Various types of stationary exercise equipment have been developed. Known stationary exercise bicycles (“bikes”) may include adjustable force-generating mechanisms that provide resistance to a user pedaling the stationary bike. Cycle trainers are another type of stationary exercise equipment. In general, cycle trainers attach to a bicycle intended for outdoor use (“road bike”) and support the rear wheel of the road bike so it remains stationary while providing resistance to a user pedaling the road bike. However, known devices may suffer from various drawbacks.
One aspect of the present disclosure is a cycle trainer for generating a resistance force in a bicycle when the bicycle is connected to the cycle trainer. The cycle trainer includes a support structure having a forward portion and a rear portion. The support structure is configured to engage and support a bicycle in a stationary position in which a rear wheel of the bicycle does not engage a floor surface when the rear wheel rotates about a rear axis of the bicycle. The cycle trainer includes a bracket structure that is pivotably connected to the support structure for rotation about a first axis. The cycle trainer further includes a roller having an outer diameter. The roller is rotatably mounted to the bracket structure for rotation about a second axis that is spaced apart from the first axis. The cycle trainer further includes a resistance mechanism that is configured to provide a resistance force that resists rotation of the roller. The roller is configured to engage a rear tire of a bicycle at a contact point to define a force tangent line extending through the contact point that is tangent to an outer diameter of the rear tire and the outer diameter of the roller. An effective lever arm line is defined that extends linearly through the contact point and the first axis. The force tangent line and the effective lever arm line define an acute angle there-between such that a compressive force is applied to the bracket structure by the roller during use of the cycle trainer.
Another aspect of the present disclosure is a stationary exercise device. The stationary exercise device may comprise a cycle trainer, or it may comprise a stationary exercise bike. The stationary exercise device includes a support structure and one or more input members such as a pair of pedals movably connected to the support structure. A wheel is rotatably mounted to the support structure, and operably connected to the pedals such that movement of the pedals causes the wheel to rotate. An arm is pivotably mounted to the support structure, and a resistance member is mounted on the arm. The resistance member interacts with the wheel when the wheel is rotating to generate a variable resistance force tending to prevent rotation of the wheel. Changes in force is applied to the pedals cause the arm to pivot and change the resistance force. The changes in the resistance force can be utilized to simulate the effects of momentum experienced by a rider pedaling a moving road bike.
These and other features, advantages, and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and appended drawings.
For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in
With reference to
Cycle trainer 1 includes a support structure such as frame 20. The frame 20 includes angled rear frame members 22A and 22B that are connected to angled front frame members 24A and 24B. A cross member 26 extends between and interconnects the angled rear frame members 22, and includes spaced-apart floor-engaging portions such as first caps 28A and 28B that are configured to engage a floor surface 32. Second caps 34A and 34B are positioned on ends 36A and 36B of angled front frame members 24A and 24B to support a forward portion 38 of frame 20 on floor surface 32. Frame 2 may be constructed from steel or other suitable material, and first caps 28A and 28B and second caps 34A and 34B may constructed from rubber or other similar material, preferably having high friction characteristics.
Cycle trainer 1 also includes connectors 40A and 40B that connect the bicycle 3 to the cycle trainer 1 and support the bicycle 3 with the rear tire 12 spaced above the floor surface 32 such that a user can push on the pedals 16 and rotate the rear wheel 8 of bicycle 3 without causing the bicycle 3 to move. A handle 14 is mechanically connected to connector 40B by linkage (not shown). Handle 14 can be rotated to shift connector 40B inwardly to engage the rear skewer 13 to hold bicycle 3 on cycle trainer 1.
