DE10003350A1 - Adjustment mechanism to set one component against another has two toothed cogwheels and an input shaft with toothed splines and splined planet wheels for a simple adjustment action with precise positioning - Google Patents

Abstract

The mechanism for an adjustment setting between two components has at least one adjustment cogwheel (1) with a toothed zone (5) and a further cogwheel (2) with a toothed area (6). An input shaft (3) is toothed with splines (14), and at least two planetary cogwheels (10a-10d) have toothed splines (15,16). The teeth (1) of the first cogwheel (1) mesh with one set of planetary splines (15) and the other cogwheel teeth (6) mesh with the other set of planetary splines (16). The splines (14) of the input shaft (3) mesh either with the planetary splines (16) of each planet wheel (10a-1d) or the teeth of the first and second cogwheels. The tooth count at the teeth (5,6) of the two cogwheels (1,2) differ from each other and/or the planetary tooth splines (15,16) have different tooth counts.

Description

The invention relates to an adjusting device for adjusting a second part compared to a first part, especially for adjusting articulated parts such. B. Ro bot joint parts.

When adjusting one joint part compared to another joint part, in particular right of joint parts on a robot arm, is particularly good positionability and torque-resistant movement of the joint parts to each other is required. You can do this u. a. Stepper motors are used, which allow an exact adjustability of the joint parts ensure each other, or z. B. Electric motors with a high gear reduction.

When using motors such. B. electric motors with higher speeds can Required high reduction, for example through gear with an elastic ring gear (Harmonic drive gear) can be realized. With these adjustments or gears are two internally toothed gears with different numbers of teeth and one in the externally toothed, elastic gearwheel provided with toothed gears see that has an elliptical shape and is deformed when turning that his  External teeth pressed into the tooth gaps of the internally toothed gears one after the other be, whereby a relative angle adjustment is achieved, in which the teeth of the au External toothed elastic gear constantly engaged with the internal toothing are. The difference in the number of teeth of the internally toothed gears is greater / = 2.

To achieve large reductions, large numbers of teeth are necessary, for what highly elastic, expensive and friction materials are needed.

The invention is based on the object of improvements over the prior art tion and in particular with an adjustment device and a robot joint to create one or more such adjustment devices that are relatively small Effort, preferably small dimensions and small mass, an accurate and Ensure permanent positionability. A fixed clamp should preferably be used here Mung or self-blocking of the parts or robot joint parts with a high subset tion and as little friction as possible. The adjustment according to the invention device and the robot joint according to the invention should preferably be simple Materials and can be realized with a simple and inexpensive manufacture can.

This object is achieved by an adjusting device for adjusting a first part solved compared to a second part, with two adjusting gears, each on one part or joint part can be fastened and each have an internal toothing, an drive shaft, which is arranged concentrically to the adjusting gears and a Has shaft teeth, and at least two, preferably four and more um running gears, each with a first external toothing and one in the axial direction have the second outer toothing offset from the first outer toothing. Here are the first external toothing engages the first internal toothing of the first ver setting gear and the second external teeth in engagement with the second internal ver toothing of the second adjusting gear, and the outer shaft toothing of the drive shaft is in engagement with one of the two external teeth, d. H. the first or the second External gears. A relative adjustment of the adjustment gears to one another guaranteed by the first internal toothing and the second internal toothing have different numbers of teeth and / or the first external teeth of the  Orbital gears and the second external gears of the orbital gears differ Liche number of teeth.

According to the invention, a relative adjustment of the adjusting gears with internal teeth Achievements achieved by these are connected via common planetary gears by be driven by a drive shaft. The planet gears point axially from mutually separate areas, each with one of the two adjusting gears Internal teeth are engaged. By now the number of teeth of the internal toothing and / or the number of teeth of the axially separated external teeth each Orbital wheel are different from each other, have the first internal toothing and the first external toothing formed first gear system and that of the second Internal toothing and the second external toothing formed second gear system different translations. Since a first external ver toothing and second external toothing are rigidly coupled, the Ver adjusting gears with internal toothing forced to rotate relative.

By the difference in the number of teeth of the internal gear or the external gear is relatively small in relation to the number of teeth ower rotation of the shaft due to the relatively small difference in the number of teeth a very small twist of the internal gears can be achieved, which leads to leads to a high reduction. Thus, high-speed engines with low Torque are used, due to the high reduction a small, ge precisely positionable rotation with relatively high torque can be achieved.

