Service robot tires, especially lawnmower robot tires

Abstract

The invention relates to a tire (10) for a service robot (100), in particular a lawnmower robot tire (12), having a plurality of studs (22) distributed over the circumference of the tire (10). It is proposed that in the axial direction (38) of the tire (10) the studs (22) are arranged in four rows (80a, 80b, 80c, 80d) of studs (22) distributed over the circumference, wherein the studs (22a, 22b, 22c, 22d) of each row (80a, 80b, 80c, 80d) are arranged offset in the axial direction (38) and / or in the circumferential direction (48) with respect to studs (22a, 22b, 22c, 22d) of the other rows (80a, 80b, 80c, 80d), in particular are arranged spaced apart without overlap and / or offset.

Description

State of the art

[0001] Tires for service robots, preferably drive tires, in particular lawnmower robot tires, having a plurality of studs distributed over the circumference of the tire, with the features of the preamble of claim 1 are already known. Reference is made, for example, to document EP 2 657 043 A1. Disclosure of the invention

[0002] The invention relates to a tire for a service robot, in particular a lawnmower robot tire, having the features of independent claim 1. Advantageous further developments emerge from the dependent claims.

[0003] Such a tire can improve the grip or traction of the tire on the ground, especially on grass. Damage to the ground can be avoided. For example, damage caused by bending blades of grass or spinning on blades of grass or the like. Excessive penetration into the ground can be avoided. Lateral grip of the tire can be improved, especially between blades of grass or to prevent sideways slipping. For example, a service robot equipped with the tire, preferably an autonomous lawnmower, can drive more accurately when driving sideways on a slope. Excessive deformation of a lug can also be avoided, which would sometimes vary traction. Lane keeping quality can thus be improved. Sideways drift can be avoided.The localization accuracy of the service robot can be improved, in particular by avoiding slippage or drift on one of the drive wheels, which would otherwise have a negative impact on the odometry measurement used to localize the service robot. The maneuverability of the service robot can be increased. Overall, the reliability of operating a service robot with the tire can be improved. Industrialized tire production can also be enabled. Clogging of the tire surface, particularly between the lugs, for example with grass, dirt, mud, or the like, can be avoided. The self-cleaning effect of the tire can be improved.

[0004] A "service robot" is to be understood in particular as an at least partially automatic mobile device that performs a task, preferably the processing of a surface - in particular a so-called processing surface, at least partially independently. In particular, the service robot or robot is to independently start a task, independently finish it, and / or independently select and / or influence at least one parameter relating to the processing of the processing surface. A service robot is to be understood in particular as a device that moves independently at least to perform this task, in particular to process the processing surface, and / or moves autonomously within the specified working area of ​​the processing surface. Typical areas of application for such robots include a wide variety of activities such as sweeping, cleaning, mowing the lawn, collecting, sorting, watering, fertilizing, mapping, or the like.Examples of this include, in particular, autonomous cleaning robots, autonomous snow removal robots, autonomous sowing machines, autonomous irrigation robots, autonomous fertilizing machines, autonomous mapping machines, or the like, and very particularly preferably autonomous lawnmowers or robotic lawnmowers. In particular, robotic lawnmowers whose effective range extends to the surroundings of a residential building, in particular the garden of a residential building. With drive tires, or with drive wheels comprising drive tires, service robots can move or maneuver in an environment - typically by driving drive tires or drive wheels independently of one another, thus enabling the service robot to change direction. Service robots typically have sensors, a control and / or regulating unit, and a drive unit. A "control and / or regulating unit" is to be understood in particular as a unit with at least one control electronics system.The term “control electronics” is to be understood in particular as a unit comprising a processor unit and a memory unit as well as an operating program stored in the memory unit.

[0005] A tire for a service robot, in particular a lawnmower robot tire, is proposed, comprising a plurality of lugs distributed over the circumference of the tire, wherein a lug has a root portion that is based on a casing or base circle surface of the tire and a head portion that has a radial end or tread of the lug. In particular, the head portion supports or forms an end or tread of the lug or tire. The radial end or tread can be flat or curved. It is proposed that a lateral surface of the root portion of the lug, with respect to a radial axis of the lug, has an orientation that essentially spreads out from the casing or base circle surface.It is proposed that a side surface of the head part of the lug, relative to the radial axis of the lug, has a side surface that essentially does not spread out, preferably one that runs essentially parallel to the radial axis. The radial axis of the lug is a radial axis of the tire that intersects the lug. It runs essentially perpendicular to the tire's axis of rotation. Each lug extends in the direction of its radial axis and projects radially outwards from the tire's casing or base circle surface. A lug has a height that extends in the direction of the radial axis. The height of the lug is measured in particular at least from the height of the foot part and the height of the head part, and sometimes the height of the front or tread surface. The foot part preferably does not consist solely of a rounded transition area to the tire's casing or base circle surface.The head part preferably does not consist solely of a rounded transition area to the front or tread of the lug. A height of the foot part is preferably greater than a height of the head part. A side surface of the foot part of the lug has a different orientation than a side surface of the head part of the lug, in particular with respect to the radial axis of the lug. In particular, the orientations of the side surfaces of the foot and / or head part are straight. In particular, the side surfaces of the foot and foot part each extend substantially in one side surface plane. In particular, side surfaces of the foot and head parts of the lug each point in the circumferential direction of the tire, in particular in opposite circumferential surfaces of the tire - so to speak in the forward and rearward direction of the tire, in particular aligned at least parallel to the tire's axis of rotation.

[0006] Preferably, a side surface of the foot part spreads in the radial axis direction of the lug towards the rotational axis of the tire. A side surface of the head part, in contrast, runs essentially without spreading in the radial axis direction of the lug. In particular, the side surface of the head part runs essentially parallel to the radial axis, while the side surface of the foot part opens at an angle, in particular an acute angle, in particular an acute angle opening towards the rotational axis of the tire. In principle, however, a parabolic or hyperbolic course of the side surface of the foot part spreading towards the surface of the tire's casing or base circle is also conceivable. However, this should not correspond to a pure transition radius from the foot part to the surface of the casing or base circle.

[0007] Preferably, the adjacent or contiguous side surfaces of the foot part and head part in the radial axis direction have different orientations. Orientation refers to the surface contour of the side surface when viewed in the direction of the radial axis of the lug or a radial axis of the tire that intersects the lug. A radial axis of the lug advantageously intersects the tire's rotational axis essentially perpendicularly. It intersects the lug essentially centrally. It is essentially aligned normal to the front or tread surface of the lug.The expression “substantially perpendicular” is intended here to define in particular an orientation of a direction relative to a reference direction, wherein the direction and the reference direction, in particular viewed in a plane, enclose an angle of 90° and the angle has a maximum deviation of in particular less than 8°, advantageously less than 5° and particularly advantageously less than 2°.

[0008] The radial axis of the lug runs essentially in the radial direction of the tire and / or perpendicular to the front or tread of the lug. Each lug has a radial axis and is intersected centrally by this radial axis, which is essentially perpendicular to the tire's rotational axis. The height of the lug is measured in the direction of the radial axis. In principle, an intermediate part or segment with a different orientation, cross-sectional shape, and / or basic shape could also be provided between the base and head sections.

[0009] The different alignment of the foot and head sections, in particular the radial axis-parallel course of the side surface of the foot section and in particular the spreading course of the side surface of the foot section, can improve the traction of the tire on the ground, especially in the area of ​​the head section - in particular without damaging the ground. The head section can advantageously sink between blades of grass without bending them. Driving or holding forces close to the roots can be transferred to the ground and / or to the blade of grass, which is relatively resistant to bending or kink near the roots. By aligning the side surfaces, for example essentially parallel to the radial axis of the tire or stud, sufficient sinking of the tire or stud, for example down to the turf and / or sinking close to the roots can be achieved.The different orientation of the base section, particularly the shape that expands toward the rotation axis, prevents the stud from sinking deeper into the subsoil, especially into the turf of a lawn. Furthermore, the base section's expanding side surface, particularly in the circumferential direction, deflects grass blades without kinking or at least with minimal kinking.

