This disclosure relates to cycling resistance apparatuses, more specifically, to cycling resistance apparatuses that use eddy currents to provide resistance.
During the training process for cyclists, or during rehabilitation from injury, cyclists are often required to spend a large amount of time using an “indoor trainer”, i.e., a resistance apparatus designed to simulate load experienced by the cyclist on the road. Resistance apparatuses provide a training environment which allows for off-season, poor weather, and/or controlled exercise.
Some indoor trainers allow the cyclist to use his or her own bicycle for training. These apparatuses generally fall into two categories: those driven by the rear wheel, or main drive wheel of the bicycle, and those driven directly by the drive chain, which requires mounting the bicycle to a dedicated sprocket and stand. Many of these devices have drawbacks that include increased tire wear, loud operating noise levels, difficulty in mounting/dismounting the bicycle from the device, and high cost.
In addition to indoor training, many cyclists ride in outdoor groups for training purposes. As the size of the group increases, the likelihood of riders being either significantly faster or slower than the bulk of the group increases. As a result, these riders may be frustrated by the inability to keep up with the group, or are alternately frustrated by the inability to get a good workout due to the perceived slow pace required to remain with the group. In order to combat this, use of electric assist has been proposed to help slower riders keep pace with faster riders. However, electric assist devices are costly, potentially heavy, can be difficult to install and remove, and often disqualify the use of a bike for competition.
According to an aspect of the present invention, a cycling resistance apparatus includes an adjustment mechanism configured to be attached to a frame, such as a stationary frame or the frame of a bicycle, and a magnet assembly attached to the adjustment mechanism. The adjustment mechanism is configured to position one or more magnets of the magnet assembly at an active position so that a face of each magnet is positioned within a diameter of a bicycle tire and within a width of the bicycle tire, so as to be adjacent an electrically conductive rim of the bicycle wheel. When in the active position, the one or more magnets of the magnet assembly induce eddy currents in the electrically conductive rim of the wheel to provide resistance against rotation of the wheel in the frame.
According to another aspect of the present invention, a cycling resistance apparatus includes an adjustment mechanism configured to be attached to a frame, a wheel of a bicycle being rotatably mounted with respect to the frame. The wheel has an electrically conductive rim, and a tire is mountable to the electrically conductive rim. The apparatus further includes a magnet assembly attached to the adjustment mechanism, the magnet assembly having at least one magnet. The adjustment mechanism is configured to position the at least one magnet of the magnet assembly at an active position configured to induce eddy currents in the electrically conductive rim of the wheel to provide resistance against rotation of the wheel in the frame without requiring any corresponding magnets to be attached to the rim, tire, or wheel of the bicycle.
According to another aspect of the present invention, a cycling resistance apparatus includes an adjustment mechanism configured to be attached to a frame, a wheel of a bicycle being rotatably mounted with respect to the frame. The bicycle has an electrically conductive rotational component as part of the wheel or attached to the wheel. The electrically conductive rotational component is configured for normal operation of the bicycle. The apparatus further includes a magnet assembly attached to the adjustment mechanism, the magnet assembly having at least one magnet. The adjustment mechanism is configured to position the at least one magnet of the magnet assembly at an active position configured to induce eddy currents in the electrically conductive rotational component of the bicycle to provide resistance against rotation of the wheel in the frame without requiring any corresponding magnets to be attached to the rim, tire, or wheel of the bicycle.
The interaction between the magnet assembly and the rotating rim, or other rotational component, results in eddy currents generated within the bicycle rim or other rotational component, and subsequently a reactive force retarding the rotation of the wheel. The nature of the present invention requires no direct contact with the bicycle rim, tire, or wheel, and the retardation force can be manipulated by changing the active position by adjusting magnet proximity to the rim or other rotational component, by selecting the number of magnets used and/or the field strength of the magnets, by controlling the relative speed between the rim or other rotational component and the magnets, in addition to controlling parameters such as the size, shape, and/or composition of the bicycle rim or other rotational component. Suitable bicycle rims and rotational components include those made of steel, copper, aluminum, alloys thereof, and other electrically conductive materials. The invention is applicable to the majority of currently available bicycle rims, which tend to be constructed of extruded aluminum, as well as to many currently available disc brakes, which tend to be made of steel. The power absorbed by the resistance is mainly dissipated through heating of the rim or other rotational component, with heat then being transferred into the surrounding air. Due to lack of direct contact with the bicycle rim or other rotational component, there may be less additional noise generated by the apparatus, there may be no additional tire wear, and construction costs may be reduced due to a lack of moving parts.
