WO2025248135A1

WO2025248135A1 - Joint with gear

Info

Publication number: WO2025248135A1
Application number: PCT/EP2025/065086
Authority: WO
Inventors: Bartolomej Janek
Original assignee: Individual
Current assignee: Individual
Priority date: 2024-05-31
Filing date: 2025-05-30
Publication date: 2025-12-04
Anticipated expiration: 2026-11-30

Abstract

The present invention is directed to a device, in particular robot joint, with first arm, with second arm, with base body and with conductors passing from the first arm to the second arm wherein the conductors are at least partially positioned along the periphery of the base body.

Description

Joint with Gear

The invention relates to a robot joint of anthropomorphic structure, inparticular characterized in that the arms of the robot perform a swiveling motion relative to each other. The robot joint according to the invention, comprises a first arm (1 ), a transmission (3) and a second arm (2), the input shaft of the transmission is coaxially linked with a motor (4), a brake and an angular encoder (5). Second angular encoder is linkable with the first and second arms (1 ), (2) to get mutual angular position of arms (1 ) and (2). Thanks to the non-hollow achitecture of the robot joint the invention comes with significant reduction of i) friction under seals (50t) mounted on the input shaft (50) and ii) inertia related loses on the input shaft (50). The signal and power transmission means/conductors (7) passing through the robot joint are routed from the first arm (1 ) to the second arm (2) circumferentially to the base body (10) of the transmissio (3). The hole in the input shaft as a way for getting the conductors through the joint is no more needed. The transmission (3) of the robot joint is characterized by an outstanding flat design envelope and low weight resulting in high power transmission density. Invention brings a novel way of connecting the output parts (20) and (20') of the transmission enabling design of dimensionally restricted robot joints. A new morphology of the transformation member (30) transforming planetary motion of cycloidal gears (40) into rotary motion of output parts (20 ), (20') contributes significantly to increasing its torsional stiffness.

STATE OF THE ART Patent document DE 102004062334 describes a mutually immovable and force-locking connection of the flange portions (50), (50') of the output member of a transmission. The contact surfaces (53), (53') on the longitudinal parts (52), (52') are shaped in the form of wave profiles, identically oriented in the direction of the axes (53a), 53'). The direction of these axes is determined by the direction of the surface lines (Flachenlinie) on the contact surfaces. The directional axes (53'a) on the opposite longitudinal parts (52') are parallel, as are the directional axes (53a) on the opposite longitudinal parts (52). The contact surfaces (53), (53') are complementary in shape. The force-locking connection removes only two degrees of freedom from the mutual movement of the flange parts (50), (50') in the plane perpendicular to the axis (40a) of the body (40), so that one of the flange parts (50), (50') cannot rotate relative to the other about the axis (40a), nor can one of the parts (50), (50') move relative to the other in the direction perpendicular to the directional axes (53a), (53'a). A condition for the mutual immobility of the flange parts (50), (50') is a sufficiently large force action in the connecting elements (60). The relative movement of the flange parts (50), (50') in the direction of the axes (53a, 53'a)) is limited exclusively by the axial forces in the coupling elements (60) and the coefficient of friction between the contact surfaces.

The first deficiency of the connection according to DE 102004062334 is the mutual radial positional creep in the direction of the axes (53a), (53'a). The positional creep is a small, mutual cumulative displacement of the flange portions (50), (50')), which arises when the fasteners (60) are insufficiently prestressed. Positional creep of the flange parts (50), (50') is an undesirable phenomenon leading to a change in the prescribed position of the transmission components and causing vibration and asymmetric wear of the components. The second drawback is axial positional creep (small mutual axial cumulative displacement) of the contact surfaces (53), (53'). It arises when the fasteners (60) are re-tightened and loosened, for example when the flange parts (50), (50') are assembled and re-assembled and disassembled. The consequence is an undesirable permanent change in the axial distance of the flange parts (50), (50') implying numerous deviations in the mounting tolerances of the transmission.

Document DE202021101820 describes a force-locking connection of flange portions (20), (30) of a transmission with axially oriented projections (21 ), (31 ) on which radially oriented recesses (23), (231 ) are formed, which longitudinal bodies (40) of cylindrical shape are formed. The essential problem of the solution according to the above cited document is that the connection using the cylindrical shape of the body (40) is unreliable, since there is no prevention of its loosening. The unreliability has its origin in non-self-assembly of the connection on the basis of the cylindrical body (40). The remedy would be a conical shape of the body (40) allowing self-locking connection, but such a shape in the case of the connection according to DE202021101820 is not applicable for obvious reasons. The second problem is that the connection of the flange portions (20), (30) according to the above cited document exhausts the force capacity of the connection of the flange portions (20), (30).