[0010] The stability of the stud can be increased, in particular by the expanding base section. The tendency of the stud to bend can be reduced. The surface pressure of a stud on the subgrade in the sinking area of ​​the stud head is essentially constant over the sinking depth of the head section. It decreases increasingly in the sinking area of ​​the stud foot with increasing sinking depth. In particular, the surface pressure of the stud decreases increasingly as the penetration depth of the stud into the subgrade exceeds the head section - namely due to the additional contact surface provided by the base section or, in particular, the side surfaces of the base section, or the increasing cross-sectional area of ​​the stud.The alignment of the lateral surfaces of the base part of the stud can also create a lifting effect, particularly by exerting a driving torque from the tire to the ground – particularly through a lateral surface that is angled, oblique, and / or curved relative to the radial axis. This allows, for example, a stud or tire that has penetrated too deeply into the turf to be pushed out by driving forces into a position where the base part no longer penetrates – particularly through the resulting lifting effect of the lateral surface spreading toward the base circle or lateral surface.

[0011] It is proposed that at least one lug, in particular a plurality of lugs, preferably all lugs of a tire, have at least a root and a head part. The root part of a lug is based on a casing or base circle surface of the tire. The respective head part of a lug is arranged radially on or mounted on the root part, in particular is formed integrally with it. “Integral” should be understood in particular to mean at least materially connected and / or advantageously formed in one piece. Production takes place, for example, using a single-component or multi-component injection molding process. The material of the tire is in particular rubber-like or contains rubber. In particular, the tire material is TPU. The head part of the lug has a radial end face or carries or forms this; or forms at least part of a tread of the tire.In particular, the lugs are designed such that they protrude radially from a base or lateral surface of the tire, i.e., preferably outward in the radial direction. Each lug has a radial axis that runs essentially perpendicular to the tire's axis of rotation and penetrates the center of the respective lug.

[0012] It is proposed that a side surface of the foot part is oriented substantially at an angle or obliquely, parabolically and / or hyperbolically to a radial axis of the stud and that a side surface of the head part is oriented substantially parallel to the radial axis of the stud, in particular side surfaces of the foot or head part pointing in the circumferential direction of the tire. In particular, a side surface of the foot or head part spanned in the axial direction of the tire and at an angle or parallel to the radial axis of the stud. By "substantially angular" is meant in particular an orientation of a direction relative to a reference direction, in particular in a plane, wherein the direction comprises an angle with respect to the reference direction which can no longer be considered substantially parallel.By “substantially parallel” is meant in particular an alignment of a direction relative to a reference direction, in particular in a plane, wherein the direction has a deviation from the reference direction of in particular less than 8°, advantageously less than 5° and particularly advantageously less than 3°. Such a deviation can sometimes be necessary in order to enable easy demolding of the tire or the stud from the tool, particularly in industrial production. In particular, side surfaces of the head part, or in the head region of the stud, can be chamfered by 2° to enable good demolding. Parabolic or hyperbolic shape is meant that the side surface has a curvature or bend relative to the radial axis of the stud, or is curved around a fictitious axis parallel to the axis of rotation of the tire.

[0013] It is proposed that the side surface of the base part be aligned at an acute angle to the radial axis of the stud, in particular having an angle of 5-45°, preferably of 10-20°, particularly preferably of around 15°, in particular wherein the angle tapers radially outwards at an acute angle. In particular, opposite side surfaces of the base part of the stud in the circumferential direction are formed at an angle, in particular at an acute angle, to one another. Opposite side surfaces of the base part are preferably aligned at an isosceles angle to one another, in particular at an isosceles acute angle to one another with respect to the radial axis. However, it is conceivable that, for example, only one side surface of the stud, in particular a side surface in contact with the ground and facing the main direction of travel, is formed at an acute angle to the radial axis of the stud.The opposite side surface of the lug could then, for example, be designed essentially parallel to the radial axis of the lug. This could, for example, alter the sinking behavior and / or achieve a different traction or propulsion behavior. Due to the angled design of the side surfaces of the base part of the lug on both sides, especially the side surfaces facing in the circumferential direction, the tire is equally suitable for forward and reverse driving, and can thus unfold its advantages.

[0014] It is proposed that circumferentially opposite side surfaces of the base part of the lug be aligned at an angle, preferably at an acute angle, in particular isosceles, to one another. In particular, the lug has, in an axial sectional plane perpendicular to the tire's axis of rotation, a substantially isosceles trapezoidal base part sectional surface and a substantially rectangular or square head part sectional surface. This geometric shape can optimize the sinking behavior. The sides of the trapezoidal base part sectional surface in the axial sectional plane advantageously form an angle of 90° with the base side, less the aforementioned angle of 5-45°, preferably 10-20°, particularly preferably 15°. The angle of the trapezoidal sides of the lug base to the radial axis or radial axis plane is preferably 15° in each case, and the angle of the trapezoidal sides to one another is 30°.In this context, "essential" should be understood to mean, in particular, that a deviation from a specified geometry is less than 20%, preferably less than 10%, and especially less than 5%. Clogging of the spaces between the studs with dirt can be prevented. The stud's sinking behavior, particularly in grass, can be optimized. The stud's stability can be improved.As before, for the substantially rectangular or square head part sectional surface in the axial sectional plane, the limbs of the substantially rectangular or square head part sectional surface running in the radial axial direction run substantially parallel to one another, i.e., in particular, they have an orientation of a direction relative to a reference direction, in particular in a plane, wherein the direction has a deviation from the reference direction of, in particular, less than 8°, advantageously less than 5°, and particularly advantageously less than 3°. The end face or running surface can also be concavely or convexly curved, in particular concavely or convexly curved in the radial axial direction.

[0015] Clogging of the spaces between the lugs with dirt can be prevented. A certain degree of sinking of the lug, particularly into the subsoil, can be enabled. Surface pressure can be reduced depending on the depth of sinking into the ground. The stability of the lug can be improved, particularly in the drive direction. The angle of the side surface of the root section, which is formed at an acute angle to the radial axis or radial axis plane, can in particular be 15°. In principle, other acute angles of in particular 5-45° are also conceivable. Opposite side surfaces of the root section of the tire can, for example, each enclose an angle of 15° to the radial axis, or the side surfaces of a lug can enclose an angle of 30° to each other. The side surface of the root section, in particular the opposite side surfaces of the root section, taper at an acute angle, particularly starting from the casing or base circle surface of the tire, to the head part of the lug.The above includes the fact that the base part of the stud can, in principle, also be truncated cone-shaped or truncated pyramid-shaped. The head part could, in principle, also be cylindrical. Other base and head part shapes would also be conceivable in principle. By "substantially parallel" is meant here in particular an alignment of a direction relative to a reference direction, in particular in a plane, wherein the direction has a deviation from the reference direction of in particular less than 5° and preferably less than 2°.

[0016] Such angular deviations can be provided here, for example, to simplify or enable demoulding of the tyre from the tool during production.

[0017] It is proposed that the basic shape of the lug be substantially quadrangular around the radial axis. In particular, the sides of the quadrilateral are aligned parallel and perpendicular to the tire's rotational axis. The basic shape of the head portion is substantially cuboidal, and the basic shape of the foot portion is substantially trapezoidal-prism-shaped and / or truncated pyramid-shaped.

[0018] It is proposed that the stud has, in an axial section plane perpendicular to the axis of rotation of the tire, a substantially isosceles trapezoidal root section surface and a substantially rectangular or square head section surface.

[0019] It is proposed that the base part of the stud is essentially trapezoidal prism-shaped or truncated pyramid-shaped and the head part is essentially cuboid-shaped or cube-shaped, or that the base part is essentially truncated cone-shaped and the head part is essentially cylindrical.

[0020] It is proposed that the stud has a substantially rectangular cross-sectional area shape in the region of the foot part and a substantially square cross-sectional area shape in the region of the head part in radial section planes perpendicular to the radial axis of the stud, preferably wherein the longer side of the rectangular cross-sectional area shape of the foot part is aligned in the circumferential direction of the tire.

[0021] The base and head sections each have a height. Together, they define the height of the stud. It is proposed that the height of the base section in the radial axis direction be greater than the height of the head section, in particular between 1 and 2.5 times greater, preferably 1.5 to 2 times greater. For example, the height of the head section can be 2.4 mm and the height of the base section can be 3.6 to 4.6 mm. Damage to blades of grass and / or the turf can be avoided. The sinking behavior of the stud, particularly in grass, can be improved. The stability of the stud can be improved.

