Transmission assembly and robot with transmission assembly

Abstract

To provide a transmission assembly and a robot with the transmission assembly.SOLUTION: There is provided a transmission assembly comprising: a driving body with driving-side drums (20, 22) arranged rotatably about a driving axis (18); a driven body with driven-side drums (28, 30) arranged rotatably about a driven axis (26); ropes (32, 38), which can be wound respectively on the driving-side drums (20, 22) and the driven-side drums (28, 30), and include driving-side rope ends (34, 40) and driven-side rope ends (36, 42). Therein, the driving-side rope ends (34, 40) are arranged on the at least one driving-side drum (20, 22), and the driven-side rope ends (36, 42) are arranged on the driven-side drums (28, 30). There is also provided a robot with the transmission assembly.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a transmission assembly and a robot equipped with a transmission assembly. [Background technology]

[0002] Various cross-gear concepts for changing the orientation of a rotation axis in a mechanical drive train are known, which include, inter alia, bevel gear stages and belt drives.

[0003] Bevel gear stages are a widespread transmission concept for changing the orientation of rotational axes, especially in robotics. In particular, they are used to drive the axes of articulated arm robots. However, they are heavy and have play, disadvantageous properties that they share with other gear transmissions.

[0004] In belt transmissions, belts with trapezoidal cross-sections are often used. In belt transmissions, therefore, in order to change the orientation of the rotation axis, it is usually necessary to rotate the belt partially about its longitudinal axis. Such a rotation of the belt requires a free portion of the belt section through which the rotation takes place, and a correspondingly large center distance must be realized. Orthogonal transmissions based on belt transmissions therefore require a relatively large installation space. Furthermore, belt transmissions have a relatively low stiffness compared to alternative transmission concepts. These disadvantages make the devices unattractive, in particular for use in robotics. Summary of the Invention [Problem to be solved by the invention]

[0005] The invention is based on the problem of providing a transmission assembly which is suitable for changing the orientation of the rotation axis, has high rigidity, requires little space and at the same time is free of play and has low weight. Furthermore, the transmission assembly should be cheap and easy to manufacture.

[0006] The invention is further based on the object of providing a robot which is able to perform highly dynamic movements and at the same time requires little space and is cheap and easy to manufacture. [Means for solving the problem]

[0007] The above object is achieved according to the invention by a transmission assembly having the features of claim 1 and by a robot having the features of claim 16. Advantageous embodiments and developments of the invention are set forth in the dependent claims.

[0008] The transmission according to the present invention comprises a driver having at least one driving drum rotatably arranged about a drive shaft, and a driven body having at least one driven drum rotatably arranged about a driven shaft. The transmission assembly further comprises at least one rope that can be wound around the at least one driving drum and the at least one driven drum and has a driving rope end and a driven rope end. The driving rope end is disposed on the at least one driving drum and the driven rope end is disposed on the at least one driven drum.

[0009] Thus, by rotating the at least one driving drum about the driving axis, the speed and the torque can be transmitted to the at least one driven drum via the at least one rope. In the present description, a drum is understood in the following to mean a body having, in particular, a cylindrical basic shape. However, the drum can also be formed by a further body provided and / or suitable for winding the at least one rope and rotatable about its longitudinal axis. In that case, the rotation angle of the at least one driving drum and the at least one driven drum can be limited in particular by the length of the at least one rope. In the present description and in the following, a rope is understood in particular to mean a structure capable of carrying a tensile load, in particular elongated, which, unlike a belt, has a substantially round cross section. Thus, a rotation of the at least one rope, in particular for changing the orientation of the rotation axis, can be omitted. Furthermore, the rope can have a particularly high stiffness.

[0010] The transmission ratio of the transmission assembly can be formed by the quotient of the diameter of the at least one driven drum and the diameter of the at least one driving drum. The maximum rotation angle of the at least one driven drum can depend, in particular, on the transmission ratio, in addition to the length of the at least one rope. Thus, when the transmission ratio is 1, the maximum rotation angle of the at least one driven drum is in particular 360°. When the transmission ratio is 2, the maximum rotation angle of the at least one driven drum can be, for example, 180°.

[0011] In particular, the driver can be rotatable together with the at least one driving drum about a drive axis. Correspondingly, the driven body can also be rotatable together with the at least one driven drum about a driven axis. The driver and / or the driven body can in particular be formed as a wheel.

[0012] To return the transmission assembly, the transmission assembly can, for example, include a spring element, which is pretensioned by the at least one driving drum when introducing a speed and a torque into the transmission assembly. In particular, the at least one driven drum can be supported against the spring element.

[0013] In particular, at least one rope simultaneously abuts on at least one driving drum and at least one driven drum by a contact circumference. This allows at least one driving drum and at least one driven drum to be arranged very close together. This allows the installation space required by the transmission assembly to be reduced. The contact circumference is to be understood as the imaginary circumference of the rope in its position relative to the rope centerline. The contact circumference can indicate the turning point of at least one rope abutting on at least one driving drum and at least one driven drum. For the drums involved, the imaginary tangent of the at least one driving drum arranged on the rope centerline and the imaginary tangent of the at least one driven drum arranged on the rope centerline can coincide at the position of the contact circumference.