The remedy for the above-mentioned deficiencies of the state of the art is provided by the solution according to the present invention.

The current architecture of robot joints is characterized by the use of transmissions with a one- sided output shaft and one-sided input shaft, which usually has a large diameter through passing hole - "hollow shaft" design. A typical example bring collaborative robots, the joint architecture of which is based on a 'hollow shaft' design providing a transport route to get the signal and power conductors through the robot joint. The bigger is the diameter of thole inside the input shaft, the bigger is its inertia, which is the root cause of at least three base problems today's (ro)/(co)botics is facing to. i) the friction torque of the seals on the input shaft progressively grows with the sealing lip diameter. Increased friction on the seals means more heat generated and more motor torque needed to obtain requested acceleration in the robot's joint. Friction related losses imply a reduction of efficiency of the robot drives, (ii) Bigger sealing diameter implies higher sealing speed on sealing lips and consequently higher risk of leakage. Even small lubricant leakage is considered to be a critical system failure. iii) The input inertia of the input shaft increases with the fourth power of its outer diameter. High inertia has a dramatic impact on the dynamic efficiency of the robot drives and increases the torque capacity of the motor in robot joints needed to achieve requested dynamic motion performance of robot. The robot joint according to the invention brings an efficient remedy to the state of the art.

Preferably, a device, in particular robot joint, with first arm (1 ), with second arm(2), with base body (10) and with conductors (7) passing from the first arm (1 ) to the second arm (2) is provied characterized in, that the conductors (7) are at least partially positioned along the periphery of the base body (10).

Preferably, arobot joint according with the base body (10) rotatably supporting the output body (20o) of the transmission (3) with two mutually connectable output parts (20,20') rotatably supporting input shaft (50) having two eccentric parts with external gears (40), which have an outer cycloidal toothing (41 ) meshing with inner toothing (11 ) of the base body (10), with a transformation body (30) to transform planetary motion of external gear (40) into rotary motion of output parts (20,20') is provided characterised in that the first arm (1 ) is toughly connected to the base body (10) while the second arm (2) is toughly connected to the output parts (20,20'), the conductors (7) swivel synchronously with the second arm (2) over the periphery of base body (10), or are on the periphery stationary. Preferably, the rotor (4r) of motor (4), the rotatable part (5o) of angular encoder (5) are coaxially connected to the input shaft (50).

Preferably, the rotor (4r) of motor (4), the rotatable part (5o) of angular encoder (5) and the clamping part (6o) of brake (6) are coaxially linkable to the shaft (50) via the shaft extensions (50a), (50b), second angular encoder may be placed in the robot joint coaxially to axis (10a) to identify angular position of first arm (1 ) with respect to the second arm (2).

Preferably, the motor winding (4) and the parts of the angular encoder (5) and the brake (6) stationary to second arm (2) are coaxially and non-rotatably connected to said second arm (2) of the robot joint,

Preferably, the conductors (7) are positioned in a cavity (10k) formed on outer periphery of the base body (10), said cavity (10k) is advantageously of rectangular, or oval like cross-section.

Preferably, said conductors (7) are positioned in the cavity (10k) via a guidance guard (71 ), wherein the conductors (7) get out from the periphery space of the base body (10) and enter the output space (2s) of the second arm (2) through a transit hub (to).

Preferably, there are seals (13) between the output parts (20), (20') and the base body (10),

Preferably, the second arm (2) of the robot joint is coaxially mounted in the outlet portions (20), (20') via centering bodies (20c), annular in shape and having seals (50t) mounted on the inner circumference,

Preferably, the base body (10) has a heel portions (1 Op) to which the first arm (1 ) of the robot joint is connected.

Preferably, the rolling bodies (54) on the eccentric portions (51 ) of the input shaft (50) are axially guided by adjacent front surface of the transformation member (30), Preferably, the cylindrical rolling bodies (55) on the centric portions of the shaft (50) are axially guided by the adjacent face of the transforming member (30),

Preferably, the internal ttothing (11 ) comprises longitudinal pins of even number N, the pins are cylindrical in shape with an individual spacing approximately equal to or less than twice the diameter of the longitudinal pins, wherein the gear ratio i of the transmission is equal to 2N-1 .

Preferably, the transformation member (30) has the shape of a plate with a tetragonal base, with central opening (33), with linear guideways (34a) lateral to the vertices of the tetragonal base, mutually opposite, parallel to each other and spaced apart from each other by an offset (w), wherein the ratio of the offset (w) of the linear guiding surfaces (34a) to double of diameter of the rolling elements (31 ) is less than 1 .

