Autonomous working device and drive unit for autonomous working device

Abstract

The present invention relates to a working device (1) comprising at least one housing (2), at least one drive unit (3) and at least one control device, wherein the drive unit (3) comprises at least one motor (4) and at least one drive wheel (5), wherein the working device (1) is designed and configured to move autonomously in a processing environment (6).An autonomous work device (1), in particular a cleaning device, in which operational safety is increased, is realized by the fact that the drive unit (3) has at least one self-locking gearbox (8), that the gearbox (8) has at least one first tooth element (11) with a first toothing (12) and at least one second tooth element (14) with a second toothing (15), that the first tooth element (11) is arranged inside the second tooth element (14), that the first toothing (12) is at least partially engaged with the second toothing (15), and that the drive wheel (5) can be driven by the motor (4) via the gearbox (8).

Description

[0001] The invention relates to a working device, in particular a cleaning device for autonomously cleaning a processing environment, comprising at least one housing, at least one drive unit, and at least one control device. The drive unit has at least one motor and at least one drive wheel. The working device is designed and configured to move autonomously within a processing environment.

[0002] Generic work devices are known in the prior art in a variety of designs. Such work devices are designed to move autonomously within a processing environment and perform work tasks. Examples of such work devices include cleaning devices that perform cleaning tasks within a processing environment, transport robots in warehouse logistics, or security robots used for surveillance purposes. A cleaning device is designed, for example, as a vacuum robot, a mop robot, or a vacuum and mop robot. Such work devices typically have at least one control device comprising a data processing device and, with a plurality of sensors, ensuring navigation of the work device within the processing environment and controlling the completion of work tasks within the processing environment.

[0003] Tools designed as cleaning equipment suitable for commercial applications typically have a larger volume, heavier weight, higher movement speeds, and greater power than cleaning equipment used in households. Furthermore, increased operational safety requirements apply, for example, with regard to the risk of falling on edges and stairs, as well as contact with people or other work equipment.

[0004] For the operational safety of a work device, it is therefore of increased importance that, when an obstacle or a critical operating situation is detected, an immediate reaction of the moving work device is required in order to prevent damage to the area surrounding the work device and / or damage to the work device.

[0005] In conventional work tools, the installation space required for the required basic components is typically very large. Due to the space required for these basic components, the installation areas for additional equipment components, such as energy storage devices, electronics, work tools, and sensors, are either limited or the size of the work tool must be increased accordingly to accommodate all components in its entire construction volume.

[0006] A mobile cleaning device is known from US 2018 / 0184875 A1. The cleaning device comprises a body with a controller, a wheel cover mounted on the body, a drive module coupled to the wheel cover and movable up and down, a drive wheel coupled to the drive module and rotatable by supplying drive power from the drive module, a vertically extending guide rod coupled to the wheel cover for guiding an up and down movement of the drive module, and a spring element. The spring element surrounds the guide rod and is connected to the wheel cover and the drive module to absorb shocks as the drive module moves up and down.

[0007] From US 9,950,586 B2, a cleaning robot is known which can free itself from a position from which it cannot be moved any further. The cleaning robot comprises a body and a drive unit for driving the body. The drive unit comprises a first drive motor and a second drive motor for generating drive power, a drive wheel which rotates when drive power is supplied from the first drive motor, and a wheel frame which rotatably supports the drive wheel and which is movable between a first position and a second position with respect to a motor shaft of the first drive motor. The wheel frame rotates in at least a section between the first position and the second position when the drive power is supplied to the wheel frame from the second drive motor.

[0008] The invention is based on the object of specifying a working device, in particular for commercial applications, in which operational safety is increased and at the same time the size of the working device is reduced.

[0009] The aforementioned object is achieved in a generic work device according to the characterizing part of claim 1 in that the drive unit has at least one self-locking gear. The gear has at least one first toothed element with a first, in particular annular, toothing and at least one second toothed element with a second, in particular annular, toothing. The first toothed element is arranged within the second toothed element and the first toothing is at least partially in engagement with the second toothing. The drive wheel can be driven by the motor via the gear. The first toothed element is elastically deformable, in particular radially elastically deformable. The gear is advantageously arranged in the drive path between the motor and the drive wheel.

