WO2008037563A1 - Multi-stage reduction gear - Google Patents

Abstract

The invention relates to a multi-stage reduction gear, in which a first reduction stage is designed as a planetary transmission (8) with a first sun gear (22) that can be driven, several first planetary gears (20) that are rotatably mounted in a first rotatably mounted planetary carrier (10), said gears simultaneously engaging with the first sun gear (22) and a rotatably mounted first internal gear (16). A second reduction stage comprises at least two pinions (4, 6), both of which engage with a large wheel (2) at different points on the circumference of the latter. The first pinion (4) is rotationally fixed to the first planetary carrier (10) and at least the second pinion (6) has a drive connection to the first internal gear (16) by means of a toothed wheel stage (12, 14) that reverses the direction of rotation. The gear is also equipped with at least one additional similar reduction gear, said two or more reduction gears having a common large wheel (2).

Description

 Multi-stage reduction gearbox

The present invention relates to a multi-stage reduction gear according to the preamble of patent claim 1.

From DE 2420232 A1 a two-stage reduction gear is known, in which a first reduction stage is designed as a planetary gear and in which a second Untersefzungsstufe three pinions, which are at respective different locations on the circumference in Zahπeingriff with a large gear and of which a first pinion rotatably is connected to the planet carrier of the planetary gear and the two other pinions are triebiich connected via a spur gear with the ring gear of the Pianetengetriebes.

In a relatively compact design very high torque can be transmitted in a highly translatable with such a transmission.

The present invention has for its object to further develop such a transmission, so that at approximately the same space requirement higher torques and benefits are transferable.

This object is solved by the features of patent claim 1. Further embodiments and advantages of the invention will become apparent from the dependent claims.

Accordingly, a multi-stage reduction gear is proposed, in which a first reduction stage is designed as Pianetengetriebe, with an apprehensible first sun gear, with a plurality rotatably mounted in a first planet carrier rotatably mounted first Plaπetenrädem in simultaneous meshing with the first sun gear and a likewise rotatably mounted first Ring gear, in which a second reduction gear stage at least two pinion υmfasst, both of which are in different positions on the circumference in meshing engagement with a large gear and of which a first pinion rotatably connected to the first planet carrier and at least a second pinion is connected via a reversing direction gear stage drivingly connected to the first ring gear.

According to the invention, at least one further similar reduction gear is present, wherein the at least two reduction gear have a common large gear. This is possible because the first reduction stages with respect to the central axis of the large gear are arranged radially outwardly offset at a position of the circumference of the large wheel. Depending on the circumferential size of the large wheel, two, three or more first reduction stages can be distributed around the circumference of the large wheel with corresponding torque requirements. Each first reduction stage may be associated with its own electric drive motor, so that overall with the number of first reduction stages and the overall performance of the drive system thus formed increases accordingly.

The entire system can also be described such that a plurality of "drive units" are driven off via at least two pinions on a common large wheel Each of these "drive units" comprises in each case the planetary gear, the pinions and the direction of rotation reversing gear stage,

In many applications, which have a large large wheel, for example, the rotary drive for a turret or the rotary drive of a crane, it is possible to provide the required drive power using several identical and therefore less expensive "drive units" increased operational safety due to redundancy. For Präzistonsanwendungen as a robotic gearbox, where it depends on backlash and flexible lead management, the pinion and the large wheel can be conical, with Einstelimittei for adjusting the axial position of each pinion relative to the large wheel are available. In this case, the large wheel having a central passage, which is usable for the implementation of supply and control lines.

If higher overall ratios are required, the first reduction stage can be preceded by a further reduction stage designed as a pianeta stage, wherein a second planetary carrier is rotatably connected to the first sun gear, second planetary gears are rotatably mounted in the second planet carrier and in constant meshing engagement with a second sun gear rotatably drivable stand a rotatably connected to the first ring gear, second Hohirad.

This Vorschaitstufe is particularly inexpensive to produce when the first and the second ring gear are formed as a single Hohlradbauteii, wherein the first and the second planet gears engage with their teeth on different axial portions of the Hohlradbauteiis or even the Hohlradbauteil has a continuous toothing.

The large gear and the pinions can also be designed as bevel gears with non-parallel axes of rotation in order to take account of particular installation tolerances.

Particularly advantageous conditions arise when both pinions have the same number of teeth and when the direction of rotation reversing gear stage in the ratio (u / (u + 1)) slowed down, where u the ratio of ring gear to sun gear number of teeth in the upstream Planeteπ- gear equivalent. The invention will be explained in more detail below by way of example with reference to the attached figures. Show it;

1 shows a longitudinal section of a transmission.

Fig. 2 is a schematic plan view of a transmission;

Fig. 3 is a schematic 3D view of a transmission and

Fig. 4 is a plan view of a Erftndungsgemäßes transmission.

Figs. 1 to 3 serve to explain the structure of the transmission according to the invention shown in Fig. 4, which as the only all Merkmaie of the present invention has.

Fig. 1 shows a multi-stage reduction gear 1. A first reduction stage is formed of a planetary gear 8, while a second reduction stage comprises two pinions 4, 6, which are engaged with a large gear 2 at different positions on the circumference of the large wheel. In this case, the first pinion 4 is rotatably connected to a planet carrier 10 of the planetary gear 8 and the second pinion is formed by a spur gear 12, 14 spur gear in triebiicher connection with a ring gear 16 of the planetary gear 8. Above and below the center line in Fig. 1st Different cutting planes are shown.