Preferably, on the guiding surfaces (34a) there are cylindrical bodies (31 ) having a diameter greater than the length of the guiding surfaces (34a), said guiding surfaces (34a) terminate at the profile portions (37) wherein the shortest distance (b) of opposite profile portions (37) is less than or equal to the perpendicular offset (w) of the guiding surfaces (34a).

Preferably, the rolling bodies (31 ) have a central circular bore (32) for the cylindrical pins (36), the diameter of the bore (32) and the diameter of the pin (36) being (approximately) the same, on at least one of the flanges (20), (20') and the external gear (40) adjacent thereto, there are longitudinal recesses (26) between the guideways (34a) in which the pins (36) are slidably guided and which limit the positional creep of the rolling bodies (31 ) at their ends.

Preferably, the shape-locking connection of the output portions (20), (20') have axially oriented pairs longitudinal portions (22a, 22'a), (22b, 22'b), (22c, 22c), (22d,22'd ) on which there are pairs of shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd), wherein the directional axes (23a, 23c), (23b, 23d) and (23'a, (23'c), (23'b, 23'd) of the shape-complementary profiles opposite with respect to the axes (20a), (20'a) are non-parallel/non-colinear in the projection onto a plane perpendicular to the axis (10a).

Preferably, the normal vectors (na, nc), (nb, nd), (n'a, n'c), (n'b, n'd) of the planar working surfaces (243a, 243c), (243b, 243d) and (243 a, 243 c), (243'b, 243'd) on shape complementary profiles (24a), (24c), (24b), (24d) and (24'a), (24'c), (24'b), (24 'd) are oriented perpendicularly to axis (10a), where the pairs of normal vectors (na, nc), (nb, nd) opposite with respect to the axis (20a) enclose angles (02, a 1) different from zero and different from 180° , respectively, and the pairs of normal vectors (n'a, n'c), (n'b, n'd) opposite with respect to the axis (20'a) enclose angles (02, a 1) different from zero and different from 180,

Preferably, the mutual contact position of the pairs of shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24 'd) axially force-free connected removes three degrees of freedom of the output part (20) with respect to the output part (20') in a plane perpendicular to the axis (10a).

Preferably, the mutually contact position of the pairs of shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd) in the working state is ensured by the screws (70).

Preferably, the directional axes (23a), (23b), (23c), (23d) and (23'a), (23'b), (23'c), (23'd) of the shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd) pass perpendicularly through the axis (10a).

Preferably, on the opposite pairs of shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd) there are surfaces with holes (242a, 242'a), (242b, 242'b), (242c, 242'c), (242d, 242'd) for the connecting elements (70), which are contactable in the working condition of the transmission.

Preferably, a force-locking connection of the output parts (20), (20'), with axially oriented portions (22a), (22b), (22c), (22d ) and (22'a), (22'b), (22'c), (22'd), is provided on which there are pairs of shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd), wherein the directional axes (23a, 23'a), (23b, 23'b) and (23b, 23'b), (23c, 23'c) of the complementary profiles opposite to each other with respect to the axis (20a), (20'a) are non-parallel/non-colinear in projection to a plane perpendicular to the axis (10a).

Preferably, the directional axes (23a, 23'a), (23b, 23'b) and (23b, 23'b), (23c, 23'c) of the shape complementary profiles (24a, 24 'a), (24b, 24 'b), (24c, 24 'c), (24d, 24 'd) pass perpendicularly through the axis (10a).

Fig. 1 axial layout of a robot joint according to the invention

Fig. 1.1 placement of guidance guard in the peripheral cavity

Fig. 2 radial layout of a robot joint according to the invention

Fig. 3 morphology of the transformation member and its placement in the output part of the transmission

Fig. 4 Prevention of positional creep of rolling bodies in linear guides

Fig. 5 Rolling body of linear guide with position creep prevention.

Fig. 6 Output body with output parts in the shape-locked connection

Fig. 7,8,9 3D morphology of the shape-locking connection of the output parts

Fig.10,11 Frontal view of output parts with indication of directional angles shape- locked complementary profiles.

Fig.12 3D morphology of output parts with force-locking complementary profiles

Fig.15, 16 Front view of the output parts with indication of directional angles of the force locked complementary profiles. A device with first arm (1 ), with second arm(2), with base body (10) and with means for transferrin the energy and control signals/conductors (7) passing from the first arm (1 ) to the second arm (2) characterized in, that the conductors (7) are at least partially positioned along the periphery of the base body (10).

