CN208252678U - Internal tooth flexbile gear speed reducer - Google Patents
Internal tooth flexbile gear speed reducer Download PDFInfo
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- CN208252678U CN208252678U CN201820854061.8U CN201820854061U CN208252678U CN 208252678 U CN208252678 U CN 208252678U CN 201820854061 U CN201820854061 U CN 201820854061U CN 208252678 U CN208252678 U CN 208252678U
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Abstract
The utility model discloses a kind of internal tooth flexbile gear speed reducers comprising: planetary gear set is provided with the first engaging section and the second engaging section in the planetary gear set;First engaging section of ring gear, the ring gear and planetary gear set connects;Flexbile gear, is provided with interior teeth portion on the flexbile gear inner wall, and the second engaging section of the interior teeth portion and planetary gear set connects;And shell, cavity is provided in the shell, the planetary gear set, ring gear and flexbile gear are arranged in cavity.The utility model joggled strength with higher can reduce part processing precision requirement while reach high-precision exporting, and preparation cost is low, and gear wear is smaller, and invertibity is preferable.
Description
Technical field
The utility model relates to speed reducer fields, and in particular to a kind of internal tooth flexbile gear speed reducer.
Background technique
Speed reducer plays a part of to match revolving speed between prime mover and working machine or executing agency and transmits torque, is a kind of
Accurate machinery relatively.Purpose using it is to reduce revolving speed, increases torque.It many kinds of, model is different, variety classes
There is different purposes, wherein planetary reducer and harmonic wave speed reducing machine are common type.
Planetary reducer is combined closely by an internal gear on tooth case shell, ring tooth center have one from external impetus institute
The sun gear of driving, fall between have one group by more gear combinations in the planetary gear set on planet carrier, planet carrier
On be provided with output shaft, when power drive sun tooth, planetary gear rotation can be driven, and follow the track of internal gear along center
Revolution, planetary gear rotation drive output shaft output power;Especially a kind of differential teeth planetary decelerator, can cross and accomplish than common
The bigger reduction ratio of planetary reducer has two layers of ring gear, and planetary gear quantity is A, and A is >=2 arbitrary integer at this time,
Planetary gear is engaged this two layers of internal tooth simultaneously, and one of ring gear is standard tooth form, and the number of teeth is assumed to be N, another ring gear
It is then variation flute profile, the number of teeth is N+A or N-A, and two ring gears are because of difference with teeth, to form output;
But it exists with inevitable defect:
1. joggled strength is weaker: the ring gear for the flute profile that wherein makes a variation, when engaging with planetary gear, flute profile can not be engaged completely,
For localized contact, and the number of teeth engaged is less, therefore causes joggled strength insufficient, carrying torsion decline;
2. back clearance is larger: since the ring gear of variation flute profile can not completely be engaged with planetary gear, being also easy to produce biggish
Gear back gaps then need higher machining accuracy to improve back clearance;
3. gear wear is larger: when ring gear and the planetary gear engaged transmission for the flute profile that makes a variation, while having rolling friction and cunning
Dynamic friction causes gear to be prone to wear.
Harmonic wave speed reducing machine have one layer of ring gear, number of teeth N, a wave producer, wave number A, and A be >=2 appoint
It anticipates integer, an external tooth flexbile gear, number of teeth N-A, wave producer ejects external tooth flexbile gear when use, makes flexbile gear position of cusp
External tooth is engaged with ring gear, and because of difference with teeth between the two, to form output, harmonic gear reducer has high-precision, Gao Cheng
The advantages that carrying power is compared with common retarder, and since the material used will lack 50%, volume and weight at least reduce 1/3;
But it exists with inevitable defect:
1. requirement on machining accuracy is high, allow part tolerance small: its back clearance is close by ring gear and engaging for flexbile gear external tooth
Degree determines, therefore for ring gear, the size requirement of wave producer, flexbile gear external tooth is high, makes up to the effect tightly engaged;
2. detent torque is larger, the cost of deformation bearing must be increased: between wave producer and flexbile gear inner wall, needing to install additional
One can deformation bearing reduce the friction of wave producer Yu flexbile gear inner wall, therefore in starting moment, need to make deformation axis simultaneously
It holds and flexbile gear generation type becomes, cause detent torque bigger than normal, and the presence of deformation bearing also increases cost;
3. invertibity is poor: it is certain need output end inversely to input when, due to higher detent torque become it is higher
Grip force, it is therefore desirable to which higher reverse input torsion could operate, and be easy injury gear, cause use condition limited.