[0010] The work device is designed for autonomous movement within a processing environment and for completing work tasks. For example, the work device is designed as a cleaning device, a transport device in transport logistics, or a safety robot for environmental monitoring. Preferably, the work device is designed as a cleaning device for cleaning a processing environment. The work device designed as a cleaning device is advantageously a cleaning device with a suction and / or wiping function, in particular a vacuum robot, a wiping robot, or a vacuum and wiping robot.

[0011] In particular, the work device has at least one control device and a plurality of sensors that control the autonomous movement and cleaning of a processing environment by the cleaning device. The control device preferably has at least one data processing device with at least one processor and at least one memory.

[0012] For example, at least or exactly two drive units are arranged on the housing of the implement, each comprising at least one motor, in particular an electric motor, at least one self-locking gear, and at least one drive wheel. The motor is preferably a brushless DC motor. The two motors of the drive units can be controlled independently of one another. Each motor drives at least indirectly, or exactly, one drive wheel via the gear.

[0013] Each drive unit is, for example, at least partially movable essentially vertically, i.e., essentially orthogonal to a surface of the processing environment, arranged on or at least partially within the housing, in particular an underside of the housing. Each drive unit preferably has a drive unit housing, which is advantageously attached to the housing of the working device.

[0014] Furthermore, the working device has at least one energy storage device, which is designed to supply power to the working device, in particular to supply power to the control device and in particular to a working tool, in particular a cleaning tool, and is electrically connected in the housing. For example, the energy storage device is designed as an accumulator with at least one cell, in particular a plurality of cells.

[0015] Self-locking of the transmission of a drive unit according to the understanding of the present invention means that the transmission stops when torque is no longer acting on the input side, regardless of whether torque is still acting on the output side or not. Self-locking could also be referred to as self-braking. The transmission is designed in particular such that torque on the output side cannot cause any movement of the transmission. The transmission advantageously stops when torque is no longer introduced from the input side. The transmission is designed in particular such that it cannot be reversed on the output side.

[0016] The transmission advantageously has at least one drive side, to which, for example, the motor is connected, and at least one output side, to which, for example, the drive wheel is connected. The transmission is preferably designed to be statically and dynamically self-locking, so that the transmission remains stationary, in particular when no torque is introduced from the drive side, even if torque is still applied to the output side - in this case, the drive wheel - and such that it cannot be moved from the stationary state by a torque introduced at the output side - in this case, the drive wheel. The transmission has at least one first toothed element with a first toothing, in particular annular, and at least one second toothed element with a second toothing, in particular annular. The first toothed element is arranged to be movable within the second toothed element.For example, the first toothed element is rotatably mounted within the second toothed element. The second toothed element is preferably arranged in a stationary manner. The first toothing is at least partially engaged with the second toothing. The first toothing and the second toothing are preferably annular, thus preferably forming a closed ring.

[0017] For example, it is provided that the first toothed element rolls with its first toothing on the second toothing of the second toothed element, or that the first toothing moves relative to the second toothing during a movement of the gear. The interaction of the toothings is preferably designed in such a way that the self-locking of the gear is thereby realized.

[0018] In particular, it is provided that the first toothing is an external toothing and the second toothing is an internal toothing. For example, the first tooth element is designed as a toothed ring with external toothing and / or the second tooth element is designed as a toothed ring with internal toothing. In particular, it is also provided that the first tooth element is designed as a toothed disk.

[0019] Particularly for reducing installation space, it has proven advantageous to arrange a motor shaft coaxially with the wheel axle of the drive wheel. The motor is spatially arranged in the drive unit in line with the wheel axle of the drive wheel, although the motor shaft and the wheel axle of the drive wheel are not directly connected to each other. The self-locking gear, for example, a strain wave gear, is arranged between the motor and the drive wheel to ensure an emergency stop when the motor is switched off.

[0020] The motor of the drive unit(s) can be switched off by the control device, for example, using information, i.e., data, signals, or measured values, from an environmental sensor system. The environmental sensor system comprises, for example, at least one optical sensor, in particular for monitoring the environment, and / or at least one distance sensor, which measures, in particular, the distance to a surface of the processing environment in order to detect building edges or stairs and prevent falls.