[0022] It is proposed that at least one transition region from the casing or base circle surface of the tire to the lug, in particular to at least one side surface of the lug, in particular to at least one side surface of the foot part of the lug and / or a transition region from the foot part to the head part of the lug, in particular a side surface of the foot part to a side surface of the head part of the lug, and / or a transition region from the head part to the end face of the lug, in particular from at least one side surface of the head part of the lug to the end face of the lug, is rounded, in particular concavely or convexly rounded, in particular having a radius of curvature of 0.25 to 2 mm, preferably of 0.5 mm or 1.5 mm.It is proposed that the transition region between adjacent side surfaces of the lug in the circumferential direction around the radial axis is not rounded at least on one side, in particular in the transition region to the side of the lug facing the axial center of the tire, preferably both on the head and foot sections. Damage to the turf can be avoided. Sinking behavior of the lug, particularly in grass, can be optimized. Stability of the lug can be improved. Straight-line driving can be improved. In some cases, this makes it easy to create four rows of lugs distributed over the circumference.

[0023] It is further proposed that a radial end face or tread of the stud(s) is substantially square and / or a root face of the stud(s) is substantially rectangular, in particular a root face of the stud(s) at which the stud(s) rest(s) on the lateral surface or root circle surface of the tire. The longitudinal side of the rectangular surface with the greater extent extends in particular in the circumferential direction. The radial end face can also be substantially square, for example, because rounded portions are provided between the side surfaces of the head part and the radial end face. In particular, rounded portions are not provided on all sides of the substantially square head part.

[0024] Furthermore, a tire for a service robot is assumed, in particular a lawnmower robot tire, having a plurality of studs distributed over the circumference of the tire. It is proposed that the studs be arranged in four rows of studs distributed over the circumference in the axial direction of the tire, wherein the studs in each row are offset from the studs in the other rows in the axial direction and / or in the circumferential direction, in particular offset and / or spaced apart in the axial direction and / or in the circumferential direction without overlap. That is to say, they are arranged offset from the studs in the axially immediately adjacent rows and those not axially immediately adjacent rows. In this way, it can be avoided that, for example, a blade of grass can be bent over and / or damaged by studs in one row that are adjacent in the circumferential direction and / or that a blade of grass can be damaged by studs in two axially adjacent rows. Slipping of the stud on blades of grass can be prevented.This prevents the grass blades from being torn out, and damage to the lawn is also avoided. In particular, all studs in a row are constructed identically.

[0025] It is proposed that the lugs are arranged sequentially in axial projection, i.e. in projection along the axis of rotation of the tire and viewed in the circumferential direction of the tire, such that a lug in the axially first row follows a lug in the axially second row, then a lug in the axially fourth row, and finally a lug in the axially third row. The axially first row preferably borders on an outer side of the tire, and the axially fourth row preferably borders on an inner side. This arrangement can advantageously prevent lateral drift when the tire rolls. The quality of directional control can be increased. In particular, the quality of straight-line driving and cornering is improved. This has particular advantages over an arrangement according to which a lug in the axially first row follows a lug in the axially second row, then the third and finally the fourth row, or vice versa.In contrast, transverse forces acting on the ground, especially blades of grass or the turf, can be avoided when driving straight ahead and / or around curves.

[0026] It is proposed that an axial offset of axially adjacent rows is unequal. In particular, an axial offset of the two middle rows to one another, in particular the second and third row to one another, is less than an offset of the first to the second and / or the third to the fourth row. In particular, an axial offset of the first to the second and / or the third to the fourth row is greater by a factor of 0.5 - 1.5, preferably by a factor of 0.75 - 1.25, than an axial offset of the two middle rows to one another. In particular, an axial offset of the first to the second row is around 4.5 mm. An offset of the third to the fourth row can be around 3.5 mm. And an offset of the two middle rows, i.e. the second to the third row, can preferably be around 2 mm. This can also improve the directional stability.

[0027] It is proposed that circumferentially adjacent lugs of each of the four rows be arranged at an angular distance of 24° from one another and / or that the lugs of all rows, viewed in the axial projection and circumferential direction of the tire, be arranged at an angular distance of 6° from one another, in particular with the lugs of the first row being arranged at an angular distance of 6° from one another and with the lugs of the third row being arranged at an angular distance of 12° from one another. Each of the four rows can therefore have 15 lugs, each arranged at an angular distance of 24° from one another. The tire or all rows of lugs together can have 60 lugs. This means that a plurality of lugs can contact the ground on both hard and soft surfaces, in particular on hard / firm surfaces such as stone soil and very soft surfaces such as long grass.For example, on rocky ground, approximately three lugs touch the ground simultaneously, and on long grass, approximately eight lugs touch the ground simultaneously. This allows the tire to be used with minimal damage on a variety of surfaces, especially on different types of dry, wet, short, and long grass.

[0028] It is proposed that an axial width of the tire be 50-75% larger, in particular 65-70%, in particular around 2 / 3 larger than an accumulated axial width of four head or end faces of each lug in the four rows and / or that an axial width of the tire be a factor of 5-8, preferably 6-7 times larger than an axial width of a radial head or end face of a lug. The term width here refers to a width in the axial direction or rotational axis direction of the tire. In particular, an axial width of the tire is around 30 mm and an accumulated axial width of the radial head or end faces of each lug in the four rows is around 18-20 mm. In particular, an axial width of an end face of a lug is 4.5-5 mm. In principle, other width factor differences or width dimensions are also conceivable. However, it has been shown that a factor of 6-7 is particularly advantageous with regard to the aforementioned advantages.This improves the sinking behavior of the lug(s) or tire, particularly in grass. The surface pressure exerted on the grass surface can be reduced. Damage, particularly to the turf, can be avoided. Tire traction can be improved. The sinking behavior of the lug between grass blades can be improved without bending the blade of grass or causing it to spin. Support for the forces resulting from the drive torque can be transferred to the grass or turf and / or the blade of grass close to the roots.

[0029] It is proposed that a height of a lug, in particular starting from a base or lateral surface of the tire up to the radial head or end face of a lug, be greater than a length of a radial end face of the lug in the circumferential direction of the tire, in particular 1.5-2 times greater, and / or that a height of a head part of a lug is smaller than a length of a radial end face of the lug in the circumferential direction, and / or that a height of a foot part of a lug is approximately the same as a length of a radial end face of the lug in the circumferential direction. The aforementioned advantages can also be achieved in this way.

[0030] It is proposed that a height of the head part be smaller than a length of the radial end face of the lug in the circumferential direction. It is proposed that a height of the foot part be approximately the same as a length of the radial end face of the lug in the circumferential direction. It is further proposed that a height of the foot part be greater than a height of the head part, in particular 1-2.5 times greater, preferably 1.5-2 times greater. A height ratio in the radial direction of a height of the lug foot to the height of the head part can be around 1-2.5, in particular around 1.5-2. A head part has a height of 2.4 mm, for example, and a foot part has a height of 3.6-4.6 mm. In particular, the heights of the head part of all lugs of a tire are identical. Different heights of the foot part of different lugs, in particular lugs of different rows of lugs, can be different, for example.This is sometimes also done to enable a curved tire surface in the axial direction. An axially outer lug on the tire can, for example, have a higher root section than a lug that is more axially central. In particular, the root sections of the lugs of two outer rows of lugs distributed around the circumference of the tire, in particular, for example, a first and a fourth of the four rows, are higher, in particular 10-40% higher, preferably 20-30% higher, for example around 1 mm higher, than the root sections of the lugs of one or two middle rows, in particular, for example, the second and third rows of a tire with four rows of lugs. The height of the root section of this middle row can be, for example, 3.6 mm. Sinking behavior of the lug(s) or the tire, particularly in grass, can be improved in this way. The surface pressure exerted can be optimized. Damage, in particular to the turf, can be avoided.Traction can be improved.

