Reducer with at least a first and a second planetary gear stage
By designing a planet carrier and sun gear with pins in a planetary gear reducer, the axial through holes and recesses of the disk are used to form a lubrication channel, which solves the problems of unsustainable lubrication supply and friction in the prior art, and achieves high durability and compact design of reducer.
Patent Information
- Application Number
- CN201980060894.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Priority Date
- 2018-09-18
- Filing Date
- 2019-08-28
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2039-08-28
AI Technical Summary
Existing planetary gear reducers are difficult to achieve high durability in compact structures, and the lubrication supply is not continuous, resulting in friction and contact problems.
Design a planet carrier and sun gear with pins, and the disk is arranged in the middle as a spacer and lubrication channel. The axial through-holes and recesses of the disk form a radial channel to ensure the continuous supply of lubricating oil and prevent the sun gear from contacting. Nitrogen treatment and clamping ring fixation are used to improve structural stability.
It realizes a compact structural design, improves the service life and lubrication effect of the reducer, reduces the friction coefficient and friction heat, and ensures the continuous supply of lubricating oil and the effective lubrication of planetary gears.
Smart Images
Figure CN112703333B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a reduction gear having at least a first planetary gear stage and a second planetary gear stage. Background Art
[0002] As is known, in a planetary gear stage, the planetary gears mesh with a ring gear having an internal toothing and a sun gear having an external toothing.
[0003] As the closest prior art, JP 2016-125 5065 A discloses a planetary gear reducer.
[0004] DE 10 2015 006 023 A1 discloses a reduction gear having an input shaft which is supported in a flange part by means of a bearing.
[0005] A starter disk is known from DE 20 2011 102 802 U1.
[0006] KR 10 2015 0 001 335 A discloses a method for reducing friction between a pinion and a housing. Summary of the invention
[0007] The object of the present invention is therefore to improve a reduction gear in which a high degree of durability can be achieved with a compact design of the reduction gear.
[0008] According to the invention, this object is achieved by a reduction gear according to the features specified in claim 1 .
[0009] In a reduction gear having at least a first planetary gear stage and a second planetary gear stage, an important feature of the invention is that the first planetary gear stage has a first planet carrier with a pin, on which a first planetary gear is rotatably supported, the first planetary gear meshing with the first sun gear,
[0010] The second planetary gear stage has a second planet carrier with a pin, on which second planetary gears are rotatably supported and mesh with the second sun gear.
[0011] The first planet carrier and the second sun gear are connected in a non-rotatable manner.
[0012] In this case, a disk is received centrally in the first planet carrier in a recess, in particular in an axially continuous recess.
[0013] The disk is arranged axially between the first sun gear and the second sun gear.
[0014] The advantage here is that the disk can be used as a spacer so that the two sun gears are kept away from each other, thereby increasing the service life. Thus, only one axially thin disk is arranged in the middle and a compact design is thus achieved. In addition, the disk can be used to improve the lubrication supply, thereby also increasing the service life of the reducer.
[0015] In an advantageous embodiment, the first and / or second sun gear is hollow in design. Advantageously, the lubricating oil passes through the sun gear until it reaches the disk and there through a hole arranged centrally in the disk, so that the radially extending channel can be used as a lubricating channel.
[0016] In an advantageous embodiment, the disk is arranged coaxially with the first and / or second sun gear. This has the advantage that the arrangement is balanced. In addition, the rotation axis passes through the hole arranged centrally in the disk and thus enables a continuous lubricant supply. In contrast, in a non-central arrangement, a continuous lubricant supply cannot be reliably ensured.
[0017] In an advantageous embodiment, the radial distance region covered by the disk includes the radial distance region covered by the first sun gear.
[0018] In particular, the radial distance region covered by the disk includes or overlaps the radial distance region covered by the second sun gear. The advantage here is that it can be ensured that the two sun gears are completely prevented from contacting each other.
[0019] In an advantageous embodiment, the disk is held in the first planet carrier in a force-locking manner, in particular by means of a clamping ring. This has the advantage that a simple and cost-effective fixing method can be used.
[0020] In an advantageous design, the first planet carrier has an axially through stepped hole.