[0021] The present invention therefore has the advantage over the prior art that when the motor is switched off, the drive wheel is immediately blocked by the self-locking mechanism of the gear. Torque emanating from the drive wheel does not result in any further movement of the gear. Furthermore, the drive wheel(s) cannot rotate when the implement is stationary. Due to the positive engagement of the intermeshing teeth, no rotation can be initiated into the gear via the drive wheel, as the tooth flanks of the teeth of the first and second gearing press against each other. These properties of the gear eliminate the need for a special emergency brake, as all that is required to bring the implement to an emergency stop is to de-energize the motor.Because a special emergency brake is no longer required, the required installation space and thus the size and weight of the implement are reduced compared to conventional implements.

[0022] As explained, the invention provides that the first toothed element is elastically deformable, in particular radially elastically deformable. The first toothed element is coupled, for example, to the output shaft of the transmission or to the wheel axle of the drive wheel.

[0023] The elastically deformable, first toothed element in the gear mechanism preferably implements the self-locking of the gear mechanism. The first toothed element is, for example, movably held in the gear mechanism and, during movement, only a portion of its teeth engage with corresponding teeth of the second toothed element. For example, the first toothed element, e.g., in the form of a toothed ring or toothed disk, rolls with its teeth on corresponding teeth in the gear mechanism. In particular, it is provided that the first toothed element performs a wobbling movement within the second toothed element. Advantageously, during movement in the second toothed element, the toothed element is at least partially elastically deformed. It is preferably provided that the toothed element is radially elastic, i.e., deformable, for example, with respect to its diameter or with respect to its outer contour.In particular, an elastic deformation and a wobbling movement of the first tooth element occurs.

[0024] A further embodiment of the working device provides that a tooth engagement between the first toothing and the second toothing can be effected by means of at least one guide means, in particular that the guide means has at least or exactly one rolling body, preferably at least or exactly two rolling bodies, or at least or exactly three rolling bodies, or at least one rotatable disc.

[0025] The guide means preferably guides the first toothed element within the transmission. In particular, the guide means acts on the first toothed element such that the guide means brings about a, in particular local, engagement of teeth of the first toothing with teeth of the second toothing. For example, the guide means brings about an engagement between the first toothing and the second toothing in the circumference of a contact surface between the guide means and the first toothed element. Preferably, the guide means acts on the first toothed element such that the first toothing moves relative to the second toothing when the transmission is driven by the motor. Advantageously, the guide means is movable, in particular rotatable, by the motor.

[0026] For example, the guide means is designed as a rolling body, e.g. as a roller or roller bearing, and acts on the first toothed element from an inner side. The first toothed element is designed in particular as a toothed ring with external teeth. The first toothing of the first toothed element is pressed by the rolling body into engagement with the second toothing of the second toothed element. Preferably, the rolling body is held rotatably about the motor shaft of the motor, wherein the motor shaft does not coincide with a rolling axis of the rolling body. As a result, the rolling body can, for example, cause the first toothed element to roll on the second toothed element and thus cause a relative movement between the first and second toothing. The rotation resulting from the movement of the first toothed element is transmitted, for example, to the wheel axle of the drive wheel.The rotation is transmitted, for example, by means of a plain bearing described below, in particular to enable a wobbling motion of the first toothed element. It is also provided that a counterweight is connected to the rolling element to compensate for any imbalance caused by the rotation of the rolling element.

[0027] Preferably, the guide means comprises at least two rolling elements, and the rolling elements are held such that they are rotatable about a common axis positioned between the rolling elements. Each rolling element itself is rotatable about a rotation axis. For example, rotation of the rolling elements - including the respective rotation axis - about the common axis of the rolling elements can be effected by the motor. Rotation of each rolling element about its own rotation axis is achieved, for example, by rolling, in particular on an inner surface of the first toothed element. The rolling elements are arranged such that, opposite one another, they bring the first toothing of the first toothed element into engagement with the second toothing of the second toothed element. The first toothing engages, for example, with the second toothing at least in the region of the rolling elements or only in the region of the rolling elements.It is provided that a part of the first toothing and the second toothing in the areas between the rolling bodies is at least partially in engagement with each other, in particular depending on the wobbling movement of the first tooth element relative to the second tooth element.

