FR3065940A1 - MOTORIZED ASSISTANCE DEVICE OF PEDAL - Google Patents

Abstract

The present invention relates to a motorized pedal assist device (100) comprising a platen (140) configured to drive a bicycle chain, a motor, and a warp gear (120) configured to increase engine torque and rotating the plate (140).

Description

Holder (s): LIMEMOTION - MOTORS Simplified stock company.

by

O Extension request (s):

® Agent (s): CABINET GERMAIN & MAUREAU.

® MOTORIZED PEDAL ASSISTANCE DEVICE.

@) The present invention relates to a motorized pedal assist device (100) comprising a plate (140) configured to drive a bicycle chain, a motor, and a strain wave gear (120) configured to increase the torque of the motor and rotate the plate (140).

FR 3 065 940 - A1

Field of the invention

The field of the present invention relates to that of electrically assisted bicycles. It relates particularly, but not exclusively, to the field of motorized pedal assist devices comprising a deformation wave gear.

Prior art

Nowadays, various types of devices for electrically assisted bicycles are available on the market, for example motors integrated either in the rear wheel or in the front wheel, or motors integrated in a crank axle with a planetary reduction gear. These are housed in the lower part of the bicycle frame, but unfortunately have a large size and weight. We aim to solve this technical problem.

Statement of the invention

The aim of the present invention is to solve all or part of the drawbacks mentioned above in the form of a motorized pedal assist device comprising:

a deformation wave gear; the strain wave gear comprising at least one strain wave generator, a stationary element and a transmission member; the strain wave gear is configured to increase the torque between the strain wave generator and the transmission member;

a motor; the motor comprising an interior housing delimited by an interior surface and forming a chassis; the chassis comprising a stator, attached to the interior surface and a rotor, movable in rotation relative to the chassis; the motor being configured to drive in rotation the generator of deformation waves in a direction of drive and the transmission member;

a tray; the plate being configured to drive a chain and be mechanically connected to the transmission member; and, a drive shaft; the transmission shaft being configured to be mechanically connected to the plate;

characterized in that the stationary element is fixed radially to the interior surface of the chassis.

Thus, thanks to this arrangement, the size of the deformation wave gear is reduced.

The motorized pedal assist device may also have one or more of the following characteristics, taken alone or in combination.

According to one embodiment, the chassis forms a bottom bracket or a hub.

Thus, thanks to this arrangement, the engine chassis can be inserted into a hub or be the hub of a bottom bracket axle.

According to one embodiment, the stationary element comprises an internal periphery and teeth arranged on the internal periphery of the stationary element.

According to one embodiment, the teeth of the stationary element extend radially towards the inside of the stationary element.

Thus, thanks to this arrangement, the stationary element can cooperate with a part housed inside the stationary element

According to one embodiment, the transmission member comprises an inner periphery and teeth arranged on the inner periphery of the transmission member.

According to one embodiment, the teeth of the transmission member extend radially towards the inside of the transmission member.

Thus, thanks to this arrangement, the transmission member can cooperate with a part housed inside the transmission member

According to one embodiment, the transmission member is adjacent to the stationary element.

According to one embodiment, the deformation wave gear comprises a drive member; the drive member is placed inside the transmission member and / or the stationary element and comprises an outer periphery and teeth arranged on the outer periphery of the drive member; the teeth of the drive member mesh with the teeth of the transmission member.

Thus, thanks to this arrangement, the deformation wave gear allows reduced play, a good transmission ratio, a compact and very light mechanism, good torque transmission, and a rotor and a coaxial transmission shaft.

According to one embodiment, the teeth of the drive member extend radially outward from the drive member.

Thus, thanks to this arrangement, the drive member allows the movement of the transmission member.

According to one embodiment, the generator of deformation waves is inserted inside the drive member.

According to one embodiment:

the rotor is integral in rotation with the strain wave generator and is configured to rotate the strain wave generator in a drive direction, and configured so that when the strain wave generator performs a movement in rotation, the deformation wave generator moves the teeth of the drive member while pressing on the teeth of the stationary element so as to cause the rotation of the transmission member; and, the stator surrounds the rotor and is integral with the chassis.