[0014] The transmission assembly may also have a contact area associated with the rope centerline, in which at least one rope simultaneously abuts against at least one driving drum and at least one driven drum, the contact area being defined on the one hand by a first contact circumference and on the other hand by a second contact circumference. The contact area may be formed in particular by elastic deformation of the components involved.

[0015] The drive shaft and the driven shaft can have an angular offset from one another, so that the gear assembly can realize a change in the orientation of the rotation axis in the smallest possible installation space. In particular, the drive shaft and the driven shaft intersect at a common axis intersection. The angular offset between the drive shaft and the driven shaft is 90°.

[0016] The drive rope end can be arranged on at least one drive drum and / or the driven rope end can be arranged on at least one driven drum. This allows the realization of a transmission assembly with at least one end as well as two rope ends. In particular, the use of an endless rope, i.e. one closed rope, can be omitted. Furthermore, the external and internal friction losses of the at least one rope can be reduced. Preferably, each rope end is screwed to at least one drive drum and / or to at least one driven drum.

[0017] In particular, the at least one driving drum and / or the at least one driven drum have a circumferentially extending groove for receiving at least one rope. The groove can thus form an interface between the at least one driving drum and / or the at least one driven drum and the at least one rope. The groove can receive the at least one rope on a defined circumference of the at least one driving drum and / or the at least one driven drum. This ensures a reliable transmission of speed and torque. The groove preferably has an arcuate profile in cross section. The groove can thus have an opening. Particularly preferably, the arcuate profile has a constant radius, whereby the profile is formed in the shape of a circular arc. This allows the groove to be particularly well adapted to the profile of the at least one rope. If a groove is used for receiving the at least one rope, the transmission ratio of the transmission assembly is determined in particular by the diameter ratio of the at least one driven drum and the at least one driving drum.

[0018] In one development of the invention, the groove is formed helically on at least one of the at least one driving drum and / or the at least one driven drum, whereby a maximum rotation angle of the drum with the helical groove of more than 360° can be achieved. In particular, the opening of the groove is arranged perpendicular to the rotation axis of the corresponding drum, so that at least one rope can be inserted into and removed from the groove perpendicular to the rotation axis of the corresponding drum. Thus, if a helical groove is arranged on the driving drum, the opening of the groove is oriented in particular perpendicular to the drive axis.

[0019] In one embodiment of the invention, the at least one driving drum is arranged so that it can be axially displaced as a function of the driving rotation angle and / or the at least one driven drum as a function of the driven rotation angle. In that case, in particular the rotation angle of the driving drum is called the driving rotation angle. Correspondingly, the rotation angle of the driven drum can be called the driven rotation angle. Such a dependency allows the movement of the at least one rope from the at least one driving drum to the at least one driven drum and vice versa while maintaining the aforementioned contact circumference, in particular in the case of a helical groove. The axial displaceability of the at least one driving drum is provided in particular so that it can be displaced along the drive axis. The axial displaceability of the at least one driven drum is provided in particular so that it can be displaced along the driven axis. The axial displaceability of the at least one driving drum and / or the at least one driven drum can be realized, for example, by a screw guide.

[0020] To further ensure a smooth movement of the at least one rope from the at least one driving drum to the at least one driven drum and vice versa, a roller-like pressure holding device can be arranged on the at least one driven drum and / or on the at least one driving drum, which can position the at least one rope on the at least one driven drum and / or on the at least one driving drum.

[0021] A tensioning device for tensioning the at least one rope can be arranged on the driver and / or the driven body. This allows the pretension of the at least one rope and therefore in particular the stiffness and play of the transmission assembly to be adjusted. In particular, the tensioning device is arranged in a groove. It is particularly preferred that the tensioning device is arranged on the at least one driven drum. The tensioning device can have a tensioning screw for tensioning the at least one rope. Alternatively, the tensioning device can be integrated into the at least one rope.

[0022] In one development of the invention, the transmission assembly has a deflector which comprises at least one deflecting drum which is rotatable about a deflection axis. The deflector is in particular arranged in such a way that at least one rope simultaneously abuts against at least one deflecting drum and at least one driving drum or against at least one deflecting drum and at least one driven drum by means of a contact circumference. Such a deflector can increase many times the possibilities for arranging the driving body and the driven body relative to each other in space. In particular, the deflector can allow for an arrangement of the driving body and the driven body which are spatially separated from each other. Furthermore, the deflector can form an additional transmission stage, which can allow for an increase in the transmission ratio of the transmission assembly. If the driving shaft and the driven shaft have an angular offset from each other, a corresponding deflection of the rope can be performed by the deflector. The deflector axis can form a deflection angle with the driving shaft and / or with the driven shaft.

[0023] In a preferred embodiment of the present invention, the driver has a first driving drum and a second driving drum, each corresponding to the at least one driving drum, and the driven body has a first driven drum and a second driven drum, each corresponding to the at least one driven drum. Thus, the first driving drum and the second driving drum can be arranged to be rotatable about a drive shaft, and the first driven drum and the second driven drum can be arranged to be rotatable about a driven shaft, respectively.