Robot joint on Fig.1 , Fig.1.1 and Fig.2 comprise of a first arm (1 ), a second arm (2) and a transmission (3) with a motor (4), an angular encoder (5) and a brake (6), optionaly second angular encoder. The first arm (1 ) is connected to the base body (10) of the transmission (3), the second arm (2) is connected to the output parts (20), (20') of the transmission (3), wherein the output parts are fixedly connected by the longitudinal parts (22a) and (22'a) and rotatably mounted in the base body (10). The base body (10) has heel portions (10p) with a clamping surface (10u) by which the body (10) is toughly connected to the first arm (1 ) by means of connecting members (10s). The transmission (3) has an input shaft (50) rotatably mounted in the output parts (20), (20') via rolling bodies (55), wherein there are rolling bodies (54) mounted on the eccentric portions (51 ) of the input shaft (50), on which external gears (40) are rotatably supported, external gear (40) have on its periphery a cycloidal toothing (41 ), which engages with the inner toothing (11 ) of the base body (10), wherein between the external gear (40) and the adjacent output portion (20), (20') is a member (30) transforming the planetary motion of the external gear (40) into a rotational movement of the output parts (20), (20') about the axis (10a) of the base body (10).

The inner toothing (11 ) is formed by longitudinal pins of cylindrical shape with an individual spacing approximately equal to or less than twice the diameter of the pins. Advantageously, for an even number N of pins, the gear ratio i of the transmision is equal to 2N-1 .

There is a cavity (10k) formed on outer periphery of the base body (10), which is advantageously of rectangular, or oval like in cross-section. Means (7) for transferring energy and signals from the input space (1s) of the first arm (1 ) to the output space (2s) of the second arm (2) are arranged circumferentially to the base body (10), The conductors (7) are arranged in the cavity (10k) by a guidance guard (71 ), get out from the periphery space of the base body (10) and enter the output space (2s) of the second arm (2) via a transit hub (to). Conductors (7) may swivel synchronously with the second arm (2) over the periphery of the base body (10), or may be on the periphery non-swivelling. The rotor (4r) of motor (4), the rotatable part (5o) of angular encoder (5) and the clamping part of the brake (6) are coaxially linkable to the input shaft (50) via the shaft extensions (50a), (50b). Second angular encoder may be placed in the robot joint coaxially to axis (10a) to measure the angular position of first arm (1 ) with respect to the second arm (2).

The motor winding (4) and the parts of the angular encoder (5) and the brake (6) stationary to second arm (2) are coaxially and non-rotatably connected to said second arm (2) of the robot joint, The motor rotor (4r) and the rotatable part (5o) of the encoder are mounted on a first shaft extension (50a) and coaxially linked to the input shaft (50) - Fig.1. The members (20c) center the second arm (2) relative to the gear (3) and support the seals (50t) on the inner circumference. The transmission (3) is sealed on both sides on the outer circumference of the output parts (20), (20') by seals (13).

The joint architecture of the robot according to the invention is based on a two-sided output of the shaft (50). Its first extension (50a) protrudes the contour of the output member (20) on the left hand side and by its second extension (50b) protrudes the contour of the output member (20') on the right hand side. Advantageously, the input shaft (50) is accessible from both sides of the robot joint, which greatly simplifies access to the input shaft (50) when mounting/servicing the motor (4), encoder (5) or brake (6).

The robot joint according to the invention is based on a 'non-hollow' design cocncept of the input shaft (50), which substantially solves the problems related to the state of the art. The bore (50c) of the shaft (50) has a small diameter and thus the shaft (50) does not belong into the category of a 'hollow shaft '-Fig.1 . The outer diameters of the input shaft (50) and both extensions (50a), (50b) can be set to a minimum value. The friction on the seals (50t) is reduced down to a half compared to the hollow shaft concept, the input inertia of the shaft (50) including the both extensions (50a), (50b) is reduced down to a third and the heat generated by Joule loses in motor winding during acceleration and braking is reduced down to a tenth compared to the 'hollow shaft' solution. The efficiency of the robot joint increases up and the risk of leakage at the seals are decreased accordingly.

The transmission (3) of the robot joint according to the invention has rolling bodies (54) on the eccentric portions (51 ), which can be axially guided by the front surface of the adjacent transformation member (30) - Fig. 1. The rolling bodies (55) on the centric parts of the input shaft (50) can be axially guided by the front surface of the adjacent transformation member (30) - Fig. 1. Axial guidance by front faces of transformation member (30) significantly reduces the width of the transmission (3) and reduces significantly its weight.