According to one embodiment, the rotor comprises at least two polar arcs; said at least two polar arcs have a radial dimension of between 7 and 12 mm.

Thus, thanks to this arrangement, the motorized pedal assist device can be inserted into a pedal hub.

According to one embodiment, the stator comprises a number of phases between 3 and 6, and preferably a number of phases equal to 3, 5 or 6.

According to one embodiment, the plate is mounted mobile in rotation and is configured to be mechanically connected to the transmission member by means of a first free wheel so that when the transmission member is driven by the drive member, the plate is rotated.

According to one embodiment, the transmission member comprises a first transmission part and a second transmission part; the first transmission part being configured to be in contact with the drive member and the second transmission part being configured to be in contact with the first freewheel.

According to one embodiment, the first free wheel is included between the second free wheel and the transmission member.

According to one embodiment, the transmission shaft is mechanically connected to the plate via a second free wheel so that when the transmission shaft is rotated, the plate is rotated.

According to one embodiment, the second free wheel is between the first free wheel and the drive shaft.

According to one embodiment, the rotor is mounted mobile in rotation on the transmission shaft.

According to one embodiment, the motorized pedal assist device comprises a device for measuring the speed of rotation; the measuring device comprises a hall effect sensor fixed to the chassis and a pole wheel secured to the drive shaft.

According to one embodiment, the motorized pedal assist device comprises a wedging member; the wedging member is disposed between the stator and the transmission member so as to limit the transverse movement of the transmission member towards the stator.

Other characteristics and advantages of the invention will appear better on reading the following description of an embodiment of the invention given by way of non-limiting example.

List of Figures

The invention will be better understood using the detailed description which is set out below with reference to the drawing, in which:

FIG. 1 shows an example bottom bracket in which the motorized bottom bracket 100 according to the invention is implemented;

Figure 2A shows a front view of a bottom bracket; and, Figure 2B shows a view along section B-B of the bottom bracket of Figure 2A when the motorized bottom bracket 100 according to the invention is implemented.

In the detailed description which follows of the figures defined above, the same elements or the elements fulfilling identical functions may retain the same references so as to simplify the understanding of the invention.

General principle

The present invention is intended to assist the user in his pedaling efforts. Indeed, the user, that is to say the Cyclist, must be able to turn the crankset axle which drives the chainring without being constrained when the assistance is not engaged.

When the pedaling assistance is requested by the applicant, a measuring device fixed on the crankset axle transmits the order to the engine to operate. The motor then starts and indirectly drives the crankset. In other words, the motorized pedal assist device 100 allows, on the one hand, actuation of the pedal by the user without discomfort when the engine is not running, and on the other hand, assistance in the effort when the engine is running.

Description of an embodiment of the invention

The motorized pedal assist device 100, shown in FIG. 1 and allowing reduced play, a good transmission ratio, a compact and very light mechanism, good torque transmission, and a coaxial rotor and shaft. , comprises a motor, a deformation wave gear 120, and a crankset. Thus, thanks to this arrangement, the strain wave gear 120.

The motor is composed of a chassis 101 forming a bottom bracket or a hub so that it can be inserted into a hub or be the hub of a bottom bracket pin, a rotor 131, and a stator 133 integrated. in the chassis 101. This chassis 101 forms an interior housing delimited by its interior surface. This interior housing is intended to receive the stator 133, attached to the interior surface of the chassis 101 and a rotor 131. The latter, that is to say the rotor 131, comprises a set of polar arcs 135 having a radial dimension. between 7 and 12 mm and the number of polar arcs of the set of polar arcs 135 may vary depending on the number of phases, that is to say between 3 and 6, and preferably be equal to 3, 5 or 6. The rotor 131 is movable in rotation relative to the chassis 101. Thus, the motor can rotate the deformation wave gear in a drive direction.

