AUTONOMOUS WORK DEVICE AND DRIVE UNIT FOR AN AUTONOMOUS WORK DEVICE

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] US 2005 / 002864 A1 discloses a generic autonomous commercial vehicle with an emergency braking system. The subject matter of US 2005 / 002864 A1 provides that, during an emergency braking operation, a drive unit of the commercial vehicle is shut down, so that the drive unit generates a braking torque based on its engine.

[0004] 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.

[0005] 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.

[0006] The invention is therefore based on the object of specifying a working device, in particular for commercial applications, in which operational safety is increased.

[0007] The aforementioned object is achieved with a generic work device according to the characterizing part of claim 1. An emergency braking system is provided. The emergency braking system has at least one braking element and is controllable by the control device of the work device, i.e., for example, can be triggered and released or deactivated. After triggering the emergency braking system, the braking element interacts positively with at least one component of the drive unit that moves during operation of the work device to achieve a braking effect, such that the movement of the component is stopped or blocked. As a result, movement of the work device is stopped or blocked. The moving component is, in particular, a component that moves, in particular rotates, to effect a movement of the work device, for example the rotor of a motor, a motor shaft, a brake body arranged on the motor shaft, or a drive wheel.The braking element advantageously interacts directly or indirectly with the component in a form-fitting manner to stop the movement of the component or to block the component. An indirect interaction is achieved, for example, when the braking element interacts in a form-fitting manner with a component that is firmly connected to the component to be stopped. The form-fitting engagement is created, for example, in such a way that rotation of the component with which the braking element interacts in a form-fitting manner is stopped.

[0008] The work device is designed for autonomous movement within a processing environment and for performing work tasks. For example, the work device is designed as a cleaning device, a transport device in transport logistics, or a security robot for environmental monitoring.

[0009] The work device is preferably 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. The work device has, in particular, 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.

[0010] The implement preferably has at least one second control device. The second control device advantageously has at least one data processing device with at least one processor and at least one memory. The second control device is designed and configured to assume at least some or all of the tasks of the first control device as a redundant system in the event of a malfunction in the first control device. In particular, the second control device is also designed to control, in particular to trigger and release, the emergency braking system.

[0011] For example, at least or exactly two drive units are arranged on the housing of the implement, each having at least one motor, in particular an electric motor, and at least one drive wheel. The motor is preferably a brushless DC motor, in particular a brushless DC motor designed as an external rotor. The two motors of the drive units can be controlled independently of one another. Each motor at least indirectly drives at least or exactly one drive wheel. For example, a gear unit is also provided between the motor and the drive wheel of a drive unit.

[0012] Each drive unit is, for example, at least partially substantially vertically movable, i.e. substantially orthogonal to a surface of the processing environment, arranged on or at least partially in the housing, in particular an underside of the housing.

[0013] 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.

[0014] The implement has at least one emergency or safety braking system. The emergency braking system is preferably provided in addition to a braking system or braking function for the usual reduction of speed during operation. Typically, a braking function in autonomous implements is implemented via the motor of the drive unit or the motors of the drive units, by controlling each motor to move in the opposite direction of movement until the implement comes to a standstill, or by switching it off.

[0015] The emergency braking system can be triggered 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, in particular, measures the distance to a surface of the processing environment in order to detect building edges or stairs and prevent falls.

[0016] The emergency braking system has at least one or exactly one braking element. The braking element is designed and arranged such that, after the emergency braking system is triggered, it is moved in such a way that it comes into positive engagement with at least one component moving during operation of the implement. The positive engagement between the braking element and the moving component prevents the moving component from further movement, namely, it blocks it. The braking effect occurs when the moving component is blocked by the positive engagement.

[0017] Each drive unit preferably has at least one braking element. If the function of only one braking element is described below, this description is provided only as an example and representative of all drive units or braking elements of the emergency braking system.

[0018] If two drive units are provided on a work device, it is advantageously provided that the emergency braking system has two braking elements, i.e., one braking element on each drive unit. For example, it is also provided that each drive unit has at least two braking elements, which are designed and arranged for positive engagement with a component moving during operation of the work device. Alternatively, it is also provided that a drive unit has at least or exactly two braking elements, and that each of the two braking elements of a drive unit interacts positively with a different component to achieve a braking effect.

[0019] When the emergency braking system is triggered, the braking element, which was previously held at a distance from the moving component of the drive unit – in a release position, for example – is moved toward the moving component – ​​into a braking position – so that the braking element interacts positively with the moving component and stops or blocks the movement of the component. The moving component can be, for example, the drive wheel itself, a gear arranged between the drive wheel and the motor, a motor shaft of the motor, a brake body attached to the motor shaft of the motor, or another component that moves when the implement moves or contributes to the movement of the implement.Particularly preferably, the moving component is the rotor of an external rotor motor or a brake body attached to the motor shaft of the motor, which is blocked by the brake element when the emergency braking system is triggered. The brake body is arranged, for example, adjacent to the rotor.