Summary of the invention
The technical problem to be solved by the present invention is to provide a kind of internal tooth flexbile gear speed reducer, engagement with higher is strong
Degree can reduce part processing precision requirement while reach high-precision exporting, and preparation cost is low, and gear wear is smaller, can
Inverse property is preferable.
In order to solve the above-mentioned technical problem, the utility model provides a kind of internal tooth flexbile gear speed reducer comprising:
Planetary gear set is provided with the first engaging section and the second engaging section in the planetary gear set;
First engaging section of ring gear, the ring gear and planetary gear set connects;
Flexbile gear, is provided with interior teeth portion on the flexbile gear inner wall, and the second engaging section of the interior teeth portion and planetary gear set connects;
And shell, cavity is provided in the shell, the planetary gear set and flexbile gear are arranged in cavity.
Further, the planetary gear set includes at least two planetary power wheels, the planetary power wheel and flexbile gear it is interior
Teeth portion engagement connection, deformation occurs under the elongate support of planet power wheel for the flexbile gear.
Further, the planetary gear set further includes support wheel, the quantity of the support wheel and the quantity of planetary power wheel
Unanimously, the support wheel is arranged between two adjacent planetary power wheels, and the support wheel abuts the internal tooth that flexbile gear is arranged in
In portion.
Further, the planetary power wheel surface is provided with the first teeth portion and the second teeth portion, multiple planets
First teeth portion of power wheel cooperatively forms the first engaging section, and the second teeth portion of multiple planetary power wheels cooperatively forms
Two engaging sections, the teeth quantity in first teeth portion is consistent with the teeth quantity in the second teeth portion or the tooth in the first teeth portion
Tooth quantity be greater than the second teeth portion teeth quantity or the first teeth portion teeth quantity less than the second teeth portion teeth number
Amount.
Further, the support wheel surface is provided with third teeth portion, the interior teeth portion in third teeth portion and flexbile gear
Engagement connection.
Further, the support wheel surface is additionally provided with the 4th teeth portion, and the 4th teeth portion is engaged with ring gear
Connection.
Further, positive wheel is provided among the planetary gear set, the sun wheel is connect with the first power end, the flexbile gear
On be provided with the second power end, first power end and the second power end are respectively set to power input module and power output
Component.
Further, the planet carrier of the planetary gear set is connect with the first power end, and it is dynamic that second is provided on the flexbile gear
Power end, first power end and the second power end are respectively set to power input module and power output component.
The utility model has the beneficial effects that
1. improving joggled strength, the interior teeth portion flute profile of deformable flexbile gear can keep standard tooth form, nibble with planetary gear set
It when conjunction, can completely engage, improve joggled strength, increase carrying torsion;
2. back clearance is smaller, allow lower machining accuracy, due to flexbile gear can deformation, material elastic stress act on
Under, can nature inwardly collect engagement, therefore planetary gear set dimensional tolerance can be absorbed, and because flexbile gear only with inside is set
Planetary gear set engagement, therefore there is no the position precision problems that flexbile gear external tooth is engaged with ring gear, can reduce part processing essence
Degree requires, while guaranteeing good output accuracy;
3. gear wear is smaller, when deformable flexbile gear and planetary gear set engaged transmission, can be considered normal ring gear with
External gear engagement, maintains rolling friction state, reduces gear wear;
4. detent torque is smaller, and the cost of deformation bearing is reduced, eject internal tooth flexbile gear by planetary power wheel, when starting
It does not need to make bearing deformation, therefore detent torque is smaller, while not needing deformation bearing to reduce friction, therefore can reduce into
This;
5. invertibity is preferable, since detent torque is smaller, that is, grip force is smaller, therefore does not need too high reverse defeated
Entering torsion can operate, and invertibity improves.
Detailed description of the invention
Fig. 1 is that the planetary gear of the utility model and flexbile gear cooperate schematic diagram;
Fig. 2 is the cross section structure schematic diagram of the planet carrier driving of the utility model;
Fig. 3 is the cross section structure schematic diagram of the utility model sun wheel drive;
Fig. 4 is the configuration schematic diagram of the utility model Fig. 3;
Fig. 5 is the transmission schematic diagram that the utility model has support wheel;
Fig. 6 is the transmission schematic diagram for the support wheel that the utility model has single layer teeth;
Fig. 7 is the transmission schematic diagram for the support wheel that the utility model has the double-deck teeth;
Fig. 8 is the utility model with number of teeth planetary power wheel schematic diagram;
Fig. 9 is the first different number of teeth planetary power wheel schematic diagram of the utility model;
Figure 10 is second of the utility model different number of teeth planetary power wheel schematic diagram.