With further reference to
Referring again to
Threaded rod 64 includes an upper portion 74 having right hand threads, and a lower portion 76 having left hand threads. Nut 66 includes right hand threads that threadably engage upper portion 74 of threaded rod 64. A threaded plate 70 includes a flat surface 71 (
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To adjust the initial height of roller 48 (
With further reference to
In use, as a rider applies increasing force to pedals 16 of bicycle 3, forces F1-F4 will also increase due to the resistance force of force-generating device 58. Because the normal forces F3 and F4 increase, the roller 48 is driven more forcefully into contact with tire 12, thereby preventing slipping of tire 12 on roller 48. Because roller 48 has a rigid outer surface whereas tire 12 is somewhat resilient, contact point 100 may move along an arc 102 about horizontal axis A as the forces F1-F4 increase and decrease. Alternatively, roller 48 may have a resilient construction, in which case the contact point 100 may shift along, for example, force tangent line 105 if roller 48 and tire 12 have substantially equal resilience.
In use, a user can initially bring the roller 48 into contact with tire 12 by pushing button 86 of nut 66 to thereby shift the position of the arm 42 as discussed above. Adjustment of knob 62 and preload forces 80A and 82A (
Referring again to
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The magnitude of the eddy currents due to eddy magnet 108 vary directly with the distance between eddy magnet 108 and outer surface 120 of flywheel 104. The air gap distance/actuation is controlled by the preload forces 80A and 82A resulting from springs 80 and 82, respectively. As discussed above, the tension (preload force) of the springs 80 and 82 are controlled and adjusted utilizing knob 62. The lower the preload forces 80A and 82A, the greater the simulation of inertial and momentum effects. If the preload forces 80A and 82 are increased, the simulation of inertial and momentum effects is reduced. In general, larger riders require lower preload forces 80A and 82, and smaller riders require larger spring tensions/preload forces 80A and 82A. The combined inertial and momentum effects increase the effective mass of the flywheel 104 to thereby simulate real motion for humans riding a non-stationary bicycle 3 on a road surface, or to thereby simulate real motion for humans performing another activity such as rowing a boat, riding an outdoor elliptical machine, or riding a recumbent bicycle.
Changes (adjustment) of inertial effects to account for riders having different weights can also be achieved by utilizing an adjustment mechanism (not shown) to shift the position of springs 80 and 82 relative to axis A of arm 42. For example, if springs 80 and 82 are shifted (adjusted) to increase the distance of springs 80 and 82 relative to axis A, the effective stiffness of springs 80 and 82 (i.e. the force required to rotate arm 42 about axis A) will decrease such that for a given force applied to pedals 16, the rotation of arm 42 will increase, thereby increasing the inertia modeling (simulating) effects to simulate increased rider mass/weight. Conversely, adjusting the position of springs 80 and 82 to reduce the length of the moment arm of springs 80 and 82 about axis A will increase the effective stiffness of springs 80 and 82, thereby reducing the inertia modeling effects to more accurately simulate decreased rider mass/weight. It will be understood that adjustment of the inertia modeling effects to account for changes in rider mass/weight may also be accomplished utilizing non-linear springs 80 and 82 (i.e. springs that are not governed by a linear equation of the form F=kΔx), cam mechanisms, etc.
The following is an example of a typical rider's energy on a road bike and the energy stored in a flywheel of a typical stationary trainer. The kinetic energy of a road bike is:
E
k=1/2mv2
It will be understood that the rotational kinetic energy of the wheels and other rotating components will provide some additional kinetic energy.
For a typical prior art stationary trainer the kinetic energy is as follows:
In the illustrated example, a 165 lb. rider at 17 mph will have about 2368 joules of energy on a road bike. However, the flywheel of a typical stationary mechanical trainer will only have about 319 joules of energy during use. Accordingly, typical prior art trainers that utilize only a flywheel only have a small amount of stored kinetic energy relative to a rider on a road bike that is moving. Thus, known stationary trainers that utilize flywheels without providing variable force do not store sufficient kinetic energy to accurately simulate the effects of momentum that are experienced on a moving road bike.