[0020] The invention has the advantage over the prior art that the emergency braking system, provided in addition to the normal braking system or normal braking function, significantly shortens the braking distance in the event of an emergency stop being required to prevent damage to the surrounding area or the work equipment. The invention also has the advantage that the braking effect is generated by positive locking, not friction. This prevents wear of braking surfaces due to friction. Furthermore, the force required to move the braking element is reduced, since the braking effect is independent of the contact force. The blocking effect generated by the positive locking immediately stops all connected components, including the drive wheel, thus ensuring reliable emergency braking.

[0021] According to a first embodiment of the work device, the motor is provided with at least one motor shaft. At least one brake body is arranged on the motor shaft in such a way that it is connected to the motor shaft in a rotationally fixed manner. The brake body is designed, for example, as a brake ring. The brake body has a profile geometry, for example on an outer circumference. The profile geometry is designed such that it enables positive engagement with the brake element in order to block rotation of the brake body about the longitudinal axis of the motor shaft and thus also rotation of the motor shaft. The brake element is advantageously designed for positive engagement with the profile geometry. It is particularly advantageous that the profile geometry is arranged on an outer circumference of the brake body so that the brake element can be moved towards the brake body, in particular from the outside.The braking element thus interacts indirectly with the motor shaft via the brake body and blocks rotation of the motor shaft by blocking the brake body, which also blocks rotation of the drive wheel in the drive unit's chain of effects. It is also intended that the brake body be connected to the motor rotor to stop its rotation.

[0022] Preferably, the motor is designed as an external rotor motor. In particular, the motor shaft projects beyond a motor housing of the motor, so that the brake body is mounted on the protruding end of the motor shaft. The brake body is preferably made of a ductile and mechanically resilient plastic to prevent damage in the event of sudden impact of the brake element. In particular, the material of the brake element is selected to withstand the thermal stresses caused by the motor. For example, the brake body is made of polycarbonate (PC), polyamide (PA), or carbon-reinforced polypropylene (PP).

[0023] In particular, to advantageously ensure that the rotation of the brake body is blocked by the braking element, a further embodiment provides that the profile geometry has at least one catch cam. The catch cam is preferably arranged on an outer circumference of the brake body and protrudes radially from a circumferential surface. The brake body advantageously rotates together with the rotor of the motor about the longitudinal axis of the motor shaft. The radially outer circumferential surface of the brake body - starting from the longitudinal axis of the motor shaft - is the circumference on which the catch cam protrudes radially. The braking element is preferably moved translationally towards the brake body in the radial direction.The catch cam has, in particular, at least two side surfaces which—depending on the direction of rotation of the brake body—can interact positively with the brake element in such a way that rotation of the brake body is blocked by the brake element. The side surfaces are preferably oriented substantially transversely to the circumferential direction of the brake body.

[0024] Particularly preferably, the brake body has a plurality of catch cams on its circumference, for example, at least or exactly two, at least or exactly three, or at least or exactly four catch cams. The catch cams are preferably distributed evenly around the circumference of the brake body. Particularly preferably, three catch cams are provided.

[0025] If the braking element is moved towards the rotating braking body when the emergency braking system is triggered, the braking element either hits the catch cam or one of the catch cams or the circumferential surface of the braking body next to the catch cam or between the catch cams. If the braking body hits the catch cam on the front, it initially slides on the catch cam and then, after at least one further rotation of the catch cam, interacts in a form-fitting manner with at least one side surface of the catch cam to block the braking body. If the braking element hits the circumferential surface of the braking body next to the catch cam, the braking element initially slides along the circumferential surface until the catch cam has rotated towards the braking element and the form-fitting engagement occurring in the circumferential direction blocks the braking body.With an increased number of catch cams, the time until the brake body blocks is shortened, since if a catch cam is missed, it interacts with the next catch cam on the circumference.

[0026] For the force transmission between the braking element and the catch cam, it has proven particularly advantageous if, according to a further embodiment, at least one catch pocket is formed on at least one catch cam. It is preferably provided that at least two catch pockets are formed on at least one catch cam. The catch pockets are preferably arranged such that, depending on the direction of rotation of the braking body, the braking element interacts either with one catch pocket of a catch cam or with the other catch pocket of a catch cam. Preferably, a catch pocket is designed such that it has at least one undercut. An undercut is preferably designed as a recess oriented in the circumferential direction in a side surface of a catch cam.

[0027] For example, to form a catch pocket, at least one side surface of the catch cam forms an angle of less than 90° with an adjacent circumferential surface of the brake body. This can be achieved, for example, by having each side surface of a catch pocket lie in an imaginary plane that includes the longitudinal axis of the motor shaft, with the two side surfaces of a catch cam lying in different planes. For example, an angle of between 15° and 30° is formed between the two imaginary planes of two opposite side surfaces of a catch cam.