Figure label explanation: 1, planetary gear set, the 11, first engaging section, the 12, second engaging section, 13, ring gear, 14, planet
Power wheel, the 141, first teeth portion, the 142, second teeth portion, 15, support wheel, 151, third teeth portion, the 152, the 4th teeth portion,
16, planet carrier, 2, flexbile gear, 21, interior teeth portion, 3, shell, 4, sun wheel, the 5, first power end, the 6, second power end, A, ring gear are set
Position is arranged in seated position, B, flexbile gear.
Specific embodiment
The utility model is described in further detail in the following with reference to the drawings and specific embodiments, so that those skilled in the art
The utility model may be better understood and can be practiced, but illustrated embodiment is not as the restriction to the utility model.
Shown in referring to Fig.1, an embodiment of the internal tooth flexbile gear speed reducer of the utility model has planetary gear set 1 and flexbile gear
2, it is provided with the first engaging section 11 and the second engaging section 12 in planetary gear set, the ring gear 13 of the first engaging section and planetary gear set connects
It connects, planetary gear set is rotated in ring gear internal messing;Interior teeth portion 21 is provided on flexbile gear inner wall, interior teeth portion and the second engaging section connect
It connects, flexbile gear engagement rotation on planetary gear set periphery;It forms first layer between planetary gear set and ring gear at this time to slow down, i.e. planet
Slow down, and between flexbile gear and planetary gear set formed the second layer slow down, due to flexbile gear interior teeth portion the number of teeth and ring gear the number of teeth not
It is identical, therefore as tooth subtractive speed, and planetary gear set, ring gear form one after cooperating with flexbile gear and merge slowing effect;
By the way that after flexbile gear inner wall is configured interior teeth portion, interior teeth portion is directly engaged with planetary gear set, so that internal tooth
The flute profile in portion can keep standard tooth form, when engaging with planetary gear set, can completely engage, improve joggled strength, increase is held
Carry torsion;And when being rotated in the state of complete engagement, it can be considered that normal gear ring is engaged with gear, maintain rolling friction shape
State reduces gear wear;
And in the elastic foundation that flexbile gear can deform, the interior teeth portion meeting nature of inner wall setting inwardly collects engagement, because
Planetary gear set dimensional tolerance can be absorbed in this, and because flexbile gear is only engaged with the planetary gear set that inside is arranged in, is not present
The position precision problem that flexbile gear external tooth is engaged with ring gear, can reduce part processing precision requirement, while guarantee good defeated
Precision out achievees the effect that back clearance is small, allows lower machining accuracy.
Wherein, planetary gear set includes at least two planetary power wheels 14, the support that the deformation of flexbile gear passes through planetary power wheel
It obtains, planetary power wheel is on the long axis after flexbile gear deformation at this time, and the outer teeth of planetary power wheel and the internal tooth of flexbile gear
Portion's engagement connection can drive flexbile gear to realize rotation when the rotation of planetary power wheel;It only needs to make flexbile gear shape when therefore starting
Become, detent torque is smaller, while not needing deformation bearing to reduce friction, can reduce cost;
And since detent torque is smaller, that is, grip force is smaller, therefore does not need too high reverse input torsion just
It can operate, invertibity improves, and invertibity is preferable.
Above-mentioned planetary gear set, ring gear and flexbile gear can be set in the cavity in shell 3, form effectively opposite position
Fixation is set, shell herein may be bracket etc..
In one embodiment, referring to shown in Fig. 2, the planet carrier 16 of planetary gear set is connect with the first power end 5, on flexbile gear
It is provided with the second power end 6, the first power end can be power input module, i.e. an input shaft, and the input shaft is directly and planet
Frame is fixedly connected, and input shaft rotates planet carrier rotation, and the second power end of drive is power output component, the input of power input module
After power, planet carrier drives planetary power wheel to revolve, and planetary power wheel engages progress with ring gear certainly while revolution
Turn, flexbile gear is driven to be rotated after planetary power wheel rotation;
In this embodiment, due to the presence for not having sun to take turns, it can reduce by one layer of engagement bring teeth processing essence
Degree and teeth wear problem, can be effectively reduced part processing precision requirement, while guaranteeing good output accuracy.
