, illustrated in <FIG>, the coupling mechanism is engaged with the rotor <NUM> of the electrical torque motor/generator <NUM> and in a second position, illustrated in <FIG>, the coupling mechanism is engaged with a spring rotor <NUM> of the torsional spring <NUM>.

The stator <NUM> is attached to a lower part of a first housing <NUM> and the rotor <NUM> is rotatably arranged in the hollow space defined by the essentially annular stator <NUM>. The rotor <NUM> is provided with spokes <NUM> for connecting the rim of the rotor <NUM> with the center of the rotor <NUM>. The center of the rotor <NUM> is provided with a recess <NUM> capable of being engaged with a part of the coupling mechanism, such as the hub <NUM>. The hub <NUM> may be provided on an outer circumference with a plurality of teeth <NUM> or "dog teeth" that mate with matching openings machined or otherwise provided in the recess <NUM> at the center of the rotor <NUM>.

The coupling mechanism is a hub <NUM> capable of being moved in axial direction between a first position for engagement with the electrical torque motor/generator <NUM> and a second position for engagement with the torsional spring <NUM>. When the circumferential teeth <NUM> of the hub <NUM> are engaged with the corresponding recess <NUM> in the rotor center the engagement is locked. However, when a user moves the selector <NUM> it causes the hub <NUM> to move in an axial direction and thereby disengage the connection between the hub <NUM> and the electrical torque motor/generator <NUM>. An upper section of the hub <NUM> is provided with a recessed rosette <NUM> having a shape complementary to the shape of a dog teeth gear <NUM> connected to the spring rotor <NUM> of the torsional spring <NUM>.

The torsional spring <NUM> is positioned in a separate, second spring housing <NUM> mounted rotatably in the first housing <NUM> of the electric torque resistance mechanism <NUM>. <FIG> shows the lid <NUM> of the spring housing <NUM> comprising a not shown pole protruding from the back side of the lid <NUM> for engagement with a hook <NUM>. One end of spiral torsion spring <NUM> is engaged with rotor <NUM>. Thus, when the dog teeth gear <NUM> provided on the spring rotor <NUM> is engaged with the rosette <NUM> of the hub <NUM>, the user can perform exercises using the spiral torsion spring <NUM> as load.

Before the user can use the spiral torsion spring <NUM> as load it needs to be tensioned. The tensioning is performed by rotating the spring housing <NUM>. To help the user twist the spring housing <NUM>, it is provided with handles <NUM> attached to the lid <NUM>. The handles <NUM> are provided with a lock <NUM> for preventing the spring housing <NUM> from spinning back to a relaxed position. After usage, the tensioning of the spiral torsion spring <NUM> may be relaxed by deactivating the lock <NUM>.

A toggle mechanism for moving the hub <NUM> in axial direction between the two positions is shown in detail in <FIG>. The selectors <NUM> protrude through the openings <NUM> in the lid <NUM> of the first housing <NUM> comprising the electrical torque motor/generator <NUM>. The selector <NUM> may be moved between a first position termed "motor" and a second position termed "spring" by the user. When the selector <NUM> is moved, arms <NUM> turn a shift collar <NUM> provided with traces <NUM>. An axially moveable ring <NUM> is provided with radially extending pins <NUM> positioned in the traces <NUM>. Since shift ring columns <NUM> are fixed to the lid <NUM>, the ring <NUM> will move axially when the selector <NUM> is moved between positions. <FIG> shows the second position in which the hub <NUM> is lifted and in which the rosette <NUM> will mesh with the dog teeth gear <NUM> provided on the spring rotor <NUM>. <FIG> shows the first position in which the hub <NUM> is lowered and the circumferential dog teeth <NUM> of the hub <NUM> are caused to mesh with the recess <NUM> of the rotor <NUM> of the electrical torque motor/generator <NUM>.

The rotor <NUM> of the electrical torque motor/generator <NUM> is provided with an optical read head for an encoder <NUM>. For increased serviceability of the encoder, a lid <NUM> is provided. The encoder may be selected as Renishaw RESOLUTE™ absolute encoder with the RESA30 rotary ring provided on the rotor.

