Planetary transmission assembly

Abstract

Planetary transmission (5) having a sun gear (9), an inner ring gear (6) and a planetary gear carrier (7) having a plurality, preferably three planetary gears (8), characterized in that the axial position of the two transmission parts forming an engagement relative to each other is defined by a magnetic prestressing force.

Description

Technical Field

[0001] The invention relates to a planetary transmission assembly comprising at least two planetary transmission stages, each of which has a sun gear, an internal gear ring and a planetary gear carrier, each of which has a plurality of, preferably three, planetary gears. Background Art

[0002] Such planetary gear transmission assemblies are known and are used, for example, in actuators which are suitable for actuating accessories or valves.

[0003] In order to achieve a desired transmission ratio, planetary transmission assemblies are usually produced in a stacked arrangement with a plurality of transmission stages, wherein each transmission stage is designed as a planetary transmission, wherein such transmission stages are also referred to below as planetary transmission stages.

[0004] Since planetary gears can be used compactly and in a variety of ways, they are usually manufactured in an economical manner, accepting certain manufacturing tolerances.

[0005] In such economically manufactured planetary transmissions, manufacturing tolerances can lead to increased axial play between the individual meshing components, ie the gear wheels.

[0006] If the axial play of the individual movable parts relative to one another becomes too large, undefined operating states may occur, such as only partial overlap of the meshing parts. This causes increased wear in particular and should be avoided. In particular, in the case of multi-stage planetary gear transmission assemblies, the axial play of the individual planetary gear transmissions may increase.

[0007] For this purpose, it is customary to dimension the meshing parts axially sufficiently large so that no partial axial overlap occurs, but rather a complete axial overlap is always maintained. However, this results in large dimensioning and thus in undesirably increased costs. Summary of the invention

[0008] The object of the invention is to minimize the axial play between the gears in a compact planetary transmission while allowing economical production.

[0009] This object is achieved by a planetary gear transmission assembly according to claim 1 .

[0010] The planetary transmission assembly according to the invention, in particular as a planetary transmission, is characterized in particular in that the axial position of the two interlocking transmission components relative to one another is defined by magnetic prestressing and that at least the planetary gear carrier of the first planetary transmission stage and the planetary gear carrier of the second planetary transmission stage are axially tensioned relative to one another by magnetic prestressing. In this way, the relative axial position between the two interlocking components is clearly predefined and defined. Axial partial overlaps and the resulting undefined operating states and increased wear are thus virtually excluded. Thus, even a planetary transmission that can be manufactured at low cost and with tolerances can be designed compactly.

[0011] The magnetic prestressing has the further advantage that a contactless definition of the relative axial position is achieved, thereby generating neither friction nor wear.

[0012] It is unimportant here whether both transmission components, such as gears, which engage with one another are movable or whether one of the transmission components is fixed at least in the axial direction. For example, in a planetary transmission, the ring gear can be fixed. The axial position can now be defined between the ring gear and the planetary gear carrier and / or between the planetary gear carrier and the sun gear.

[0013] The axial position can be defined here directly or indirectly between two gears that are meshed with each other. For example, it is also possible that the axial position is defined between gears that are not meshed with each other, for example between a sun gear and an annulus gear. In this way, the axial position of the meshed gears is indirectly fixed.

[0014] The planetary gear transmission assembly can generally form a planetary gear transmission, for example with or without a housing and / or other functional accessories and / or be designed as a single-stage or multi-stage transmission.

[0015] In one embodiment, the magnetic prestress is defined relative to a transmission component that is connected to the housing and is rotatably mounted, in particular. In this way, a fixed reference point for the axial position is present, whereby component tolerances have less influence on the relative and absolute position of the individual gearwheels.

[0016] In one embodiment, at least the planetary gear carrier of the first planetary gear transmission stage and the planetary gear carrier of the second planetary gear transmission stage are axially tensioned relative to each other by magnetic prestressing. In this way, multiple transmission stages can be axially oriented relative to each other, thereby preventing axial play.

[0017] In one embodiment, the planetary gear transmission has at least two permanent magnets, which are arranged so that the same poles are arranged opposite each other. A force is generated by magnetic repulsion between poles of the same type, which force precisely defines the axial position. Another advantage is that the repulsive force increases significantly as the spacing decreases. Therefore, contact between the two permanent magnets is practically excluded, thereby ensuring reliable maintenance of the position.

[0018] In one embodiment, the first permanent magnet is connected to the planetary gear carrier. In this way, the axial position of the planetary gear carrier and thus of the planetary gears can be defined. However, the first permanent magnet can also be connected to one of the other gears of the planetary gear transmission.

[0019] In one embodiment, the second permanent magnet is arranged on an especially axially fixed transmission component, especially outside the ring gear. In this way, axial positioning of different transmission components relative to one another or between different transmission stages is possible.