Depending on rider preference, additional inertia or “effective inertia” may be required to maintain a substantially constant wheel speed between pedal strokes, thereby moderating the fluctuations in energy dissipation rate, or power, absorbed by the resistance apparatus. Real inertia can be added via mass within the system, such as a flywheel or additional weights added to the wheel and tire assembly. Effective inertia can be created by controlling the eddy current resistance via dynamic manipulation of magnetic field location or orientation or magnetic field strength, which can be performed during a single wheel rotation, a single pedal rotation, or over the course of multiple pedal rotations.
The cycling resistance apparatus can include a stationary frame that supports the bicycle or can be mounted to the frame of the bicycle itself. In the latter case, the apparatus can be provided to the drive wheel or a non-driven wheel. During operation, the apparatus may be adjusted directly by the rider, or by an actuator, so that the desired additional resistance is achieved by manipulating the magnetic interaction with the rotating rim. This allows for outdoor usage in group rides with the effect of “handicapping” faster riders.
These and other aspects of the present invention will be discussed in detail below.
The drawings illustrate, by way of example only, embodiments of the present disclosure.
The wheel 16 of the bicycle 14 has an electrically conductive rim 30, such as a conventional aluminum rim, with a tire 32 mounted to the rim 30 as conventional for normal riding of the bicycle on roads, tracks, or other locations. The rim 30 can be any suitable electrically conductive material, with aluminum, steel, copper, and alloys thereof being examples. The tire 32 need not be mounted to the rim 30 for the apparatus 10 to function.
The cycling resistance apparatus 10 includes an adjustment mechanism 40 attached to the frame and at least one magnet assembly 42 attached to the adjustment mechanism 40. The magnet assembly 42 has at least one magnet. In this embodiment, two opposing magnet assemblies 42 and 44 (hidden in this view; see
The adjustment mechanism 40 is configured to position the magnet assemblies 42, and the magnets carried thereby, at an active position close to the rim 30. When in the active position, the magnet assembly 42 induces eddy currents in the electrically conductive rim 30 of the bicycle wheel 16 to provide resistance against rotation of the wheel 16. Moreover, suitable resistance can be provided by the apparatus 10 without any magnets required to be attached to the rim, tire, or wheel of the bicycle, as is needed in some conventional systems. In other embodiments, the active position is close to another electrically conductive rotational component of the bicycle, such as a rotating disc of a disc brake. In any event, the electrically conductive rotational component of the bicycle, be it a rim, disc, or other component, is a component of the bicycle that is normally part of the bicycle and that is not specifically added to the bicycle for use with the apparatus.
In operation, the rider uses the adjustment mechanism 40 to position the magnet assemblies 42 relative to the rim to set the desired resistance and pedals the bicycle normally, whether using the apparatus with a stationary frame or during an actual ride with the apparatus attached to the bicycle. Control of the adjustment mechanism 40 can be manual, automatically electrically controlled, or some combination of such.
The active position is shown in detail in
As shown in
In this embodiment, the adjustment mechanism 40 further includes a quick release mechanism 70 configured to lock and unlock rotation of the caliper arms 60, 62. For example, a cam-type quick release handle can be used. In other embodiments, the rotation of the caliper arms 60, 62 is controlled by a manual actuator (e.g., a lever, knob, etc.) or an electromechanical actuator, such actuator being directly manually controlled by a rider or controlled by a controller either automatically or under the control of the rider.
Each magnet assembly 42, 44 is connected to a free end of a different caliper arm 60, 62 opposite the end connected to the pivot point 66. The free end is not necessarily the extremity of the caliper arm, as additional length of caliper arm may be provided for various purposes such as to mount a sensor.