[0031] It is proposed that transition areas from the tire's casing or base circle surface to the lug, in particular to the root of the lug, and / or that transition areas from the root to the head of the lug and / or that transition areas from the head to the front face of the lug are rounded or curved, in particular concavely or convexly rounded or curved. They can, for example, have a radius of curvature of 0.25 mm to 2.5 mm, preferably 0.5 mm or 1.5 mm. In transition areas between the tire's base circle surface and the root of the lug, the radius of curvature is, for example, 1.5 mm. This can improve the stability of the lug. Overloading, in particular in the root area or transition area between the casing or base circle surface and the lug root, can be avoided. Bending of the lug can be reduced.At the transition areas from the base to the head, as well as from the head to the front of the stud, the radius of curvature is 0.5 mm. This prevents damage to grass blades, for example.

[0032] In particular, a radius of curvature is formed between only three of four sides of the lug, in particular at three substantially right-angled transition regions of the side surfaces to one another, in particular viewed in the circumferential direction around the radial axis of the lug and / or the side surfaces to the front surface. It is proposed that, for example, no radius of curvature is arranged on a side of the respective lug or the lugs of the respective row of lugs facing the axial center of the tire, in particular in the transition region to the side surfaces adjacent in the circumferential direction around the radial axis or in the transition region to the radial front surface. This in turn can prevent drifting or slipping, for example when driving sideways on slopes. The axial center of the tire can be defined by a radius perpendicular to the direction of rotation orA plane formed along the tire axis that intersects the axial center of the tire, in particular centrally between a second and third row of lugs. The axial center is axially spaced substantially equidistant from the axial end faces of the tire. Sinking behavior of the lug(s) or tire, particularly in grass, can be improved. Damage, in particular to the turf, can be avoided. The strength of the lug(s) can be improved. The stability of the tire can be improved. Penetration or sinking of the lug, particularly between blades of grass, can be improved without damaging them, which could be caused, for example, by superficial seating and slipping on or bending of the blades of grass.

[0033] It is proposed that an axial end face of a lug on an outer side of the tire, in particular a lug in an outer or fourth row of lugs, is formed at an acute angle to the radial axis or at an acute angle to the axially opposite end face of the tire or has an angle to the radial axis. In particular, the angle is 4°. The outer end face tapers with increasing distance from the axis of rotation to the inner end face of the tire, in particular at an angle of 4°. This makes it easier to maintain the direction of travel. The outer side of the tire is defined in particular as the side facing away from a drive axis of the tire or wheel, or as the side facing away from the service robot. The inner side is defined in particular as the side facing the drive axis of the tire or wheel, or as the side facing the service robot.A tire can have a defined inner and outer side, in particular due to different axial end faces or the like. The tires can be designed for drive in both directions of rotation equally, in particular due to their circumferentially symmetrical structure (isosceles radially tapered or rectangular foot section, square or radially parallel head section or the like). This is advantageous because it makes the service robot equally suitable for forward and reverse travel. However, tires with studs according to the invention could also be provided or designed for unidirectional drive, in particular if one or more foot sections of the studs have an angled side surface or the like in only one circumferential direction.

[0034] It is proposed that an axial side surface of a lug, which is arranged adjacent to the axial center of the tire or oriented toward the axial center of the tire, runs radially or perpendicularly to the tire axis. In particular, it does not form an angle with the radial axis, but rather runs parallel to it. This can prevent the tire from drifting transversely to the rolling direction or running direction of the tire, especially on grass.

[0035] It is proposed that a projection of a cross-sectional area of ​​the root part of a lug that rests on the lateral surface or root circle surface of the tire, or a projection of a cross-sectional area of ​​a head part of a lug that supports an end face of the lug, projects beyond the end face on three perpendicular sides but not the fourth side in radial projection, in particular does not project beyond the tire axis in radial projection, preferably with the fourth side of the end face not projecting beyond in projection being oriented towards the axial center of the tire. This can prevent a tendency of the tire to drift transversely to the rolling direction or running direction of the tire, in particular on grass.It is proposed that in the axial direction of the tire, lugs are arranged in four rows of lugs distributed over the circumference and that end faces of lugs of two of the four rows which are located outside or inside the axial center of the tire in the axial direction of the tire do not project their foot surface in radial projection towards the axial center of the tire.

[0036] It is proposed that the tire is formed in one piece and / or comprises thermoplastic polyurethane (TPU), in particular is formed therefrom.

[0037] Furthermore, a service robot is proposed, in particular a lawnmower robot or a wheel with a rim and / or hubcap, comprising at least one aforementioned tire.

[0038] Tire (10) for a service robot (100), in particular a lawnmower robot tire (12), comprising a plurality of studs (22) distributed over the circumference of the tire (10), wherein a stud (22) has a foot part (24) which is based on a circumferential or base circle surface (26) of the tire (10) and a head part (28) which has a particularly radial end or tread surface (29) of the stud (22), in particular carries or forms a radial end or tread surface (29) of the stud (22) or tire (10), characterized in that a side surface (30) of the foot part (24) of the stud (22), with respect to a radial axis (36) of the stud (22), has an orientation which substantially spreads out from the circumferential or base circle surface (26), and a side surface (32) of the head part (28) of the stud (22), with respect on the radial axis (36) of the stud (22), a substantially non-spreading,preferably has an orientation substantially parallel to the radial axis (36).

[0039] Tire (10) at least according to the preamble of claim 1, in particular according to claim 1, characterized in that a side surface (30) of the foot part (24) is aligned substantially at an angle or obliquely to a radial axis (36) of the stud (22) and a side surface (32) of the head part (28) is aligned substantially parallel to the radial axis (36) of the stud (22), in particular side surfaces (30, 32) of the stud (22) pointing in the circumferential direction (48) of the tire (10).

[0040] Tire (10) according to at least one of claims 1 or 2, characterized in that the side surface (30) of the foot part (24) is aligned at an acute angle to the radial axis (36) of the stud (22), in particular having an angle (46) of 5-45°, preferably of 10-20°, particularly preferably of around 15°, in particular wherein the angle (46) tapers at an acute angle radially outwards.

[0041] Tire (10) according to at least one of the preceding claims, characterized in that opposite side surfaces (30) of the foot part (24) of the stud (22) in the circumferential direction (48) are aligned at an angle, in particular at an acute angle, preferably at an isosceles angle to one another.

[0042] Tire (10) according to at least one of the preceding claims, characterized in that the basic shape of the stud (22) about the radial axis (36) is substantially quadrangular, in particular wherein the sides of the quadrilateral are aligned parallel and perpendicular to the axis of rotation (38) of the tire (10), preferably wherein a basic shape of the foot part (24) is substantially trapezoidal-prism-shaped and a basic shape of the head part (28) is substantially cuboid-shaped.

[0043] Tire (10) at least according to the preamble of claim 1, in particular according to one of the preceding claims, characterized in that the stud (22) has, in an axial sectional plane (50) perpendicular to the axis of rotation (38) of the tire (10), a substantially isosceles trapezoidal foot part sectional surface (52) and a substantially rectangular or square head part sectional surface (54).

[0044] Tire (10) at least according to the preamble of claim 1, in particular according to one of the preceding claims, characterized in that the foot part (24) of the stud (22) is substantially trapezoidal-prism-shaped or truncated pyramid-shaped, and the head part (28) is substantially cuboid-shaped or cube-shaped; or that the foot part (24) is substantially frustoconical and the head part (28) is substantially cylindrical.

[0045] Tire (10) at least according to the preamble of claim 1, in particular according to one of the preceding claims, characterized in that the stud (22) has a substantially rectangular cross-sectional surface shape (96) in the region of the foot part (24) in radial sectional planes (AA, BB) perpendicular to the radial axis (36) of the stud (22) and a substantially square cross-sectional surface shape (98) in the region of the head part (28), preferably with a longer side (60) of the rectangular cross-sectional surface shape (96) of the foot part (24) being aligned in the circumferential direction (48) of the tire (10).

[0046] Tire (10) according to at least one of the preceding claims, characterized in that a height (40-1) of the foot part (24) in the radial axis direction (36) is greater than a height (40-2) of the head part (28), in particular between 1-2.5 times greater, preferably 1.5-2 times greater, preferably wherein a height (40-1) of the foot part (24) is 3.6-4.6 mm and a height (40-2) of the head part (28) is 2.4 mm.