Thus, with few, inexpensive parts that can be manufactured (essentially toothed wheels with internal teeth or external teeth) a smooth, small adjustment device can be realized with low mass, which is nevertheless robust, high torques can transmit and ensures precise position adjustment, fixed in any position jams and has low friction. The adjustment device is easy to do assemble and easy to use.

Since according to the invention motors, in particular electric motors, ver at high speeds can be used, a cost-effective robot joint can also be realized the, in which advantageously the motors and / or adjusting devices in the joint parts  or robot arm parts can be accommodated. Because of the low Mass of the adjustment device according to the invention and the low mass of the used Robust, high-speed motors can produce robot joints with low mass that can move larger loads with smaller robots.

In which the first and second external teeth can have the same number of teeth a high reduction due to a difference in the number of teeth of the internal gears of the adjustment torque can be reached. So that the first and second external teeth of the planet gears respectively in engagement in the first or second internal toothing are, at least in one of the planet gears an angular offset between the at the external gears advantageous. To further increase the position accuracy, it is advantageous to use an oblique or somewhat tapered toothing.

The planet gears can be made from two axially connected individual wheels be put. The individual wheels can be wedged, welded or by means of Screws are connected. The adjusting gears can also be used as sheet metal stampings or pressed sheet metal parts.

By one of the internal gears fixed to the housing and the other internal tooth wheel is connected to an output shaft, a gearbox with high reduction can be used become real. When using planetary gears with the same number of teeth and inside Gear units with different numbers of teeth can be used in a gear unit without rotation reversal can be realized by the adjusting gear with the internal toothing with ge ringerer number of teeth is fixed to the housing, so that by the relative rotation of the Drive shaft to the housing against rotation of the second adjusting gear is effected over the housing with the same direction of rotation.

The invention is in the following with reference to the accompanying drawings tion forms explained in more detail. Show it:

Figure 1a is an adjusting device according to the invention according to a first form from guide in axial section.

. Fig. 1b and 1c are radial sections of the adjustment device of Figure 1a along the lines Section A or B;

Fig. 2 enlargements of detail from Fig. 1b;

FIG. 3a shows an adjustment device according to a second embodiment of the invention in axial section;

. Fig. 3b and 3c radial sections of the adjustment device of Figure 3a lines along the section C and D, respectively;

Fig. 4 is an adjustment device according to a third embodiment of the invention in axial section;

Fig. 5 is an adjusting device according to a fourth embodiment of the invention in axial section;

Fig. 6 shows an inventive robot joint with a plurality of adjustment devices according to the invention in axial section.

According to FIGS. 1a-c, an adjustment device has two adjustment gears 1 , 2 , which abut one another in the axial direction. According to Fig. 1a, a bearing 9 can be provided to support these adjusting gears against each other. The adjusting gears 1 , 2 can also be axially spaced apart from one another as shown in Fig. 1a, so that they are not supported against each other in ra dialer direction.

A drive shaft 3 is a shaft outer teeth 14 in engagement with orbital gears 10 a, 10 b, 10 c, 10 d with first external teeth 15 a, 15 b, 15 c, 15 d. At the drive shaft 3 can, for. B. by a rod-shaped shaft with an attached external gear, or as shown in Fig. 1 directly by a driven hollow shaft with external teeth 14 . The planet gears each have two individual gears 17 , 18 which are axially adjacent to one another or axially spaced apart. The first external toothing is attached to the first single gear 17 , and on the second single gear 18 , a second external toothing 16 a, 16 b, 16 c, 16 d is provided, which is shown in FIG. 1 c. The external teeth 15 a-d and 16 a-d each have the same number of teeth m, z. B. m = 14. As shown in Fig. 1b or the enlargement of Fig. 2, the teeth of the external gears are congruent to each other only on the planet gear 10 a, while in the other planet gears 10 b, 10 c, 10 d, the respective external gears are offset from one another are. In the orbital gear 10 c, which lies opposite the orbital gear 10 a, the teeth of the second external toothing 16 c lie opposite the teeth of the first external toothing 15 c exactly offset by half a tooth. In the other planetary gears 10 b and 10 d, the angular offset is half the angular distance between two teeth.