[0028] Preferably, at least one side surface of a catch cam and a circumferential surface of the brake body enclose an angle of between 45° and 75°. This steep angle of incidence of the side surface of a catch pocket ensures a more advantageous interaction between the braking element and the catch pocket and, in particular, forms an undercut acting in the radial direction. Consequently, the side surfaces of a catch cam are angled inwards, so that the catch cam, when viewed parallel to the longitudinal axis of the motor shaft, is wider at its distal end - in particular wider in the circumferential direction - than at its proximal end. In particular, each catch cam is symmetrical when viewed parallel to the longitudinal axis of the motor shaft, preferably mirror-symmetrical to an imaginary plane containing the longitudinal axis of the motor shaft.Preferably, each catch cam has a catch pocket in each of its side surfaces oriented transversely to the circumferential direction.

[0029] In order to advantageously ensure that a braking element in the braking position is advantageously guided into a catching pocket of a catching cam when the braking body rotates, a further embodiment of the working device provides for at least one feed bevel to be formed adjacent to each catching pocket in the circumferential direction. Adjacent to each catching pocket in the circumferential direction, the circumferential surface of the braking body is therefore not curved with a radius, but is formed as a surface, in particular as an inclined surface. In particular, each side surface of a catching cam encloses an angle of less than 90° with the associated feed bevel, in particular an angle between 45° and 75°. For example, an angle between 15° and 45° is formed between a tangent to an enveloping circle of the braking body at a point where the feed bevel begins and a feed bevel.

[0030] Preferably, each catch pocket has at least one feed slope, so that regardless of the direction of rotation of the motor shaft, there can always be an interaction between a braking element and a feed slope or a catch pocket.

[0031] According to a further embodiment of the implement, the braking element has at least one wedge-shaped section on the braking body, in particular for interacting with at least one catch pocket. The wedge-shaped section is preferably designed to correspond to the shape of a catch pocket, so that in particular the inner contour of a catch pocket essentially corresponds to the outer contour of the braking element - at least in the area interacting with the catch pocket. The catch pockets therefore represent a negative form of the braking element, at least in the area of ​​the wedge-shaped section. Upon rotation of the braking body, the wedge-shaped section can advantageously engage in a catch pocket of a catch cam in order to block the braking body from rotating.

[0032] Preferably, at least one second wedge-shaped section is provided on each brake element, so that in any direction of rotation of the brake body, the first wedge-shaped section or the second wedge-shaped section can always interact with one of the catch pockets of a catch cam.

[0033] In order to advantageously ensure simple insertion of the braking element into a catch pocket of a catch cam, a further embodiment of the implement provides that the braking element is arranged so as to be pivotable at least about an axis Z running substantially parallel to the motor shaft. The braking element is preferably moved translationally in a radial direction towards the braking body rotating about the longitudinal axis of the motor shaft. The braking element is held, for example on a plunger, in such a way that it can be pivoted or tilted about the axis Z. As a result, the braking element can advantageously bear against the circumferential surface of the braking body, depending on the direction of rotation of the motor shaft, in order to be inserted into a catch pocket, for example by means of a feed bevel. As soon as the braking element is inserted into the catch pocket, the braking body is abruptly stopped.Depending on the direction of rotation of the brake body, the braking element is tilted in one direction or the other. Guide means are preferably provided to limit the inclination of the braking element.

[0034] A further embodiment of the implement provides that the braking element has two inclined surfaces inclined in opposite directions to one another, and that the inclined surfaces are aligned for contact with the braking body. The two inclined surfaces inclined in opposite directions preferably form the contact surfaces of the braking element with the peripheral surface of the braking body. When the braking element is moved into its braking position on the braking body, depending on the direction of rotation of the braking body, either one or the other inclined surface advantageously rests against a feed slope of the braking body, so that the braking element is guided into a collecting pocket. The inclined surfaces of the braking element are preferably arranged in such a way that as soon as an inclined surface on the circumference of the braking body reaches the beginning of a feed slope, the braking body tilts in such a way that the inclined surface is guided along the feed slope.It has proven particularly advantageous if an angle of between approximately 100° and 130°, in particular 120°, is formed between the two inclined surfaces.

[0035] To ensure the interaction of each inclined surface with a feed slope, it has proven advantageous according to a further embodiment if at least one guide projection is formed between the two inclined surfaces, in particular at the contact line between the two inclined surfaces. For example, the guide projection has a semicircular cross-section, so that at the beginning of a feed slope, the braking element always tilts with its inclined surface in the direction of the feed slope.

[0036] For example, when viewed in a direction parallel to the longitudinal axis of the motor shaft, the brake element is designed to be mirror-symmetrical, at least in the area that interacts with the brake body. This ensures that the brake element can always interact with a catch cam, which is also advantageously designed to be mirror-symmetrical, regardless of the direction of rotation of the brake body.