[0028] As an alternative to the rolling elements, the engagement of the first toothing with the second toothing can be effected by a rotatably mounted disk, in particular an eccentrically mounted disk or an oval disk. The disk is preferably arranged in the gear mechanism within the first toothed element, so that rotation of the disk caused by the motor causes an engagement, in particular a local engagement, of the first toothing with the second toothing. Preferably, the guide means, for example a disk or a ring, slides along the first toothed element.

[0029] According to a further embodiment, it has proven particularly advantageous if it is provided that between the first toothing and the second toothing approximately 5% to 85% of the total number of teeth of the first toothing are at least partially, in particular completely, in engagement with one another.

[0030] In particular, approximately 25% to 75% of the total number of teeth of the first gearing are at least partially, and in particular completely, engaged with the second gearing. This ensures both advantageous power transmission and self-locking.

[0031] A further embodiment of the tool provides that force is transmitted between the first toothed element and the second toothed element only via one to 15 teeth. It is provided that, in particular even when more than one to 15 teeth are engaged, force is actually transmitted only via the limited number of teeth. For example, it is also provided that force is transmitted via at least or exactly one tooth, or via at least or exactly two teeth, or via at least or exactly three teeth. Preferably, force is also transmitted between the first toothing and the second toothing via 1.7% to 17% of the teeth of the first toothing.

[0032] In particular, in order to bring about an advantageous relative movement between the first tooth element and the second tooth element, a further embodiment provides for the first toothing and the second toothing to have a different number of teeth. For example, it is provided that the first toothing has at least or exactly one tooth less, at least or exactly two teeth less, or at least or exactly three teeth less than the second toothing. This results in tooth overlap between the first tooth element and the second tooth element or between the first toothing and the second toothing, which occurs in the intermediate space or spaces in which the guide means does not press the two toothings into engagement with one another. The tooth overlap is accompanied in particular by a deformation of the first tooth element, which is advantageously designed to be correspondingly deformable due to its material properties and geometry.It is preferably provided that the tooth jump is caused by the wobbling movement and / or the deformation of the first tooth element.

[0033] For gears with a single tooth difference and two rolling elements as the guide element, the position of the possible tooth overlap can be determined by the position of the guide element and the first tooth element at the time of assembly. The assignment of the tooth overlap position to one of the two areas in which the teeth do not mesh remains constant as long as the guide element and the first tooth element are not removed.

[0034] A design with a two-tooth difference between the gear teeth is subject to the same conditions in a system with two rolling elements as the guide. However, during assembly, a decision can be made whether the tooth jump should be in a single area between the two meshing areas, or whether a tooth jump of one tooth pitch should occur in each of the two areas between the meshing areas. The difference lies in the required deformation, because a tooth jump of two or more teeth in just one area requires a greater deformation movement of the first tooth element. This can influence the service life of the gear, depending on the material and / or the magnitude of the transmitted torque.

[0035] It is particularly advantageous for the first toothing to have exactly one tooth less, for example 59 teeth, than the second toothing, for example 60 teeth. During continuous movement of the guide means, the first tooth element rotates by one tooth width relative to the second toothing when at least one toothed region between the two toothings has completed one revolution in the second toothing. After 59 revolutions of the toothed region, the first tooth element has then rotated once around its own axis - possibly taking into account any wobbling movement. If the guide means is designed as an elliptical disk that slides along the inside of the first tooth element, at least one toothed region has completed one revolution after one rotation of the disk.If, for example, the guide means has two rotatable rolling elements within the first toothed element, the first toothed element rotates by one tooth width relative to the second toothing for each revolution of the rolling elements around the common axis arranged between the rolling elements, thus completing a full revolution after 59 revolutions of the rolling elements around the common axis arranged between the rolling elements or after 59 revolutions of the motor axis. The rolling elements are coupled to the motor and can be rotated by the motor about an axis positioned between the rolling elements. This results in a gear reduction ratio of 59:1. Each rolling element rotates around its respective axis of rotation with any number of revolutions when rotating around the common axis, in particular depending on its diameter. The drive wheel can be rotated with the first toothed element, for example via at least one plain bearing.The second tooth element is advantageously held stationary.

[0036] Due to the different number of teeth, the first toothing moves relative to the second toothing due to the tooth overlap. The resulting rotation of the first tooth element is transmitted to the drive gear as a rotary motion, for example, via at least one plain bearing.