The strain wave gear, mentioned previously, comprises a transmission member 123, a strain wave generator 127 integral with the rotor 131 and a stationary element 121 fixed radially to the interior surface of the chassis 101 so as to make the gear with compact deformation wave and easy assembly. Furthermore, the motorized pedal assist device 100 may also include a wedging member 132 disposed between the stator 133 and the stationary element 121 so as to limit the transverse movement of the transmission member 123 towards the stator 133. In particular, this arrangement makes it possible to spatially isolate the transmission member 123 from the stator 133 by means of the wedging member 132 which is inserted between the transmission member 123 and the stator 133 and thus avoid that the transmission member 123 only cuts the electrical connection of the stator 133.

The stationary element 121, mentioned above, comprises an internal periphery and teeth 122 arranged on this internal periphery, that is to say on the internal periphery of the stationary element 121, more precisely, the teeth 122 of the stationary element 121 extend radially towards the inside of the stationary element 121 so as to be able to cooperate with a part housed inside the stationary element such as for example a generator of deformation waves 127.

Like the stationary element 121, the transmission member 123, cited above and adjacent to the stationary element 121, also includes an inner periphery and teeth arranged on the inner periphery of the transmission member 123 more precisely, the teeth 126 of the transmission member 123 extend radially towards the inside of the transmission member 123 so as to be able to cooperate with a part housed inside the transmission member 123. Furthermore, for reasons of assembly and compactness, the transmission member 123 may comprise a first transmission part 128 and a second transmission part 129: the first transmission part 128 being configured to be in contact with the drive member and the second transmission part 129 being configured to be in indirect contact with the plate.

This part, which can be housed inside the transmission member 123 and / or the stationary element 121 as shown in FIG. 2B in section view according to section BB of FIG. 2A, is a member d drive 125. The drive member 125 is, in fact, placed inside the transmission member 123 and / or the stationary element 121 and includes an outer periphery and teeth 134 arranged on the periphery outside of the drive member 125 so that the teeth 134 of the drive member 125 mesh with the teeth 126 of the transmission member 123.

To do this, the rotor 131, integral in rotation with the deformation wave generator 127 as specified above, rotates the deformation wave generator 127 in a driving direction, and is configured so that when the generator of deformation waves 127 performs a rotational movement, the generator of deformation waves 127 moves the teeth 134 of the drive member 125 while pressing on the teeth 122 of the stationary element 121 so as to cause its turn the rotation of the transmission member 123.

Thus, the strain wave gear 120 increases the torque of the motor between the strain wave generator 127 and the transmission member 123 so that when the strain wave generator 127 is driven by the motor, the 'deformation wave gear increases, by a gear set described above, the engine torque. This torque is then transmitted to the pedal, which comprising a chainring 140 and a transmission shaft 150. The latter, that is to say the transmission shaft 150, comprises a pole wheel which associated with a fixed hall effect sensor chassis 101 forms a measuring device. This measuring device measures the nearby Hall effect and sends, in the form of an analog signal value and / or digital data, the speed of rotation of the transmission shaft 150 to a control unit (not shown). This control unit controls the speed of rotation of the motor as a function of the speed of rotation of the drive shaft 150 so as to allow optimum assistance to the pedaling for the user.

The plate 140 is configured to drive a chain and to be mechanically connected to the transmission member 123 by means of a first free wheel 124.

The transmission shaft 150, on which the rotor 131 is mounted mobile in rotation, is configured to be mechanically connected to the plate 140. The plate 140 is mounted mobile in rotation and is configured to be mechanically connected to the transmission member 123 by means of a first free wheel 124 so that when the transmission member 123 is driven by the drive member 125, only the plate 140 is driven in rotation.

The transmission shaft 150, for its part, is mechanically connected to the plate 140 by means of a second free wheel 145, comprised between the first free wheel 124 and the transmission shaft 150, so that when the 'transmission shaft 150 is rotated, only the plate 140 is rotated.