[0021] The disc abuts against the first step of the stepped hole.
[0022] In particular, the bearing of the first planetary gear abuts against the second step of the stepped hole. This has the advantage that the disk can be reliably fixed. In addition, the first sun gear abuts against the disk on the side of the disk facing away from the first step. Therefore, the disk is pressed against the first step and is thus reliably held.
[0023] In an advantageous embodiment, the disk is made of steel and is nitrided / nitrated. This has the advantage that simple production and a low friction coefficient can be achieved.
[0024] In an advantageous embodiment, the disk has a centrally arranged, axially continuous hole. This has the advantage that the lubricating oil passes through the hole, ie, without the action of centrifugal forces. This is because the centrifugal forces are also zero when the radial distance is zero.
[0025] In an advantageous embodiment, one or more recesses are provided on the side of the disk facing the first sun gear, each of which extends from a centrally arranged, axially continuous hole in the disk to the radial outer edge of the disk.
[0026] In particular, channels are formed which are delimited by the disk and the first sun gear, respectively,
[0027] In particular, the depressions and / or channels are regularly / evenly spaced from one another in the circumferential direction. This has the advantage that the lubricating oil passes through the holes and can then be conveyed radially. In this way, the planetary gears arranged at a non-zero radial distance, in particular their needle bearings, can be lubricated in a simple manner; this is because the planetary gears are supported by means of needle bearings which are pushed onto pins of the planet carrier.
[0028] In an advantageous embodiment, the channel cross section first increases and then decreases with increasing radial distance. The advantage here is that, by increasing the channel cross section with increasing radial distance to a maximum value, a buffer volume is provided, which even when filled discontinuously with lubricating oil enables continuous outflow at greater radial distances, since the channel cross section decreases again from the maximum value as the radial distance increases further. The channel then opens to the planetary gear, in particular to its bearing, at this maximum radial distance.
[0029] In an advantageous embodiment, the reduction gear has a third planetary gear stage.
[0030] The third planetary gear stage has a third planet carrier with a third pin, on which a third planetary gear is rotatably supported and meshes with a third sun gear.
[0031] The third planet carrier is connected to the first sun gear (30) in a manner that they cannot rotate relative to each other.
[0032] In this case, a further disk is received centrally in the third planet carrier in a recess, in particular in an axially continuous recess.
[0033] The further disk is arranged axially between the first sun gear and the third sun gear,
[0034] In this case, the third sun gear is designed as a solid component, i.e., not hollow. The advantage here is that a further disk is arranged axially in front of the first sun gear shaft, which is similar in structure to the above-described disk, but abuts against the third sun gear shaft, which is designed as a solid component. As a result, it is not possible to convey lubricating oil in the axial direction through the further disk and the third sun gear shaft, but the lubricating oil must be conveyed radially outwards toward the bearing through the further recess of the further disk. The corresponding further holes of the further disk thus only open into the channel formed by the further recess, and not also into the channel that passes through the third sun gear shaft in the axial direction.
[0035] In particular, the further disk is arranged coaxially with the first and / or third sun gear. In particular, the radial distance area covered by the further disk contains the radial distance area covered by the third sun gear. In particular, the radial distance area covered by the further disk includes or overlaps the radial distance area covered by the third sun gear. In particular, the further disk is retained in the third planet carrier in a force-locking manner, in particular by means of a further clamping ring. In particular, the third planet carrier has a further stepped hole extending axially through,
[0036] wherein the other disk abuts against the first step portion of the other stepped hole,
[0037] In particular, the bearing of the third planetary gear abuts against the second step portion of the other stepped hole.
[0038] In particular, the further disk is made of steel and is nitrided.
[0039] In particular, the further disk has a centrally arranged, axially continuous opening.
[0040] In particular, one or more further recesses are provided on the side of the further disk facing the third sun gear, each of which extends from a centrally arranged, axially continuous further hole of the further disk to the radial outer edge of the further disk.
[0041] In particular, further channels are formed which are delimited by the further disk and the third sun gear, respectively,
[0042] In particular, the further recesses and / or the further channels are / are regularly spaced apart from one another in the circumferential direction.