[0037] Preferably, the first toothed element is designed as a toothed ring and the second toothed element is designed as a toothed ring. The first toothed ring is held in the second toothed ring and is pressed into engagement with the second toothing of the second toothed ring having an internal toothing by the guide means, for example in the form of two rolling elements acting opposite one another on the inner circumference of the first toothed ring. The first toothed ring and the second toothed ring advantageously have a different number of teeth so that the tooth overlap described above occurs when the guide means moves. The second toothed ring is held stationary so that when the guide body rotates caused by the motor, the first toothed ring rotates in the second toothed ring. The movement of the first toothed ring in the second toothed ring is transmitted to the wheel axle of the drive wheel. The gear system designed in this way has, for example, a reduction ratio of 59:1 and is self-locking.

[0038] In order to prevent damage to the components of the transmission, in particular under shock loads, a further embodiment provides that the first toothed element and / or the second toothed element is made at least partially, in particular completely, from polyoxymethylene (POM), polypropylene carbonate (PPC), polyamide (PA), polypropylene (PP), a thermoplastic elastomer and / or a silicone. For example, the first toothed element is made as a first toothed ring with external teeth from polyoxymethylene (POM), polypropylene carbonate (PPC), polyamide (PA), polypropylene (PP), a thermoplastic elastomer and / or a silicone and / or the second toothed element is made as a second toothed ring with internal teeth from polyoxymethylene (POM), polypropylene carbonate (PPC), polyamide (PA), polypropylene (PP), a thermoplastic elastomer and / or a silicone.

[0039] In order to advantageously transmit the rotation of the first toothed element in the transmission to the axle of the drive wheel, a further embodiment provides that the transmission has at least one driver, and that the driver is coupled to the first toothed element. The driver is advantageously connected to the wheel axle of the drive wheel. For example, the driver has a disc-shaped base body. For example, the first toothed element is designed as a first toothed ring with external teeth, and the driver is arranged at least partially within the toothed ring, in particular without interfering with the movement of the guide means.

[0040] It has proven advantageous if the driver is coupled to the first toothed element, in particular the first toothed ring, by means of at least one plain bearing. This use is advantageous if the first toothed element deforms during rotation, so that the deformation and any wobbling movement do not affect the driver. For example, the driver has a disc-shaped base body from which at least one pin extends in the radial direction. The pin engages with a pin bearing arranged on the inner circumference of the first toothed element, in particular the first toothed ring, for example in the form of two projections arranged parallel to one another. The pin and the pin bearing form the plain bearing, which compensates for deformations in the radial direction in particular, but transmits rotation to the driver and thus to the drive wheel.

[0041] Advantageously, the driver is connected to the first toothed element by at least four plain bearings, which are particularly evenly distributed over the circumference. This improves the power transmission to the driver.

[0042] In order to advantageously reduce the number of components required for the transmission, a further embodiment provides for the first toothed element to be formed integrally with the driver. In particular, it is provided that the first toothed element and the driver are connected to one another via elastic elements. The elastic elements compensate in particular for a deformation and / or a wobbling movement of the first toothed element, in particular of the first toothed ring, in the radial direction, but transmit the rotation of the first toothed element to the driver. For example, the first toothed element and the driver are manufactured as a two-component component, for example with a harder component for the driver and the first toothed element and a softer component for the elastic elements in between.

[0043] This design has the advantage that the number of components is reduced and the loss-making friction in the plain bearings is avoided.

[0044] A further embodiment of the implement provides that the drive unit is mounted on the implement so as to be movable, for example pivotable and / or translationally movable. Each work unit is movably attached, for example, to a bottom side of the implement's housing using a pivot bearing. For example, it is provided that the drive unit is pressed into a pivoted position against the bottom side of the implement by a spring preload between the housing and an arm that can swing around the pivot bearing. Alternatively, it is provided that the drive unit is mounted on a bottom side of the implement's housing so as to be translationally movable. The translational mobility is realized, for example, by means of bending beams and / or plain bearings.

[0045] In order to de-energize the motor in operationally critical situations, the control device must be able to identify such situations. For this purpose, according to a further embodiment, the implement has at least one environmental sensor system. The control device is configured to de-energize at least one motor or all motors of all drive units using information, e.g., at least one measured value, at least one signal, or data, from the environmental sensor system if the information indicates an operationally critical situation, for example, damage to the environment or the implement.

