Self-propelled rolling vehicle

Abstract

Self-propelled rolling machine comprising a chassis, wheels and for each wheel called drive wheel a geared motor unit (4) comprising an electric motor (5) equipped with a drive shaft (6), an output shaft (7) in contact with the drive wheel and a reducer (8) for transmitting the movement from the drive shaft (6) to the output shaft (7), the reducer (8) being housed inside a housing (9) made of synthetic material from which at least a part of the output shaft (7) protrudes and the motor (5) comprising a rotor (10), a stator (11) and a frame (12) surrounding the rotor (10) and the stator (11). The reducer (8) comprises two reduction stages, each comprising a gear (13; 14) composed of two rotating toothed meshing elements (131, 132; 141, 142) each having an external toothing (1311, 1321; 1411, 1421) and in meshing by said external toothing.The drive shaft (6) and the output shaft (7) are parallel shafts with longitudinal axes coinciding or separated from each other by a distance of at most 10 millimeters, and the frame (12) of the motor (5) is formed by a portion of the housing (9). Figure for the abbreviation: Fig. 3.

Description

Title of the invention: Automatically moving rolling machine

[0001] The present invention relates to a rolling machine with automatic movement without a driver sitting or walking behind the machine, also called a robot.

[0002] It relates in particular to a rolling machine with automatic movement without a driver sitting or walking behind the machine, such as a mowing robot, said machine comprising a chassis, wheels carrying the chassis and for each so-called driving wheel a geared motor group for driving the wheel in rotation, the geared motor group for driving a driving wheel in rotation comprising an electric motor equipped with a drive shaft, an output shaft engaged with the driving wheel and a reducer for transmitting the movement of the drive shaft to the output shaft, the reducer being housed inside a casing made of synthetic material from which at least part of the output shaft projects and the motor comprising a rotor, a stator and a casing surrounding the rotor and the stator.

[0003] Such a rolling machine in the form of a mowing robot is known as illustrated by patent FR 3 112 833. Such machines may be intended to remain permanently outdoors and to operate even in the presence of people. It is therefore important that the geared motor unit allows for a smooth transfer of power to limit noise pollution without harming the compactness and simplicity of said machine as well as its robustness.

[0004] To this end, the invention relates to a rolling machine with automatic movement without a driver sitting or walking behind the machine, also called a robot, said machine comprising a chassis, wheels carrying the chassis and for each so-called driving wheel a geared motor group for driving the wheel in rotation, the geared motor group for driving a driving wheel in rotation comprising an electric motor equipped with a motor shaft, an output shaft engaged with the driving wheel and a reducer for transmitting the movement of the motor shaft to the output shaft, the reducer being housed inside a housing made of synthetic material from which at least part of the output shaft projects and the motor comprising a rotor, a stator and a casing surrounding the rotor and the stator, characterized in that the reducer comprises at least two reduction stages,in that each reduction stage comprises a gear composed of at least two toothed rotating meshing elements each having an external toothing and meshing with said external toothing, in that the motor shaft and the output shaft are parallel shafts, in that the longitudinal axes of the motor shaft and the output shaft are coincident or spaced apart from each other by a distance of at most 10 millimeters and in that the motor casing is formed by a part of the housing made of synthetic material housing, the reducer.

[0005] According to one embodiment of the invention, the external toothing of each meshing element of the reducer is a helical toothing.

[0006] According to one embodiment of the invention, each meshing element of the reducer is formed by a toothed wheel or a pinion.

[0007] According to one embodiment of the invention, one of the meshing elements of the first reduction stage and one of the meshing elements of the second reduction stage are made from a single piece and the teeth of said meshing elements made from a single piece are helical teeth of opposite direction.

[0008] According to one embodiment of the invention, the housing is formed of two shells assembled by a joint plane and one of the meshing elements of the first stage of the reducer is carried by a shaft extending in the joint plane of said housing.

[0009] According to one embodiment of the invention, the shaft carrying said meshing element is a smooth shaft.

[0010] According to one embodiment of the invention, the shaft carrying said meshing element is equipped with two anti-friction washers, each washer being interposed between the meshing element and a surface of the housing.

[0011] According to one embodiment of the invention, the rotor of the motor is surrounded by the stator.

[0012] According to one embodiment of the invention, the stator is formed by a stack of metal sheets. Brief description of the drawings

[0013] The invention will be better understood on reading the following description of exemplary embodiments, with reference to the appended drawings in which:

[0014] [Fig-1] represents a simplified partial perspective view of a mowing robot, the hood having been shown transparent to visualize the interior of the robot;

[0015] [Fig.2] represents a side view of a geared motor group of a robot according to the invention;

[0016] [Fig.3] represents an exploded view of the elements of a geared motor group of a robot according to the invention;

[0017] [Fig.4] represents a sectional view of a geared motor group of a robot according to the invention.

[0018] As mentioned above, the invention relates to an autonomous self-propelled rolling machine 1, i.e. without a driver sitting or walking behind the machine. Such an automatically moving machine is also called a robot.