[0047] Tire (10) according to at least one of the preceding claims, characterized in that at least one transition region (62) from the circumferential or base circle surface (26) of the tire (10) to the lug (22), in particular to at least one side surface (30, 72a, 72b, 72c, 72d) of the lug (22), in particular to at least one side surface (30) of the foot part (24) of the lug (22) and / or a transition region (64) from the foot part (24) to the head part (28) of the lug, in particular from a side surface (30) of the foot part (24) to a side surface (32) of the head part (28) of the lug (22), and / or a transition region (66) from the head part (28) to the front or tread surface (29) of the lug (22), in particular from at least one side surface (32) of the head part (28) of the lug (22) to the front or running surface (29) of the stud (22), is rounded, in particular concavely or convexly rounded, in particular having a radius of curvature (68, 70) of 0.25 mm to 2 mm,preferably of 0.5 mm or 1.5 mm, preferably wherein a concave or convex transition region (67-1) is formed on only three of four sides (72a, 72b, 72c) of the stud (22), in particular not formed on a side (72d) of the stud (22) facing the axial center (74) of the tire (10).

[0048] Tire (10) at least according to claim 10, characterized in that the transition region (67-1, 67-2) between side surfaces (72a, 72b, 72c, 72d) of the lug (22) which adjoin one another in the circumferential direction (65) about the radial axis (36) is not rounded at least on one side (72d), in particular at the transition region to the side (72d) of the lug (22) facing the axial center (74) of the tire (10), preferably both on the head and foot part (24, 28).

[0049] Service robot (100), in particular lawnmower robot (102), or wheel with rim and / or hubcap (16), comprising at least one tire (10) according to one of the preceding claims. drawing

[0050] Further advantages will become apparent from the following description of the drawings. The drawings illustrate at least one embodiment of the invention. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will conveniently consider the features individually and combine them into further meaningful combinations. They show: Fig. 1 a service robot according to the invention, in particular a lawnmower robot, with a tire according to the invention, in particular a lawnmower robot tire, or a wheel according to the invention with a rim and / or hubcap, Fig. 2 a first view of the tire according to the invention in a side view, or in an axial projection view along the axis of rotation of the tire, Fig. 3 an enlarged section of the tire according to Fig. 2, Fig. 4 a plan view of the tire according to the invention, so to speak of the profile and / or circumferential surface of the tire, in particular perpendicular to the axis of rotation of the tire, Fig. 5 a perspective view of the tire according to the invention, Fig. 6 a radial section AA through a head part and radial section BB through a foot part of a tunnel and Fig. 7 an axial section CC through a tunnel. Description of the embodiment

[0051] Fig. 1 shows a service robot 100 according to the invention with a tire 10 according to the invention. Tires 10 are arranged on both sides in the rear area of ​​the service robot 100 as drive tires (only one side is shown here). However, tires 10 could also be arranged on the front, in particular as an all-wheel-drive service robot, or with casters, in particular trailing rollers at the rear. The service robot 100 is an autonomous lawnmower or robotic lawnmower 102. The tire 10 is a drive tire, in particular a robotic lawnmower tire 12, or a robotic lawnmower drive tire. The service robot 100 has a housing 104. It has a chassis 106. The service robot 100 has a drive unit 108 for driving the drive wheels 14, in particular electric motors, preferably for individual wheel drive of the wheels. The drive wheels 14 comprise the tires 10 according to the invention.The service robot 100 has a power supply unit 112, for example a battery pack, in particular a handheld power tool interchangeable battery pack. The service robot 100 has rollers 114 at the front, which are not driven here and are designed in particular as trailing rollers. The service robot 100 steers via the independent wheel drive of the rear wheels. The service robot 100, here in the form of an autonomous lawnmower 102, further has a drive unit 110 for driving a tool, in this case a cutting unit 116. However, it could also have a drive unit 110 for driving another service unit. The service robot has a control and / or regulating unit 118. It has sensors or a sensor unit (not shown), in particular for detecting its surroundings and / or marking or boundary elements (also not shown here). It has a navigation unit (not shown), in particular for navigating independently.The service robot 100 can have a variety of additional features that are generally known to those skilled in the art familiar with service robots 100 or robotic lawnmowers 102. The service robot 100 or robotic lawnmower 102 is configured to independently perform a service in a work environment, in particular to independently mow a lawn. The tire 10 is mounted on a rim (not visible), which is concealed by a hubcap 16. An outer side 18 of the tire 10 is visible, and an inner side 20 faces the chassis 106 and is visible in later figures.

[0052] The tire 10 has a plurality of lugs 22 distributed around the circumference of the tire. A lug 22 includes a root portion 24, which rests on a circumferential or base circle surface 26 of the tire 10. A lug 22 includes a head portion 28, which has a radial face or tread 29. This forms part of a rolling or running surface of the tire 10. The head portion 28 supports or forms a face that serves as the tread of the lug 22 or tire 10. A side surface 30 of the foot part 24, or of the foot part 24 of the stud 22, has a different orientation 34 than a side surface 32 of the head part 28 of the stud 22, in particular relative to a radial axis 36 of the stud 22. Preferably, adjacent or mutually adjoining side surfaces 30, 32 of the foot part 24 and head part 28 in the radial axis direction have different orientations 34.The orientation 34 is to be understood as an orientation when viewed in the direction of the radial axis 36 of the lug 22. A radial axis 36 of the lug 22 intersects the rotational axis 38 of the tire 10 essentially perpendicularly. Thus, an orientation 34, 35 of adjacent or adjacent side surfaces 30, 32 of the foot part 24 and head part 28 in the direction of the radial axis 36 is different. The orientation 34, 35 is to be understood as an orientation when viewed in the direction of or along the radial axis 36 of the lug 22. A radial axis 36 of the lug 22 intersects the rotational axis 38 of the tire essentially perpendicularly. The radial axis 36 of the lug 22 extends substantially in the radial direction of the tire 10. Each lug 22a, 22b, 22c, 22d has a radial axis 36a, 36b, 36c, 36d and is intersected centrally by the radial axis 36a, 36b, 36c, 36d oriented substantially perpendicular to the axis of rotation 38.A height 40 of the stud 22 is measured in the direction of the radial axis 36. It is composed of the height 40-1 of the base part 24 and the height 40-2 of the head part 28. The orientation of the side surfaces 32 of the head part is essentially parallel to the radial axis 36 of the stud 22. The orientation 34 of the side surfaces 30 of the base part 24 is oriented at an acute angle to the radial axis 36, particularly tapering in a radially outward direction. The base part 24 expands toward the rotation axis 38. The cross-sectional area of ​​the head part 28 of the stud 22 thus remains essentially constant in the radial axis direction. The cross-sectional area of ​​the foot part 24 of the lug 22, however, increases in the radial axial direction from the transition region to the head part 28 towards the casing or base circle surface 26 of the tire 10, in particular linearly or potentially.The other orientation 34 of the side surfaces 30 of the base portion 24 of the lug 22 can produce a lifting effect under the influence of, for example, a driving or torsional moment on the tire 10. In the present embodiment, all lugs 22 of the tire 10 have at least one base portion 24 and one head portion 28.

[0053] The foot part 24 of a lug 22 rests on the casing or base circle surface 26 of the tire 10. The respective head part 28 of a lug 22 is arranged radially on or mounted on the foot part 24, in particular being formed integrally with it. "Integral" should be understood in particular to mean at least materially connected and / or advantageously formed in one piece, such as by production using a single- or multi-component injection molding process. The head part 28 of the lug 22 has or carries or forms the radial end or tread 29. The radial axis 36 of a lug 22 is aligned normal to the end or tread 29 of the lug. In principle, the end or tread could also be formed from a different material, particularly with regard to resistance, for example a harder or softer material.In particular, the lugs 22 are designed such that they stand out radially from the base or lateral surface 26 of the tire 10, i.e., preferably stand outward in the radial direction. Each lug 22 has a radial axis 36 that runs substantially perpendicular to the axis of rotation 38 of the tire 10 and penetrates the center of the respective lug 22. The side surface 30 of the foot part 24 is oriented substantially at an angle to the radial axis 36 of the lug 22, or of the respective lug 22. The side surface 32 of the head part 28 is oriented substantially parallel to the radial axis 36 of the respective lug 22. The front or tread surface 29 of the lug is oriented normal to the radial axis 36. The aforementioned side surfaces 30, 32 point in the circumferential direction 48 of the tire 10. The basic shape of the studs 22 around its radial axis 36 is essentially square.Two opposing side surfaces 30, 32 of the head and foot parts 24, 28 of the stud point in opposite circumferential directions, two further opposing side surfaces 42, 44, in particular an outer and inner side surface 42, 44 of the stud 22 point in the axial direction or in the direction of the rotational axis 38 of the tire.