[0046] The environmental sensor system comprises at least one sensor, preferably a plurality of sensors, with which the environment of the implement can be monitored. For example, the environmental sensor system comprises at least one optical sensor and / or at least one acoustic sensor and / or at least one electromagnetic sensor.

[0047] For example, the control unit processes information from the environmental sensor system and can identify a critical operating situation that requires the engine to be switched off based on the exceedance of threshold values and / or a profile of criteria of predefined situations.

[0048] The invention further relates to a drive unit for a working device, wherein the drive unit is designed in particular according to one of the described exemplary embodiments. The drive unit has, for example, at least one motor and at least one drive wheel and is characterized in that at least one self-locking gear is present, wherein the drive wheel can be driven by the motor via the gear. The gear has at least one first toothed element with a first toothing, in particular annular, and at least one second toothed element with a second toothing, in particular annular. The first toothed element is arranged within the second toothed element. The first toothing is at least partially in engagement with the second toothing. The first toothed element is elastically deformable, in particular radially elastically deformable.

[0049] Further advantageous embodiments of the invention emerge from the following description of the figures and the dependent subclaims.

[0050] They show: Fig. 1 shows an embodiment of a working device designed as a cleaning device in a perspective view, Fig. 2 shows a first embodiment of a drive unit for a working device in a section, and Fig. 3 shows the embodiment of the drive unit for a working device according to Fig. 2 in another cut.

[0051] In In the various figures of the drawing, identical parts are always provided with the same reference symbols.

[0052] With regard to the following description, it is claimed that the invention is not limited to the exemplary embodiments and not to all or several features of described combinations of features, but rather each individual partial feature of the / each exemplary embodiment is also important for the subject matter of the invention, even independently of all other partial features described in connection therewith, and also in combination with any features of another exemplary embodiment.

[0053] Fig. 1 shows an embodiment of a working device 1 in a perspective side view. The working device 1 comprises a housing 2, two drive units 3 arranged on the underside of the housing 2, and at least one control device arranged in the housing 2. The working device 1 is designed as a cleaning device, namely as a vacuum robot, and can move autonomously within a processing environment 6.

[0054] The working device 1 according to Fig. 1 has an environmental sensor system 24 with which the processing environment 6 can be continuously detected. The control device is configured to de-energize at least one motor 4 or all motors 4 of all drive units 3 using information, e.g., at least one measured value, at least one signal, or data, from the environmental sensor system 24 if the information indicates an operationally critical situation, for example, damage to the environment or the work device 1.

[0055] An embodiment of a motor 4 with a gearbox 8 for a drive unit 3 for the working device 1 is shown in the Fig. 2 and Fig. 3 shown. Fig. 2 shows a first section through the embodiment along a motor shaft 9 of the motor 4, Fig. 3shows a second section through the exemplary embodiment orthogonal to the motor shaft 9. Each drive unit 3 has a motor 4, a drive wheel 5, and a self-locking gear 8. The self-locking gear 8 is arranged between the motor 4 and the drive wheel 5 such that the drive wheel 5 can be driven by the motor 4 via the gear 8. The motor 4 is designed as a brushless DC motor. The gear 8 has a gear housing 8a in which the components of the gear 8 are held.

[0056] The gearbox 8 according to Fig. 2 and 3 is self-locking, in particular statically and dynamically self-locking, so that it can be moved by the motor 4, in particular by the motor shaft 9 of the motor 4, i.e. from the drive side, but cannot be moved from the output side, namely the wheel axle 10 of the drive wheel 5. The wheel axle 10 is in Fig. 2 only presented as an approach.

[0057] The gear mechanism 8 has, in particular for implementing self-locking, an elastically deformable first toothed element 11 with a first toothing 12 designed as an external toothing. The first toothed element 11 is designed as a first toothed ring. The first toothing 12 of the first toothed element 11 interacts at least locally, namely in two oppositely arranged regions 13, with a second toothing 15 of a second toothed element 14. The second toothed element 14 is designed as a second toothed ring with internal toothing, which here forms the second toothing 15. The second toothed element 14 is fixedly connected to the housing 8a of the gear mechanism 8 or is formed integrally with the housing 8a of the gear mechanism 8.

