Loadable bearing for bicycle stand driven roller

Abstract

A bearing assembly is mounted onto the shaft of a rotating wheel of a bicycle exerciser, wherein the rotating wheel is driven by a person on a bicycle. The bearing assembly is loaded so that the inner and outer portions of the bearing assembly are urged in a manner to create a drag on the bearing assembly that is transmitted to the rolling wheel.

Description

BACKGROUND OF THE INVENTION

The present invention relates to a driven roller for a bicycle stand used as an exerciser wherein the shaft that mounts the roller includes bearings that are mounted on the shaft and which can be externally loaded for increasing the drag on the bearings and thereby changing the effort required to drive the roller by the person riding the bicycle.

Bicycle stands are well known and are used for exercisers in many different environments. The way of loading these exercisers at times becomes difficult and the present loading devices take up a substantial amount of room. Various devices that increase friction loading of some type are utilized, including the loading of the driven roller with greater force against the bicycle wheel that is being driven. Additionally, also, electrical generators have been used. Improvements relating to size considerations and ability to easily adjust the load of these devices would be helpful in addressing these problems.

SUMMARY OF THE INVENTION

The present invention relates to a very compact, highly efficient way of loading a driven roller on a bicycle stand that is used as an exerciser. The roller is mounted onto a shaft, and the shaft carries bearings on at least at one end that can be loaded relative to a stationary part of the stand so that the drag of the bearing is increased to in turn load the shaft selected at varying amounts.

The bearing can be loaded by clamping down an outer race of the bearing, or in the case of tapered roller bearings, load can be applied axially to increase the friction or drag between the rollers and the inner and outer races (the cone and cup) of the bearings.

The bearings in one embodiment are coupled with a heat exchanger comprising a finned housing that dissipates heat. In addition, an adjusting mechanism for adjusting the force on the bearings through a spring is formed with fan blades that circulate air through the heat exchanger. A center chamber of the heat exchanger is open to the bearings where heat will be generated, and flow out is provided from the chamber through the outer shell and across the fins.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic rear view of a typical bicycle stand with a loading roller made according to the present invention;

FIG. 2 is a schematic fragmentary side view of the stand of FIG. 1 having a roller wheel support showing a first form of the invention;

FIG. 3 is a top view of the roller wheel support of FIG. 2;

FIG. 4 is a cross sectional view of the center shaft for the roller wheel of a modified form of the loading of the bearings for the roller wheel of FIG. 2;

FIG. 5 is a top plan view of a further modified form of the present invention;

FIG. 6 is a view taken generally along line 6-6 in FIG. 5, but rotated 180 degrees and with parts removed;

FIG. 7 is a sectional view of a spring adjusting nut;

FIG. 8 is a sectional view taken as on line 8-8 in FIG. 7 showing fan blades formed in the interior of the adjusting nut;

FIG. 9 is a schematic sectional view of an alternative embodiment of the present invention;

FIG. 10 is an elevational view of a loading roller adjustable based on a control signal;

FIG. 11 is sectional view of the embodiment of FIG. 10;

FIG. 12 is an elevational view of a worm wheel;

FIG. 13 is a sectional view of the worm wheel taken along lines 13-13 in FIG. 12;

FIG. 14 is top plan view of a drive element;

FIG. 15 is a sectional view of the drive element taken along lines 15-15 in FIG. 14;

FIG. 16 is top plan view of a carrier ring; and

FIG. 17 is a sectional view of the drive element taken along lines 17-17 in FIG. 16.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a stand 10, that has upright support members 12 and a base support 14. Reference is made to U.S. Pat. No. 6,551,220 showing such stand. A bicycle 16 is shown in position being held on supports 18 and 20, on opposite sides in a conventional manner. The mounting of the bicycle can be any desired form. A bicycle wheel loading assembly indicated generally at 22 is mounted onto the base 14 in a suitable manner.

With reference to FIGS. 2 and 3, suitable side supports 24 are coupleable to loading assembly 22 in order to support the loading assembly 22. The side supports 24 can have an overhanging ledge 26 carrying an adjustment screw 28 that is designed to change the angular position of a framework or yoke 30 that is pivotally mounted on a pivot pin 32 to the supports 24 in a suitable manner. The screw 28 can mount into a housing 34, which is shown schematically in FIG. 3.

A rider driven bicycle wheel 36 is shown schematically in FIG. 2, which rides against a roller wheel 38 that is mounted on a shaft 40. The shaft 40 is rotatably mounted in suitable bearings 41 on spaced apart arms 42 of the yoke 30. The shaft 40 extends outwardly along both sides of the yoke 30. A flywheel 44 is mounted on one outwardly extending end of the shaft 40 on the outside of the yoke 30.