[0024] Furthermore, in this embodiment, the transmission assembly comprises a first rope corresponding to at least one rope and a second rope corresponding to at least one rope, the first rope being operatively connected to the first drum and the second rope being operatively connected to the second drum. Thus, in particular, the first rope can be wound around the first driving drum and the first driven drum and has a first driving rope end and a first driven rope end, the first driving rope end can be arranged on the first driving drum and the first driven rope end can be arranged on the first driven drum. Correspondingly, the second rope can be wound around the second driving drum and the second driven drum and has a second driving rope end and a second driven rope end, the second driving rope end can be arranged on the second driving drum and the second driven rope end can be arranged on the second driven drum.

[0025] The first driving drum and the second driving drum are each connected to at least one of the driving drums. The first driven drum and the second driven drum are each connected to at least one of the driven drums. and The first rope and the second rope are each connected to at least one of the aforementioned ropes. Correspondingly, in that case, the first rope is operatively connected to the first drum and the second rope is operatively connected to the second drum, so that the transmission assembly can have the features particularly described below.

[0026] The first rope can simultaneously abut the first driving drum and the first driven drum with a first contact circumference, and the second rope can simultaneously abut the second driving drum and the second driven drum with a second contact circumference. Accordingly, the transmission assembly can have a first contact area and a second contact area.

[0027] In particular, the first drive rope end is attached to the first drive drum and / or the first driven rope end to the first driven drum in a positive, frictional and / or material-locking manner, and thus in particular the second drive rope end is attached to the second drive drum and / or the second driven rope end to the second driven drum in a positive, frictional and / or material-locking manner.

[0028] The first driving drum and / or the first driven drum may each have a circumferentially extending groove for receiving the first rope. The second driving drum and / or the second driven drum may each have a circumferentially extending groove for receiving the second rope. One or more of the grooves may be formed helically.

[0029] The first driving side drum and / or the second driving side drum may be arranged so as to be displaceable in the axial direction according to a driving side rotation angle. The first driven side drum and / or the second driven side drum may be arranged so as to be displaceable in the axial direction according to a driven side rotation angle.

[0030] It is particularly preferred that the tensioning device is arranged on at least one driven drum. The first driving drum can have a first driving tension device and the second driving drum can have a second driving tension device, in particular the first driven drum is arranged with a first driven tension device and the second driven drum is arranged with a second driven tension device.

[0031] The deflector may have a first deflection drum and a second deflection drum, where the first deflection drum may be arranged such that the first rope is in contact with the first deflection drum and the first driving drum or the first deflection drum and the first driven drum simultaneously with a first contact circumference, and the second deflection drum may be arranged accordingly such that the second rope is in contact with the second deflection drum and the second driving drum or the second deflection drum and the second driven drum simultaneously with a second contact circumference.

[0032] Furthermore, the invention provides that at least one of the second drums is arranged axially offset with respect to the corresponding first drum and / or that at least one of the second drums is formed with a different, in particular smaller, diameter than the corresponding first drum. In that case, the axial offset is in particular related to the corresponding rotation axis. For example, the second driving drum can be arranged axially offset with respect to the driving axis with respect to the first driving drum. The same applies for the driven drum associated with the driven shaft and / or the deflecting drum associated with the deflecting shaft. With such an arrangement, a contact-free crossing of the first and second ropes can be achieved, in particular if the corresponding rotation axes are angularly offset. Mutual friction between the first and second ropes can thereby be avoided. In particular if the involved rotation axes are angularly offset, the openings of the grooves arranged on the respective drums are in particular inclined with respect to the corresponding rotation axes. If the angular offset of the driven shaft with respect to the drive shaft is, for example, 90°, the groove openings of the first and second driving drums can each be inclined, in particular, by 45° with respect to the drive shaft. In this case, the same can be true for the groove openings of the driven drums associated with the driven shaft. If the diameter of the involved second drum is different from the diameter of the involved second drum, the diameter ratio of the involved first drum and the involved second drum is in particular constant. As a result, the involved first drum and the involved second drum can have the same transmission ratio. This makes it possible to avoid misalignment of the transmission assembly.

[0033] In particular, the first and second ropes are arranged in opposite directions with respect to the drive shaft at the driver and / or with respect to the driven shaft at the driven body, so that opposite rotational speeds and torques can be transmitted by the first and second ropes, and thus return spring elements can be omitted.

[0034] The driving drum and / or the driven drum can be arranged so that they can rotate relative to one another. For this purpose, two driving drums and / or two driven drums can each be connected to one another by means of an adjusting screw. This allows the first rope and the second rope to be pretensioned relative to one another. The rotatability of the driving drum and / or the driven drum relative to one another can therefore be an alternative to the tensioning device described above. The rotation of the driving drum is in particular about a driving shaft. The rotation of the driven drum is in particular about a driven shaft. Particularly preferably, the driving drum and / or the driven drum are each arranged so that they can be locked relative to one another.

[0035] In one development of the invention, the first and second driving drums are arranged offset by 180° relative to one another with respect to the driven shaft and / or the first and second driven drums are arranged offset by 180° relative to one another with respect to the drive shaft, thereby making it possible to adapt the installation space required, in particular, by the transmission assembly. Such an arrangement of the driving drums makes it possible to realize an offset of 180° relative to the driven shaft between the first transfer point, at which the first rope is transferred from the first driving drum to the first driven drum, and the second transfer point, at which the second rope is transferred from the second driving drum to the second driven drum. Accordingly, such an arrangement of the driven drums makes it possible to realize an offset of 180° relative to the drive shaft between the first transfer point and the second transfer point. Such an offset arrangement of the driving drums is used in particular when the grooves arranged on the driving drums are formed in a spiral shape. Such an offset arrangement of the driven drum is used in particular when the grooves arranged on the driven drum are formed in a spiral shape. Installation space advantages can be achieved by such an offset arrangement of the driving or driven drum, especially when the angular offset between the driving and driven shafts is 90°. The 180° offset drums are arranged on a common shaft that intersects with the driving or driven shaft, especially when the angular offset between the driving and driven shafts is 90°.

