FR2698279A1 - Exercise bicycle with elastic belt round wheel - has roller passing around belt and joined to metallic disc in which Foucault currents are induced by magnets inside stirrup covering disc - Google Patents

Abstract

The exercise appts. (1) has a wheel (6) with an elastic belt (22) round its periphery. A roller (31), mounted freely on a shaft (30), contacts and causes rotation of the belt and a metallic disc (33) is joined to it. A stirrup (29), with magnets (39) on the inside of its branches, covers the disc and induces Foucault currents in this. The stirrup pivots on an axle (28), parallel to the axle of the disc and the roller. The wheel has two side plates (15) with peripheral edges which engage in peripheral grooves in the belt. An inertia wheel (32) is joined to the roller. USE/ADVANTAGE - Exercise bicycle with effort modulated by magnetic current, and imposed on user gradually.

Description

DEVICE FOR MODULATING AN EFFORT AND APPARATUS FOR
SHAPING COMPRISING SUCH A DEVICE
The subject of the present invention is a device for modulating an effort intended to equip a fitness, training or rehabilitation device in the gym or in an apartment, of the exercise bike, rower, treadmill or mounting device type. stairs or other, to modulate an effort to provide when using said device.

 In order to allow the user of an apparatus of the above type, which will be designated below by shaping apparatus to facilitate the presentation, to adjust the value of the effort which he must provide , for example to drive the wheel of an exercise bike or to pull on the oars of a rower, various devices for modulating this effort have already been proposed.

 This is particularly the case of the device for modulating a force in which the modulation of the force is obtained by variably creating currents induced in a rotating metallic mass; more specifically, a stirrup comprises two branches inside which magnets are placed, said stirrup being caused to more or less overlap the rotating mass by pivoting about an axis parallel to that of the rotating mass; so far, the rotating mass is a thick metallic wheel, also constituting a flywheel, which the user of the shaping device must rotate. Such a device has a number of drawbacks.

 Such a large diameter wheel is heavy and requires precise machining to avoid any imbalance; in addition, for low rotational speeds, eddy current braking is practically non-existent, within a non-negligible range and, therefore, a great reduction is necessary at the level of the user, all this making the cost price high. of the device; moreover, the wheel being necessarily thick, the air gap in front of the magnet caliper is difficult to control. Although eddy current braking does apply to a device for modulating a force, the fact that braking the wheel is a regular, progressive function, with no steep speed and, therefore, its use is soft and pleasant, unfortunately, the above drawbacks have limited its development.

 Among other devices for modulating a force for shaping apparatus, there is also known the device consisting of a wheel equipped at its periphery with an elastic bandage on which is applied a roller mounted idly on a tree, the force applying the roller to the tire being adjusted so as to modulate the effort to be provided by the user to rotate the wheel; such a device for modulating a force is very effective, of simple construction, without wearing part and gives complete satisfaction; however, its high efficiency is reflected, in particular at the strong braking torques of the wheel and at the high rotational speeds of the latter, by cyclic irregularities in one unpleasant effort for the user.

 The subject of the present invention is a device for modulating a force intended to equip a shaping apparatus for modulating the effort to be supplied when using the shaping apparatus which is effective whatever this effort, this effort being felt by the user as progressive and smooth, while being simple in design and of low cost.

 The invention takes advantage of the performance of a wheeled and roller device, and that of an eddy current device.

Thus, according to the invention, a device for modulating a force intended to equip a shaping device for modulating the effort to be supplied when using said device comprises a wheel comprising at its periphery an elastic bandage on which is applied a roller mounted idly on a shaft, said roller being integral with a metal disc in which are induced currents
Foucault.

 Advantageously, the force of application of the roller on the tire is adjustable.

 The wheel consists of two lateral flanges having the general shape of a circular disc carrying at their periphery the tire; each flange has a peripheral edge shaped as a substantially axial collar engaging in a peripheral and lateral groove of the bandage, the assembly of the flanges on the bandage being carried out by any suitable means, for example by screwing advantageously, the flanges are made of plastic ; the bandage is annular, molded in one piece from a synthetic material such as an elastomeric plastic.

 For the induction of eddy currents in the metal disc secured to the roller, a stirrup comprises two branches inside which magnets are placed, said stirrup overlapping the metal disc secured to the roller; said stirrup is pivotally mounted around an axis parallel to that of the metal disc and of the roller advantageously, its position, around its axis, is adjustable, so that according to this adjustment the stirrup more or less overlaps the disc metallic, thanks to which the eddy current braking of the metallic disc is adjustable.

 According to one embodiment, the axis of the roller is fixed while the axis of the wheel is mounted mobile, the effort of the user to rotate the wheel applying the tire of the wheel against the roller; the axis of the wheel is carried by a fork-shaped arm articulated around an axis carried advantageously by a support, a spring urges, at rest, the wheel away from the roller; as a variant, there is no spring urging the wheel away from the roller but, a flexible transmission means, of the chain or belt type, in particular toothed, being provided for the drive in rotation of the wheel by the user , a tensioner cooperating with said transmission means is provided, said tensioner comprising an elastic means disposed in a direction such that it tightens said transmission means.