[0054] “Substantially angular” is to be understood here in particular as an orientation of a direction relative to a reference direction, in particular in a plane, wherein the direction comprises an angle with respect to the reference direction. Preferably, this angle can no longer be considered to be substantially parallel. “Substantially parallel” is to be understood here in particular as an orientation of a direction relative to a reference direction, in particular in a plane, wherein the direction has a deviation from the reference direction, in particular less than 8°, advantageously less than 5°, and particularly advantageously less than 3°. For example, the side surfaces 32 of the head part 28 here have an angle of 1°-2° with respect to the radial axis 36. This can enable easy demolding of the tire 10 or the lug 22 from the tool. Self-cleaning of the lugs can also be improved as a result.Damage to the substrate can be avoided. Side surfaces 32 on the head portion of the stud 22 are chamfered, for example, at 2° to enable good demoldability from the mold and / or to prevent dirt from sticking between studs adjacent in the circumferential direction 48 and / or to reduce damage to the substrate, such as grass.

[0055] A side surface 30 of a foot part 24 is formed or aligned in the circumferential direction 48 of the tire 10 at an acute angle to the radial axis 36 of the lug 22. Here, the angle 46 is approximately 15°. The angle 46 tapers radially outward at an acute angle.

[0056] In particular, opposite side surfaces 30 of the base part 24 of the stud 22 in the circumferential direction 48 are formed at an angle to one another, in particular at an acute angle to one another. Here, they form an angle 50 of 30° to one another. Preferably, opposite side surfaces 30 of the base part 24 are aligned at an isosceles angle to one another, in particular at an acute angle to the radial axis 36. However, it is conceivable that, for example, only one side surface 122, in particular one in contact with the ground and facing the main direction of travel 120 (cf. Fig. 1), is formed at an acute angle to the radial axis 36 of the lug. The opposite side surface of the lug 22 could then, for example, be formed substantially parallel to the radial axis 36 of the lug 22 (not shown or implemented here). This would allow for improved sinking behavior, but also sometimes improved or assured circumferential pressure behavior or propulsion behavior. This is particularly true for tires that have a single predominant direction of rotation. The angular orientation of this side surface 30 could also be different. The side surface 122 facing the main direction of travel 120 is preferably more angled than the side surface 124 facing away from the main direction of travel 120, or the like. This could vary the traction behavior in opposite directions of travel, as could the sinking behavior or damage behavior of the ground.Sometimes, a service robot that is stuck in a jammed position, for example, against an obstacle, could be easily freed in reverse by increasing traction. Due to the angled design of the side surface 30 of the base portion 24 of the lug 22 on both sides, the tire 10 can be used equally for both forward and reverse travel, thus achieving the corresponding advantages.

[0057] A tunnel 22, here as an example at tunnel 22a cf. Fig. 3 and in particular Fig. 7, has, in an axial sectional plane 50 perpendicular to the rotational axis 38 of the tire 10, a substantially isosceles trapezoidal root section surface 52 and a substantially rectangular or square head section surface 54. The legs 56 of the trapezoidal root section surface 52 advantageously form an angle of 90° minus the aforementioned angle 46 of 15° with the base side 58 of the substantially trapezoidal root section surface 52. An angle 46 of the trapezoidal sides or side surfaces 30 of the root section 24 of the stud 22 to the radial axis 36 is preferably 15° in each case, and the angle 50 of the trapezoidal sides or legs 56 to one another is 30°. For the substantially rectangular or square head part cutting surface 54, the legs of the square head part cutting surface 54 running in the direction of the radial axis 36 run substantially parallel to one another.In essence, deviations are therefore generally permissible in the above-defined extent, in particular in order to enable tool demoldability during production or the like, for example by a 1-2° angle.

[0058] An angle 46 of the side surface 30 of the foot part 24, which is formed at an acute angle to the radial axis 36, can in particular be 15°. In principle, other acute angles of in particular 5-45°, preferably 10-25°, are also conceivable. Opposite side surfaces 30 of the foot part 24 of the tire 10 can, for example, each enclose an angle of 15° to the radial axis 36, or the side surfaces 30 of the foot part 24 can enclose an angle of 30° to one another. The side surface 30 of the foot part 24, in particular the opposite side surfaces 30 of the foot part 24, taper at an acute angle, in particular starting from the circumferential or base circle surface 26 of the tire 10, to the head part 28 of the lug 22. The foot part 24 of the lug 22 could in principle also be truncated conically (not shown here). In principle, the head part 28 could also be cylindrical.The foot section 24 and the head section 28 could both be truncated cones, with the angle of the cone of the foot section being larger than that of the head section. In particular, the foot section could have a significantly or much larger cone angle than the head section - for example, a cone angle of 0-30° in the area of ​​the head section and a larger cone angle of 20-60° in the area of ​​the foot section, preferably 0-10° at the head section, 20-40° at the foot section. This contrast could in principle also apply to a foot and head section that is trapezoidal in axial section. Or to antagonistically formed trapezoidal prisms of the foot and head sections with respect to the angles of the legs. Truncated pyramid-shaped foot and head sections with antagonistic leg angles would also be conceivable.In particular, the leg angle of the foot and head sections should differ by at least 10°, preferably 15-30°, with the angle of the foot section legs being less acute and the angle of the head section legs being more acute (i.e., more parallel). Other foot and head section body shapes are also conceivable.

[0059] As particularly in Fig. 3 in conjunction with Fig. 6, the studs 22 have, in radial section planes AA and BB, perpendicular to the radial axis 36 of the stud 22, a substantially different cross-sectional shape in the region of the foot part 24 than in the region of the head part 28. In particular, the cross-sectional shape BB is substantially rectangular in the region of the foot part 24 and the cross-sectional shape AA is substantially square in the region of the head part 28. The longer side of the rectangular cross-sectional shape BB of the foot part 24 extends in particular in the circumferential direction of the tire 10. In the circumferential direction, the studs 22 therefore each have a substantially quadrangular basic geometry, whereby “substantially” here is intended to imply that the corners of the quadrilateral can also be at least partially rounded.

[0060] It is further proposed that the base part 24 of the stud 22 be substantially trapezoidal prism-shaped or truncated pyramid-shaped and / or a combination thereof, and the head part be substantially cuboid-shaped or cube-shaped. As can be seen from the synopsis of the Fig. 2, Fig. 4 and Fig. As can be seen from Figure 7, the exemplary embodiment has studs 22 with such a shape. The trapezoidal prism-shaped or truncated pyramid-shaped base area of ​​the foot part 24 can, for example, be rectangular or square. Here, it is shown in Figure 7. Fig. 6, section BB is rectangular, in particular wherein the longer side of the rectangular, substantially trapezoidal prism-shaped or truncated pyramid-shaped foot part is aligned in the circumferential direction of the tire.

[0061] Furthermore, the base section can also be substantially frustoconical and the head section substantially cylindrical (not shown here). In radial sectional planes perpendicular to the radial axis of the stud, the cross-sectional areas in the region of the head section and the base section would then each be circular. Here, too, the side surfaces 30, 32 of the base and head sections 24, 28 are substantially angled or parallel to the radial axis 36.

[0062] The foot and head sections each have a certain height 40-1, 40-2. Together, they define a height 40 of the stud. It is proposed that a height 40-1 of the foot section 24 in the direction of the radial axis 36 be greater than a height 40-2 of the head section 28, in particular between 1 and 2.5 times greater, preferably 1.5 to 2 times greater.