[0043] In particular, the channel cross section of the further channel initially increases and then decreases with increasing radial distance.
[0044] In particular, the hole of the further disk opens into the further depression and / or the further channel, in particular so that lubricating oil entering through the hole of the further disk is conveyed radially outwards through the further channel and does not pass axially through the third sun gear.
[0045] In an advantageous embodiment, the corresponding planet carrier has a radially inwardly directed depression, in particular a notch, on its radial outer circumference at a circumferential location, in particular in the first circumferential angle region, which is designed to be axially continuous. Thus, rotational speed monitoring can be realized in a simple manner by means of a sensor arranged inside the reducer.
[0046] Further advantages are given by the dependent claims. The invention is not limited to the feature combinations of the claims. For a person skilled in the art, in particular from the objectives proposed and / or by comparison with the prior art, other reasonable combinations of the claims and / or individual claim features and / or description features and / or drawing features are available. BRIEF DESCRIPTION OF THE DRAWINGS
[0047] The present invention will now be described in detail with the aid of a schematic diagram:
[0048] exist Figure 1 1 shows a planet carrier 2 of a reduction gear according to the invention with a disk 3 in a top view.
[0049] exist Figure 2 In FIG. 2 , the disk 3 is shown exploded relative to the planet carrier 2 in an oblique view.
[0050] exist Figure 3 The reducer is shown in a cross-sectional view.
[0051] exist Figure 4 A part of the reducer is shown enlarged in FIG. DETAILED DESCRIPTION
[0052] As shown in the figure, the reduction gear has a plurality of planetary gear stages with a plurality of sun gears, between which a disk 3 is arranged axially in the middle.
[0053] As in Figure 1 and Figure 4 As shown in , the disk 3 has a through hole, particularly a bore hole and a radially extending recess, particularly a groove, arranged centrally therein. Here, the recess extends from the hole to the radial outer edge of the disk 3.
[0054] In this way, lubricating oil can be conveyed radially outwards from the openings during the rotational movement of the disk 3 .
[0055] The disk is made of steel and subsequently undergoes a nitriding treatment, thereby reducing the coefficient of friction of the sun gear (30, 33) with respect to the two contact disks 3. Furthermore, the disk is thereby hardened and less susceptible to deformation.
[0056] The disk is received in a centrally arranged, axially continuous recess in the planet carrier 2 .
[0057] The disk 2 is preferably held in the planet carrier 2 in a non-positively locking manner, in particular by means of a clamping ring.
[0058] As in Figure 3 and Figure 4 As shown in the figure, the first sun gear 30, in particular the first sun gear of the front transmission stage, in particular the planetary gear stage, is driven and meshes with the first planetary gear 31, which is supported on the planetary gear pin 1 and is connected to the planet carrier 2 in a positive locking manner or is formed integrally with the planet carrier.
[0059] The planet carrier 2 drives a second sun gear 33 , to which the planet carrier is at least connected in a rotationally fixed manner or is formed in one piece.
[0060] The second sun gear 33 meshes with second planetary gears 34 , which in turn are mounted on pins which are connected in a form-fitting manner to the second planet carrier 35 or are formed integrally therewith.
[0061] The second planet carrier 35 drives the output shaft 36 of the reducer, but the output shaft can also be designed as an input shaft of the output gear stage.
[0062] The disk 3 is therefore received in the planet carrier 2 and is arranged axially between the first sun gear 30 and the second sun gear 33. This prevents direct contact between the two sun gears (30, 33).
[0063] Since the oil entering through the opening arranged centrally in the disk 3 is also conveyed radially, improved lubrication, in particular of the planetary gears 31 , can be achieved.
[0064] The first planetary gears 31 each mesh with a first ring gear having an internal toothing which also serves as a housing component.
[0065] The second planetary gears 34 each mesh with a second ring gear with internal toothing, which also serves as a further housing component.
[0066] The toothed rings are connected to one another in a sealed manner, ie with a high degree of protection, in particular by screwing.