When above structure is without sun wheel, reduction ratio=flexbile gear interior teeth portion number of teeth/flexbile gear the interior teeth portion number of teeth and internal tooth
Enclose the difference of the number of teeth.
In implementing one, referring to shown in Fig. 3 and Fig. 4, sun wheel 4, sun wheel and the first power end 5 are provided among planetary gear set
It connects, the second power end 6 is provided on flexbile gear, the first power end can be power input module, and the second power end is that power is defeated
Component out, after power input module input power, sun wheel rotation cooperatively forms effectively with planetary gear set, ring gear and flexbile gear
Differential teeth planetary slow down, flexbile gear exported by power output component;
Above-mentioned planetary reduction gear ratio=(the ring gear number of teeth/sun tooth number)+1
Tooth subtractive speed ratio=(the interior teeth portion number of teeth/flexbile gear interior teeth portion number of teeth of flexbile gear and the difference of the ring gear number of teeth)
And merge reduction ratio=planetary reduction gear ratio * tooth subtractive speed ratio
It is 80 with the ring gear number of teeth, the planetary gear number of teeth is 30, positive tooth number is 20 and the interior teeth portion number of teeth of flexbile gear is 78
For:
Above-mentioned planetary reduction gear ratio=(80/20)+1=5
Tooth subtractive speed ratio=78/ (78-80)=- 39, negative sign indicate to reversely rotate
Merge reduction ratio=5*-39=-195, negative sign indicates to reversely rotate
In one embodiment, referring to Figure 5, planetary gear set further includes support wheel 15, and the quantity and planet of support wheel are dynamic
The quantity of wheels is consistent, and support wheel is arranged between two adjacent planetary power wheels, and support wheel abutting is arranged in flexbile gear
In teeth portion, the A in figure indicates that position is arranged in ring gear, and B indicates that position is arranged in flexbile gear;Flexbile gear is able to maintain by support wheel to be supported
Tightly, teeth degree of engagement is high, and there is no de- tooth phenomenons;This support wheel is arranged on planet carrier, rotates, that is, is revolved together with planet carrier
Movement, and support wheel is with flexbile gear due to pushing against, under the rotation of flexbile gear, support wheel frictional rotation forms rotation.
Wherein, referring to shown in Fig. 6, support wheel surface can also be arranged third teeth portion 151, third teeth portion and flexbile gear
Interior teeth portion engagement connection, after connecting in such a way that teeth engage, the frictional force between support wheel and flexbile gear is substantially reduced, flexbile gear
It rotates more smooth.
Referring to shown in Fig. 7, the 4th teeth portion 152, the 4th teeth portion and internal tooth can also be arranged in above-mentioned support wheel surface
Circle engagement connection, at runtime, support wheel is engaged with ring gear and flexbile gear interior teeth portion simultaneously, and there is good operation to correct function
Can, and stability is higher when rotating.
In one embodiment, planetary power wheel surface is provided with the first teeth portion 141 and the second teeth portion 142, Duo Gehang
First teeth portion of star power wheel cooperatively forms the first engaging section, and the second teeth portion of multiple planetary power wheels cooperatively forms second
Engaging section;
Wherein, referring to shown in Fig. 8, the teeth quantity in the first teeth portion can be consistent with the teeth quantity in the second teeth portion,
Therefore the corresponding ring gear number of teeth of the first engaging section (i.e. the first layer ring gear number of teeth) ring gear tooth corresponding with the second engaging section
Number is identical (i.e. the second layer ring gear number of teeth, since the application uses flexbile gear, second layer ring gear is an analog component);
Referring to shown in Fig. 9, the teeth quantity in the first teeth portion can be greater than the teeth quantity in the second teeth portion;Its tooth subtractive
Speed ratio can have more variation ranges;
Referring to Fig.1 shown in 0, the teeth quantity in the first teeth portion can be less than the teeth quantity in the second teeth portion;Its tooth is poor
Reduction ratio can have more variation ranges;
Above-mentioned planetary power wheel can change according to the variation of sun wheel, prepare random increase, the scope of application is also big
It is big to improve.
And when using structure described herein preparation, due to the flexbile gear design of internal tooth setting, the assembly zero of speed reducer
Component is reduced, and can be assembled by pure plastic part, and preparation cost is substantially reduced.
Above embodiments are only preferred embodiments for fully illustrating the utility model, the guarantor of the utility model
It is without being limited thereto to protect range.Those skilled in the art made equivalent substitute or transformation on the basis of the utility model,
It is within the protection scope of the utility model.The protection scope of the utility model is subject to claims.