The rotation of the caliper arms 60, 62 can be controlled to bring the magnet assembly 42, 44 to their active positions to generate suitable eddy current resistance and to withdraw the magnet assembly 42, 44 away from the rim 30 so as to provide clearance to easily remove the wheel 16 (at its widest point, e.g., the tire) from the apparatus 10. The quick release mechanism 70 allows for easy manual adjustment of the active position to customize the degree of eddy current resistance provided. In other embodiments, controller-actuated adjustments can be used to dynamically modify the degree of eddy current resistance.
As can be seen, the mounting component 68 connects the load cell 64 and attached caliper arms 60, 62 to a support leg 80 of the frame 12. In this embodiment, the mounting component 68 includes a flat plate that is welded to the support leg 80 and that includes a linear slot 82 for receiving and guiding a pair of screws 84 or similar structure threaded into or otherwise attached to the body of the load cell 64. The screws 84 connect the load cell body to the mounting component 68 and provide linear adjustable positioning of the pair of caliper arms 60, 62 with respect to apparatus 10 and thus the bicycle wheel. That is, the screws 84 can be loosened to allow the linear position X of the caliper arms 60, 62 to be adjusted before being tightened to fix the caliper arms 60, 62 in position. This can allow the apparatus 10 to accommodate different wheel diameters. Other fastening techniques to facilitate sliding within the slotted plate or other mounting component 68 are contemplated. In other embodiments, a simple non-load-sensing beam or similar mounting structure that retains a generally fixed mounting point is used instead of a load cell.
Further, in this embodiment, each magnet assembly 42, 44 include a magnet holder 90 that is rotatably connected to the free end of the respective caliper arm 60, 62 at a respective pivot point 86, which can be defined by a screw, bolt, pin, or similar structure. This allows the magnet assemblies 42, 44 to accommodate various wheel styles and/or to swivel from the active position to a compact storage position (see
Each magnet holder 90 holds a plurality of magnets 52. Magnets 52 can be affixed to the magnet holders 90 by fastening features, such as clips, indents, interference fits, screws, clamps, or similar or by permanent techniques, such as thermal bonding, adhesive, or similar. In this embodiment, the magnets 52 are individually removably connected to the magnet holders 90 in order to permit addition and removal of magnets 52 so that resistance can be further customized.
In addition, in this embodiment, the magnets 52 of each magnet assembly 42, 44 are arranged in an arc having a diameter consistent with the diameter D of the electrically conductive rim 30. That is, the diameter of the arcuate path on which the magnets 52 are arranged is selected to accommodate the expected diameter or diameter range of bicycle rims to be used with the apparatus 10. This arc-shaped arrangement of magnets advantageously increases the maximum possible eddy current resistance that can be generated by the apparatus and keeps the overall apparatus compact with respect to conventional systems. In other embodiments, other magnet arrangements, such as linear arrangements, can be used. Moreover, when used with a rotational component of smaller diameter, such as a disc brake, the arrangement of magnets can follow a correspondingly tighter arc.
Each collapsible support leg 100 is rotatably connected to one of the fixed support legs 80 at an upper end of the fixed support leg 80. This pivot connection is made by a bolt 104 that extends through holes provided in the upper ends of the fixed support leg 80 and the collapsible support leg 100. In other embodiments, other structures can be used to provide the rotatable connection of the collapsible support leg 100 to the fixed support leg 80.
To facilitate compact collapse of the stationary frame 12 for storage, each collapsible support leg 100 is shaped to sheath the respective fixed support leg 80. That is, the collapsible support leg 100 defines an internal volume 106 that accommodates at least a portion of the fixed support leg 80. In this embodiment, the legs 80, 100 are made from round metal tubing, with the collapsible support legs 100 having a larger diameter than the fixed support legs 80. In other embodiments, other shapes of tubing (e.g., rectangular) can be used. Further, the tubing of each collapsible support leg 100 is cut away on a cut line 108 that can follow any suitable path, so as to create an opening to the internal volume 106 of the collapsible support leg 100. The cut line 108 extends longitudinally along the collapsible support leg 100 to open the internal volume 106. The cut line 108 may have a circumferential component, as shown, to remove excess material that may cause pinch points when the frame 12 is collapsed, while leaving enough material to provide suitable strength for the collapsible support leg 100.