[0063] A transition region 62a, 62b from the casing or base circle surface 26 of the tire 10 to the lug 22, in particular to at least one side surface 30 of the lug 22, in particular to at least one side surface 30 of the foot part 24 of the lug 22 and / or a transition region 64a, 64b from the foot part 24 to the head part 28 of the lug 22, in particular a side surface 30 of the foot part 24 to a side surface 32 of the head part 28 of the lug 22, and / or a transition region 66a, 66b from the head part 28 to the end face 29 of the lug 22, in particular from at least one side surface 32 of the head part 28 of the lug 22 to the end face 29 of the lug 22, is concave or convex, in particular having a radius of curvature 68, 70, preferably a radius of curvature 70 of 0.5 mm or a radius of curvature 68 of 1.5 mm. Preferably, a concave or convex transition region 62, 64, 66 is present on only three of four sides 72a, 72b, 72c (cf. Fig. 5) of the stud 22, in particular not formed at one of the axial centers 74 (cf. Fig. 4) of the tire facing side 72d of the lug 22. Through the axial center 74 runs according to Fig. 4 also the axial center plane 74a, which runs perpendicular to the axis of rotation 38 of the tire 10.

[0064] A radial end face or tread 29 of the lug(s) 22 is substantially square and / or a root surface 76 of the lug(s) 22 is substantially rectangular, in particular a root surface 76 of the lug(s) 22 where the lug(s) 22 rests on the lateral surface 26 or root circle surface of the tire 10. The longitudinal side 78 of the rectangular surface with the greater extent extends in particular in the circumferential direction 48. The radial end face 29 can also be substantially square, for example, because rounded portions 70a are provided between the side surfaces 72a, 72b, 72c of the head part 28 and the radial end face 29. Rounded portions 70a are in particular not provided on all sides of the substantially square head part 28, in particular not in the transition region to the side surface 72d.

[0065] Furthermore, in the axial direction 38 of the tire 10, the studs 22 are arranged in four rows 80a, 80b, 80c, 80d of studs 22a, 22b, 22c, 22d distributed over the circumference (cf. in particular Fig. 4). The studs 22a, 22b, 22c, 22d of each row 80a, 80b, 80c, 80d are arranged offset in the axial direction 38 and / or in the circumferential direction 48 relative to the studs 22a, 22b, 22c, 22d of the other rows 80a, 80b, 80c, 80d. They are, in particular, spaced apart without overlap and / or offset. Thus, in particular, they are offset relative to the studs 22a, 22b, 22c, 22d of the, in particular, directly axially adjacent and / or the, in particular, directly axially non-adjacent rows 80a, 80b, 80c, 80d.

[0066] In axial projection (cf. Fig. 2), i.e., projection along the rotational axis 38 or in the axial direction 38 of the tire 10, the lugs 22a, 22b, 22c, 22d are arranged sequentially in the circumferential direction 48 of the tire 10 such that a lug 22a of the axially first row 80a follows a lug 22b of the axially second row 80b, then a lug 22d of the axially fourth row 80d, and finally a lug 22c of the axially third row 80c. An axial offset 82a, 82b, 82c, particularly of immediately adjacent rows 22a, 22b, 22c, 22d, is unequal. An axial offset 82b of the two middle rows 80b, 80c, i.e. in particular the second and third row 80b, 80c to each other, is smaller than an offset 82a, 82c of the first to the second row 80a, 80b and / or the third to the fourth row 80c, 80d.In particular, an axial offset 82a, 82c of the first to the second row 80a, 80b and / or the third to the fourth row 80c, 80d is greater by a factor of 0.5-1.5, preferably by a factor of 0.75-1.25, than an offset 82b of the two middle rows 80b, 80c. In particular, an axial offset 82a of the first to the second row 80a, 80b is approximately 4.5 mm. An axial offset 82v of the third to the fourth row 80c, 80d can be approximately 3.5 mm. An offset 82b of the two middle rows 80b, 80c, i.e., the second to the third row 80b, 80c, is preferably approximately 2 mm.

[0067] Furthermore, in the circumferential direction 48, adjacent studs 22 of each of the four rows 80a, 80b, 80c, 80d are individually arranged at an angular distance 84a of 24° from one another and / or adjacent studs of all rows in axial projection (cf. Fig. 2) and viewed in the circumferential direction 48 of the tire 10, arranged at an angular distance 84b of 6° from one another, in particular wherein the lugs 22a, 22b, 22c, 22d of the first to the second row 80a, 80b and of the third to the fourth row 80c, 80d are arranged at an angular distance of 6° and wherein the lugs 22b, 22c of the second to the third row 80b, 80d are arranged at an angular distance 84c of 12°.

[0068] It is proposed that an axial width 86 of the tire 10 is 50-75% larger, in particular 65-70%, in particular around 2 / 3 larger, than an accumulated axial width 87a, 87b, 87c, 87d of four head or end faces 29a, 29b, 29c, 29d of each of a lug 22a, 22b, 22c, 22d of the four rows 80a, 80b, 80c, 80d and / or that an axial width 86 of the tire 10 is a factor of 5-8, preferably 6-7 times larger than an axial width 87a, 87b, 87c, 87d of a radial head or end face 29a, 29b, 29c, 29d of a lug 22a, 22b, 22c, 22d. In particular, an axial width 86 of the tire 10 is approximately 30 mm, and an accumulated axial width 87a, 87b, 87c, 87d of the radial head or end surfaces 29a, 29b, 29c, 29d of each of the four rows 80a, 80b, 80c, 80d is approximately 18-20 mm. In particular, an axial width 87a, 87b, 87c, 87d of an end surface 29a, 29b, 29c, 29d of a lug 22a, 22b, 22c, 22d is approximately 4.5-5 mm.

[0069] A height 40 of a stud 22, in particular starting from a base or lateral surface 26 of the tire 10 to the radial head or end surface 29 of a stud 22, is greater than a length 88 of a radial end surface 29 of the stud 22 in the circumferential direction 48 of the tire 10 (cf. in particular Fig. 3), in particular 1.5-2 times larger. A height 40-2 of a head part 28 of a stud 22 is smaller than a length 88 of a radial end face 29 of the stud 22 in the circumferential direction 48. A height 40-1 of a foot part 24 of a stud 22 is approximately the same as a length 88 of a radial end face 29 of the stud 22 in the circumferential direction 48. A height ratio in the direction of the radial axis 36 of a height 40-1 of the foot part 24 of the stud 22 to the height 40-2 of the head part 28 can be around 1-2.5, in particular around 1.5-2. A head part 28 has, for example, a height 40-2 of 2.4 mm and a foot part 24 has a height 40-1 of 3.6-4.6 mm. In particular, the heights 40-2 of the head portion 28 of all studs 22 of a tire 10 are identical.Different heights 40-1 of the foot part 24 of different lugs 22a, 22b, 22c, 22d, in particular lugs 22 of different rows 80a, 80b, 80c, 80d of lugs 22a, 22b, 22c, 22d, are preferably provided to enable a curved lateral surface of the tire 10 in the axial direction 38. An axially outer lug 22a, 22d of the tire 10 can, for example, have a higher root portion 24 than an axially more central lug 22b, 22c of the tire 10. In particular, the root portions 24 of the lugs 22 of two outer rows 80a, 80d of lugs 22a, 22d distributed over the circumference or in the circumferential direction 48 of the tire 10, in particular, for example, a first and a fourth of the four rows of lugs, are higher, in particular 10-40% higher, preferably 20-30% higher, for example, around 1 mm higher, than the root portions 24 of the lugs 22b, 22c of one or two middle rows 80b, 80c, in particular, for example, the second and third rows 80b, 80c of a tire 10.The height of the foot part 40-1 of these middle rows 80b, 80c of lugs 22b, 22c can be, for example, 3.6 mm. Transition regions 62 from the casing or base circle surface 26 of the tire 10 to the lug 22 are curved. They have, for example, a radius of curvature of 0.5 mm to 2.5 mm, preferably 0.5 mm or 1.5 mm. At the transition regions 64, 66 from the foot part 24 to the head part 28, as well as from the head part 28 to the end face 29 of a lug 22, the radius of curvature 70 is, for example, 0.5 mm. In particular, a radius of curvature is formed between only three of four sides of the lug 22, in particular at three substantially right-angled transition regions of the side surfaces to one another, in particular viewed in the circumferential direction around the radial axis 36 of the lug 22 and / or the side surfaces to the end face 29. The axial center plane 74a of the tire 10 can be defined by a plane perpendicular to the axis of rotation 38 orTire axis formed plane which intersects the axial center 74 of the tire 10. It lies in particular axially centrally between a second and third row of lugs 80b, 80c. The axial center 74 is substantially equidistant from the axial end faces 29 of the tire 10. An axial end face 89a of a lug 22a is formed on an outer side 18 of the tire 10 at an acute angle to the radial axis 36 and / or at an acute angle to the axially opposite outer side 18 or axially opposite inner axial end face 89d of the tire 10. In particular, the angle 90 is approximately 4°. The outer axial end face 89a tapers with increasing distance (radius) from the rotational axis 38 of the tire to the inner axial end face 89d of the tire 10, in particular at an angle 90 of 4°. The outer side 18 of the tire 10 is defined in particular as the side facing away from a drive unit 108 of the tire 10 or the wheel or the chassis 106.The inner side 20 is defined, in particular, as the side facing the drive unit 108 of the tire 10 or the wheel, or as the side facing the chassis 106 of the service robot 100. In the present exemplary embodiment, the inner diameter of the tire 10 relative to the wall of the outer side 18 is approximately 180-185 mm, in particular 182 mm. Fig. 3 shows the corresponding inner radius 92. An outer diameter 94 (up to the end faces 29) is approximately 220 mm - in Fig.3 also shows the corresponding outer radius 95. The outer diameter or base circle of the tire 10 is approximately 200-210 mm, in particular 204-208 mm, preferably due to a slightly spherical shape of the outer diameter or base circle surface in the axial direction 38 of the tire 10. The tire 10 is designed for drive in both directions of rotation, in particular due to the lugs 22 (isosceles tapered foot part, parallel head part, or the like) that are symmetrically constructed in the circumferential direction at least in each row 80a, 80b, 80c, 80d. This makes them equally suitable for forward and reverse travel.However, tires with studs according to the invention could also be provided for unidirectional drive or with different traction behavior when driving forward and backward, in particular by one or more studs whose foot parts had a side surface running at an angle to the radial axis only in one circumferential direction or had side surfaces with different angles or the like.