[0036] If the transmission assembly comprises a deflection body, the first driving drum and the second driving drum can be arranged offset by 180° from each other in relation to the deflection axis and / or the first driven drum and the second driven drum can be arranged offset by 180° from each other in relation to the deflection axis, in particular when the drive shaft and the deflection axis and / or the driven shaft and the deflection axis are arranged offset by 90° from each other.

[0037] In another embodiment of the invention, the driver is arranged between the first and second driven drums with respect to the drive shaft, and / or the driven drum is arranged between the first and second driving drums with respect to the driven shaft. With such an arrangement, installation space advantages can also be achieved. This arrangement is used in particular when the grooves arranged on the driver drum and / or on the driven drum are formed helically and / or the drive shaft and the driven shaft have an angular offset from one another, in particular of 90°. In that case, the drum of the driver can be arranged on the opposite side of the driver with respect to the drive shaft. In that case, the drum of the driven drum can be arranged on the opposite side of the driven drum with respect to the driven shaft.

[0038] Accordingly, the deflector may be arranged between the first driven drum and the second driven drum in relation to the deflection axis and / or between the first driving drum and the second driving drum.

[0039] The robot according to the invention comprises a transmission assembly having the above-mentioned characteristics. The robot may comprise a base and a robot arm having a first arm part and a second arm part, the second arm part being arranged on the first arm part rotatably around a first joint axis. The first arm part may be arranged on a base. The base may support the robot arm with respect to the environment. The driver may be arranged on the first arm part. In particular, a drive unit for driving the driver may be further arranged on the first arm part. The follower may be arranged on the second arm part such that the driven axis lies on the first joint axis. To transmit the rotational speed and the torque from the drive unit to the follower, the follower may be arranged such that the first and second ropes simultaneously abut the corresponding driving drum and the corresponding driven drum with a first and a second contact circumference. The driving and driven axes may have an offset of 90° from each other. Such an arrangement allows a relatively heavy drive unit to be placed in the first arm section near the base, while the second arm section can have a relatively small weight, thus enhancing the dynamics of the robot. Furthermore, the installation space required by the robot arm can be significantly reduced.

[0040] In one development, the robot has a third arm part, which is arranged on the second arm part rotatably about the second joint axis. The second drive unit can be arranged on the second arm part, in particular near the first joint axis. The robot can comprise a second transmission assembly having the above-mentioned features, which includes a deflector. The driver of the second transmission assembly is arranged on the second drive unit, in particular on the second arm part. The driven body of the second transmission assembly can be arranged on the third arm part such that the driven shaft of the second transmission assembly lies on the second joint axis. For transmitting the speed and the torque from the second drive unit to the driven body of the second transmission assembly, the deflector can be arranged such that the first rope and the second rope of the second transmission assembly simultaneously abut on the deflector drum and the drive drum of the second transmission assembly by means of a contact circumference. The deflector can further be arranged such that the deflector shaft lies on the first joint axis. In that case, the drive shaft of the second transmission assembly and the deflection shaft of the second transmission assembly can have an offset of 90° from each other, thereby simultaneously reducing the installation space and further increasing the dynamics of the robot. By having a deflector in the second transmission assembly, the second transmission assembly can bridge the length of the second arm portion between the driver and the associated driven member of the second transmission assembly.

[0041] An embodiment of the present invention will be described with reference to the following figures. [Brief description of the drawings]

[0042] [Figure 1] FIG. 1A is a partial view of a robot arm equipped with a transmission assembly according to the prior art, and FIG. 1B is a partial view of a robot arm according to a first embodiment of the transmission assembly according to the present invention. [Diagram 2] 1 is a perspective view of a first embodiment of a transmission assembly according to the present invention; [Diagram 3] FIG. 3 is an exploded view of the embodiment shown in FIG. 2. [Figure 4]FIG. 3 is a cross-sectional view of the embodiment shown in FIG. [Diagram 5] FIG. 3 is a rear partial view of the embodiment shown in FIG. 2 with an adjustment screw. [Figure 6] FIG. 4 is a partial view of a second embodiment of a transmission assembly according to the invention, comprising a tensioning device; [Figure 7] FIG. 11 is a perspective view of a third embodiment of a transmission assembly according to the present invention; [Figure 8] FIG. 13 is a perspective view of a fourth embodiment of a transmission assembly according to the present invention; [Figure 9] FIG. 13 is a perspective view of a fifth embodiment of a transmission assembly according to the present invention; [Figure 10] FIG. 10 is a cross-sectional view of the embodiment shown in FIG. [Figure 11] FIG. 13 is a perspective view of a sixth embodiment of a transmission assembly according to the present invention; [Figure 12] FIG. 12 is a cross-sectional view of the embodiment shown in FIG. [Figure 13] 1 is a cross-sectional view of an embodiment of a robot according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] 1(b) to 13 show various views of various embodiments. The same reference symbols are used for the same and functionally the same parts. For clarity, the reference symbols are not used in all the views.