The outer end of the shaft opposite from the fly wheel has a ball bearing 50 mounted thereon, and the ball bearing 50 has an inner race 52 on the shaft that rotates with the shaft. The inner race 52 is supported and positioned axially on the shaft in a desired manner. The bearing 50 has an outer race 54 and there are balls 55 between the inner and outer races.

A bearing compression plate 56 has an opening in the center to receive the outer race and is split with a slit 58. The compression plate 56 extends laterally and the slit 58 is along an arm or lever portion 57. The outer ends of the bearing compression plate have a compression adjustment screw 60 that spans the slit 58, and when tightened down, the screw 60 will clamp the compression plate onto the outer race of the bearing. The arm 57 of the bearing compression plate 56 is supported with a cap screw 61 on a frame block 62 that in turn is fixed back to the yoke 30 in a suitable manner with an arm 64 that can be secured to the yoke 30.

There also are preload screws 63 threaded into the bearing compression plate 56 to bear on the outer race 54 and provide a preload to keep the race 54 and plate 56 oriented and also load the bearings if desired. The bearing compression plate 56 cannot rotate, and as the shaft 40 is rotated by driving the bicycle wheel 36, and the roller wheel 38, the load on the bearing 50 between the inner and outer races can be changed by squeezing down the outer race 54 on the balls relative to the inner race. This also can be done with screws 63. Since the inner race rotates with the shaft 40, the shaft 40 is loaded with a friction load from the bearings 50. This load means that the roller wheel 38 is subject to greater drag resisting rotations, and this drag then loads the bicycle wheel 36 in a desired manner. Suitable blocks 66 are provided for positioning the bearing 50 and compression plate 56 to keep the bearing 50 in its desired location axially along the shaft 40. Separate bearings illustrated only schematically at 41 are used for supporting the shaft 40 on the yoke arms 42.

In FIG. 4, a modified shaft for use with a roller wheel that replaces roller wheel 38 is shown. A roller wheel 70 is shown in cross section. This roller wheel replaces the roller wheel 38, and the yoke arms 42 are illustrated. The roller wheel 70 and supports are illustrated schematically, and in this instance tapered roller bearings 72 are positioned at opposite ends of the roller wheel 70 to support the roller wheel on a center shaft 74. The outer races or cups 75 of the tapered roller bearings are press-fitted into or otherwise axially secured by shoulders 75A as shown in the interior of the roller wheel 70. The inner races or cones of the tapered roller bearings are mounted on the shaft 74 so that cones 77 and 78 rotate with the shaft 74.

The shaft 74 has a head 74A on one end that bears against the cone 77 on that side of the roller wheel and a nut 76 on the other end that bears on the cone 78 for the bearing on the opposite side of the roller wheel 70. The cones 77 and 78 of the taper roller bearings can be urged together, which loads the rollers against the cups 75 which are held from moving together by the shoulders 75A in the roller wheel 70, to load the bearings under compression. The drag will cause the rotation of the roller wheel 70 to require more force, which can vary depending on the tightness of the nut 76. The cones 77 and 78 thus are squeezed axially for loading the roller wheel.

In FIGS. 5, 6, 7 and 8, a modified form of the invention is illustrated. The yoke shown at 90 is mounted in the same manner as that previously explained on the stand, and the yoke can be adjusted to change the elevation of the outer end about the axis of pivot pin 32.

In this form of the invention, the yoke has a roller wheel 92 mounted in a recess 94. The roller wheel 92 in this form of the invention has a larger diameter center section against which the driven bicycle wheel will run. This larger diameter roller wheel 92 slows down the speed of rotation of the shaft 96 that mounts the roller wheel, relative to the speed of the bicycle wheel. The shaft 96 mounts the roller wheel 92 in a conventional manner on roller bearings 98, which are mounted on the opposite spaced arms 100 of the yoke 90.

A flywheel 102 is mounted on one outer end of the shaft 96 and it can be seen that a nut 104 is threaded on that end of the shaft 96. A spacer 106 rests against the inner race of the roller bearing 98, to keep the flywheel spaced at a desired location. The shaft 96 extends through the roller wheel 92, and is drivably connected to the roller wheel in a suitable manner. The bearing 98 on the opposite end of the yoke 90 from the flywheel 102 is used for supporting the drag creating bearing arrangement indicated generally at 110.

The shaft 96 has a spacer 112 on that side of the yoke 90 that engages the inner race of the bearing 98 on that side. A spacer hub 114 is mounted over the shaft 96 and supports a tapered roller bearing assembly 116 on its outer surface. A snap ring 124 is used to locate the hub 114 axially and the nut 104 can be tightened to hold the bearing 98 in place on the yoke arm 100 and shaft 96. The taper rolling bearing assembly 116 is held in a control arm 118 around the cup or outer race 126 of the bearing and this control arm 118 is secured from rotation with a pin 120 that fits into a provided receptacle 122 on the yoke 90. The pin 120 can be threaded in place or otherwise held in place as desired.