[0037] Preferably, according to a further embodiment of the work device, the motor or each motor of each drive unit is designed as an external rotor with an external rotor. The rotor has a profile geometry, and the braking element is arranged and designed such that it can interact positively with the profile geometry to stop and block rotation of the braking body. After the emergency braking system is triggered, the braking element rests against the profile geometry of the rotor, whereby the external rotor of the motor is stopped by the braking element. Since the rotor of the motor is at least indirectly connected to the drive wheel, its movement is also stopped. For example, the profile geometry on the rotor is designed such that the rotor is directly connected to a described braking element.

[0038] According to a further embodiment of the work device, the drive unit has at least one gear, and the braking element is designed and arranged for positive engagement with at least one rotating component of the gear. For example, the braking element is designed for positive engagement with at least one rotating gear of the gear, in that the braking element engages with teeth of the gear to block the gear. Each drive unit preferably has at least one gear arranged between the motor and the drive wheel. The movement of the motor can be transmitted to the drive wheel via the gear. Each drive unit preferably has at least one braking element on the gear. If the gear is blocked, the drive wheel is also blocked at the same time, ensuring an emergency stop of the work device.

[0039] A further embodiment of the implement provides that the braking element is designed and arranged for positive engagement with at least one drive wheel. The braking element is designed, for example, to positively engage with a profile on the running surface of the drive wheel to block the rotation of the drive wheel. The braking element is preferably held in the drive unit so that it can be moved translationally or pivotally toward the drive wheel. It is also provided that the braking element is inserted parallel to the rotational axis of a drive wheel between spokes of the drive wheel to create a positive engagement and block the drive wheel.

[0040] For example, it is also provided that a drive unit has at least or exactly two brake elements, and that one of the two brake elements is arranged for positive engagement with a brake body on the motor shaft, while the other brake element is arranged for positive engagement with a rotating component of the transmission or with the drive wheel. Because two brake elements act simultaneously on moving parts of the drive unit in this development, the braking function can be enhanced.

[0041] In particular, to design the emergency braking system as a fail-safe system, a further embodiment of the work device provides that the drive unit has at least one clamping device. The clamping device is arranged and configured such that it exerts a force on the braking element, forcing the braking element into a braking position. Additionally, at least one release device is provided. The release device is configured to actively move the braking element into a release position against the force of the clamping device and, in particular, to hold it there.

[0042] This configuration has the advantage over the prior art in that the emergency braking system has a "fail-safe design." No actuator-induced movement of the braking element toward the component to be stopped, such as the brake body, the motor rotor, or a gearwheel of the transmission, is required; instead, the braking element is always forced toward the braking position. If, for example, the energy storage device of the implement no longer has enough voltage to actuate the release means, the braking element is automatically forced into its braking position by the clamping device, preventing movement of the implement. Therefore, the emergency braking system is preferably always triggered when the implement is switched off. The emergency braking system is consequently triggered when the release means no longer exerts a force counter to the force of the clamping device. The emergency braking system is released ordeactivated by - and in particular as long as - the release means creates a force that counteracts the force of the clamping means.

[0043] The clamping device is, for example, a spring, in particular a spiral, leg, or disc spring, which is arranged in such a way that it directly or indirectly exerts a force on the braking element in the direction of the braking position. Alternatively, the clamping device is designed as a pneumatic clamping system, in particular with at least one pressure chamber.

[0044] The release means is preferably designed as an electrical, hydraulic, or pneumatic actuator. During normal operation, the actuator holds the braking element in a release position against a force from the clamping device. As soon as the actuator is controlled in such a way that the release force is no longer applied or the release force is reduced, the clamping device automatically pushes the braking element into its braking position against the moving component. It is particularly preferred that the release means be designed as an electrical actuator. If, for example, the voltage of the battery of the work tool is no longer sufficient to apply a sufficiently large release force to the clamping device by means of the actuator, the emergency braking system is automatically triggered by moving the braking element towards the moving component. This ensures that the emergency braking system is always triggered even in the event of an unintentional voltage drop.

[0045] By creating a positive connection between the braking element and the component to be stopped, which creates a blocking effect, the force of the clamping device only needs to be sufficient to move the braking element into its braking position. The actual braking effect is independent of the force of the clamping device. This also allows the clamping device and thus also the release device to be smaller. Especially with electric actuators as the release device, this has a beneficial effect by reducing the heat output of an actuator coil and reducing energy consumption.

[0046] An exemplary embodiment provides that the actuator has at least one solenoid and at least one plunger. The plunger is held within the solenoid and can be moved translationally along its longitudinal axis by the solenoid. The braking element is coupled to the plunger and can be moved into a release position by means of a movement of the plunger within the solenoid. Preferably, the plunger is surrounded by a tensioning means designed as a spring, or a spring is arranged in the plunger. The spring urges the plunger out of the solenoid and thus always forces the braking element into a braking position, in particular against a braking body on the motor shaft.