[0044] Figure 1(a) shows a partial view of a robot arm 200 with a prior art gearing assembly 202. The gearing assembly includes bevel gears 204 and is therefore relatively heavy and has play.

[0045] Figure 1(b) contrasts a partial view of the prior art robot arm 200 shown in Figure 1(a) with a robot arm 10 of a robot 12 according to the invention with a first embodiment of a gearing assembly 14 according to the invention. The gearing assembly 14 is relatively light and without play.

[0046] A first embodiment of the transmission assembly 14 is shown in detail in Figs. 2 to 5. The transmission assembly 14 comprises a driver 16 and a drive shaft 18. The driver 16 may have a first drive drum 20 rotatably arranged about the drive shaft 18 and a second drive drum 22 rotatably arranged about the drive shaft 18. In addition, the transmission assembly also comprises a driven body 24 and a driven shaft 26. The driven body 24 may have a first driven drum 28 rotatably arranged about the driven shaft 26 and a second driven drum 30 rotatably arranged about the driven shaft 26. In particular, the drive shaft 18 and the driven shaft 26 intersect at a common axis intersection 31. Particularly preferably, the interaxial offset 31a of the angle between the drive shaft and the driven shaft is 90°.

[0047] Additionally, the transmission assembly 14 may include a first rope 32 that may be wrapped around the first driving drum 20 and the first driven drum 28 and that has a first driving rope end 34 and a first driven rope end 36. Specifically, the first driving rope end 34 is disposed on the first driving drum 20 and the first driven rope end 36 is disposed on the first driven drum 28. Additionally, the transmission assembly 14 may include a second rope 38 that may be wrapped around the second driving drum 22 and the second driven drum 30 and that has a second driving rope end 40 and a second driven end 42. Specifically, the second driving rope end 40 is disposed on the second driving drum 22 and the second driven rope end 42 is disposed on the second driven drum 30.

[0048] In particular, the first rope 32 and the second rope 38 are arranged in opposite directions with respect to the drive shaft 18 at the driver 16, and are arranged in opposite directions with respect to the driven shaft 26 at the driven body 24. Thus, opposite speeds and torques can be transmitted by the first rope 32 and the second rope 38.

[0049] Thus, by rotating one of the driving drums 20, 22 about the drive shaft 18 in a first rotation direction 44, the rotational speed and torque can be transmitted via the first rope 32 to the first driven drum 28 and thus to the driven body 24. Correspondingly, by rotating one of the driving drums 20, 22 about the drive shaft 18 in a second rotation direction 46, the rotational speed and torque can be transmitted via the second rope 38 to the second driven drum 30 and thus to the driven body 24. The rotational angle of the driving drums 20, 22 and the driven drums 28, 30 can then be limited in particular by the length of the ropes 32, 38.

[0050] The transmission ratio of the transmission assembly 14 can be formed by the quotient of the first driven drum diameter 48 of the first driven drum 28 and the first driving drum diameter 50 of the first driving drum 20. The corresponding quotient of the second driven drum diameter 52 of the second driven drum 30 and the second driving drum diameter 54 of the second driving drum 22 is in particular of the same magnitude. The embodiment shown in Figures 2 to 5 has a transmission ratio of 1. Thus, the maximum driving rotation angle 56 and the maximum driven rotation angle 58 are of the same magnitude and are defined by the length of the ropes 32, 38 as less than 360° in the embodiment shown in Figure 2.

[0051] In particular, the driver 16 can be rotatable about a drive shaft 18 together with the driver drums 20, 22. The driven body 24 can also be rotatable about a driven shaft 26 together with the driven drums 28, 30. The driver 16 and the driven body 24 can be formed as wheels.

[0052] In particular, the first rope 32 shown in Figures 3 and 4 can be brought into contact with the first driving drum 20 and the first driven drum 28 simultaneously by the first contact circumference 60. The second rope 38 can then be brought into contact with the second driving drum 22 and the second driven drum 30 simultaneously by the second contact circumference 62.

[0053] Each contact circumference 60, 62 can indicate a turning point of the corresponding rope 32, 38 abutting against the corresponding driving drum 20, 22 and the corresponding driven drum 28, 30. As shown in FIG. 4 by taking the second drum 22, 30 as an example, a virtual driving tangent 64 of the second driving drum 22, which is disposed on a rope centerline 66 of the second rope 38, and a virtual driven tangent 68 of the second driven drum 30, which is disposed on the rope centerline 66, can coincide at the position of the second contact circumference 62. This relationship applies to the first contact circumference 60 as well.

[0054] As can be seen particularly from FIG. 3, the drive rope ends 34, 40 are positively and frictionally attached to the drive drums 20, 22 and the driven rope ends 36, 42 are positively and frictionally attached to the driven drums 28, 30 by threaded connections 70, respectively.

[0055] As can be seen in particular from the illustration in Fig. 4, the first driving drum 20 and the first driven drum 28, as well as the second driving drum 22 and the second driven drum 30, can each have a circumferentially extending groove 72 for receiving the first rope 32 or the second rope 38. The groove 72 can thus form the interface between the first driving drum 20 or the first driven drum 28 and the first rope 32, and the interface between the second driving drum 22 or the second driven drum 30 and the second rope 38. The groove 72 allows the first rope 32 and the second rope 38 to be received in a defined circumference of the corresponding driving drum 20, 22 and the corresponding driven drum 28, 30. As shown in Fig. 4, the groove 72 has an arcuate contour 74, in particular with a constant radius, whereby the contour 74 is formed in the shape of a circle.