With further reference to
Trainer 1A also includes a resistance adjustment knob 128 that is connected to a threaded rod 130 having a first portion 132 with right-handed threads, and a second portion 134 having left hand threads. First and second square nuts 136 and 138 threadably engage first and second threaded portions 132 and 134, respectively, and also slidably engage a backing plate 140 that is fixed to frame 2A. First and second springs 142 and 144, respectively act on a washer member 146 that is positioned between springs 142 and 144. Washer member 146 is not threaded, and is therefore free to slide along threaded rod 130, subject to forces acting on washer 146 due to compression of springs 142 and 144. A lever arm 148 includes a first end 150 that is pivotably connected to frame 2 for rotation about a pivot point 151. Lever arm 148 is pivotably connected to washer member 146 at pivot point 152 by a pin or other suitable connector (not shown). An eddy magnet 154 is mounted to outer end 156 of lever arm 148 adjacent an outer surface 120A of flywheel 104A. Flywheel 104A is rotatably mounted to frame 2 for rotation about the second axis BB. As discussed above, the position or height of arm 42A is fixed at a desired position by rotation of adjustment knob 62A. Thus, in use, the position of arm 42A does not change, and the position of second axis BB also does not change.
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Prior to use of trainer 1A, a user can rotate resistance adjustment knob 128 to thereby change the initial position of lever arm 148 and thereby adjust the position of eddy magnet 154 relative to outer surface 120A of flywheel 104A. For example, the components may be configured such that clockwise rotation of knob 128 causes the eddy magnet 154 to move closer to outer surface 120A of flywheel 104A, which increases the magnitude of eddy currents developed during use of trainer 1A, thereby increasing resistance acting on roller 48A. An adjustment knob 158 can be utilized to rotate the first and second portions 132 and 134 of threaded rod 130 to thereby adjust the preload of springs 142 and 144. Thus, the adjustment knob 158 can be utilized to adjust the momentum effects experienced by a rider. Specifically, greater preload of springs 142 and 144 can be utilized if less motion of lever arm 148 is required, and lower spring tension can be utilized if greater movement of lever arm 148 is required. In general, the momentum effects can be adjusted for a rider's weight as discussed in more detail above. Coupling 160 joins rods 130 and 134 and allows them to turn independently such that knobs 128 and 158 also turn independently.
In the trainer 1A of
The net effect of the inertial and momentum effects is to increase the effective mass of flywheel 104A as required to simulate real motion for a human riding a bicycle 3 on a road surface. The inertia/momentum knob 158 may include a torque measurement device (not shown) similar to a torque wrench, and the masses of riders may be correlated with known torques. Also, the masses (weights) of riders may be written on the knob 158 such that a user can simply rotate the knob 158 to the position corresponding to the rider's weight. The resistance force opposing motion of the user is provided by the eddy magnet 154 (
Resistance devices that provide increased force with increased speed (e.g. friction pads) may be utilized to simulate a portion of the effects of increased rolling resistance, wind resistance, and/or other resistance forces experienced by riders that increase based upon speed, and movable eddy magnet 154 may be utilized to further simulate those effects, as well as simulate inertia/momentum (i.e. force-varying) effects.
With further reference to
Rotation of adjustment knob 188 sets the initial position of eddy magnet 180 relative to outer surface 186 of flywheel 174, and rotation of inertia/momentum knob 196 adjusts the preload tension of springs 198 and 200 in substantially the same manner as discussed above in connection with
Eddy magnet 180 generates a resistance force acting along force tangent 105B tending to resist rotation of flywheel 174. The resistance knob 188 can be utilized to adjust the air gap between magnet 180 and outer surface 186 of flywheel 174 to increase or decrease the initial resistance force generated upon rotation of flywheel 174. Adjustment of inertia/momentum knob 196 adjusts the momentum effects as required to account for the weight of an individual rider. Accordingly, the indoor cycle 162 provides simulation of momentum effects in substantially the same manner as described above in connection with the cycle trainers 1 and 1A.
Exercise devices according to the present disclosure provide variable resistance force that simulates inertia and/or momentum in a manner that does not require sensors, a controller, and/or powered actuators. Because the resistance member (e.g. eddy magnet) is mechanically connected to the one or more input members (e.g. pedals), variable forces acting on the one or more input members generates a variable resistance force due to movement of the resistance member relative to one or more output members (e.g. flywheel). The flywheel or other output member may be integrally formed with the one or more input members.
It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.