Claims (16)

1. Motorized pedal assist device (100) comprising: a warp wave gear (120); the strain wave gear (120) comprising at least one strain wave generator (127), a stationary member (121) and a transmission member (123); the strain wave gear (120) is configured to increase the torque between the strain wave generator (127) and the transmission member (123); a motor; the motor comprising an internal housing delimited by an internal surface and forming a frame (101); the chassis (101) comprising a stator (133), attached to the interior surface and a rotor (131), movable in rotation relative to the chassis (101); the motor being configured to rotate the deformation wave generator (127) in a drive direction and the transmission member (123); a tray (140); the plate (140) being configured to drive a chain and be mechanically connected to the transmission member (123); and, a drive shaft (150); the transmission shaft (150) being configured to be mechanically connected to the plate (140); characterized in that the stationary member (121) is fixed radially to the interior surface of the frame (101). 2. motorized pedal assist device (100) according to claim 1, wherein the chassis (101) forms a bottom bracket or a hub. 3. Motorized pedal assist device (100) according to claim 1 or claim 2, wherein the stationary element (121) comprises an inner periphery and teeth (122) arranged on the inner periphery of the stationary element (121). 4. Motorized pedal assist device (100) according to any one of the preceding claims, in which the transmission member (123) comprises an inner periphery and teeth (126) disposed on the inner periphery of the member. transmission (123). 5. motorized pedal assist device (100) according to claim 4, wherein the deformation wave gear (120) comprises a drive member (125); the drive member (125) is placed inside the transmission member (123) and / or the stationary element (121) and comprises an outer periphery and teeth (134) arranged on the periphery outside of the drive member (125); the teeth (134) of the drive member (125) mesh the teeth (126) of the transmission member (123). 6. Motorized pedal assist device (100) according to claim 5, in which the deformation wave generator (127) is inserted inside the drive member (125). 7. Motorized pedal assist device (100) according to claim 5 or claim 6, in which: the rotor (131) is rotationally integral with the deformation wave generator (127) and is configured to rotate the deformation wave generator (127) in a driving direction, and configured so that when the deformation wave generator (127) rotates, the deformation wave generator (127) moves the teeth (134) of the drive member (125) by pressing on the teeth (122) of the stationary element (121) so as to cause the rotation of the transmission member (123); and, the stator (133) surrounds the rotor (131) and is integral with the chassis (101). 8. motorized pedal assist device (100) according to any one of the preceding claims, in which the rotor (131) comprises at least two polar arcs (135); said at least two polar arcs (135) have a radial dimension of between 7 and 12 mm. 9. motorized pedal assist device (100) according to any one of the preceding claims, in which the stator (133) comprises a number of phases between 3 and 6, and preferably a number of phases equal to 3, 5 or 6. 10. Motorized pedal assist device (100) according to any one of the preceding claims, in which the plate (140) is mounted movable in rotation and is configured to be mechanically connected to the transmission member (123) by through a first free wheel (124) so that when the transmission member (123) is driven by the drive member (125), the plate (140) is rotated. 11. motorized pedal assist device (100) according to any one of the preceding claims, in which the transmission shaft (150) is mechanically connected to the plate (140) by means of a second free wheel ( 145) so that when the drive shaft (150) is rotated, the plate (140) is rotated. 12. motorized pedal assist device (100) according to claims 10 and 11, wherein the first free wheel (124) is between the second free wheel (145) and the transmission member (123). 13. motorized pedal assist device (100) according to claim 11 or 12, wherein the second freewheel (145) is between the first freewheel (124) and the drive shaft (150). 14. Motorized pedal assist device (100) according to any one of the preceding claims, in which the rotor (131) is mounted rotatably on the transmission shaft (150). 15. motorized pedal assist device (100) according to any one of the preceding claims, which comprises a device for measuring rotational speed; the measuring device comprises a hall effect sensor fixed to the chassis (101) and a pole wheel secured to the transmission shaft (150). 16. motorized pedal assist device (100) according to any one of the preceding claims, which comprises a wedging member (132); the wedging member (132) is disposed between the stator (133) and the transmission member (123) so as to limit the transverse movement of the transmission member (123) towards the stator (133). 1/2 145