Claims (8)
1. a kind of internal tooth flexbile gear speed reducer, characterized in that it comprises:
Planetary gear set is provided with the first engaging section and the second engaging section in the planetary gear set;
First engaging section of ring gear, the ring gear and planetary gear set connects;
Flexbile gear, is provided with interior teeth portion on the flexbile gear inner wall, and the second engaging section of the interior teeth portion and planetary gear set connects;
And shell, cavity is provided in the shell, the planetary gear set and flexbile gear are arranged in cavity.
2. internal tooth flexbile gear speed reducer as described in claim 1, which is characterized in that the planetary gear set includes at least two planets
Power wheel, the planetary power wheel engage connection with the interior teeth portion of flexbile gear, and the flexbile gear is under the elongate support of planet power wheel
Deformation occurs.
3. internal tooth flexbile gear speed reducer as claimed in claim 2, which is characterized in that the planetary gear set further includes support wheel, institute
The quantity for stating support wheel is consistent with the quantity of planetary power wheel, the support wheel be arranged in two adjacent planetary power wheels it
Between, the support wheel abutting is arranged in the interior teeth portion of flexbile gear.
4. internal tooth flexbile gear speed reducer as claimed in claim 2, which is characterized in that the planetary power wheel surface is provided with first
Teeth portion and the second teeth portion, the first teeth portion of multiple planetary power wheels cooperatively forms the first engaging section, multiple described
Second teeth portion of planetary power wheel cooperatively forms the second engaging section, the teeth quantity in first teeth portion and the second teeth portion
Teeth quantity is consistent or the teeth quantity in the first teeth portion is greater than teeth quantity or the first teeth portion in the second teeth portion
Teeth quantity less than the second teeth portion teeth quantity.
5. internal tooth flexbile gear speed reducer as claimed in claim 3, which is characterized in that the support wheel surface is provided with third teeth
Connection is engaged with the interior teeth portion of flexbile gear by portion, third teeth portion.
6. internal tooth flexbile gear speed reducer as claimed in claim 5, which is characterized in that the support wheel surface is additionally provided with the 4th tooth
Connection is engaged in tooth portion, the 4th teeth portion with ring gear.
7. internal tooth flexbile gear speed reducer as claimed in any one of claims 1 to 6, which is characterized in that set among the planetary gear set
Be equipped with positive wheel, the sun wheel is connect with the first power end, be provided with the second power end on the flexbile gear, first power end with
Second power end is respectively set to power input module and power output component.
8. internal tooth flexbile gear speed reducer as claimed in any one of claims 1 to 6, which is characterized in that the planet of the planetary gear set
Frame is connect with the first power end, and the second power end, first power end and the second power end difference are provided on the flexbile gear
It is set as power input module and power output component.
Priority Applications (1)
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CN201820854061.8U CN208252678U (en) | 2018-06-04 | 2018-06-04 | Internal tooth flexbile gear speed reducer |
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CN201820854061.8U CN208252678U (en) | 2018-06-04 | 2018-06-04 | Internal tooth flexbile gear speed reducer |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108468760A (en) * | 2018-06-04 | 2018-08-31 | 昆山汉升达传动科技有限公司 | Internal tooth flexbile gear speed reducer |
CN110242711A (en) * | 2019-07-16 | 2019-09-17 | 苏州小工匠机器人有限公司 | Planetary reduction gear |
-
2018
- 2018-06-04 CN CN201820854061.8U patent/CN208252678U/en active Active
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108468760A (en) * | 2018-06-04 | 2018-08-31 | 昆山汉升达传动科技有限公司 | Internal tooth flexbile gear speed reducer |
CN110242711A (en) * | 2019-07-16 | 2019-09-17 | 苏州小工匠机器人有限公司 | Planetary reduction gear |
WO2021008060A1 (en) * | 2019-07-16 | 2021-01-21 | 苏州小工匠机器人有限公司 | Planetary decelerator |
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Effective date of registration: 20210111 Address after: 215301 room 2, 33 Yuanfeng Road, Yushan Town, Kunshan City, Suzhou City, Jiangsu Province Patentee after: Suzhou Humeng Transmission Technology Co.,Ltd. Address before: 215316 103-A, 756 Kuntai Road, Kunshan, Suzhou, Jiangsu. Patentee before: KUNSHAN HANSHENGDA TRANSMISSION TECHNOLOGY Co.,Ltd. |
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