[0047] When voltage is applied to the electric actuator, the plunger is moved into the cylinder coil, moving the braking element into its release position against the spring force. During normal operation of the implement, the braking element is actively held in its release position by the actuator. If a safety-relevant situation arises, the control device interrupts the power supply to the electric actuator, for example, causing the spring to push the braking element into its braking position and stopping the implement.

[0048] The electric actuator is preferably designed such that it can be operated directly with the voltage of the energy storage device of the work tool, in particular a battery. Because preferably only the force of the clamping device, in particular a spring, has to be overcome with the electric actuator, the actuator can also be operated with a low battery voltage of only approximately 10 volts, while at the same time ensuring reliable operation of the actuator. With a nominal voltage of approximately 14 volts, it is common for the actual voltage to fluctuate between approximately 11 volts and 17 volts. It must therefore be ensured that the actuator still generates sufficient release force at the lowest voltage and does not overheat at the highest voltage.Due to the low force required to be generated by the actuator, particularly because the clamping device is small and only a small force has to be applied by the release device, a DC-DC converter can be omitted, which further reduces both energy consumption and weight.

[0049] According to an alternative embodiment of the work device, the braking element can be moved into a braking position by an actuator. When the emergency braking system is triggered by the control device, the actuator causes the braking element to move toward the moving component of the drive unit to stop its movement. The actuator can be actuated electrically, hydraulically, or pneumatically, for example. For example, at least one compressed air chamber or compressed air cartridge is provided, which is used to move the braking element into the braking position.

[0050] According to a further embodiment, the braking element is preferably movable radially or tangentially in a translational manner toward the rotating component. Preferably, the braking element is movable substantially radially toward the outer rotor of the motor or the braking body in order to create the positive locking and to stop or block the component.

[0051] Alternatively, the braking element can be pivoted in the direction of the rotating component, for example, on a pivoting arm. Compared to the other embodiments, this embodiment requires more space for pivoting the arm.

[0052] In order for the emergency braking system to be triggered 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 trigger the emergency braking system 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, such as damage to the environment or the implement.

[0053] 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.

[0054] The control unit processes, for example, information from the environmental sensor system and, based on the exceedance of threshold values ​​and / or a profile of criteria for predefined situations, can identify a critical operating situation that requires the activation of the emergency braking system. For example, it is provided that the control unit is designed to initially initiate a normal braking process, for example using the motors of the drive units, after detecting a critical operating situation. After a predetermined period of time following the start of the braking process, a determination is made, for example based on movement data, e.g., current speed and direction of movement, and / or device data, e.g., shape of the housing, weight, position of the center of gravity, whether a damage event can be prevented by the braking process.If the control unit determines that a damage event cannot be prevented by braking, the emergency braking system is triggered.

[0055] For example, the environmental sensor system comprises at least one distance sensor, e.g., for determining a distance to a surface of the processing environment, and / or at least one optical environmental sensor. In particular, the environmental sensor is designed to monitor the distance of the implement in all directions, at least in one plane. If the control device detects, based on information from the environmental sensor system, that a predetermined, critical operating situation exists that requires emergency braking, or that a collision of the implement with an object or a fall of the implement is unavoidable without emergency braking, the control device triggers the emergency braking system.

[0056] A further embodiment of the work device provides that the control device is set up and configured to release the emergency braking system after an emergency braking operation. The control unit is set up to control the drive unit in such a way that a rotational movement of the blocked component is initially caused in a direction of rotation that is opposite to the direction of rotation before the emergency braking system is triggered. Particularly in embodiments in which the braking element is arranged in a retaining pocket on a retaining cam after the emergency braking, the braking element cannot easily be moved away from the braking body in the radial direction because the undercut blocks the movement. Therefore, a rotational movement of the braking body must first be carried out in a direction opposite to the original direction of rotation in order to release the braking element in the circumferential direction from engagement in the retaining pocket.The braking element can then be moved into the release position, for example using a release means.

[0057] The operational safety of the implement can preferably be increased according to a final embodiment by designing the emergency braking system such that it is triggered when the implement is switched off, i.e., the braking element is in a braking position or the braking elements are in a braking position. Furthermore, it is provided that the emergency braking system is released or deactivated after the implement is switched on or activated, namely, the braking element is moved to its release position. This occurs in particular if, after switching on, the control device, after an initial test using the environmental sensor system, does not detect any criteria requiring emergency braking.

[0058] The emergency braking system is particularly designed such that a force must always be exerted on the braking element(s) of the emergency braking system, which force holds the braking element(s) in a release position to enable movement of the implement. For this purpose, the emergency braking system preferably has - as described above - at least one tensioning means, e.g., in the form of a spring, for each braking element, which urges the braking element into its braking position even without a power supply. After the implement is switched on or activated, a release means, e.g., an electric actuator, ensures that the braking element is moved into its release position. In this way, the implement is braked safely without increasing the energy requirement.

[0059] In order to be able to effect a change in the direction of the implement during an emergency braking maneuver, a further embodiment of the implement provides that the control device is designed to selectively trigger the emergency braking system. The selective triggering of the emergency braking system comprises, for example, moving at least one or more selected braking elements. This embodiment is intended in particular for implements with at least two drive units, i.e., at least two braking elements.