[0058] The motor shaft 9 of the motor 4 is arranged coaxially in the axial direction one behind the other with the wheel axle 10 of the drive wheel 5. A guide bearing 16 is connected to the motor shaft 9 in a rotationally fixed manner, on which a guide means 17 in the form of two rolling elements 17a is arranged. The rolling elements 17a are rotatable about the motor shaft 9 by means of the motor 4 and the guide bearing 16, with each rolling element 17a in turn being rotatably mounted about a rolling element axis R on a bearing projection 7 of the guide bearing 16. The rolling elements 17a are arranged in the gear 8 such that they effect a tooth engagement of the first toothing 12 with the second toothing 15 at least in the opposite regions 13. In the regions of the toothings 12, 15 arranged between the regions 13, the toothings 12, 15 do not mesh or only partially mesh. According to Fig. 2the teeth 12, 15 engage at least partially with each other in the area shown on the right between the areas 13.

[0059] In particular, in the areas arranged between the areas 13, no force is transmitted between the toothings 12, 15. The local engagement of the first toothing 12 in the second toothing 15 as well as the non-engagement or only partial engagement of the toothings 12, 15 in the areas in between is Fig. 3 shown schematically.

[0060] In order to achieve the engagement of the toothings 12, 15 in the regions 13, the first tooth element 11 designed as a first toothed ring is elastically designed and is elastically deformed by the action of the guide means 17 or the action of the rolling bodies 17a.

[0061] In this embodiment according to Fig. 2 and Fig. 3The first toothing 12 has exactly one tooth less than the second toothing 15. The first toothing 12 has 59 teeth, and the second toothing 15 has 60 teeth. If the guide means 17 is now rotated by the motor 4 around the motor shaft 9, the rolling elements 17a roll on an inner circumference 18 of the first tooth element 11 and engage the first toothing 12 and the second toothing 15. When the guide element 17 or the rolling elements 17a rotate around the motor shaft 9, the deformation of the first tooth element 11, and thus also the regions 13 in which the tooth engagement is realized, "migrates" circumferentially within the second tooth element 14. Due to the different number of teeth, a tooth jump occurs in the regions in which the toothings 12, 15 are not in engagement, so that the first toothing 12 moves relative to the second toothing 15 and the first tooth element 11 thereby rotates within the second tooth element 14.In this embodiment, this rotation is caused by the different number of teeth, which simultaneously realizes a reduction ratio of 59:1.

[0062] To transmit this rotational movement of the first toothed element 11 to the wheel axle 10 of the drive wheel 5, a driver 19 is arranged and centrally mounted in the gear 8. The driver 19 is positively connected to the wheel axle 10 of the drive wheel 5 and transmits its movement to the wheel axle 10. The driver 19 has a substantially disc-shaped base body 20.

[0063] Four journals 21, evenly distributed around the circumference, extend radially from the base body 20 of the driver 19. The journals 21 interact in a form-fitting manner with four journal bearings 22, also evenly distributed around the circumference and arranged on the first toothed element 11. Each journal bearing 22 consists of two projections 22a arranged essentially parallel to one another, which extend radially inward from the first toothed element 11. The journals 21 and the journal bearings 22 together form a total of four plain bearings 23, evenly distributed around the circumference. The plain bearings 23 have the function of decoupling the wobbling movement and deformation of the first toothed element 11 from the rotational movement, so that only the pure rotational movement of the first toothed element 11 is transmitted to the driver 19. The plain bearings 23 thus ensure radial compensation without interrupting the power transmission.

[0064] The gear unit 8 designed in this way has a self-locking feature, so that rotation of the wheel axle 10 stops immediately when the motor 4 is de-energized. The self-locking feature of the gear unit 8 is achieved in that, when a torque is introduced via the wheel axle 10, the force would be transmitted via the plain bearings 23 to the first toothed element 11, but the first toothing 12 would then be unable to move relative to the second toothing 15 because the tooth flanks of the teeth of the toothings 12, 15 are in contact with one another. Such a gear unit is also referred to as a strain wave gear unit. Since the gear unit 8 is self-locking, i.e., cannot be set into rotation via the wheel axle 10 and stops when the motor 4 is switched off, the self-locking gear unit 8 fulfills the function of an emergency brake for the implement 1. List of reference symbols