[0019] In the example illustrated in [Fig. 1], the robot is a mowing robot, although the cutting blade has not been shown in the figure so as not to complicate the representation. Of course, a vacuum robot or something else, such as a load-carrying robot, could have been considered in a similar way.

[0020] This rolling machine 1 comprises a chassis 2 equipped with wheels 3 carrying the chassis 2.

[0021] In the example shown, the chassis 2 comprises a hollow body and a cover which, in the state fixed to the hollow body, delimits with said hollow body a cavity inside which are housed the groups of 4 geared motors which will be described below.

[0022] At least some of the wheels 3 of the chassis 2 are driving wheels. Thus, in the example shown, the chassis 2 is equipped with four wheels, two of which are driving wheels and two of which are idler wheels. Obviously, the number of driving wheels can change without departing from the scope of the invention.

[0023] These wheels 3 are arranged outside the cavity delimited by the chassis 2. Here, the driving wheels are of larger diameter than the idler wheels.

[0024] Each driving wheel 3 is associated with a geared motor group 4 for driving the rotation of the wheel 3. In the example of [Fig.l], two geared motor groups are therefore provided, one per driving wheel 3.

[0025] Each geared motor group 4 for driving a drive wheel 3 in rotation comprises an electric motor 5 equipped with a motor shaft 6. Conventionally, such an electric motor 5, which is here a Brushless type motor or brushless DC motor with permanent magnets, comprises a rotor 10, a stator 11 and a casing 12 surrounding the rotor 10 and the stator 11.

[0026] In the example shown in [Fig.4], the rotor 10 of the motor 5 is surrounded by the stator 11 and the stator 11 is formed by a stack of metal sheets.

[0027] The geared motor group 4 also comprises an output shaft 7 engaged with the associated driving wheel 3, and coaxial with the axis of rotation of said driving wheel 3.

[0028] The geared motor group 4 finally comprises a transmission reducer 8. The reducer 8 is housed inside a housing 9 made of synthetic material, from which at least part of the output shaft 7 projects.

[0029] In the example shown in [Fig.3], the housing 9 is formed of two shells 91 and 92 assembled by a joint plane 93.

[0030] In a manner characteristic of the invention, the motor shaft 6 and the output shaft 7 are parallel shafts each having a longitudinal axis. The longitudinal axis of the motor shaft 6 and the longitudinal axis of the output shaft 7 are coincident or spaced apart from each other by a distance at most equal to 10 millimeters. The casing 12 of the motor 5 is formed by a part of the housing 9 made of synthetic material housing the reducer 8.

[0031] The synthetic material of the housing 9 may in particular be chosen from the group of materials formed by thermoplastic polymers, in particular a polyamide or polyolefins, such as polypropylene.

[0032] The reducer 8 is a gear reducer. This reducer 8 comprises at least two reduction stages, namely at least a first and a second reduction stage.

[0033] In the example shown in [Fig. 3], where two reduction stages are shown, each reduction stage comprises a gear composed of two toothed rotating meshing elements each having an external toothing, said meshing elements of the gear of a reduction stage being engaged by meshing by said external toothing.

[0034] The external toothing of each meshing element of the reducer 8 is a helical toothing and each meshing element of the reducer 8 is formed by a toothed wheel or a pinion.

[0035] Thus, the gear 13 of the first reduction stage comprises a meshing element 131 formed by a pinion with helical external teeth engaged with the motor shaft 6 which is inserted inside the pinion, and is mounted integral in rotation with said pinion.

[0036] This meshing element 131 comes, by its helical external toothing shown at 1311, into engagement with a toothed wheel forming the second meshing element 132 of the gear 13 of the first reduction stage.

[0037] This second meshing element 132 of the gear 13 of the first reduction stage is carried by a shaft 15 extending in the joint plane 93 of the housing 9.

[0038] The shaft 15 carrying this meshing element 132 is a smooth shaft. This shaft 15 carrying the meshing element 132 is equipped with two anti-friction washers 16. Each washer 16 is interposed between the meshing element 132 and a surface of the housing 9.

[0039] This second meshing element 132 of the gear 13 of the first reduction stage comprises an external toothing 1321 in meshing engagement with the external toothing 1311 of the first meshing element 131 of the gear 13 of the first reduction stage.

[0040] The gear 14 of the second reduction stage comprises a first meshing element 141 produced here in the form of a pinion with helical external teeth shown at 1411 in the figures.

[0041] In the example shown in [Fig. 3], the second meshing element 132 of the gear 13 of the first reduction stage and the first meshing element 141 of the gear 14 of the second reduction stage are made in one piece, and the teeth 1321 and 1411 of said meshing elements 132 and 141 are helical teeth of opposite direction.

[0042] The first meshing element 141 of the gear 14 of the second reduction stage and the second meshing element 132 of the gear 13 of the first stage reduction are coaxial.