[0060] If the control system detects that a damage event in a critical operating situation can also be advantageously prevented by an abrupt change in direction or rotation of the implement, the emergency braking system is only triggered selectively. For example, if two brake elements are present, only one is moved into its braking position. To do this, for example, the power supply to only one release device is interrupted, so that the tensioning device moves the respective brake element into a braking position. Because only one drive wheel is blocked when the emergency braking system is selectively triggered, in addition to the emergency braking, an abrupt change in direction or rotation of the implement also occurs, which can help prevent a damage event.

[0061] According to a non-claimed embodiment, a drive unit for a working device is described, in particular according to one of the above-described embodiments, wherein the drive unit is designed according to one of the described embodiments. The drive unit has, for example, at least one motor and at least one drive wheel and is characterized by the presence of at least one braking element, wherein the braking element is designed and arranged for positive engagement with a component of the drive unit that moves during operation of the working device. The drive unit preferably has at least one clamping means and one release means.

[0062] Further advantageous embodiments of the invention emerge from the following description of the figures and the dependent subclaims.

[0063] 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 side view, Fig. 3 shows the embodiment according to Fig. 2 in a perspective partial view, Fig. 4 shows a second embodiment of a drive unit for a working device, and Fig. 5 shows a third embodiment of a drive unit for a working device.

[0064] In the various figures of the drawing, identical parts are always provided with the same reference symbols.

[0065] 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.

[0066] Fig. 1 shows an exemplary 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.

[0067] Examples of embodiments of the drive units 3 for the working device 1 are shown in the Fig. 2 to Fig. 5 Each drive unit 3 comprises a motor 4, a gear 5, and a drive wheel 6. The motor 4 is designed as a brushless DC motor. The motor 4, the gear 5, and the drive wheel 6 are mounted on a common frame 3a. The gear 5 has a gear housing 5a.

[0068] The working device 1 according to Fig. 1 is designed and configured to move autonomously within a processing environment 7 and to perform work tasks, in this case cleaning the processing environment 7. In this exemplary embodiment, a working tool is a suction motor with a filter unit and a suction chamber for receiving suction material.

[0069] The work tool 1 has an environmental sensor system 8, which includes a plurality of sensors with which the environment of the work tool 1 can be monitored, at least at the level of the environmental sensor system 8. Monitoring the environment of the work tool 1 enables the control unit to automatically navigate the work tool 1 in the processing environment 7.

[0070] Fig. 2 shows a first embodiment of a drive unit 3, for example for a working device 1 according to Fig. 1 , in a side view. The working device 1 according to Fig. 1has an emergency braking system. As part of the emergency braking system, each drive unit 3 has a braking element 9. The emergency braking system can be controlled by the control device, i.e., triggered and released. The triggering of the emergency braking system results in the braking element 9 or all braking elements 9 of the implement 1 interacting positively with a component 10 moving during operation of the implement 1 in order to stop any movement of the implement 1 as quickly as possible (see Fig. 2 to 5 ).

[0071] Fig. 3 shows the embodiment according to Fig.2 in a perspective detailed view. According to Fig. 2 and Fig. 3A drive wheel 6 is rotatably mounted in the frame 3a of the drive unit 3. The drive wheel 6 is driven by a motor 4 via a gear 5, on whose motor shaft 16 a brake body 10b is moved as the component 10 to be braked or stopped. The brake body 10b is connected to the motor shaft 16 in such a way that stopping the rotation of the brake body 10b also blocks the motor shaft 16, namely, preventing it from rotating. The brake body 10b is designed here as a brake ring.

[0072] The brake body 10b is preferably arranged such that it is adjacent to the rotor of the motor 4 in the axial direction on the motor shaft 16. The brake body 10b rotates during operation of the implement 1 at the same speed as the motor shaft 16. A brake element 9 is arranged on the frame 3a, which according to Fig. 2 and 3is shown in its release position. With the braking element 9, a movement of the braking body 10b and thus a movement of the motor shaft 16 can be blocked in a braking position of the braking element 9. For this purpose, the braking element 9 is moved towards a circumferential surface 17 of the braking body 10b. The profile geometry 15 of the braking body 10b is designed for positive engagement with the braking element 9. In this exemplary embodiment, the profile geometry 15 of the braking body 10b has three catch cams 18, each of which is designed for positive engagement with the braking element 9 to block the rotation of the braking body 10b.

[0073] Depending on the current orientation of the rotating brake body 10b, the brake element 9, when moving into its braking position, either strikes one of the three catch cams 18 on its front side or the circumferential surface 17 between the catch cams 18. The catch cams 18 are evenly distributed over the circumference of the brake body 10b and protrude from the circumferential surface 17. The protrusion is not related to an imaginary envelope curve, but to the actual circumferential surface 17 of the brake body 10b.