The new design morphology of the transformation member (30) of the transmission (3) according to the invention significantly increases its overall torsional stiffness. The transformation member (30) has the shape of a plate having a tetragonal base with a central opening (33). There are linear guideways (34a) lateral to the vertices of the teragonal base with rolling bodies/elements (31 ) whose diameter is greater than the length of the guideway (34a), Fig.3, Fig.4. The guideways (34a) terminate on profile portions (37), wherein the shortest distance (b) of the opposing profile portions (37) is less than or equal to the perpendicular distance w of the guideways (34a). The rolling bodies (31 ) according to the invention have a central circular hole (32) for the cylindrical pins (36), wherein the diameter of the hole (32) and the diameter of the pin (36) are (approximately) the same Fig. 4, Fig.5. On at least one output part (20), (20') and on the external gear (40) adjacent thereto, there are longitudinal recesses (26) between the guideways (34a) in which the pins (36) are slidably guided and which are arranged such that the positional creep of the bodies (31 ) is limited at the ends of the recesses (26). The sides of the tetragon (38) are linear with width W or are arcuate - Fig.3. The ratio of the distance/offset w of the linear guideways (34a) to the double of diameter of the rolling elements (31) is less than 1, in a boundary case is less than 1.3. Number of rolling elements on the guideway (34a) is equal to one. An advantage of the solution according to the invention is that the structural bending stiffness of the tetragonal shaped plate of the transformation member (30) in a central plane paralel to the face plane is substantially higher compared to the corresponding bending stiffness of the open cross-shaped structures known in the prior art. This is due to the relative metrics of the transformation member (30): the ratio of the double of the length of guideways (34a) to the diameter described over the vertices of the tetragon is substantially less compared to the ratio of the transformation members seen at the state of the art. The same applies for the size of the sides W of the tetragon and for the size of radius of the the profile portion (37).

A new method of shape-locking connection of the output parts (20 ), (20') of the output body (20o) of the transmission (3) is applied within the invention. The shapelocking connection Fig.6, Fig.7 removes three degrees of freedom of the output parts (20), (20') in a plane perpendicular to the axis (10a): one output part (20), (20') cannot rotate relative to the other around the axis (10a) and at the same time cannot move relative to each other in the radial direction without the force action of the connecting elements (70) - Fig.6 The connecting element transmits the axial forces generated by external forces and at the same time ensures the position of the mutual contact of the opposite shape-complementary profiles in the working state. The output parts (20), (20') are rigidly connected Fig.6, Fig.7 by axially oriented pairs of longitudinal parts/portions/protrusions (22a,22'a), (22b, 22'b), (22c,22'c), (22d,22'd) passing through the peripheral holes of the external gears (40). The direction of the transverse oscillatory motion of the transformation member (30) is determined by the axes (20a), (20'a) - Fig.7, which are also the axes of the linear guiding of the transformation member (30) in the output portions (20), (20'). The shape-locking connection of the output parts (20), (20') is provided by pairs of opposite shape-complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd) formed on the longitudinal parts (22a,22'a), (22b, 22'b), (22c,22'c), (22d,22'd). On the shape-complementary profiles there are planar working surfaces (243a, 243'a), (243b, 243'b), (243c, 243'c), (243d, 243'd), whose normal vectors (na, n'a), (nb, n'b), (nc, n'c), (nd, n'd) are oriented perpendicular/transverse to the axis 10a of Fig.10, Fig.11 . The magnitude of the angle a2, which the normal vectors n'a, n'c make with respect to each other in the projection onto the plane perpendicular to the axis 10a, is different from zero, or is different from 180 degrees. Similarly, the magnitude of the angle a1 mutually enclosed by the normal vectors n'b, n'd in the projection onto the plane perpendicular to the axis 10a is different from zero, respectively it is different from 180 degrees - Fig.11 . The same applies for the angles mutually taken by the vectors na, nc and the vectors nb, nd on the output part 20 of Fig. 10.

On the working surfaces (243a, 243'a), (243b, 243'b), (243c, 243'c), (243d, 243'd), lie the directional axes (23a, 23'a), (23b, 23'b), (23c, 23'c), (23d, 23'd), which are perpendicular to the normal vectors of the contact surfaces and are oriented/point perpendicularly to the axis 10a of the transmission. The magnitudes of the angles (32 and [31 enclosed by the opposite directional axes (23'b, 23'd) and (23'a, 23'c) are different from zero and 180°, respectively. The above applies equally to the magnitudes of the angles enclosed by the directional axes (23b, 23d) and (23a, 23c) on the complementary profiles of the outlet section 20 - Fig.10. The directional axes characterize the complementary profiles of the flange connection 20, 20'. The directional axes (23a, 23'a), (23b, 23'b), (23c, 23'c), (23d, 23'd) intersect the axis 10a perpendicularly.

In a projection onto a plane perpendicular to the axis (10a), for example onto the surface (25) - Fig.7, the direction axes (23'a), (23'c) of the opposite complementary profiles (24'a), (24'c) are non-parallel and at the same time in the projection into the same plane the direction axes (23'b) and (23'd) of the opposite profiles (24'b) and (24'd) are also non-parallel - the angle [31 and the angle [32 are greater than 0 and different from 180°. The reciprocity of the contact profiles refers to the axis (20 'a) of the flange part (20'). The same is the case for the reciprocity of the contact profiles of the flange part (20).