An abutting portion 110 of each collapsible support leg 100 defines the extent of rotation of the collapsible support leg 100 with respect to the fixed support leg 80. A stopper portion 112 located at an upper end of each collapsible support leg 100 and opposite the abutting portion 110 provides increased resistance to over-rotation of the collapsible support leg 100. The lower end 114 of the collapsible support leg 100 is left with a full diameter of tube for strength against local deformation.
Referring back to
Detail of a magnet assembly 42, 44 according to this embodiment is shown in
The cycling resistance apparatus 200 includes a mounting clamp 202 that clamps to the bicycle frame 204 to position an adjustment mechanism 206 and the magnet assemblies 42, 44 relative to one of the bicycle wheels, not necessarily the drive wheel. The principles of operation and adjustment are the same as described above. The rider may adjust the resistance during a ride by manually actuating the adjustment mechanism 206, which can include a quick release mechanism 70 or similar. In other embodiments, the apparatus is additionally or alternatively configured for controller-actuated adjustments to dynamically modify the degree of eddy current resistance. Addition and removal of magnets is also an option to vary resistance. Further detail of the cycling resistance apparatus 200 is shown in
With reference back to
As shown in
In this embodiment, the weight 300 includes a central planar portion 310 sandwiched between two side portions 312, 314. One side portion 312, is generally U-shaped to accommodate a spoke centrally aligned with the weight 300. The opposite side portion 314 has a shape that is generally complementary to the side portion 312 to accommodate two spokes adjacent the central spoke and tilted differently from the central spoke. The central planar portion 310 of the weight is circumferentially longer than the two side portions 312, 314. In this embodiment, the weight 300 is a single monolithic piece of material as opposed to several pieces of material that are bolted or otherwise connected together. Further, in some embodiments, the weight 300 is made of non-magnetic material to avoid interaction with the magnets of the apparatus 10. In still other embodiments, the weight 300 is made of magnetic material (e.g., carbon steel, etc.) and the weight 300 is positioned further from the rim 30 or other rotational component to avoid interaction with the magnets of the apparatus 10.
In some embodiments, the weight 300 incudes one or more notches 316 to accommodate spokes. Further, in some embodiments, the weight 300 includes at least one threaded hole 318 to receive a screw to provide a clamping load between the weight 300 and at least one spoke of the wheel to hold the weight 300 in place. Further, in some embodiments, the weight 300 includes protrusions 320 to offset the weight 300 from the rim 30 of the wheel.
The adjustment mechanism 40 includes a pair of caliper arms 60, 62 that are pivotably driven by an actuator 402, such as a stepper motor, that is connected to the frame 12 via the load cell 64 or other member. Another actuator 404, such as a stepper motor with a worm gear, is provided to drive the linear position of the adjustment mechanism 40. The actuator 404 drives the load cell 64 or other member against the mounting component 68 that is connected to the frame 12.
The actuators 402, 404 are connected to a controller housed in an electronics housing 406. The controller is configured to control the actuators 402, 404 to actuate the adjustment mechanism 40 to change the active positions of the magnet assemblies 42, 44, so as to controllably vary the resistance against rotation of the wheel.