[0074] The side surfaces 19 of the catch cams 18, which are oriented transversely to the circumferential direction, are arranged relative to the circumferential surface 17 of the brake body 10b such that they form an angle of less than 90° with the circumferential surface 17, so that a catch pocket 20 is formed between the circumferential surface 17 and a side surface 19 of a catch cam 18 by the resulting undercut. In the event of an emergency braking operation, a catch pocket 20 interacts in a positive-locking manner with a wedge-shaped first section 9a or with a wedge-shaped second section 9b of the brake element 9, depending on the direction of rotation of the brake body 10b.

[0075] Advantageously, the outer contour of the first section 9a and the second section 9b of the braking element 9 substantially corresponds to the inner contour of a catch pocket 20. The braking element 9 is tiltable about an axis Z arranged parallel to the longitudinal axis of the motor shaft 16, so that the braking element 9, as soon as it is forced into its braking position, can interact with feed slopes 21 formed circumferentially adjacent to each catch pocket 20. The feed slopes 21 are inclined such that they guide the braking element 9 into the associated catch pocket 20.

[0076] For advantageous interaction with the feed slopes 21, the braking element 9 has two mutually inclined inclined surfaces 9c and 9d, which in this embodiment are inclined at an angle of approximately 120° to one another. In the braking position, depending on the direction of rotation of the braking body 10b, either the first inclined surface 9c or the second inclined surface 9d interacts with a feed slope 21. To ensure reliable insertion into a catch pocket 20 by tilting the braking element 9, a guide projection 22 is provided between the inclined surfaces 9c, 9d, which in this embodiment has an approximately semicircular cross-section. The guide projection 22 ensures that the respective inclined surface 9c, 9d tilts onto a feed slope 21, in particular when the guide projection 22 reaches the beginning of the feed slope 21.

[0077] The brake element 9 is held on a plunger 14. Within the plunger 14 is a Fig. 2 and Fig. 3 A tensioning device 11 (not shown) in the form of a spring is held, which moves the plunger out of the release device 12—here in the form of an electric actuator—and thus urges the braking element 9 into its braking position. For this purpose, the braking element 9, together with the plunger 14 and the release device 12, is held on the frame 3a of the drive unit 3. With the release device 12, the braking element 9 can be moved into a release position against the force of the tensioning device 11. The release device 12 has at least one solenoid coil in which the plunger 14 is guided.

[0078] If the release means 12 is actuated by the control device, for example, after switching on the work tool 1 and for the duration of normal operation, the plunger 14 is moved translationally along its longitudinal axis by the solenoid, so that the braking element 9 also moves and enables rotation of the braking body 10b. If the emergency braking system is triggered, for example, the voltage supply to the release means 12 is interrupted, and the force of the clamping means 11 causes the braking element 9 to move into the braking position and thus engage positively with a catch cam 18 of the braking body 10b.

[0079] The drive units 3 of the Fig. 4 and 5 are essentially identical to the drive unit 3 described above according to Fig. 2 and Fig. 3 built so that for the Fig. 4 and Fig. 5Reference is made to the above description. The only difference between the exemplary embodiments is the spatial assignment of the braking element 9 to different components 10 with which the braking element 9 of the emergency braking system interacts in a form-fitting manner.

[0080] In all embodiments of the Fig. 2 to Fig. 5 The braking element 9 is always forced into its braking position, so that a braking effect is always achieved when the release means 12 is not activated. The release means 12 is designed in the form of an electrically operated actuator that moves the braking element 9 into its release position when activated.

[0081] According to the embodiment of the Fig. 4The braking element 9 is designed for positive engagement with a profile in the running surface 10a of the drive wheel 6 in order to stop the movement of the implement 1. For this purpose, the braking element 9, together with the clamping means 11 and the release means 12, is held on the frame 3a of the drive unit 3. Furthermore, a release means 12 in the form of an electrically actuated actuator is provided, with which the braking element 9 can be moved into a release position against the force of the clamping means 11. The release means 12 has at least one solenoid coil in which a plunger 14 is guided, on which the braking element 9 is held. If the release means 12 is actuated by the control device, for example, after the implement 1 is switched on and for the duration of normal operation, the plunger 14 is moved translationally along its longitudinal axis by the solenoid coil, so that the braking element 9 also moves and releases rotation of the drive wheel 6.

[0082] In the embodiment of the Fig. 5 The braking element 9 is arranged for positive engagement with the teeth of a gear in the transmission 5 in order to stop the movement of the working device 1. For this purpose, the braking element 9 is arranged together with the clamping means 11 and the release means 12 on the housing 5a of the transmission 5.

[0083] The drive units 3 of the embodiments of the Fig. 2 to Fig. 5 are movable in a vertical direction, i.e. downwards during operation, in a housing 2 of a working device 1 according to Fig. 1 A plug socket 13 is provided to supply power to the motor 4 and the release device 12.