The snap ring 124 extends into a groove in the shaft 96 and holds the hub 114 from axial movement. The spacers, bearings, and yoke, are such that the nut 104 can be tightened to tighten the entire assembly of the bearings 98, spacers, and the tapered roller bearing assembly 116 in place.

Again, the tapered roller bearing 116 has outer cup 126 held by arm 118, and a cone or inner race 128 that rotates with shaft 96, and rollers 130 between the cup and the cone on that bearing.

In order to provide a drag on the shaft 96, a second tapered roller bearing assembly 134 is supported in place surrounding the shaft 96 on a hub 136 that supports the cone or inner race 138 of bearing 134. The cup 140 of the bearing 134 is supported in a housing 142 that acts as a heat exchanger. Rollers 144 are positioned between the cone 138 and the cup 140. A ring spacer 152 is positioned between the cup 140 of bearing 134 and cup 126 of bearing 116. The cones of the two bearings 116 and 134 taper in opposite directions from the center place between the bearings.

The housing 142 has an open center chamber 143, as can be seen. The shaft 96 extends through the chamber 143 and a spring 146 is positioned over the shaft 96 in the chamber. The spring 146 bears against a hub 136 that has a flange 136A that bears against cone 138.

An adjustment nut 148 is threaded onto a threaded portion 150 of the shaft 96. Adjustment nut 148 has a center wall portion at one end that bears against the spring 146 and creates an axial force on the hub 136, and thus on the cone or inner race 138 of the bearing assembly 134. In turn this increases the load on with the rollers 144 against the cup 140. Spring 146 advantageously provides a constant load to the bearings even when thermal expansion of components occurs due to heating of the components.

The axial force is transmitted from cup 140 by the washer-like ring spacer 152, to the cup or outer race 126 of bearing 116. The load from cup 126 is transmitted by roller 130 to create a drag on the cone 128 or inner race of the bearing 116. The cone 128 is rotating with shaft 96 but the cup 126 is held from rotating by arm 118. This load on the bearings 116 and 134 will cause a need for greater force to rotate the roller wheel 94, which in turn is generated by the person doing the exercise.

The preloading of bearings on the shaft that carries the roller wheel 92 provides an efficient, easy way of loading the exercise device to a desired level.

The heat generated by the friction loads of the two bearings 134 and 116 is dissipated by the housing 142, which has heat-radiating fins 154 thereon. The radiating fins are used for carrying heat to the atmosphere. It can be seen that the arm 118 holds the outer race or cup 126 of the bearing assembly 116, and because of the frictional force carried by the spacer 152, the outer race or cup 140 does not rotate either, so that the heat exchange housing remains stationary. However, nut 148, which is hand adjustable, will rotate with the shaft 96.

Nut 148 is shown in FIGS. 7 and 8, and it is provided with a number of generally radial fins or blades 156 that act like a centrifugal fan so that as the nut rotates while the shaft 96 is rotating, air will be pumped out from the center of chamber 143 through the space between the blades 156 and out through discharge openings 158 in the housing 142. Additionally, the nut 148 has openings 160 on the end wall that are used for intake of air for circulation.

In FIG. 7, the nut 148 has a knurled outer surface 162 for ease of adjustment. The spring 146 (FIG. 5) is selected in size as desired to create the necessary axial force on the two bearings 134 and 116, to in turn create enough drag on the shaft 96 for adequate exercise and to provide for even pressure on the bearings.

It will further be appreciated that different arrangements for loading one or more bearing assemblies can be provided in accordance with the present invention. FIG. 9 is a schematic view of an actuator 200, a shaft 201, outer races 202, 204, inner races 206, 208 and bearings 210, 212. Bearing 210 is provided between outer race 202 and inner race 206 while bearing 212 is provided between outer race 204 and inner race 208. Actuator 200 operates to provide friction force between outer races 202, 204 and inner races 206, 208, respectively. Actuator 200 can be any form of actuator including a hydraulic actuator, pneumatic actuator, electro-mechanical actuator (e.g. motor, gears, levers), etc. In one embodiment, actuator 200 operates to actuate inner races 206, 208 toward outer races 202, 204, respectively. Alternatively, as discussed above in previous embodiments, actuator 200 can force outer races 202, 204 toward inner races 206, 208 respectively. It will further be appreciated that an electrical signal can be provided to actuator 80 and the degree of friction force applied between outer races 202, 204 and inner races 206, 208 can be proportional to the electrical signal.