[0043] The first meshing element 141 of the gear 14 of the second reduction stage engages by its external helical toothing 1411 with the second meshing element 142 of the gear 14 of the second reduction stage, produced here in the form of a toothed wheel with external helical toothing 1421 in the same direction as that of the first gear element 131 of the gear 13 of the first reduction stage. This second meshing element 142 of the gear 14 of the second reduction stage is mounted so as to rotate integrally with the output shaft 7 in engagement with the drive wheel 3.

[0044] The reduction therefore takes place according to the reduction ratio, at the level of each pair of meshing teeth.

[0045] Obviously and in a manner known per se, the rolling machine 1 comprises a control unit for controlling the operation of the electric motors, this control unit being housed inside the chassis 2. Similarly, the rolling machine 1 is equipped with sensors helping to guide its movement. These sensors are capable of sending signals to the control unit.

[0046] Generally, such a control unit is in the form of an electronic and computer system which comprises, for example, a microprocessor and a working memory. According to a particular aspect, the control unit may be in the form of a programmable controller. In other words, the functions and steps described may be implemented in the form of a computer program or via hardware components (e.g., programmable gate arrays).In particular, the functions and steps performed by the control unit or its modules may be performed by instruction sets or computer modules implemented in a processor or controller or may be performed by dedicated electronic components or components of the programmable logic circuit type (or FPGA which is the acronym for field-programmable gate array, which literally corresponds to in-situ programmable gate array) or of the application-specific integrated circuit type (or ASIC which is the acronym for application-specific integrated circuit, which literally corresponds to application-specific integrated circuit). It is also possible to combine computer parts and electronic parts.When it is specified that the unit or means or modules of said unit are configured to carry out a given operation, this means that the unit comprises computer instructions and the corresponding execution means which make it possible to carry out said operation and / or that the unit comprises corresponding electronic components.

[0047] In practice, the operation of such a machine is similar to those of the state of the art. Control of the electric motors from the control unit makes it possible to drive and steer the robot.

Claims

Claims

1. Automatically moving rolling machine (1) without a driver sitting or walking behind the machine, also called a robot, said machine (1) comprising a chassis (2), wheels (3) carrying the chassis (2) and for each wheel (3) called a driving wheel, a geared motor group (4) for driving the wheel (3) in rotation, the geared motor group (4) for driving a driving wheel (3) in rotation comprising an electric motor (5) equipped with a motor shaft (6), an output shaft (7) engaged with the driving wheel (3) and a reducer (8) for transmitting the movement of the motor shaft (6) to the output shaft (7), the reducer (8) being housed inside a casing (9) made of synthetic material from which at least a portion of the output shaft (7) projects and the motor (5) comprising a rotor (10), a stator (11) and a casing (12) surrounding the rotor (10) and the stator (11), characterized in that the reducer (8) comprises at least two reduction stages,in that each reduction stage comprises a gear (13; 14) composed of at least two toothed rotating meshing elements (131, 132; 141, 142) each having an external toothing (1311, 1321; 1411, 1421) and meshing with said external toothing, in that the motor shaft (6) and the output shaft (7) are parallel shafts, in that the longitudinal axes of the motor shaft (6) and the output shaft (7) are coincident or spaced apart from each other by a distance at most equal to 10 millimeters, and in that the casing (12) of the motor (5) is formed by a part of the housing (9) made of synthetic material housing the reducer (8).,

2. Rolling machine (1) according to claim 1, characterized in that the external toothing (1311, 1321, 1411, 1421) of each meshing element (131, 132, 141, 142) of the reducer (8) is a helical toothing.

3. Rolling machine (1) according to one of claims 1 or 2, characterized in that each meshing element (131, 132, 141, 142) of the reducer (8) is formed by a toothed wheel or a pinion.

4. Rolling machine (1) according to one of claims 1 to 3, characterized in that one (132) of the meshing elements (131, 132) of the first reduction stage and one (141) of the meshing elements (141, 142) of the second reduction stage are made in one piece and in that the teeth (1321, 1411) of said meshing elements (132, 141) made from a single piece are helical teeth in opposite directions.

5. Rolling machine (1) according to one of claims 1 to 4, characterized in that the housing is formed of two shells (91, 92) assembled by a joint plane (93) and in that one (132) of the meshing elements (131, 132) of the first stage of the reducer (8) is carried by a shaft (15) extending in the joint plane (93) of said housing (9).

6. Rolling machine (1) according to claim 5, characterized in that the shaft carrying said meshing element (132) is a smooth shaft.

7. Rolling machine (1) according to one of claims 5 or 6, characterized in that the shaft (15) carrying said meshing element (132) is equipped with two anti-friction washers (16), each washer (16) being interposed between the meshing element (132) and a surface of the housing (9).

8. Rolling machine (1) according to one of claims 1 to 7, characterized in that the rotor (10) of the motor (5) is surrounded by the stator (11).

9. Rolling machine (1) according to one of claims 1 to 8, characterized in that the stator (11) is formed by a stack of metal sheets.

Images