[0020] In any case, the first permanent magnet and the second permanent magnet are arranged such that the same magnetic poles face each other and the permanent magnets repel each other.

[0021] Particularly advantageous is a combination in which the first permanent magnet is connected to the planetary gear carrier and the second permanent magnet is connected to a transmission component that is, in particular, axially fixed, wherein the transmission component can also be rotatable relative to the housing. In this way, a defined orientation of the planetary gear carrier relative to the housing is ensured. Since, for example, the ring gear is also fixed to the housing, a defined axial position of the planetary gear carrier, i.e. the planet gears, relative to the ring gear is obtained.

[0022] The permanent magnets can be shaped almost arbitrarily and arranged at suitable locations.

[0023] In an advantageous embodiment, the permanent magnets are designed as ring magnets, which are each arranged coaxially with the sun gear shaft. In this way, a simple arrangement is possible and the repulsive force of the permanent magnets acts in the axial direction relative to the sun gear shaft. As a result, no tilting moments are generated by magnetic forces, which could have a negative effect on the gears.

[0024] In one embodiment, the transmission has a receptacle in which two annular magnets are arranged. The receptacle allows for simple assembly and a defined position of the magnets. Thus, axial positioning of the gearwheels can be achieved.

[0025] In one embodiment, the planetary transmission has at least two transmission stages, each transmission stage being designed as a planetary transmission and the axial position between two transmission stages being defined by magnetic prestressing. Thus, even when a plurality of planetary transmissions are axially joined together, manufacturing tolerances can be compensated and axial play minimized.

[0026] In this way, for example, the axial position of a gearwheel of the first transmission stage relative to a gearwheel of the second transmission stage can also be defined additionally by means of a magnetic prestress.

[0027] The invention also includes a planetary gear transmission assembly having at least two planetary gear transmission stages, wherein each transmission stage is designed as a planetary gear transmission, wherein the ring gears of the two planetary gear transmission stages are axially connected or axially connectable via a locking connection and / or a threaded connection. In this way, a multi-stage planetary gear transmission assembly can be assembled from a plurality of simple planetary gear transmissions, wherein the individual planetary gear transmissions are plugged and / or screwed together in the axial direction. As a result, simple production and simple assembly are possible.

[0028] The individual planetary gears of the transmission stages can preferably be identical, thereby reducing the number of different components or assemblies required. This can result in lower manufacturing costs and simpler assembly.

[0029] In one embodiment, the planetary gear carrier of the first planetary gear stage has at least one locking tongue that can be deflected in the axial direction. A circumferential groove is provided on the sun gear or sun gear shaft of the second planetary gear stage, and the locking tongue engages in the groove when the two planetary gear stages are connected to each other.

[0030] During the connection of two planetary gear transmission stages, the sun gear or sun gear shaft deflects the locking spring in the axial direction by a distance such that the sun gear or sun gear shaft passes through the opening of the locking spring. As soon as the locking spring reaches the groove during further axial introduction, the locking spring locks in the groove and thus establishes the axial connection.

[0031] In one embodiment, a magnetic prestress is formed between the planetary transmission stages as described above. This allows, for example, the axial position of the groove relative to the locking tongue to be defined so that there is no friction or contact during operation.

[0032] Below, the present invention is described in detail with reference to the accompanying drawings according to the embodiments. Here, the embodiments are only used for illustration and are not intended to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings show:

[0034] Figure 1 A cross-sectional view showing an actuator of a multi-stage planetary gear transmission assembly with magnetic axial prestressing;

[0035] Figure 2 Show Figure 1 A cross-sectional view of an actuator with details in the area of ​​the permanent magnets for axial prestressing;

[0036] Figure 3 An oblique view of a section showing a detail of a planetary gear transmission assembly in the region of permanent magnets for axial prestressing;

[0037] Figure 4 A sectional view showing a detail of a planetary gear transmission assembly in the region of permanent magnets for axial prestressing;

[0038] Figure 5 An oblique view showing the locking connection; and

[0039] Figure 6 An oblique view of a section through a planetary gear transmission assembly with a locking connection is shown. DETAILED DESCRIPTION

[0040] Figure 1 The sectional view shows an actuator 1 which has a drive motor 2 , a planetary transmission assembly 3 , control electronics 4 and a housing 10 .

[0041] The drive motor 2 and the associated control electronics 4 are not unimportant to the invention, so these elements are not described in any further detail here. The invention is therefore not restricted in any way to the exemplary embodiments.

[0042] The planetary gear assembly 3 has three planetary gear stages 5, each of which is formed by a planetary gear. Each planetary gear 5 has an internal ring gear 6, a planetary gear carrier 7 with three planetary gears 8, and a sun gear 9. The internal ring gear 6 is respectively connected to the housing 10 in a rotationally fixed manner. The sun gear 9 serves as a drive and the planetary gear carrier 7 serves as an output for each planetary gear 5.