The advantage of the subject invention over the state of the art is that in the state of free contact connection (without the presence of the fasteners (70) - Fig.6 of the complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd), remove three degrees of freedom from the mutual movement of the output parts (20), (20') in the plane perpendicular to the axis (10a), that is the output parts (20), (20') are not free to move relative to each other in the radial direction, nor are they free to rotate relative to each other about the axis (10a). By removing the translational degrees of freedom in the plane perpendicular to the axis (10a), (i) there is no relative positional creep of the parts (20), (20') leading to a change in the prescribed internal position of the transmission components and to vibrations in the power transmission, (ii) there is no asymmetric wear of the transmission components and no premature loss of its parameters. By removing the third degree of freedom around the axis (10a) in the state of free contact coupling (without the presence of coupling elements (70) - Fig.6), there is no change in the mutual axial position of the working surfaces (243a, 243'a), (243b, 243'b), (243c, 243'c), (243d, 243'd) under the mutual torsional loading of the output parts (20), (20'). When the output parts (20), (20') are loaded torsionally against each other in the operating state, no additional axial force is generated in the connecting elements (70), which brings numerous advantages related to the capacity and loadability of the connection of the output parts (20), (20').

The object of the invention is also a force-locking connection of the output parts (20), (20') mutually immovably connectable by pairs of shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd) on opposite pairs of axially oriented longitudinal parts (22a,22'a), (22b, 22'b), (22c,22'c), (22d,22'd) - Fig.12. The forcelocking connection removes the output parts (20), (20') from each other by three degrees of freedom so that one of the output parts (20), (20') cannot rotate relative to the other around the axis (10a), nor can one of the output parts (20), (20') move rela- tive to the other in the radial direction, i.e. in the direction perpendicular to the axis (10a). A precondition for the mutual immobility of the output members (20), (20') in the case of a force-locking connection is a sufficiently large force action in the connecting members (70) with respect to the resulting externally induced axial force acting between the members (20), (20') and with respect to the axial resultant of the decomposition of the internal forces in the complementary profiles.

The complementary profiles of the flange part (20) are determined by the directional axes (23a), (23b), (23c), (23d), the complementary profiles of the flange part (20') are determined by the axes (23'a), (23'b), (23'c), (23'd) - Fig.12, Fig.15, Fig.16. The directional axes lie on the contacting working surfaces whose normal forces act in the circumferential direction with respect to axis (10a). The directional axes are simultaneously oriented transversely to the axis (10a) of the body (10). In a projection onto a plane perpendicular to the axis (10a), for example onto the surface (25') of the outlet part (20'), the directional axes (23'a), (23'c) of the complementary profiles (24 'a), (24 'c) opposite to each other with respect to the axis (20'a) are nonparallel and at the same time, in the projection to the same plane (25'), the directional axes (23'b) and (23'd) of the profiles (24'b) and (24'd) are differently parallel - Fig.15. Also in this case, the reciprocity of the complementary profiles is related to the axis (20'a) of the output part (20'). The above also applies in the case of complementary profiles and their directional axes on the output part (20) - Fig.16. The advantages of a force-locking connection of the output parts of the output body are the same as in the case of a shape-locking connection of the output parts.

LIST OF REFERENCE SYMBOLS

First arm

1s Input space of first arm

2 Second arm

2s Output space of second arm

3 Transmission

4 Motor winding

4r Motor rotor 5 Angular encoder 5o Rotatable part of angular encoder 6 Brake 6o Clamping part of brake

7 Means for transferring energy and control signals

71 Guidance guard

10 Base body

10a Axis 10k Peripheral cavity 10s Clamping fastener 10p Heel portion of the base body (10)

10u

Interface plane

11 Inner toothing of base body (10)

13 Seals

20o Output body

20, 20' Output parts

20a, 20'a Axis of the transformation member 30 in 20, 20'

21 a, 21'a Inner guiding surface on members 20, 20'

22a, 22b; 22c, 22d, 22'a, 'b, 22'd, Axially oriented lugs on 20,20' members 'c

23a, 23b, 23c, 23d, 23'a, 23'b, Directional axes of shape complementary profiles

23'c, 'd

24a, 24'a, 24b, 24'b, 24c, 24'c, Couples Shape complementary contact

24d, 24'd profiles

243a, 243b, 243c, 243d, 243'a, Work surfaces

243'b, 243'c,

243'd

Surfaces with holes for fasteners (70)

242a, 242b, 242c, 242d, 242'a,

242'b, 'c,

242'd Third surfaces

241 a, 241 b, 241 c, 241 d, 241 'a,

241 'b, 241'c,

241 'd

25, 25' Surface area of member (20), (20')