 According to this embodiment in which the axis of the wheel is mounted mobile, the effort of applying the roller to the tire is adjusted by the effort of the user to drive the wheel in rotation, by means of the flexible means of transmission; this arrangement has the advantage that when the effort of the user is caused to vary when passing through dead centers, as is the case in particular when the effort is applied, via the flexible transmission means, by a crankset which, as we know, when the device is a bicycle, has two dead points: a top dead center and a bottom point, these passages in neutral are facilitated and they disappear in the drive movement of the wheel by the user; the user comfort of the device is thereby increased.

 According to another embodiment, the axis of the wheel is fixed while the axis of the roller is movable; the axis of the roller is carried by a lever articulated on a support carried by the shaping apparatus equipped with the device for modulating the force.

 Whatever the embodiment, the invention also provides for limiting the stroke of the movable member, roller or wheel, which also limits the stroke of "penetration" of the roller in the elastic bandage, therefore the maximum value of the resistance to wheel drive; by making this stroke limitation adjustable by the user, the number of combinations of the two resistances is multiplied, that due to the eddy currents and that due to the roller and the tire.

 Of course, provision can also be made, in order to increase the power of the device, to associate with the roller a flywheel which has, in addition, the advantage of also participating in the regulation of the force as a function of the speed of rotation.

 The invention also relates to an apparatus for shaping, training or rehabilitation, in the room or in an apartment, equipped with the device for modulating an effort according to the present invention.

 To better understand the object of the invention, we will now describe, by way of purely illustrative and nonlimiting example, an embodiment shown in the accompanying drawing.

On this drawing:
- Figure 1 shows, in elevation, a device for modulating a force according to the invention mounted, for example, on an exercise bike shown partially;
- Figure 2 is a partial section along the line II-II of Figure 1;
- Figure 3 is similar to Figure 1 and shows a variant of the device for modulating a force;
- Figure 4 is a partial view of a variant of the device according to Figure 1.

 In FIG. 1, an exercise bike 1 has a frame 2 carrying a saddle 3; the frame 2 is integral with a support 4 intended to rest on the ground by means of pads 5.

 A wheel 6 is carried, by means of an axle 7 passing through its hub mounted in rotation on said axle 7, by an arm 8 in the form of a fork articulated around an axle 41 carried by a bracket 40 secured to the support 4 ; the wheel 6 is driven by means of a flexible transmission means, here a chain 14; a toothed pinion 9 is integral in rotation with the hub of the wheel 6; a bottom bracket 10, having two pedals 11 and a chainring 12, is carried by a bottom bracket 13 secured to the frame 2; the toothed pinion 9 and the plate 12 are engaged with the chain 14; such an arrangement is perfectly known and will therefore not be more detailed.

 The wheel 6 is a wheel with roller braking; such a wheel comprises, in the example shown, two plastic flanges 15 and 16; each of the flanges 15 and 16 has a peripheral edge, respectively 20 and 21, shaped as a collar extending substantially along the axis of the wheel 6.

 An annular bandage 22, molded in a single piece of elastomer, is provided at the periphery of the wheel 6; laterally, the tire 22 has peripheral grooves 23, 24 in which the collars 20 and 21 of the flanges 15 and 16 engage; thus, when the flanges are assembled by connecting means, such as screws 25 and nuts 26, the bandage 22 is held at the periphery of the wheel 6, as can be seen in FIG. 2.

 The support 4 carries a bracket 27 to which is fixed an axis 28 on which is hinged a stirrup 29; the stirrup 29 is coupled to a control cable 44 making it possible to exert on the stirrup 29 a torque around the axis 28; another bracket 38 carried by the support 4 carries a shaft 30 on which a roller 31 journals, idly mounted on the shaft 30; the position of the bracket 38 and the roller 30, with respect to the wheel 6, is such that, when an action is exerted on the pedals 1 1 to rotate the wheel 6, the tension of the chain 14 requests, to the left of Figure 1, the axis 7 of the wheel 6, by rotation of the fork 8 around the axis 41 and the roller 31 cooperates with the cylindrical peripheral external face of the tire 22 ;; as is known, the greater the force applied to the roller 31 by the tire 22 and the greater the resistance opposed by the wheel to the implementation of the pedal 10 by the user.

 A thin metal disc 33, of the same axis as the roller 31, is integral with the roller 31; the stirrup 29 is internally lined with ferrites 39 and the mounting of the stirrup 29 is such that it straddles the disc 33; a control cable 44 makes it possible to position the stirrup 29 around its axis 28: it can be seen that in the position of the stirrup 29 shown in dashed lines in FIG. 1 all the ferrites 39 are not entirely opposite the disc 33 and that, in this position for example, the braking torque due to the eddy currents induced in the disc 33 when it rotates is less than the torque corresponding to the position in solid line of the caliper 29.

 Advantageously, to avoid the marking of the tire by the roller when the device is not in use, a spring-loaded cylinder 42 is placed between the fork 8 and the support 4 so as to stress the fork 8, therefore the wheel 6, to the right of FIG. 1, the length of the chain 14 allowing, in this rest position, a slight clearance between the roller 31 and the tire 22.