[0043] The individual planetary gear transmissions 5 are arranged one after the other in the axial direction. The sun gear 9 is hollow-bored and is arranged on a feedback shaft 11 .

[0044] The individual planetary gears 5 can be simple and cost-effectively manufactured planetary gears. In order to compensate for any tolerances and axial play, the central planetary gear 5 in the example has a magnetic axial prestressing. It goes without saying that other planetary gears or also multiple planetary gears in a planetary gear can also be magnetically prestressed.

[0045] Figures 2 to 4 The central planetary gear 5 is shown in detail. The first permanent magnet 12 is connected to the planetary gear carrier 7 of the central planetary gear 5. The planetary gear carrier 7 is connected in a rotationally fixed manner to the sun gear 9 of the planetary gear 5 of the adjacent transmission stage.

[0046] In the example, the first permanent magnet 12 is designed as a ring magnet which is arranged coaxially around the sun gear 9 .

[0047] The second permanent magnet 13 is also designed as an annular magnet and is arranged coaxially around the sun gear 9. The second permanent magnet 13 is connected to the transmission component 16 in a rotationally fixed manner. The transmission component 16 is fixed relative to the housing 10 in the axial direction, but is rotatably arranged within the housing 10. The two permanent magnets 12 and 13 are separated by an air gap 14, wherein the magnetic poles of the same pole are opposite each other. The permanent magnets 12, 13 can be magnetized in the axial direction, for example, with one end side being the north pole and the opposite end side being the south pole. In this way, the sun gear 9 can be moved together with the planetary gear carrier 7 in the axial direction within the transmission component 16 by magnetic forces.

[0048] The two permanent magnets 12, 13 extend in a receptacle 15, which is made of plastic, for example. The receptacle 15 surrounds the permanent magnets 12, 13 at the outer circumference and protects them from environmental influences.

[0049] By means of the opposite arrangement of the same magnetic poles, a magnetic repulsive force is generated in the axial direction, which defines the axial relative position of the planetary gear carrier 7 with respect to the transmission component 16. Since the ring gear 6 of the middle planetary gear transmission 5 is also connected to the housing 10 in a rotationally fixed manner, the axial position between the planetary gears 8 of the middle planetary gear transmission 5 and the ring gear 6 is indirectly defined.

[0050] In the example, the components of the individual planetary transmissions 5 are each axially connected to one another via a locking connection 17 . Figure 5 and 6 Such a latching connection is shown in each case.

[0051] In the example, the sun gear 9 is formed integrally with the sun gear shaft 18, wherein the sun gear shaft 18 is extended on one side in the axial direction beyond the sun gear 9. The sun gear shaft 18 has an axial shaft hole 20 for accommodating the feedback shaft 11. Figure 5 In the example shown, the sun gear 9 has a larger diameter than the sun gear shaft 18 .

[0052] As in Figure 6 As can be seen in FIG. 1 , the sun gear 9 can also have the same diameter as the sun gear shaft 18 .

[0053] In the example, the planetary gear carrier 7 is connected to the sun gear shaft 18 in a rotationally fixed manner. The sun gear 9 here belongs to the planetary gear transmission of the subsequent transmission stage. In the example, the planetary gear carrier 7 is designed in the form of a disk. The free end of the sun gear shaft 18, i.e. the axial extension of the sun gear shaft 18, projects beyond the planetary gear carrier 7 in the axial direction.

[0054] In the area of ​​the connection to the sun gear shaft 18, the planetary gear carrier has a pot-shaped drop 19. In the example, the sun gear shaft 18 has a toothing 26, by which a rotationally fixed connection to the planetary gear carrier 7 can be easily achieved. For this purpose, the drop 19 has a corresponding toothing. It is also shown that it is possible to plug the planetary gear carrier 7 onto the sun gear shaft 18 in the axial direction.

[0055] A disk 21 is also provided on the planetary gear carrier 7, which has a coaxial opening 22. The diameter of the opening 22 is in any case larger than the diameter of the sun gear shaft 18. The free end of the sun gear shaft 18 is guided through the opening 22 and extends beyond the disk 21 in the axial direction. At the opening 22, three locking springs 23 are arranged distributed around the circumference at uniform intervals. The locking springs 23 are radially oriented and are configured as spring springs. In the example, the locking springs 23 are extended by gaps 24 in the disk 21. Alternatively, the opening can also have a larger diameter in order to extend the locking springs. In the example, the locking springs 23 are radially oriented with respect to the opening, but other orientations are also possible.

[0056] The sun gear shaft 18 has a circumferential locking groove 25 , into which the locking tongue 23 engages when two such planetary gears are connected to one another.