The hub <NUM> may be provided with a further engagement mechanism for the second position (not shown).

<FIG> shows a part of the second module <NUM> in an exploded view. The exploded view extracts a tension adjusting mechanism <NUM> from the second module <NUM> and a manual knob slider <NUM> from lid <NUM> of the second module <NUM>. The flywheel <NUM> is rotatably provided in the second module <NUM>. The braking band <NUM> is arranged around a portion of the perimeter of the flywheel <NUM>. The tension adjusting mechanism <NUM> comprises a moveable tension arm <NUM> capable of adjusting the tension of the braking band <NUM> and an electrical motor <NUM>, e.g. a stepper motor, for operating the moveable arm <NUM>. The tension adjusting mechanism <NUM> comprises a knob <NUM> for manual manipulation of the movable tension arm <NUM>. The tension adjusting mechanism <NUM> also comprises a selector, i.e. manual knob slider <NUM>, for enabling a user in a first position to operate the moveable tension arm <NUM> with the electrical motor <NUM> and in a second position to operate the moveable tension arm <NUM> with the knob <NUM>.

The movable tension arm <NUM> is bended and, in a midsection <NUM>, attached to a housing. One end of the movable tension arm <NUM>, pointing towards the flywheel <NUM>, is provided with a slot <NUM> for guiding and tensioning the braking band <NUM>. The slot <NUM> may be provided with a roller to reduce the resistance between the slot <NUM> and braking band <NUM>. The other end of the movable tension arm <NUM> is caused to move by the rotation of a tension arm shaft <NUM>. The tension arm shaft <NUM> is rotated by the electrical motor <NUM>. The revolutions of the electrical motor axle <NUM> may be transferred to movement of the movable tension arm <NUM> by fixing one end of the movable tension arm <NUM> on a sled <NUM> and providing a nut <NUM> on the sled <NUM>. When the threaded axle <NUM> of the electrical motor <NUM> is engaged in the nut <NUM>, the tension of the braking band <NUM> may be adjusted by the action of the electrical motor <NUM>.

The manual knob <NUM> is provided with an axle having a gear <NUM> at the opposing end of the axle. The gear <NUM> may be engaged with the movable tension arm <NUM> by sliding a floating shaft <NUM> provided with gears <NUM> at each end. <FIG> shows the tension adjusting mechanism <NUM> in the first position, i.e. where the manual manipulation is disengaged, and <FIG> shows the tension adjusting mechanism <NUM> in the second position, i.e. where the knob <NUM> is engaged and has full control of the movable tension arm <NUM> regardless of the position of the electrical motor <NUM>. The two gears <NUM> on the floating shaft <NUM> are slightly unaligned relative to the gear <NUM> connected to the knob <NUM> and a gear <NUM> positioned on the tension arm shaft <NUM>, so that one gear set meshes before the other.

In this embodiment, structures and features that are the same or similar to corresponding structures and features previously described or shown herein are denoted by the same reference numeral as previously used for simplicity.

The various aspects and implementations have been described in conjunction with various embodiments herein. However, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed subject-matter, from a study of the drawings, the disclosure, and the appended claims.

Claim 1:
A flywheel arrangement for a multifunctional exercise apparatus, the flywheel arrangement comprising a flywheel (<NUM>) rotatably positioned in a housing (<NUM>), a braking band (<NUM>) arranged around a portion of the perimeter of the flywheel (<NUM>), and a tension adjusting mechanism (<NUM>) comprising a moveable tension arm (<NUM>) capable of adjusting the tension of the braking band (<NUM>) and an electrical motor (<NUM>) for operating the moveable tension arm (<NUM>),
wherein the tension adjusting mechanism (<NUM>) further comprises a knob (<NUM>) for manual manipulation of the moveable tension arm (<NUM>), and a selector (<NUM>) for enabling a user in a first position to operate the moveable tension arm (<NUM>) with the electrical motor (<NUM>) and in a second position to operate the moveable tension arm (<NUM>) with the knob (<NUM>).