 A flywheel 32 is integral in rotation with the roller 31.

 Referring to Figure 4, on which the elements identical to those of Figure 1 have the same references, the fork 8 is no longer biased by a spring 43 so that the wheel 6 is no longer at rest away from the roller 31; according to this variant, a support 56 integral with the fork 8 carries at its free end, on the one hand, an arm 60 on which is mounted a tensioner 55 for a chain 54, and, on the other hand, a bracket 61 including one a thread 58 is passed through the thread; the end 59 of the screw 58 constitutes a stop cooperating with a counter-stop 57 secured to the frame 2; the clearance, adjustable by the screw 58, existing between the stop 59 and the counter-stop 57 limits the movement to the left of FIG. 4 of the fork 8, therefore the crushing of the tire of the wheel 6 by the roller.

 Figure 3 shows a variant device for modulating a force according to the invention fitted to the exercise bike of Figure 1; in this FIG. 3, the same elements as those relating to FIG. 1 have the same references as in FIG. 1 and will therefore not be described. Compared to Figure 1, the apparatus 1 here comprises a wheel 6 whose axis 7 is fixed; the axis 7 is carried by a fixed fork 108, horizontal, integral with the frame 2. The axis 30 of the roller 31 is carried by a lever 129 at one of its ends; the lever 129 is articulated around an axis 128 carried by a bracket 127 secured to the support 4; at the other end of the lever 129 is coupled an operating rod 144; a force to the left of FIG. 3 applied to the rod 144 applies the roller 31 to the tire 22 of the wheel 6; the braking torque applied to the wheel by the roller is therefore adjustable by modulating the force applied to the rod 144.

 According to this variant of FIG. 3, the user has two force modulation means: the rod 144 and the cable 44 for positioning the stirrup 29 relative to the metal disc 33. It is thus possible for him to have a device with an extended power range; for example, the operation of the rod 144 corresponds to a power which can go up to 200 watts and a little more, the cable 44 holding the bracket 29 in the minimum overlapping position of the disc 33; a power much greater than 200 watts is obtained by then moving the stirrup 29 towards its position of maximum overlap of the disc 33.

 The device which has just been described advantageously combines the performances of a device with a wheel with a tire and roller, and those of a device with braking by eddy currents; thus, whatever the speed of the wheel and the braking torque, defined by the user, which is applied to it, the operation of the device is pleasant, without jerks; in addition, this is obtained using a simple, robust and wear-free construction device, and therefore of a low cost price.

Claims (12)

 1 - Device for modulating a force intended to equip an apparatus (1) for shaping the modulation of the force to be supplied when using said apparatus (1), comprising a wheel (6) comprising at its periphery a elastic bandage (22) on which is applied a roller (31) mounted idly on a shaft (30), characterized in that said roller (31) is integral with a metal disc (33) in which are induced currents of Foucault.  2-Device according to claim 1, characterized in that the force of application of the roller (31) on the tire (22) is adjustable.  3 - Device according to one of claims 1 or 2, characterized in that the wheel consists of two side flanges (15, 16) carrying at their periphery the bandage (22), each flange (15, 16) having a peripheral edge (20, 21) engaging in a peripheral groove (23, 24) of the bandage (22).  4-Device according to one of claims 1 to 3, characterized in that a flywheel (32) is integral in rotation with the roller (31).  5 - Device according to claim 1, characterized in that for the induction of eddy currents in the disc (33), a bracket (29) comprises two branches inside which are placed magnets (39), said stirrup (29) straddling the disc (33).  6 - Device according to claim 5, characterized in that the stirrup (29) is pivotally mounted about an axis (28) parallel to the axis (30) common to the disc (33) and the roller (31) , a cable (44) allowing the positioning of the stirrup (29) around its axis (28).  7 - Device according to one of claims 1 to 6, characterized in that the axis (30) of the roller (31) is fixed while the axis (7) of the wheel (6) is movable, the axle (7) of the wheel (6) being carried by an arm (8) in the form of a fork articulated around an axle (41) carried by a support (4).  8 - Device according to claim 7, characterized in that a spring (43) is disposed between the arm (8) in the form of a fork and the support (4), and urges the wheel (6) away from the roller ( 31).  9 - Device according to claim 7, wherein a flexible transmission means (54) is provided for driving the wheel in rotation by the user, characterized in that a tensioner (55) cooperates with said means transmission (54).  10 - Device according to one of claims 1 to 6, characterized in that the axis (7) of the wheel (6) is fixed, while the axis (30) of the roller (31) is movable, l 'axis (30) of the roller (31) being carried by a lever (129) articulated around an axis (128) carried by a support (4).  11 - Device according to one of claims t to 10, characterized in that the penetration stroke of the roller (31) in the tire (22) is limited by stop means (58, 59) adjustable.  12 - apparatus for shaping effort to provide modulated, characterized in that it is equipped with a device for modulating a force according to at least one of claims 1 to 1 1 previous.