[0084] The invention is not limited to the illustrated and described embodiments, but also encompasses all equivalent embodiments within the meaning of the invention. The scope of the invention is defined by the subject matter of the claims. List of reference symbols

[0085] 1Working device 2Housing 3Drive unit 3aFrame of 3 4Motor 5Gearbox 5aHousing of 5 6Drive wheel 7Machining environment 8Environmental sensor system 9Braking element 9aFirst section 9bSecond section 9cFirst inclined surface 9dSecond inclined surface 10Moving component 10aRunning surface 10bBrake body 11Clamping device 12Releasing device 13Plug socket 14Plunger piston 15Profile geometry 16Motor shaft 17Circumferential surface 18Catch cam 19Side surfaces 20Catch pocket 21Feed bevel 22Guide projection Z-axis

Claims

1. Working device (1), having at least one housing (2), at least one drive unit (3) and at least one control device, the drive unit (3) having at least one motor (4) and at least one drive wheel (6), the working device (1) being designed and set up to move autonomously in a processing environment (7), an emergency braking system having at least one braking element (9) being present, and the emergency braking system being controllable by the control device, characterized in that the braking element (9) interacts positively with at least one component (10) of the drive unit (3) moving during operation of the working device (1) after the emergency braking system has been triggered in order to achieve a braking effect.

2. Working device (1) according to claim 1, characterized in that the motor (4) has at least one motor shaft (16), that at least one brake body (10b) is arranged on the motor shaft (16), that the brake body (10b) has a profile geometry (15), in particular a profile geometry (15) formed on an outer circumference, and that the brake element (9) is designed to interact positively with the profile geometry (15).

3. Working device (1) according to claim 2, characterized in that the profile geometry (15) has at least one catch cam (18) or a plurality of catch cams (18), in particular on an outer circumference of the brake body (10b).

4. Working device (1) according to claim 3, characterized in that at least one catch pocket (20) is formed on at least one catch cam (18), in particular in that the catch pocket (20) has at least one undercut, preferably in that at least one side surface (19) of the catch cam (18) forms an angle of less than 90°, in particular between approximately 45° and 75°, with a circumferential surface (17) of the brake body (19b) in order to form a catch pocket (20).

5. Working device (1) according to claim 4, characterized in that at least one feed slope (21) is formed adjacent to each catch pocket (20) in the circumferential direction.

6. Working device (1) according to any one of claims 1 to 5, characterized in that the braking element (9) has at least one first wedge-shaped section (9a) for interacting with at least one catch pocket (20) on the brake body (10b), preferably in that the braking element (10b) has at least one second wedge-shaped section (9b).

7. Working device (1) according to any one of claims 1 to 6, characterized in that the brake element (10b) is arranged so as to be pivotable at least about an axis (Z) running essentially parallel to the motor shaft (16).

8. Working device (1) according to any one of claims 1 to 7, characterized in that the braking element (9) has two inclined surfaces (9c, 9d) inclined in opposite directions to one another, and in that the inclined surfaces (9c, 9d) are aligned for contacting the brake body (10b), in particular in that the inclined surfaces (9c, 9d) are inclined at an angle of between 100° and 130° to one another.

9. Working device (1) according to claim 8, characterized in that at least one guide projection (22) is formed between the two inclined surfaces (9c, 9d), in particular a guide projection (22) with a semicircular cross-section is formed.

10. Working device (1) according to any one of claims 1 to 9, characterized in that the motor (4) is designed as an external rotor with an external rotor, in that the rotor has a profile geometry (15) and in that the brake element (9) is designed to interact positively with the external rotor and / or in that the drive unit (3) has at least one gearbox (5), and in that the brake element (9) is designed to interact positively with at least one rotating component of the gearbox (5) and / or in that the brake element (9) is designed to interact positively with at least one drive wheel (6).

11. Working device (1) according to any one of claims 1 to 10, characterized in that at least one clamping means (11) is provided, in that the clamping means (11) can be used to exert a force on the braking element (9) which urges the braking element (9) into a braking position, in that at least one release means (12) is provided, and in that the release means (12) is designed to move the braking element (9) into a release position counter to the force of the clamping means (11).

12. Working device (1) according to any one of claims 1 to 11, characterized in that the braking element (9) can be moved into a braking position by an actuator, and that the actuator can be actuated electrically, hydraulically or pneumatically.

13. Working device (1) according to any one of claims 1 to 12, characterized in that the control device is set up and designed to effect a release of the emergency braking system after an emergency braking operation by controlling the drive unit (3) in such a way that it first causes a rotary movement of the blocked component (10) in a direction of rotation which is opposite to the direction of rotation of the component (10) before the emergency braking system is triggered, in order to then move the braking element (9) with the release means (12) into its release position.

14. Working device (1) according to any one of claims 1 to 13, characterized in that the emergency braking system is designed and set up in such a way that the emergency braking system is triggered when the working device (1) is switched off, and that the emergency braking system is released after the working device (1) is switched on.