[0057] When the planetary gear carrier 7 is inserted onto the sun gear shaft 18, the locking tongue 23 is axially deflected by the free end of the sun gear shaft 18 by such a distance that the sun gear shaft 18 can move along the locking tongue 23. Once the locking tongue 23 reaches the locking groove 25, it is locked there.

[0058] Preferably, the free end of the sun gear shaft 18 has a chamfer or a rounded corner, which can facilitate the introduction.

[0059] A plurality of planetary gear transmissions can be easily connected axially to one another via the locking connection 17 in order to obtain a multi-stage planetary gear transmission in this way. In this case, the individual sun gear shafts 18 and the planetary gear carriers 7 of the individual transmission stages are pushed successively onto the feedback shaft 11, wherein the sun gear shafts and the planetary gear carriers are connected to one another in the axial direction via the locking connection 17.

[0060] Although the magnetic prestressing force and the locking connection are shown in combination with each other in the exemplary embodiment, the two designs can also be used and applied separately. Thus, it is easy to use the magnetic prestressing force in a single-stage planetary gear transmission, for example. It is also possible to use the axial locking connection without the magnetic prestressing force.

[0061] Reference numerals list

[0062] 1 Actuator

[0063] 2 Drive motor

[0064] 3 Planetary gear transmission components

[0065] 4 Control electronics

[0066] 5 planetary gear transmission, transmission stage, planetary gear transmission stage

[0067] 6 Internal gear ring

[0068] 7 Planetary gear carrier

[0069] 8 Planetary gears

[0070] 9 Center gear

[0071] 10 Housing

[0072] 11 axis, feedback axis

[0073] 12. First permanent magnet

[0074] 13. Second permanent magnet

[0075] 14 Air Gap

[0076] 15 Accommodation

[0077] 16 Housing parts, transmission parts

[0078] 17 Locking connection

[0079] 18 Central gear shaft

[0080] 19 Descending part

[0081] 20 Shaft hole

[0082] 21 Plates

[0083] 22 Opening

[0084] 23 Locking spring

[0085] 24 Gap

[0086] 25 Locking groove

Claims

1. A planetary gear transmission assembly (3), comprising at least two planetary gear transmission stages (5), each of which has a sun gear (9), an internal gear (6) and a planetary gear carrier (7), wherein the planetary gear carrier has a plurality of, preferably three, planetary gears (8), It is characterized in that The axial position of the two transmission components forming the engagement relative to one another is defined by the magnetic prestressing, and By means of the magnetic prestressing, at least the planetary gear carrier (7) of the first planetary gear stage (5) and the planetary gear carrier (7) of the second planetary gear stage (5) are axially tensioned relative to one another.

2. The planetary gear transmission assembly (3) according to claim 1, It is characterized in that The magnetic prestress is defined relative to a transmission component (16) which is connected to the housing (10) and is particularly rotatably mounted.

3. A planetary gear transmission assembly (3) according to any one of the preceding claims, It is characterized in that The planetary gear transmission (3) has at least two permanent magnets (12, 13) which are arranged such that the same magnetic poles face each other.

4. The planetary gear transmission assembly (3) according to claim 3, It is characterized in that The first permanent magnet (12) is connected to the planetary gear carrier (7), and / or the second permanent magnet (13) is connected to a transmission component (16), in particular to an axially fixed transmission component (16), in particular outside the ring gear (6).

5. A planetary gear transmission assembly (3) according to claim 3 or 4, It is characterized in that The permanent magnets (12, 13) are designed as ring magnets which are each arranged coaxially with respect to a sun gear shaft (18).

6. The planetary gear transmission assembly (3) according to claim 5, It is characterized in that The planetary gear (3) has a receptacle (15) in which two ring magnets (12, 13) are arranged.

7. A planetary gear transmission assembly (3) according to the preamble of claim 1 or any one of the preceding claims, It is characterized in that At least two planetary transmission stages (5) are axially connected or axially connectable via a locking connection (17).

8. The planetary gear transmission assembly (3) according to claim 7, It is characterized in that The planetary gear carrier (7) of the first transmission stage (5) has at least one locking tongue (23) which can be deflected in the axial direction, so that a circumferential locking groove (25) is provided on the sun gear (9) or the sun gear shaft (18) of the second planetary gear transmission stage (5), and when the two planetary gear transmission stages are connected to each other, the locking tongue (23) engages in the locking groove (25).

9. A planetary gear transmission assembly (3) according to claim 7 or 8, It is characterized in that The locking spring (23) is arranged at a coaxial opening (22) through which the sun gear (9) or the sun gear shaft (18) can be passed or is passed.

10. A planetary gear transmission assembly (3) according to any one of claims 7 to 9, It is characterized in that Three locking springs (23) are arranged at the opening (22), in particular, the locking springs (23) are evenly distributed around the circumference of the opening (22).

11. An actuator (1) having a planetary gear transmission assembly (3) according to any one of the preceding claims.

Images