In other embodiments, the actuator 404 is omitted and the linear position of the adjustment mechanism 40 is manually adjusted as with the apparatus 10. The rotational positions of the caliper arms 60, 62 and connected magnet assemblies 42, 44 are adjusted using the actuator 402 as controlled by the controller. In such embodiments, a quick release mechanism 70 (see
In other embodiments, the adjustment mechanism 40, magnet assemblies 42, 44, one or both actuators 402, 404, and the controller are provided with a clamp 202 (see
Shown in
Alternatively,
The cycling resistance apparatus 700 includes one or more magnet assemblies 42, 44 connected to an adjustment mechanism 702. The adjustment mechanism 702 is configured to attach to the frame 710 of the bicycle. The rotating disc 712 of a disc brake of the bicycle acts as the electrically conductive rotational component that magnetically interacts with the one or more magnet assemblies 42, 44, which may be located on one side or on opposite sides of the disc 712. The adjustment mechanism 702 can include one or more lever arms, such as one or more caliper arms, a ball and slot structure, or similar. The adjustment mechanism positions magnets of the magnet assembly 42, 44 at an active position to induce eddy currents in the disc 712 of the disc brake to provide resistance against rotation of the wheel. The adjustment mechanism 702 can be configured for manual control, for electromechanical control by a controller, or both, as discussed elsewhere herein.
The mounting clamp 202 of the cycling resistance apparatus 200 includes a pair of opposing clamp members 220. One clamp member 220 is connected to the adjustment mechanism 206, specifically the member the defines the slot 212, and the other clamp member 220 is used to straddle a portion of the bicycle frame. The clamp member 220 are connected together by bolts through holes, or other type of fastener, so as to sandwich the portion of the frame to which the apparatus is attached to secure the cycling resistance apparatus 200 to the bicycle.
The apparatus 800 includes a stationary frame 802 to which one or more magnet assemblies 804 are attached. Each magnet assembly 804 is connected to the stationary frame 802 via a support arm 806 and a mount 808 that form an adjustment mechanism. In this embodiment, two opposing magnet assemblies 804 are used, one on each side of the bicycle wheel rim 30. The mount 808 is configured to adjust the position of the support arms 806 and magnet assemblies 804 with respect to the rim 30. The adjustment mechanism can be configured for manual control, for electromechanical control by a controller, or both, as discussed elsewhere herein. The apparatus 800, by virtue of the one or more magnet assemblies 804, generates cycling resistance by way of inducing eddy currents in the rim 30, as discussed elsewhere herein.
The apparatus 800 further includes a flywheel assembly 810 rotationally mounted to the stationary frame 802. The flywheel assembly 810 includes a flywheel 812 and a plurality of magnets 814 mounted to the flywheel 812. In this embodiment, the magnets 814 are mounted along a perimeter of the flywheel 812 on a surface of the flywheel 812 that faces the bicycle wheel rim 30. As the flywheel 812 rotates, magnets 814 are brought adjacent the rim 30 to induce eddy currents in the rim 30, so as to increase system inertia. The rotational axis of the flywheel 812 may be parallel to the wheel's rotation axis 820 (as depicted), perpendicular to the rotation axis 820, or at some other angle relative to the rotation axis 820. Magnetic interaction between the flywheel assembly 810 and the bicycle rim 30 stores rotational energy of the wheel, releasing additional energy when the wheel decelerates and absorbing additional energy when the wheel accelerates, thereby acting to regulate wheel speed and mitigate speed variation during pedal strokes. The flywheel assembly 810 can be used with any of the other embodiments discussed herein.
The advantages of the present invention over the prior art are numerous. For one, the rider's own bicycle can be used and the present invention does not require magnets to be installed on the bicycle. Resistance is generated by magnetic interaction that is provided through the rim or other rotational component that is normally present on the bicycle. Moreover, when the invention is used with a stationary frame, tire wear is eliminated by virtue of the magnetic interaction with the rim or other rotational component of the bicycle being the sole source of resistance. No tire-contacting roller is needed. Elimination of tire contact means that noise is greatly reduced over conventional apparatuses. Noise is also reduced as compared to prior art designs that use complex arrangements of specialized rotating and stationary components. In addition, the present invention is readily collapsible to a very compact form for efficient storage (e.g., under a couch).
While the foregoing provides certain non-limiting example embodiments, it should be understood that combinations, subsets, and variations of the foregoing are contemplated. The monopoly sought is defined by the claims.
This application claims priority to U.S. Ser. No. 62/221,928, filed Sep. 22, 2015, which is incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/IB2016/055643 | 9/21/2016 | WO | 00 |
Number | Date | Country | |
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62221928 | Sep 2015 | US |