From Fig. 2 and 3, the position of the spur gears 12, 14 is visible to each other, which are engaged with each other. The planetary gear 8 acts aiso as a differential gear, are coupled to the planet carrier 10 and ring gear 16 via the Stirnradstυfe 12, 14, the pinion 4 and the large gear 2 with each other driebfich

In the planet carrier 10 planetary gears 20 are rotatably mounted on Pianetenbolzen 18, which are in simultaneous meshing with the Hohirad 16 and a sun gear 22.

The planetary gear 8 formed from sun gear 22, planet gears 20 and Hohirad 16 is preceded by a further, designed as a planetary stage reduction stage. This includes the mounted on the Pianetenträger 24 planet gears 26, which are in simultaneous meshing with the driven by an electric motor, not shown sun gear 28 and the ring gear 16.

In this case, the ring gears of the two Pianetenstufen are rotatably connected to each other, in the illustrated embodiment, the ring gears are united in a Hohlradbauteil 16, which even has a continuous toothing. The planet gears 20 and 26 are thus at different axial portions of the same Hohirads 16 with this engaged.

The fact that the ring gear is not stationary during operation, thereby has an advantageous effect on the translation of the upstream planetary stage.

Both the pinion 4, 6 and the large gear are conical. Shims 30, which are arranged between the snap ring 32 and the bearing inner ring of the Ritzefagers 34, serve as adjusting means for adjusting the axial position of each pinion relative to the large gear. Thus, the Verzahnungsspie! between pinion and large gear, which has the greatest impact on the overall play of the transmission, can be adjusted or eliminated, so that a precision necessary for a robot gear is achieved. For the crack! 4, 6 is still a second bearing 36 is disposed on the other side of the toothing plane, which is arranged axially between the pinion and the toothing plane of the spur gears 12, 14.

The large wheel has a central passage 40, which can be used in a robotic gearbox to perform control and supply lines.

Between the large gear 2 and the rotatable relative to the large wheel assembly 42, in which the pinions are mounted, two axially salaried bearings 44, 46 in O arrangement available. This type of bearing is precise and allows high axial and lateral forces to support.

Same positions are provided in the other figures with the same reference numerals.

Fig. 4 shows in plan view schematically a transmission according to the invention. In this share two similar reduction gear a common large wheel, so that not only two but four pinions mesh with the Großrad. In this way, a doubling of the transmittable torque and the transmittable power is achieved.

reference numeral

1 reduction gear

2 big wheel

4 pinions

6 pinions

8 planetary gear

10 planet carriers

12 spur gear

14 spur gear

16 ring gear

18 planet bolts

20 planetary gear

22 sun wheel

24 planet carriers

26 PSanet wheel

28 sun wheel

30 adjustment disk

32 snap ring

34 bearings

36 bearings

40 central passage

42 unit

44 bearings

46 bearings

Claims

claims 1. Multi-stage reduction gear in which a first reduction stage is designed as a planetary gear, with a drivable first sun gear (22), with a plurality of rotatably mounted in a first rotatably mounted Pfanetenträger gerotor first planetary gears (10), in simultaneous tooth engagement with the first Sun gear (22) and also rotatably mounted first Hohirad (16) are, in which a second reduction stage comprises at least two pinions (4, 6), both of which are in meshing engagement with a large wheel (2) at different locations on the circumference and of which a first pinion (4) rotatably connected to the first planet carrier (10) and at least one second pinion (6) via a direction of rotation reversing gear stage (12, 14) is triebiich connected to the first Hohirad (16), characterized in that at least one another similar reduction gear is present, wherein the at least two reduction gear is a common Großrad (2). 2. reduction gear according to claim 1, characterized in that the crack! (4, 6) and the large gear (2) are conical and that Einstellelittei (30) for adjusting the axial position of each pinion (4, 6) relative to the large wheel (2) are present, 3. Reduction gear according to one of the preceding claims claim 1, characterized in that the large wheel (2) has a Zentraidurchiass (40). 4. reduction gear according to one of the preceding claims, characterized in that the first Uπtersetzungsstufe is preceded by a further designed as a planetary stage reduction stage, wherein a second planet carrier (24) rotationally fixed to the first sun gear (22) is connected, second planet wheels (26) in the second Pianetenträger (24) are rotatably mounted and in constant mesh with a rotatably driven second sun gear (28) and one with the first ring gear (16) rotatably connected, second Hohirad (16). 5. reduction gear according to one of the preceding claims, characterized in that the first and the second ring gear are formed as a single Hohlradbauteil (16), wherein the first and the second planetary gears engage with their teeth at different axial portions of the Hohlradbauteiis. 6. reduction gear according to claim 6, characterized in that the Hohiradbauteil (16) has a continuous toothing. 7. reduction gear according to one of the preceding claims, characterized in that the large gear (3) and the pinions are formed as bevel gears with non-parallel axes of rotation, 8. Reduction gear according to one of the preceding claims, characterized in that both pinions (4, 6) of the output stage have the same number of teeth and that the reversing Stirnrad- or bevel gear stage (12, 14) in the ratio (u / (u + 1)) is slowed down, where u corresponds to the ratio of the ring gear to Sonnenrad teeth number in the upstream Pfanetensatz