The first internal toothing 5 of the first adjusting gear 1 has a larger number of teeth n, z. B. n = 92 as shown in FIG. 1, as the second internal toothing 6 of the second adjusting gear 2 . Referring to FIG. 1, this has a number of teeth n - 1, here n = 91 on. The angular offset between the internal gears 5 , 6 is compensated in the epicyclic gear shown by the above-described angular offset of the individual gears 17 , 18 or the first internal gears 15 a-d and the second external gears 16 a-d, so that, according to FIG. 1, the external shaft gearing 14 , the first Außenver serrations 10 a- 10 d, and the first internal teeth 5 form a first pair of gears and the second external gears 16 a- 16 d, and the second internal teeth 6, a second gear pair.

Referring to FIG. 1a, the individual gears 17, 18 connected together by a screw connection 19 may be; a connection by means of gluing or welding is also possible. Here, the individual gears 17 , 18 are rotatably connected to each other, so that no relative rotation of these individual gears zueinan is possible. In addition to the design shown in FIG. 1 with four planetary gears, it is fundamentally also possible to design with two, three or more than four planetary gears, which are each distributed symmetrically around the drive shaft 3 .

When the shaft 3 is actuated, the planetary gears 10 thus perform a circular movement in both adjusting gears, as a result of which the adjusting gears are forced to rotate relative to one another due to the different number of teeth of the internal gears 5 , 6 . Here, the planet gears rotate around adjusting gears with internal gears with different ratios. At z. B. an internal toothing of 92 or 91 teeth and an external toothing of the drive wheel of 64 teeth, a reduction of about 222 is achieved. The reduction can be determined by the number of teeth in the internal gears and the external gears. Different numbers of teeth of the external gears can also be set here, where the number of teeth of the internal gears can be the same or also different.

In Fig. 1 and 3 holes 7 , 8 are used to attach the adjusting gears to the Ge steering parts.

By the number of teeth of the second internal toothing 6 greater than the corresponding number of teeth of the first internal toothing 5 is determined, in contrast to the embodiment shown in FIG. 1, a reversal of the direction of rotation relative to the drive shaft 3 can be fixed.

The Umlaufverstellvorrichtung shown or the epicyclic gearing according to FIG. 1 can be used in particular in such a way that the first adjustment gear wheel 1 is fastened on the housing side, for example. B. with a housing of a motor that drives the drive shaft 3 . In this case, an output is achieved via the second adjusting gear 2 . Alternatively, the second adjusting gear 2 can also be attached to a housing, so that the first adjusting gear 1 can be used as an output.

In the second embodiment shown in Fig. 3a-c, a drive gear 4 is centrally on a drive shaft 13 , z. B. attached by means of the screws or bolts shown. This drive gear 4 with its outer shaft teeth 14 is in engagement with the second outer teeth 16 a-d of the planetary gears 10 a- 10 d, so that an outer wheel pair system is formed. The second external gears 16 a- 16 d are also in engagement with the second internal gearing 6 of the second adjusting gear 2 , whereby an internal gear pair system is formed. The orbital gears 10 a - 10 d formed by two individual gears 17 , 18 have axially offset first external gears 15 a - 15 d which, as in the first embodiment, are offset to the second external gears in the case of three orbital gears. The first external gears 15 a - 15 d are in engagement with the first internal teeth 5 of the first adjusting gear 1 and bil an internal gear pair system; in this embodiment, however, they are not in engagement with the external shaft toothing 14 . By the first adjusting gear 1 is fixed in holes 7 provided in connection bolts 47 with a cover 23 to a housing not shown, the second adjusting gear or an axial cover plate 28 can be taken as an output. By the second internal toothing 6 a number of teeth of n, z. B. n = 92, and the first internal toothing 5 a number of teeth n - 1, z. B. n - 1 = 91, has the same direction of rotation of the second adjusting gear 2 as the drive shaft 13 is achieved.

In Fig. 3, the drive shaft 13 can be mounted via bearings 22 on the first adjusting toothed wheel 1 or the plate 23 and via further bearings on the cover plate 28 .

The further shown embodiments of FIGS. 4 and 5 show hollow shafts 43 , 53 , the other components corresponding to those of FIG. 3.