[0065] 1Working device 2Housing 3Drive unit 4Motor 5Drive wheel 6Machining environment 7Bearing projection 8Gearbox 8aGearbox housing 9Motor shaft 10Wheel axis of 5 11First tooth element 12Toothing of 11 13Area 14Second tooth element 15Toothing of 14 16Guide bearing 17Guide means 17aRolling element 18Inner circumference of 11 19Drive element 20Base body 21Template 22Template bearing 22aProtrusion 23Plain bearing 24Environmental sensor system RRolling body axis

Claims

1. Work device (1), with at least one housing (2), at least one drive unit (3) and at least one control device, wherein the drive unit (3) has at least one motor (4) and at least one drive wheel (5), wherein the work device (1) is designed and configured to move autonomously in a processing environment (6), and the drive unit (3) has at least one self-locking gear (8), that the gear (8) has at least one first tooth element (11) with a first toothing (12) and at least one second tooth element (14) with a second toothing (15), that the first tooth element (11) is arranged within the second tooth element (14), that the first toothing (12) is at least partially engaged with the second toothing (15), and that the drive wheel (5) can be driven by the motor (4) via the gear (8), and characterized in that the first tooth element (11) is elastically deformable, in particular radially elastically deformable.

2. Work device (1) according to claim 1, characterized in that a tooth engagement between first toothing (12) and second toothing (15) can be effected by means of at least one guide means (17), in particular that the guide means (17) has at least or exactly one rolling element (17a), preferably at least or exactly two rolling elements (17a), or at least or exactly three rolling elements (17a), or at least one rotatable disc.

3. Work device (1) according to one of claims 1 to 2, characterized in that between first toothing (12) and second toothing (15) approximately 5% to 85%, in particular approximately 25% to 75%, of the total number of teeth of the first toothing (12) are at least partially engaged with each other.

4. Work device (1) according to one of claims 1 to 3, characterized in that a force transmission between the first tooth element (11) and the second tooth element (14) occurs over one to 15 teeth, in particular over at least or exactly one tooth or at least or exactly two teeth or at least or exactly three teeth.

5. Work device (1) according to one of claims 1 to 4, characterized in that the first toothing (12) and the second toothing (15) have a different number of teeth, in particular that the first toothing (12) has at least or exactly one tooth less, at least or exactly two teeth less, at least or exactly three teeth less than the second toothing (15).

6. Work device (1) according to one of claims 1 to 5, characterized in that the first tooth element (11) and / or the second tooth element (14) are / is at least partially, in particular completely, made of polyoxymethylene (POM), polypropylene carbonate (PPC), polyamide (PA), polypropylene (PP), a thermoplastic elastomer and / or a silicone.

7. Work device (1) according to one of claims 1 to 6, characterized in that the gear (8) has at least one driver (19), and that the driver (19) is coupled with the first tooth element (11), in particular that the driver (19) is connected to the wheel axle (10) of the drive wheel (5).

8. Work device (1) according to claim 7, characterized in that the driver (19) is coupled with the first tooth element (11) by means of at least one plain bearing (23), in particular by means of at least four plain bearings (23).

9. Work device (1) according to claim 8, characterized in that the first tooth element (11) is formed integrally with the driver (19), in particular that the first tooth element (11) and the driver (19) are connected to each other via elastic elements.

10. Work device (1) according to one of claims 1 to 9, characterized in that the drive unit (3) is movably held on the work device (1), for example pivotable and / or translationally movable, in particular that a translational movability is realized by means of bending beams and / or plain bearings.

11. Work device (1) according to one of claims 1 to 10, characterized in that at least one environment sensor system (24) is present, and that the control device is designed and configured to de-energize the motor (4) using information from the environment sensor system (24) in order to brake the work device (1).

12. Drive unit (3) for a work device (1), in particular according to one of claims 1 to 11, comprising at least one motor (4) and at least one drive wheel (5), characterized in that at least one self-locking gear (8) is present, that the gear (8) has at least one first tooth element (11) with a first toothing (12) and at least one second tooth element (14) with a second toothing (15), that the first tooth element (11) is arranged within the second tooth element (14), that the first toothing (12) is at least partially engaged with the second toothing (15), and that the drive wheel (5) can be driven by the motor (4) via the gear (8), and that the first tooth element (11) is elastically deformable, in particular radially elastically deformable.

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