[0056] As can be seen in particular in Figures 2 and 4, the transmission assembly 14 can also be configured in such a way that the second driving drum 22 and the second driven drum 30 are arranged axially offset with respect to the corresponding first drum 20, 28, respectively, and have a smaller diameter than another, in particular the corresponding first drum 20, 28. In that case, the axial offset of the second driving drum 22 and the first driving drum 20 is in particular related to the corresponding rotation axis, i.e. the drive shaft 18. Correspondingly, the axial offset of the second driven drum 30 and the first driven drum 28 is in particular related to the driven shaft 26. With such an arrangement, in particular due to the angular axial offset 31a, a contact-free crossing of the first rope 32 and the second rope 38 can be achieved.

[0057] In the case of an angular inter-axial offset 31a of 90°, the openings 76 of the grooves 72 of the first driving drum 20 and of the second driving drum 22, respectively, can in particular be inclined by 45° with respect to the drive shaft 18. The same then applies for the openings 76 of the grooves 72 of the driven drums 28, 30 with respect to the driven shaft 26.

[0058] The driving drums 20, 22 and / or the driven drums 28, 30 can each be arranged so that they can rotate relative to one another. For this purpose, the two driving drums 20, 22 and / or the two driven drums 28, 30 can each be connected to one another by means of an adjusting screw 78, which is shown in FIG. 5. The adjusting screw 78 is arranged in particular on the rear side of the driver 16 and / or the driven body 24. Thereby, the first rope 32 and the second rope 38 can be pretensioned relative to one another. The rotation of the driving drums 20, 22 is in particular about the drive shaft 18. The rotation of the driven drums 28, 30 is in particular about the driven shaft 26. Particularly preferably, the driving drums 20, 22 and / or the driven drums 28, 30 are also each arranged so that they can be locked relative to one another. The locking can also be performed by means of the adjusting screw 78.

[0059] With regard to the alternative embodiment of the transmission assembly 14 shown in FIGS. 6-12, particular reference will be made to the differences from the first embodiment shown in FIGS. As the partial view from the second embodiment of the transmission assembly 14 shown in Fig. 6 shows, instead of by rotating the driving drums 20, 22 and / or the driven drums 28, 30 relative to each other, the first rope 32 and / or the second rope 38 can be tensioned by means of a tensioning device 80 which can be arranged on the driver 18 and / or the driven drum 24, respectively. In particular, the tensioning device 80 is arranged in the respective groove 72. Particularly preferably, one of the tensioning devices 80 is arranged on the first driven drum 28 and on the second driven drum 30, respectively. The tensioning device 80 can have a tensioning screw 82 for tensioning the respective rope 32, 38.

[0060] FIG. 7 shows a third embodiment of a transmission assembly 14 which substantially corresponds to the first embodiment shown in FIGS. 2 to 5, but which has an angular inter-axis offset 31a which, unlike the first embodiment, is 60°.

[0061] In the fourth embodiment shown in Fig. 8, the transmission assembly 14 has, in addition to the features of the first embodiment of Figs. 2 to 5, a deflection body 84 including, in particular, a first deflection drum 86 and a second deflection drum 88, each of which can be arranged rotatably about a deflection axis 90. The first deflection drum 86 can then be arranged such that the first rope 32 abuts simultaneously against the first deflection drum 86 and the first drive-side drum 20 by the first contact circumference 60. Correspondingly, the second deflection drum 88 can be arranged such that the second rope 38 abuts simultaneously against the second deflection drum 88 and the second drive-side drum 22 by the second contact circumference 62.

[0062] 8, the deflector 84 allows for spatially separated positioning of the driver 16 and driven 24. When the drive shaft 18 and driven shaft 26 have an angular axis offset 31a, a corresponding deflection of the ropes 32, 38 can be achieved by the deflector 84. The deflection axis 90 can form a corresponding deflection angle 92 with the drive shaft 18.

[0063] Depending on the design of the driver 16 and the follower 24, the second deflection drum 88 can be arranged axially offset relative to the first deflection drum 86 with respect to the deflection axis 90. The diameter of the second deflection drum 88 can also differ from the diameter of the first deflection drum 86, in particular the second deflection drum 88 can have a smaller diameter than the first deflection drum 86.

[0064] 9 and 10 show a fifth embodiment of the transmission assembly 14, in which the groove 72 arranged on the first driving drum 20 and on the second driving drum 22 is formed helically, whereby a maximum rotation angle of the driving drums 20, 22 exceeding 360° can be achieved. In particular, the opening 76 of the groove 72 is then arranged perpendicular to the drive shaft 18, so that the first rope 32 and the second rope 38 can be inserted into and removed from the groove 72 perpendicular to the drive shaft 18.