26 Longitudinal recessing Transformation body, transformation element

Arm of transformation body (30) a, 30b Guiding surfaces of transformation body (30)

Rolling elements

Circular bore of rolling element (31 )

Inner cylindrical surface, cylindrical surface, inner cylindrical surface, central hole a Linear guideways of transformation member (30)

Pins

Profile portions on transformation member (30)

Side of tetragon

Linear outlet of profile portion (37) a Axial guiding face on centric part of 56r, 35I Recesses on the transformation member (30) es

Profile parts of transformation member (30)

Sides of the tetragonal base of a member (30)

Gear wheel a Gear axle (40)

External gearing

Peripheral wheel opening

Shaft a Central axis of shaft (50) o Outer cylindrical surface

Eccentric parts of the input shaft ,55 Rolling elements on shaft (50)

Centric part between eccentrics a Rolling body axis -21 , 54-22 Cylinder faces (54)

Rolling elements of the eccentric part (51 )

Shaft centre section (50)

Rolling elements on the centric part (57)

Slow-speed bearing

Connecting member 80 Bearing ring (60)

80a Rolling Body Guideway (92)

81 Bearing track for ball body (91)

90 Slow-moving bearing envelope (60)

91 ,92 Slow Rolling Bearing Rolling Bodies (60) b Shortest distance of profiles (37) and member (30) w Distance of the guiding surfaces (34a) of the

W member (30) Size of the side of the tetragonal e base of the member (30)

Eccentricity

(na, nb, nc, nd, n'a, n'b, Normal vector work surfaces n'c, 'd) Angles of directional axes of contact profiles

[31 , |32 a1 , a2 Angles of normal vectors to Transit hub of means (7)

Claims

1. A device, in particular robot joint, with first arm (1), with second arm(2), with base body (10) and with conductors (7) passing from the first arm (1 ) to the second arm (2) characterized in, that the conductors (7) are at least partially positioned along the periphery of the base body (10).

2. A robot joint according to claim 1 with the base body (10) rotatably supporting the output body (20o) of the transmission (3) with two mutually connectable output parts (20,20') rotatably supporting input shaft (50) having two eccentric parts with external gears (40), which have an outer cycloidal toothing (41 ) meshing with inner toothing (11 ) of the base body (10), with a transformation body (30) to transform planetary motion of external gear (40) into rotary motion of output parts (20,20') characterised in that the first arm (1 ) is toughly connected to the base body (10) while the second arm (2) is toughly connected to the output parts (20,20'), the conductors (7) swivel synchronously with the second arm (2) over the periphery of base body (10), or are on the periphery stationary.

3. The robot joint according to claim 2 characterised in that the rotor (4r) of motor (4), the rotatable part (5o) of angular encoder (5) are coaxially connected to the input shaft (50).

4. The robot joint according to claim 2, characterized in that the rotor (4r) of motor (4), the rotatable part (5o) of angular encoder (5) and the clamping part (6o) of brake (6) are coaxially linkable to the shaft (50) via the shaft extensions (50a), (50b), second angular encoder may be placed in the robot joint coaxially to axis (10a) to identify angular position of first arm (1 ) with respect to the second arm (2). The robot joint according to claim 2, characterized in that the motor winding (4) and the parts of the angular encoder

(5) and the brake (6) stationary to second arm (2) are coaxially and non-rotatably connected to said second arm (2) of the robot joint,

6. The robot joint according to claim 1 characterized in, that the conductors (7) are positioned in a cavity (10k) formed on outer periphery of the base body (10), said cavity (10k) is advantageously of rectangular, or oval like cross-section.

7. The robot joint according to claim 1 characterized in that said conductors (7) are positioned in the cavity (10k) via a guidance guard (71 ), wherein the conductors (7) get out from the periphery space of the base body (10) and enter the output space (2s) of the second arm (2) through a transit hub (to).

8. Robot joint according to claim 2, characterized in that there are seals (13) between the output parts (20), (20') and the base body (10).

9. Robot joint according to claim 2, characterized in that the second arm (2) of the robot joint is coaxially mounted in the outlet portions (20), (20') via centering bodies (20c), annular in shape and having seals (50t) mounted on the inner circumference.

10. Robot joint according to claim 2, characterized in that the base body (10) has a heel portions (1 Op) to which the first arm (1 ) of the robot joint is connected.

11 . The robot joint according to claim 2, characterized in that the rolling bodies (54) on the eccentric portions (51 ) of the input shaft (50) are axially guided by adjacent front surface of the transformation member (30).

12. The robot joint of claim 2, characterized in that the cylindrical rolling bodies (55) on the centric portions of the shaft (50) are axially guided by the adjacent face of the transforming member (30).