[0070] An axial side surface 72d of a lug 22, in particular of all lugs 22, which is / are arranged or oriented adjacent to the axial center 74 or axial center parting plane of the tire 10, runs perpendicular to the rotational or tire axis 38. Thus, they essentially do not form an angle with the radial axis 36, but rather run parallel to it. This can prevent, in particular, a tendency of the tire 10 to drift transversely to the rolling direction or running direction of the tire 10, especially on grass.

[0071] The tire is formed in one piece. It comprises, in particular, thermoplastic polyurethane (TPU) or is preferably formed from it. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 2 657 043 A1

[0001]

Claims

[1] Tire (10) for a service robot (100), in particular lawnmower robot tire (12), having a plurality of studs (22) distributed over the circumference of the tire (10), characterized by in that in the axial direction (38) of the tire (10) the studs (22) are arranged in four rows (80a, 80b, 80c, 80d) of studs (22) distributed over the circumference, wherein the studs (22a, 22b, 22c, 22d) of each row (80a, 80b, 80c, 80d) are arranged offset in the axial direction (38) and / or in the circumferential direction (48) with respect to studs (22a, 22b, 22c, 22d) of the other rows (80a, 80b, 80c, 80d), in particular are arranged spaced apart without overlapping and / or offset. [2] Tire (10) according to claim 1, characterized bythat the lugs (22) are arranged sequentially in axial projection and in the circumferential direction (48) of the tire (10) in such a way that a lug (22a) of the axially first row (80a) follows a lug (22b) of the axially second row (80b), then a lug (22d) of the axially fourth row (80d) and finally a lug (22c) of the axially third row (80c). [3] Tire (10) according to one of the preceding claims, characterized by that an axial offset (82a, 82b, 82c) of axially adjacent rows (80a, 80b, 80c, 80d) is unequal, in particular an axial offset (82b) of the two middle rows (80b, 80c), in particular of the second and third rows (80b, 80c) to one another, is less than an offset (82a, 82c) of the first to the second row (80a, 80b) and / or the third to the fourth row (80c, 80d). [4] Tire (10) according to one of the preceding claims, characterized bythat in the circumferential direction (48) adjacent lugs (22a, 22b, 22c, 22d) of each of the four rows (80a, 80b, 80c, 80d) are arranged at an angular distance (84a) of 24° from one another and / or the lugs (22a, 22b, 22c, 22d) of all rows (80a, 80b, 80c, 80d) in axial projection and viewed in the circumferential direction (48) of the tire (10) are arranged at an angular distance (84b) of 6° from one another, in particular wherein the lugs (22a, 22b, 22c, 22d) of the first to the second row (80a, 80b) and of the third to the fourth row (80c, 80d) are arranged at an angular distance (84b) of 6° from one another, preferably wherein the Studs (22b, 22c) of the second to the third row (80b, 80c) are arranged at an angular distance (84c) of 12° from one another. [5] Tire (10) according to one of the preceding claims, characterized bythat an axial width (86) of the tire (10) is 50-75% larger, in particular around 2 / 3 larger, than an accumulated axial width (87a, 87b, 87c, 87d) of four head parts (28) or end or tread surfaces (29) of each lug (22a, 22b, 22c, 22d) of the four rows (80a, 80b, 80c, 80d) and / or that an axial width (86) of the tire (10) is a factor of 5-8, preferably a factor of 6-7 larger than an axial width (87a, 87b, 87c, 87d) of a lug (22a, 22b, 22c, 22d) or of a radial head or end surface (29) of a lug (22a, 22b, 22c, 22d). [6] Tire (10) according to one of the preceding claims, characterized bythat a height (40) of a lug (22), in particular starting from a circumferential or base circle surface (26) of the tire (10) to the radial head or end face (29) of a lug (22), is greater than a length (88) of a radial end face (29) or a length (88) of the head part (24) of the lug (22) in the circumferential direction (48) of the tire, in particular by 1.5-2 times greater; and / or that a height (40-2) of a head part (28) of a lug (22) is smaller than a length (88) of a radial end face (29) or a length (88) of the head part (28) of the lug (22) in the circumferential direction (48); and / or that a height (40-1) of a foot part (24) of a stud (22) is approximately equal to a length (88) of a radial end face (29) or a length (88) of the head part (28) of the stud (22) in the circumferential direction (48). [7] Tire (10) according to one of the preceding claims, characterized bythat the base part (24) of the stud (22) is substantially trapezoidal prism-shaped or truncated pyramid-shaped, and the head part (28) is substantially cuboid-shaped or cube-shaped; or that the base part (24) is substantially truncated cone-shaped and the head part (28) is substantially cylindrical. [8] Tire (10) according to one of the preceding claims, characterized bythat at least one transition region (62) from the casing or base circle surface (26) of the tire (10) to the lug (22), in particular to at least one side surface (30, 72a, 72b, 72c, 72d) of the lug (22), in particular to at least one side surface (30) of the foot part (24) of the lug (22) and / or a transition region (64) from the foot part (24) to the head part (28) of the lug, in particular a side surface (30) of the foot part (24) to a side surface (32) of the head part (28) of the lug (22) and / or a transition region (66) from the head part (28) to the front or tread surface (29) of the lug (22), in particular from at least one side surface (32) of the head part (28) of the lug (22) to the front or tread surface (29) of the Stud (22), rounded, in particular concavely or convexly rounded, in particular having a radius of curvature (68, 70) of 0.25 mm to 2 mm, preferably of 0.5 mm or 1.5 mm,preferably wherein a concave or convex transition region (67-1) is formed on only three of four sides (72a, 72b, 72c) of the stud (22), in particular not formed on a side (72d) of the stud (22) facing the axial center (74) of the tire (10)., [9] Tire (10) according to one of the preceding claims, wherein the tire (10) is formed in one piece and / or comprises thermoplastic polyurethane (TPU), in particular is formed therefrom. [10] Service robot (100), in particular lawnmower robot (102), or wheel with rim and / or hubcap (16), comprising at least one tire (10) according to one of the preceding claims.

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