[0065] In the illustrations of Figures 9 and 10, the interaxial offset 31a of the driven shaft 26 relative to the drive shaft 18 is 90°. Furthermore, the first driving drum 20 and the second driving drum 22 are arranged offset from each other by 180° with respect to the driven shaft 26. This arrangement of the driving drums makes it possible to realize an offset of 180° with respect to the driven shaft 26 between the first transfer point 94, at which the first rope 32 is transferred from the first driving drum 20 to the first driven drum 28, and the second transfer point 96, at which the second rope 38 is transferred from the second driving drum 22 to the second driven drum 30. The first driving drum 20 and the second driving drum 22 are arranged on a common drive shaft 98, which in particular intersects with the driven shaft 26.

[0066] As can be seen from the cross-sectional view in FIG. 10, the driving drums 20, 22 can be arranged to be displaceable axially, i.e. along the drive shaft 18, depending on the driving rotation angle. Such a dependency allows the ropes 32, 38 to be moved from the driving drums 20, 22 to the driven drums 28, 30 and vice versa, while maintaining the first and second contact circumferences 60, 62, in particular if the grooves 72 are formed helically. The axial displaceability of the driving drums 20, 22 can be realized by means of a screw guide 100. To further ensure a flawless movement of the ropes 32, 38 from the driving drums 20, 22 to the driven drums 28, 30 and vice versa, a roll-shaped pressure device 102 can be arranged on the first and second driven drums 28, 30, respectively, which can position the first and second ropes 32, 38 on the corresponding driven drums 28, 30.

[0067] The sixth embodiment of the transmission assembly 14 shown in Figures 11 and 12 differs from that shown in Figures 9 and 10, inter alia, in that the follower 24 is arranged with respect to the driven shaft 26, in particular between the first driving side drum 20 and the second driving side drum 22. In that case, the drum of the follower 24 can be arranged on the opposite side of the follower 24 with respect to the drive shaft 26.

[0068] Fig. 13 shows an embodiment of a robot 12 with a transmission assembly 14. The robot 12 may have a base 104 and a robot arm 10 including a first arm portion 106 and a second arm portion 108, the second arm portion 108 being arranged on the first arm portion 106 in particular rotatably about a first joint axis 110. The first arm portion 106 may be arranged on the base 104. The base 104 may support the robot arm 10 with respect to the surrounding environment. A driver 16 may be arranged on the first arm portion 106. In particular, a drive unit 112 for driving the driver 16 is further arranged on the first arm portion 106.

[0069] The follower 24 can be arranged on the second arm part 108 such that the driven shaft 18 is located on the first articulated shaft 110. To transmit rotational speed and torque from the drive unit 112 to the follower 16, the follower 16 can be arranged such that the first rope 32 and the second rope 38 simultaneously abut the corresponding drive drum 20, 22 and the corresponding driven drum 28, 30 by the first contact circumference 60 and the second contact circumference 62. In that case, the drive shaft 18 and the driven shaft 26 can have an inter-axis offset 31a of 90° from each other. Such an arrangement allows the relatively heavy drive unit 112 to be arranged on the first arm part 106 close to the base.

[0070] The robot 12 may have a third arm portion 114 arranged on the second arm portion 108 rotatably about a second joint axis 116. A second drive unit 118 may be arranged on the second arm portion 109, in particular near the first joint axis 110. The robot may have a second transmission assembly 14a including a deflector 84a. A second driver 16a of the second transmission assembly 14a is arranged on the second drive unit 118, in particular on the second arm portion 108. A second follower 24a of the second transmission assembly 14a may be arranged on the third arm portion 114 such that a second follower axis 26a lies on the second joint axis 116. To transmit the rotational speed and torque from the second drive unit 118 to the second driven body 24a, the deflector 84a can be arranged such that the first rope 32a of the second transmission assembly 14a and the second rope 38a of the second transmission assembly 14a simultaneously abut the deflector 84a and the second driven body 16a with corresponding contact circumferences. The deflector 84a can further be arranged such that the deflection axis 90a of the second transmission assembly 14a is located on the first articulation axis 110. In that case, the drive axis 18a and the deflection axis 90a of the second transmission assembly 14a can have an offset of 90° from each other. By having the deflector 84a in the second transmission assembly 14a, the second transmission assembly can bridge the length of the second arm portion 108 between the second driven body 16a and the associated second driven body 24a. [Explanation of symbols]

[0071] 10...robot arm, 12...robot, 14...transmission assembly, 14a...second transmission assembly, 16...driver, 16a...second driver, 18...drive shaft, 18a...drive shaft of second transmission assembly, 20...first drive drum, 22...second drive drum, 24...follower, 24a...second follower, 26...follower shaft, 26a...second follower shaft, 28...first follower drum, 30...second follower drum, 31...axis intersection, 31a...axis offset, 32...first rope, 32a...first rope of second transmission assembly, 34 ...first drive rope end, 36...first driven rope end, 38...second rope, 38a...second rope of second transmission assembly, 40...second drive rope end, 42...second driven rope end, 44...first rotation direction, 46...second rotation direction, 48...first driven drum diameter, 50...first drive drum diameter, 52...second driven drum diameter, 54...second drive drum diameter, 56...maximum drive rotation angle, 58...maximum driven rotation angle, 60...first contact circumference, 62...second contact circumference, 64...drive tangent, 66...rope centerline, 68... Driven side tangent, 70... threaded connection, 72... groove, 74... contour, 76... opening, 78... adjusting screw, 80... tensioning device, 82... tensioning screw, 84... deflection body, 84a... deflection body of second transmission assembly, 86... first deflection drum, 88... second deflection drum, 90... deflection shaft, 90a... Deflection shaft of second transmission assembly, 92...deflection angle, 94...first delivery point, 96...second delivery point, 98...drive shaft, 100...screw guide, 102...holding device, 104...base, 106...first arm portion, 108...second arm portion, 110...first joint shaft, 112...drive unit, 114...third arm portion, 116...second joint shaft, 118...second drive unit, 200...robot arm (prior art), 202...transmission assembly (prior art), 204...bevel gear.