[0067] Preferably, the centrally arranged, axially continuous recess of the planet carrier 2 is designed as a stepped hole, so that the disk 3 abuts against the step of the stepped hole. Since the first sun gear 30 has steel on the end side, that is, in the area contacting the disk 3, the first sun gear 30 has a low friction coefficient relative to the nitrided disk 3.
[0068] Since the second sun gear 33 comprises steel on the end side, ie in the region of the contact with the disk 3 , the second sun gear 33 has a low coefficient of friction relative to the nitrided disk 3 .
[0069] This prevents the two sun gears (30, 33) from fusing together.
[0070] The two sun gears (30, 33) are designed as hollow parts. Therefore, the two sun gears each have a centrally arranged, axially continuous recess, in particular a hole.
[0071] Since the depression is delimited by the disk 3 and the first sun gear 30 , the channel thus formed leads radially outwards from the cavity of the first sun gear 30 and opens into the radial spacing region covered by the needle bearings of the first planetary gears 31 .
[0072] Here, the needle bearing is inserted on the pin 1, and the planetary gear 31 is inserted on the needle bearing. In addition, the lubricating oil radially conveyed through the channel also flows into the region of the tooth recess of the planetary gear 31.
[0073] As in Figure 1 and Figure 2 As shown in , the channel is continuous on both radial sides, that is, it is continuous from the centrally arranged hole radially outward at a first circumferential position, and is also continuous from the centrally arranged hole radially outward at a position shifted by 180° in the circumferential direction.
[0074] The channel cross section is designed to be independent of the radial distance.
[0075] In other embodiments according to the invention, three or more such channels are provided in the disk 3 extending radially outwards from a centrally arranged hole, in particular wherein the channels are regularly spaced apart from one another in the circumferential direction.
[0076] In other embodiments according to the present invention, the corresponding channel cross section is configured to taper gradually with increasing radial distance, so that the oil flows out more continuously.
[0077] In other embodiments according to the invention, the channel cross section first increases with increasing radial distance and then decreases again. In this way, a high-speed, more continuous oil flow can be ensured, because the increased channel cross section acts as a buffer and is subject to large centrifugal forces due to the greater radial distance. That is, even when the overflow of oil through the hole occurs irregularly, a continuous outflow can be achieved.
[0078] As shown in the figure, the respective sun gear shafts (30, 33) arranged axially before and after the disk 3 are designed to be hollow, i.e. have an axially continuous hole. However, in other embodiments according to the invention, one of the sun gear shafts can be designed as a solid component, i.e. without an axially continuous central recess. In this case, the lubricating oil can no longer flow from the sun gear shaft arranged axially before the disk through the hole of the disk to the sun gear shaft arranged axially after the disk, but must flow radially outwards through the channel formed by the recess so as to be able to lubricate the bearing arranged there.
[0079] At circumferential locations, the respective planet carrier has axially continuous cutouts, i.e. radially directed depressions on its outer circumference. This not only results in better mixing of the lubricating oil and thus improved thermal balance, but also in speed monitoring of the planet carrier via sensors, in particular inductive proximity sensors, arranged in the housing of the reducer.
[0080] List of reference numerals:
[0081] 1 Pin section
[0082] 2 Planet carrier
[0083] 3 plates
[0084] 30 First sun gear
[0085] 31 First planetary gear
[0086] 32 First planet carrier
[0087] 33 Second sun gear
[0088] 34 Second planetary gear
[0089] 35 Second planet carrier
[0090] 36 Output shaft
[0091] Z Local
Claims
1. A speed reducer having at least a first planetary gear transmission stage and a second planetary gear transmission stage, in, The first planetary gear stage comprises a first planet carrier (2) with a pin (1), on which a first planet gear (31) is rotatably supported, the first planet gear meshing with a first sun gear (30), The second planetary gear stage comprises a second planet carrier (35) with a pin, on which a second planet gear (34) is rotatably supported, and the second planet gear meshes with a second sun gear (33). The first planet carrier (2) and the second sun gear (33) are connected in a manner that they cannot rotate relative to each other. It is characterized in that A disk is received centrally in the first planet carrier in an axially continuous recess. The disk is arranged axially between the first sun gear and the second sun gear, and one or more recesses are designed on the side of the disk facing the first sun gear, and the recesses extend from a centrally arranged, axially through hole of the disk to a radial outer edge, so that channels defined by the disk and the first sun gear are formed respectively. The first sun gear is designed to be hollow, and the channels extend radially outward from the cavity of the first sun gear and open into a radial distance area covered by the needle bearings of the first planetary gears. The disk extends radially to a radial distance area covered by the needle bearings of the first planetary gears.