Fig. 6 shows a robot joint, in which a first joint part 33 , for. B. a robot arm, with a second joint part 34 , and a third joint part 35 , z. B. another Ro boterarmteil connected via adjustment devices according to the invention. The robot arm 33 has a housing 25 in which a motor 24 is arranged. This motor can be an electric motor, for. B. a common high-speed electric motor small size with low torque. The electric motor is connected via a connecting plate 26 and a bolt connection 27 to a first adjusting gear 1 of a first adjusting device 36 according to the invention. This adjustment device 36 may correspond to that of FIG. 3, for example, so that the other components are not discussed here. The shaft 13 of the first motor 24 is connected as in the embodiment of FIG. 3 via planet gears with a second adjusting gear 2 , which is connected via a cover plate 28 and a bolt connection 48 to a housing 30 of the second joint part 34 . When the high-speed electric motor 24 is in operation, its housing 26 is rigidly connected to the housing 25 and the first adjusting gear 1 via the bolt connection 27 , so that, according to the explanations relating to FIG. 3, the second adjusting gear 2 as an output with a high reduction ratio to the drive shaft 13 serves. Here, a high reduction can be achieved in particular with a slight difference in the number of teeth of the first internal toothing and the second internal toothing. The direction of rotation of the second adjusting gear 2 can be set in the desired manner in that the number of teeth of the second internal toothing is larger or smaller than that of the first internal toothing.

Since a high reduction can be ensured according to the invention, inexpensive and fast-running, small-sized electric motor of small size with high speeds and small torque can be used, so that an accurate adjustment and good positionability of the second adjusting gear 2 or the housing seteiles 30 is guaranteed. Here, the adjustment device according to the invention is self-locking, so that a rigid positioning of the housing part 30 can be ensured. In the second joint part 34 , a second motor 29 is provided with a drive shaft 113 , the axis A2 of which is perpendicular to the axis A1 of the first motor 24 or is at least inclined. Referring to FIG. 6, two adjusting devices 31, 32 provided at both ends of the motor 29; training with only one adjustment device is also possible.

The second adjustment device 31 and the second adjustment device 32 are in turn as for. B. those of FIG. 3 constructed. Referring to FIG. 6, a second shift gear 10 is in this case rigidly connected to the housing part 30 via a bolt connection, so that when the loading of the shaft 113 driven by the electric motor 29, an adjustment of this motor 29 or its housing part 126 with a corresponding reduction relative to the shaft 113 via the planetary gears and the first variable gear 101 , which is rigidly connected to the motor housing 126 , is ensured. With the housing 126 of the motor 29 , a flange or a plate 127 can be connected to a third joint part 35 . When the motor 29 is operating, the third joint part 35 is thus rotated about the axis A2 with a corresponding reduction with respect to the shaft 113 .

Thus, a twist with high reduction can be done around axis A1 as well can be guaranteed about the axis A2, with all components, i. H. Engines and Adjustment devices within the joint parts, e.g. B. robotic arms can be accommodated can.

The adjustment device according to the invention can - in addition to the use shown for robot arms - z. B. can be used to adjust various turbine parts. So the output turbine or the output wheel of a turbine, for. B. an aircraft turbine, can be connected via an adjusting device according to the invention with a high reduction ratio to an input fan of the turbine, so that the input fan supplies air to the rear turbine at a relatively low speed at high speed. For egg ne turbine z. B. the embodiments of Fig. 1, 3 or 4, 5 can be used, the adjusting gears can be accommodated in a turbine housing without any problems. In order to ensure a suitable reduction, internal gears with a higher number of teeth than in FIGS . 1 and 3 can also be used; In particular in the case of large aircraft turbines, this number of teeth can be increased significantly in order to achieve the desired reduction on the input fan.

Claims (16)