Claims

1. A transmission assembly (14, 14a) having the following features, namely - A drive unit (16, 16a) having at least one drive-side drum (20, 22) rotatably arranged around a drive shaft (18, 18a), - A driven body (24, 24a) having at least one driven drum (28, 30) rotatably arranged around a driven shaft (26, 26a), - comprising at least one rope (32, 38) that can be wound around the at least one drive-side drum (20, 22) and the at least one driven-side drum (28, 30), and having drive-side rope ends (34, 40) and driven-side rope ends (36, 42), In a transmission assembly in which the drive-side rope ends (34, 40) are positioned on at least one drive-side drum (20, 22) and the driven-side rope ends (36, 42) are positioned on at least one driven-side drum (28, 30), A transmission assembly in which at least one drive drum (20, 22) is arranged to be displaceable in the axial direction depending on the drive rotation angle, and / or at least one driven drum (28, 30) is arranged to be displaceable in the axial direction depending on the driven rotation angle.

2. The transmission assembly according to claim 1, wherein at least one rope (32, 38) simultaneously contacts the at least one drive-side drum (20, 22) and the at least one driven-side drum (28, 30) by the contact circumference (60, 62).

3. The transmission assembly according to claim 1, wherein the drive shafts (18, 18a) and the driven shafts (26, 26a) have an angular interaxial offset (31a) from each other.

4. The transmission assembly according to any one of claims 1 to 3, wherein the drive rope ends (34, 40) are attached in a shape-coupled and / or force-coupled manner to the at least one drive drum (20, 22), and / or the driven rope ends (36, 42) are attached in a shape-coupled and / or force-coupled manner to the at least one driven drum (28, 30).

5. The transmission assembly according to any one of claims 1 to 3, wherein the at least one drive drum (20, 22) and / or the at least one driven drum (28, 30) have a circumferentially extending groove (72) for accommodating the at least one rope (32, 38).

6. The transmission assembly according to claim 5, wherein the groove (72) is formed spirally on at least one of the at least one drive drum (20, 22) and / or the at least one driven drum (28, 30).

7. A power transmission assembly according to any one of claims 1 to 3, wherein a tensioning device (80) for applying tension to the at least one rope (32, 38) is provided on the drive body (16, 16a) and / or the driven body (24, 24a).

8. A transmission assembly according to any one of claims 1 to 3, wherein a deflection body (84, 84a) having at least one deflection drum (86, 88) rotatable about a deflection axis (90, 90a) is arranged such that at least one rope (32, 38) is in contact with the at least one deflection drum (86, 88) and the at least one drive-side drum (20, 22) by a contact circumference (60, 62), or with the at least one deflection drum (86, 88) and the at least one driven-side drum (28, 30).

9. - The drive unit (16, 16a) has a first drive drum (20) and a second drive drum (22) which correspond to at least one of the drive drums (20, 22), - The driven body (24, 24a) has a first driven drum (28) and a second driven drum (30) which correspond to at least one driven drum (28, 30), - The transmission assembly (14, 14a) has a first rope (32) corresponding to the at least one rope (32, 38) and a second rope (38) corresponding to the at least one rope (32, 38), The transmission assembly according to any one of claims 1 to 3, wherein the first rope (32) is operationally connected to the first drums (20, 28, 86) and the second rope (38) is operationally connected to the second drums (22, 30, 88).

10. The transmission assembly according to claim 9, wherein at least one of the second drums (22, 30, 88) is positioned axially offset from the corresponding first drum (20, 28, 86), and / or at least one of the second drums (22, 30, 88) has a different diameter from the corresponding first drum (20, 28, 86).

11. The transmission assembly according to claim 9, wherein the first rope (32) and the second rope (38) are arranged in opposite directions with respect to the drive shafts (18, 18a) in the drive body (16, 16a) and / or are arranged in opposite directions with respect to the drive shafts (26, 26a) in the driven body (24, 24a).

12. The transmission assembly according to claim 9, wherein the drive drums (20, 22) and / or the driven drums (28, 30) are arranged to be rotatable relative to each other.

13. The transmission assembly according to claim 9, wherein the first drive drum (20) and the second drive drum (22) are offset 180° from each other with respect to the driven shafts (26, 26a), and / or the first driven drum (28) and the second driven drum (30) are offset 180° from each other with respect to the drive shafts (18, 18a).

14. The transmission assembly according to claim 9, wherein the drive units (16, 16a) are positioned between the first driven drum (28) and the second driven drum (30) with respect to the drive shafts (18, 18a), and / or the drive units (24, 24a) are positioned between the first drive drum (20) and the second drive drum (22) with respect to the drive shafts (26, 26a).

15. A robot (12) comprising a transmission assembly (14, 14a) according to any one of claims 1 to 3.

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