2. The reducer according to claim 1, It is characterized in that The second sun gear is designed to be hollow.
3. The reducer according to claim 1, It is characterized in that The disk is arranged coaxially with the first sun gear and / or the second sun gear.
4. The reducer according to any one of the preceding claims 1 to 3, It is characterized in that The radial distance area covered by the disk includes the radial distance area covered by the first sun gear, The radial distance area covered by the disk includes or overlaps the radial distance area covered by the second sun gear.
5. The reducer according to any one of the preceding claims 1 to 3, It is characterized in that The disk is held in the first planet carrier in a non-positive manner by means of a clamping ring.
6. The reducer according to any one of the preceding claims 1 to 3, It is characterized in that The first planet carrier has an axially penetrating stepped hole. The disc abuts against the first step of the stepped hole. The bearing of the first planetary gear abuts against the second step portion of the stepped hole.
7. The reducer according to any one of the preceding claims 1 to 3, It is characterized in that The disk is made of steel and is nitrided.
8. The reducer according to any one of the preceding claims 1 to 3, It is characterized in that The recesses and / or channels are regularly spaced apart from one another in the circumferential direction.
9. The reducer according to any one of the preceding claims 1 to 3, It is characterized in that With increasing radial distance, the channel cross section first increases and then decreases.
10. The reducer according to any one of the preceding claims 1 to 3, It is characterized in that The holes open into the depressions and / or the channels, so that lubricating oil entering through the holes is conveyed radially outwards through the channels.
11. The reducer according to any one of the preceding claims 1 to 3, It is characterized in that The reducer has a third planetary gear stage. The third planetary gear stage has a third planet carrier with a third pin, on which a third planetary gear is rotatably supported and which meshes with a third sun gear. The third planet carrier is connected to the first sun gear (30) in a manner that they cannot rotate relative to each other. In this case, a further disk is received centrally in the third planet carrier in an axially continuous recess. The further disk is arranged axially between the first sun gear (30) and the third sun gear, In this case, the third sun gear is designed as a solid component, ie, not hollow.
12. Reducer according to claim 11, It is characterized in that The further disk is arranged coaxially with the first sun gear and / or the third sun gear, and / or the radial distance region covered by the further disk includes the radial distance region covered by the third sun gear, the radial distance region covered by the further disk includes or overlaps the radial distance region covered by the third sun gear, and / or The further disk is held in the third planet carrier in a non-positive manner by means of a further retaining ring, and / or The third planet carrier has another stepped hole which is axially continuous. wherein the other disk abuts against the first step portion of the other stepped hole, The bearing of the third planetary gear abuts against the second step portion of the other stepped hole, and / or The further disk is made of steel and is nitrided, and / or The further disk has a centrally arranged, axially continuous opening.
13. The reducer according to claim 12, It is characterized in that One or more further recesses are provided on the side of the further disk facing the third sun gear, each extending from a centrally arranged, axially continuous further hole of the further disk to a radial outer edge. so that further channels are formed which are delimited by the further disc and the third sun gear, respectively, The further recesses and / or further channels are regularly spaced apart from one another in the circumferential direction, and / or The channel cross section of the further channel increases first and then decreases with increasing radial distance, and / or The holes of the further disk open into the further depression and / or the further channel, so that lubricating oil entering through the holes of the further disk is conveyed radially outwards through the further channel and does not pass axially through the third sun gear.
14. The reducer according to any one of the preceding claims 1 to 3, It is characterized in that The first planet carrier has a radially inwardly directed depression on its radial outer circumference in a first circumferential angle region, the depression being designed to be axially continuous, and / or The second planet carrier has, on its radial outer circumference at a circumferential location, a radially inwardly directed recess which is designed to be axially continuous.