1. Adjustment device for adjusting a second part with respect to a first part, in particular a second joint part ( 34 ) with respect to a first Ge joint part ( 33 )
a z. B. on the first part attachable first adjusting gear ( 1 ) with a first internal toothing ( 5 ),
a z. B. attachable to the second part second adjusting gear ( 2 ) with a second internal toothing ( 6 ),
a drive shaft ( 3 , 13 , 34 , 35 ) which is arranged concentrically with the first adjusting gear and the second adjusting gear and has external shaft teeth ( 14 ), and
at least two planetary gears ( 10 a-d), each having a first external toothing ( 15 a-d) and a second external toothing ( 16 ad) offset axially to the first external toothing, the first external toothing (15a-d) being in engagement with the first internal toothing ( 5 ) and the second external teeth ( 16 a-d) are in engagement with the second internal teeth ( 6 ), and the external shaft teeth ( 14 ) are in engagement with either the first external teeth ( 15 a-d) or the second external teeth ( 16 ad) is
wherein the first internal teeth ( 5 ) and the second internal teeth ( 6 ) have different numbers of teeth (n, n - x) and / or the first external teeth ( 15 a-d) and the second external teeth ( 16 a-d) have different numbers of teeth (m). 2. Adjusting device according to claim 1, characterized in that the first internal teeth ( 5 ) and the second internal teeth ( 6 ) have different teeth (n, n - x) and the first external teeth ( 15 a-d) and the second external teeth ( 16 ad) have the same number of teeth (m), the first external toothing ( 15 b, c, d) and the second external toothing ( 16 b, c, d) having an angular offset to one another at least in the case of a planetary gear ( 10 b, c, d). 3. Adjusting device according to claim 1 or 2, characterized in that one of the internal gears ( 1 , 2 ) is fixed to the housing and the other internal gear wheel is connected to an output shaft. 4. Adjusting device according to claim 2 and 3, characterized in that the Internal gear with the lower number of teeth fixed to the housing and the In gear with the larger number of teeth is attached to the output shaft. 5. Adjusting device according to one of claims 1 to 4, characterized in that the planet gears ( 10 a-d) each consist of two axially connected NEN, preferably keyed, welded or screwed, individual gears ( 17 , 18 ). 6. Adjusting device according to one of claims 1 to 5, characterized in that concentrically on the drive shaft ( 13 ), a drive gear ( 4 ) with the Wel lenaußen toothing ( 14 ) is attached. 7. Adjusting device according to one of claims 1 to 6, characterized in that the number of teeth (n, n - 1) of the internal gears ( 5 , 6 ) and the number of teeth (m) of the external gears ( 15 a-d, 16 ad) in a ratio of 3: 1 to 12: 1, preferably 5: 1 to 8: 1. 8. Adjusting device according to one of claims 1 to 7, characterized in that the first internal toothing ( 5 ) and the second internal toothing ( 6 ) have the same working diameter and the first external toothing ( 15 a-d) and the second external toothing ( 16 ad) have the same working division diameter exhibit. 9. joint, in particular robot joint, with at least three joint parts ( 33 , 34 , 35 ), a second joint part ( 34 ) via a first adjusting device according to one of claims 1 to 8 compared to a first joint part ( 33 ) about a first axis ( A1) is rotatable and a third joint part ( 35 ) is rotatable relative to the second joint part ( 34 ) via a second adjusting device ( 31 ) according to one of claims 1 to 8 about a second axis (A2) different from the first axis (A1) . 10. Joint according to claim 9, characterized in that the second axis (A2) is rotated with respect to the first axis (A1), preferably perpendicular to this runs. 11. Joint according to claim 9 or 10, characterized in that the first Ge steering part ( 33 ) and the second joint part ( 34 ) are each connected to an adjusting gear ( 1 , 2 ) of the first adjusting device ( 36 ) and / or the second joint part ( 34 ) and the third joint part ( 35 ) are each connected to an adjusting gear ( 101 , 102 ) of the second adjusting device ( 31 ). 12. Joint according to one of claims 9 to 11, characterized in that in the first joint ( 33 ) a first drive motor ( 24 ) for rotating the second Ge joint part ( 34 ) is arranged relative to the first joint part ( 33 ). 13. Joint according to any one of claims 9 to 12, characterized in that a second drive motor (29) is arranged for rotating the third articulated part (35) opposite the second hinge part (34) in the second joint part (34). 14. Joint according to one of claims 9 to 13, characterized in that the second joint part ( 34 ) and the third joint part ( 35 ) via the second adjusting device ( 31 ) and a third adjusting device ( 32 ) according to one of claims 1 to 7 are rotatably connected. 15. Joint according to one of claims 9 to 14, characterized in that the first adjusting device ( 36 ) in the first joint part ( 33 ) and / or the second adjusting device ( 31 ) and optionally the third adjusting device ( 32 ) in the second joint part ( 34 ) are arranged. 16. Joint according to one of claims 9 to 15, characterized in that the adjusting gears ( 1 , 2 ) are connected via a four-point bearing ( 9 ).