13. The robot joint according to claim 2, characterized in that the internal ttothing (11 ) comprises longitudinal pins of even number N, the pins are cylindrical in shape with an individual spacing approximately equal to or less than twice the diameter of the longitudinal pins, wherein the gear ratio i of the transmission is equal to 2N-1 .

14. Transmission according to claim 2, characterized in that the transformation member (30) has the shape of a plate with a tetragonal base, with central opening (33), with linear guideways (34a) lateral to the vertices of the tetragonal base, mutually opposite, parallel to each other and spaced apart from each other by an offset (w), wherein the ratio of the offset (w) of the linear guiding surfaces (34a) to double of diameter of the rolling elements (31 ) is less than 1 .

15. Transmission according to claim 14, characterized in that on the guiding surfaces (34a) there are cylindrical bodies (31 ) having a diameter greater than the length of the guiding surfaces (34a), said guiding surfaces (34a) terminate at the profile portions (37) wherein the shortest distance (b) of opposite profile portions (37) is less than or equal to the perpendicular offset (w) of the guiding surfaces (34a).

16. Transmission according to claim 14, characterized in that the rolling bodies (31 ) have a central circular bore (32) for the cylindrical pins (36), the diameter of the bore (32) and the diameter of the pin (36) being (approximately) the same, on at least one of the flanges (20), (20') and the external gear (40) adjacent thereto, there are longitudinal recesses (26) between the guideways (34a) in which the pins (36) are slidably guided and which limit the positional creep of the rolling bodies (31 ) at their ends.

17. The transmission according to claim 2, characterized in that the shape-locking connection of the output portions (20), (20') have axially oriented pairs longitudinal portions (22a, 22'a), (22b, 22'b), (22c, 22c), (22d,22'd ) on which there are pairs of shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd), wherein the directional axes (23a, 23c), (23b, 23d) and (23'a, (23'c), (23'b, 23'd) of the shape-complementary profiles opposite with respect to the axes (20a), (20'a) are non-parallel/non-colinear in the projection onto a plane perpendicular to the axis (10a).

18. Transmission according to claim 17 characterized in that the normal vectors (na, nc), (nb, nd), (n'a, n'c), (n'b, n'd) of the planar working surfaces (243a, 243c), (243b, 243d) and (243'a, 243'c), (243'b, 243'd) on shape complementary profiles (24a), (24c), (24b), (24d) and (24'a), (24'c), (24'b), (24'd) are oriented perpendicularly to axis (10a), where the pairs of normal vectors (na, nc), (nb, nd) opposite with respect to the axis (20a) enclose angles (02, a 1) different from zero and different from 180° , respectively, and the pairs of normal vectors (n'a, n'c), (n'b, n'd) opposite with respect to the axis (20'a) enclose angles (02, a 1) different from zero and different from 180.

19. Transmission according to claim 17, characterized in that the mutual contact position of the pairs of shape complementary profiles (24a, 24 'a), (24b, 24'b), (24c, 24 'c), (24d, 24 'd) axially force-free connected removes three degrees of freedom of the output part (20) with respect to the output part (20') in a plane perpendicular to the axis (10a).

20. Transmission according to claim 17, characterized in that the mutually contact position of the pairs of shape complementary profiles (24a, 24 'a), (24b, 24'b), (24c, 24'c), (24d, 24'd) in the working state is ensured by the screws (70).

21. Transmission according to claim 17, characterized in that the directional axes (23a), (23b), (23c), (23d) and (23'a), (23'b), (23'c), (23'd) of the shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd) pass perpendicularly through the axis (10a).

22. Transmission according to claim 17, characterized in that on the opposite pairs of shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd) there are surfaces with holes (242a, 242 'a), (242b, 242 'b), (242c, 242 'c), (242d, 242'd) for the connecting elements (70), which are contactable in the working condition of the transmission.

23. The transmission according to claim 2, with a force-locking connection of the output parts (20), (20'), with axially oriented portions (22a), (22b), (22c), (22d ) and (22'a), (22'b), (22'c), (22'd), on which there are pairs of shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd), wherein the directional axes (23a, 23'a), (23b, 23'b) and (23b, 23'b), (23c, 23'c) of the complementary profiles opposite to each other with respect to the axis (20a), (20'a) are non-parallel/non- colinear in projection to a plane perpendicular to the axis (10a).

24. The transmission according to claim 17 or 23 characterized in that the directional axes (23a, 23'a), (23b, 23'b) and (23b, 23'b), (23c, 23'c) of the shape complementary profiles (24a, 24'a), (24b, 24'b), (24c, 24'c), (24d, 24'd) pass perpendicularly through the axis (10a).