By way of example and not limitation, FIGS. 9 and 10 illustrate an exemplary embodiment having an actuator 200 comprising a motor 250 receiving an electrical signal that functions as a control signal to adjust the loading of bearings that in turn adjusts the resistance present upon a bicycle wheel. In FIGS. 9 and 10 the same reference numerals have been used as in FIG. 5 to identify similar functioning elements.

As illustrated, motor 250 is coupled to suitable gears disposed in gearbox 252 so as to obtain a desired rotational speed of output shaft 254. Output shaft 254 is coupled to an elongated worm gear 256 rotatably supported in a suitable housing 258. Worm gear 256 meshes with a worm wheel 260 (see also FIGS. 12 and 13) that is disposed for at least partial rotation about shaft 96.

In this embodiment, drive elements (herein rings) 270 and 272 engage cups 126 and 140, respectively, to induce loading on the respective bearings. In particular, rotation of worm wheel 260 causes drive elements 270 and 272 to be selectively displaced toward or away from each other, wherein displacement away from each other causes increased loading upon the bearings.

In one embodiment, stops are provided to limit rotation of worm wheel 260. Referring to FIG. 12, such stops can be embodied as balls 261 that are disposed in recesses 263 formed in worm wheel 260. The balls 261 contact worm gear 256 to limit rotation of worm wheel 260. As appreciated by those skilled in the art, many different mechanisms can be used to limit rotation of worm wheel 260.

In the embodiment illustrated, a plurality of balls 274 are disposed between drive elements 270 and 272 in guide grooves 276 and/or 278 formed respectively therein. With reference also to FIGS. 14 and 15, at least one of the grooves, herein groove 276, varies in depth such that at different positions of the ball 274 in the groove 276 the spacing or distance between drive elements 270 and 272 is also varied. Carrier ring 280 (see also FIGS. 16 and 17) disposed about the shaft 96 has apertures slightly larger than the balls 274 to control the position of each ball in the corresponding groove 276. Carrier ring 280 is coupled to and driven by worm wheel 260. Drive pins 284 couple worm wheel 260 to drive element 272 (e.g. pins engage recesses 285 in drive element 272 as illustrated in FIG. 14), while an o-ring 286 is friction coupled to carrier ring 280. In one illustrative embodiment, three balls 274 are disposed around shaft 96 at substantially equal angular intervals, while the change in depth of groove 276 upon which each respective ball travels is 0.060 inches.

It should be noted nut 148 as illustrated in FIGS. 9 and 10 is also provided with a number of generally radial fins or blades 156 that act like a centrifugal fan so that as the nut rotates while the shaft 96 is rotating, air will be pumped through the housing 142 and preferably out discharge openings 158 in the housing 142. However, in this embodiment the nut 148 has larger extending radial fans that extend adjacent an opening to the housing 142 and where openings are not needed in nut 148.

Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.

Claims

1. A friction loading device for a roller against which a bicycle wheel is engaged for exercise, said friction loading device comprising: a shaft mounting said roller wheel; at least one bearing assembly on the shaft, the bearing having a rotating portion and a stationary portion supported relative to each other; and a loading member for changing the surface positions of the stationary portion to create a friction load on the rotating portion, said rotating portion being mounted to rotate with the roller wheel.

2. The device of claim 1, wherein said bearing comprises rolling elements between the stationary portion and the rotating portion, said rotating portion being urged against the rolling elements to create the load on the rotating portion of the bearing.

3. The device of claim 2, wherein said bearing is a roller bearing, the rotating portion comprises an inner race and the stationary portion comprises an outer race that is distorted in shape for creating a load on the inner race.

4. The device of claim 3, wherein said bearing comprises: a tapered roller bearing, the inner race being a rotating cone, and the outer race being a stationary cup; a plurality of rollers between the cup and the cone, the loading member providing an axial load on the stationary portion urging the rollers against the cone to create a drag on the cone and the shaft on which the cone is mounted.

5. The device of claim 1 and further comprising a housing surrounding the shaft, the housing including fins to dissipate heat generated from the friction load.

6. The device of claim 1 wherein the loading member comprises an adjustable nut.

7. The device of claim 6 wherein the nut includes radial fins that are rotatable with the shaft to force air into the housing and across the fins.

8. The device of claim 7 wherein the housing includes openings proximate the fins to allow air flow therethrough.

9. The device of claim 1 wherein the loading member comprises a bearing compression plate having a slit such that when opposed sides of the slit are forced together, the load is created.

10. The device of claim 1, wherein said bearing comprises rolling elements between the stationary portion and the rotating portion, said stationary portion being urged against the rolling elements to create the load on the rotating portion of the bearing.

11. The device of claim 1 wherein the loading member comprises an actuator that is operated to provide the load in proportion to an electrical signal.

12. An exerciser, comprising: a stand adapted to engage a bicycle; the device of claim 1 coupled to the stand and adapted to engage a wheel of the bicycle.