CN207485986U - A kind of planetary gear and the RV retarders of crank axle interference fit - Google Patents
A kind of planetary gear and the RV retarders of crank axle interference fit Download PDFInfo
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- CN207485986U CN207485986U CN201721013129.1U CN201721013129U CN207485986U CN 207485986 U CN207485986 U CN 207485986U CN 201721013129 U CN201721013129 U CN 201721013129U CN 207485986 U CN207485986 U CN 207485986U
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- planetary gear
- crank axle
- positioning
- retarders
- hole
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Abstract
The utility model is related to a kind of planetary gears and the RV retarders of crank axle interference fit, the RV retarders include central gear and multiple planetary gears and multiple crank axles, multiple planetary gears are sequentially connected with the central gear, mounting hole is offered in the middle part of the planetary gear, the crank axle passes through the mounting hole, and be interference fitted with the planetary gear, the planetary gear and crank axle are arranged in a one-to-one correspondence.The utility model installs planetary gear with crank axle by the way of interference fit, without being attached using traditional spline pair, it no longer needs to prepare high-precision spline process tool, the spline problem on deformation brought without the concern for heat treatment, it does not need to carry out roll flute positioning to planetary gear using relative complex splined shaft tooling, it does not need to carry out crank axle circumferentially positioned, it does not need to carry out crank axle using relative complex spline hole tool eccentric segment grinding positioning, therefore difficulty of processing is reduced, simplifies cutter, technique and tooling.
Description
Technical field
The RV being interference fitted the utility model is related to retarder technical field more particularly to a kind of planetary gear with crank axle subtracts
Fast device.
Background technology
RV retarders are a kind of precision speed reduction devices being widely used on industrial robot, as depicted in figs. 1 and 2, it
It is made of involute cylindrical gear planetary gear speed reducing mechanism and cycloid pin gear planet speed reducer structure two parts.Involute cylindrical gear row
Star deceleration mechanism is made of central gear 1, planetary gear 2 and planet carrier 7.Cycloid pin gear planet speed reducer structure is by crank axle 3, needle tooth
4th, the first Cycloidal Wheel 5, the second Cycloidal Wheel 6 and pin wheel housing 8 form.Planetary gear 2 is linked to be one with crank axle 3 by spline pair 21
Body, the input as cycloid pin gear planet speed reducer structure.First Cycloidal Wheel 5 and the second Cycloidal Wheel 6 will be moved by crank axle 3 to be passed
Pass planet carrier 7.Central gear 1 is the input terminal of RV retarders, and planet carrier 7 is the output terminal of RV retarders.
In the structure of RV retarders, in order to meet the transmission accuracy requirement of RV retarders and assembling requirement, each planet
2 requirement of wheel has higher consistency each other, and each crank axle 3 requires have higher consistency each other.In the prior art, due to
Planetary gear 2 is connected with crank axle 3 by spline pair 21, so needing to meet following requirement:
1. the phase relation that the spline tooth of each planetary gear 2 should be in a circumferential direction consistent with its gear teeth;For example, flower
Key teeth and gear teeth are symmetrical about vertically symmetrical line simultaneously, i.e., in a circumferential direction, spline tooth has specific with gear teeth
Phase relation, this phase relation should be consistent on all planetary gears 2;
2. the spline tooth of each crank axle 3 should be closed with the phase that the eccentric direction of crank axle 3 is consistent in a circumferential direction
System;For example, the eccentric direction of crank axle 3, along vertically symmetrical line, the spline tooth socket on crank axle 3 is symmetrical about vertically symmetrical line,
I.e. in a circumferential direction, the eccentric direction of spline tooth and crank axle 3 has specific phase relation, this phase relation is all
It should be consistent on crank axle 3.
Therefore, in order to keep the consistency of each planetary gear 2 and each crank axle 3, high-precision spline processing knife need to be equipped with
Tool avoids spline deformation caused by being heat-treated, and carries out roll flute positioning to planetary gear 2 using special splined shaft tooling or adopt
Spline is processed after heat treatment with special tool, and eccentric segment is carried out to crank axle 3 using special spline hole tool
Grinding positioning.Each of which increases difficulty of processing, and high requirement is proposed to process tool, tooling and technique.
Utility model content
Technical problem to be solved in the utility model is in view of the deficiencies of the prior art, to provide a kind of planetary gear and crank
The RV retarders of axis interference fit, to solve at least one of above-mentioned technical problem.
The technical solution that the utility model solves above-mentioned technical problem is as follows:A kind of planetary gear and crank axle interference fit
RV retarders, the RV retarders include central gear and multiple planetary gears and multiple crank axles, multiple planetary gears with it is described
Central gear is sequentially connected, and offers mounting hole in the middle part of the planetary gear, and the crank axle passes through the mounting hole, and with institute
Planetary gear interference fit is stated, the planetary gear and crank axle are arranged in a one-to-one correspondence.
The beneficial effects of the utility model are:The utility model by planetary gear and crank axle using by the way of being interference fitted into
Row installation, without being attached using traditional spline pair, it is no longer necessary to prepare high-precision spline process tool, not need to examine
Consider the spline problem on deformation that heat treatment is brought, do not need to determine planetary gear progress roll flute using relative complex splined shaft tooling
Position does not need to be circumferentially positioned to crank axle progress, does not need to carry out crank axle using relative complex spline hole tool eccentric
Section grinding positioning, therefore difficulty of processing is reduced, simplify cutter, technique and tooling.
Based on the above technical solution, the utility model can also do following improvement.
Further, the crank axle passes through one end of the mounting hole to be sequentially formed with positioning cylinder and interference section, described
Planetary gear is interference fitted with the interference section, and cricoid circlip groove, institute are offered between the positioning cylinder and the interference section
It states and circlip is provided in circlip groove, the circlip is bonded with the planetary gear close to the side of the positioning cylinder.
Further, one end outer sheath of the interference section far from the positioning cylinder is equipped with abutment sleeve, the positioning sleeve
Cylinder is bonded with side of the planetary gear far from the positioning cylinder.
Advantageous effect using above-mentioned further scheme is:One end of crank axle is respectively set to positioning cylinder and interference
Section by setting abutment sleeve in one end of positioning cylinder, positions the installation of planetary gear, and then by interference section and planet
Wheel interference fit, and further stable and limiting plays the planetary gear after installation using circlip.
Further, the circlip groove is formed with to guide the planetary gear on the side side wall of the interference section
Guide chamfering.
Advantageous effect using above-mentioned further scheme is:Guiding is opened up on side side wall of the circlip groove close to interference section
When installing planetary gear, guiding role is played to planetary gear, is conducive to the assembling of planetary gear for chamfering.
Further, the planetary gear and the crank axle are 3, and the center composition one of 3 planetary gears is equilateral
Triangle.
Further, it is offered for the circumferentially positioned positioning through hole of the planetary gear and use on each planetary gear
In the tapped through hole for dismantling the planetary gear, the positioning through hole and tapped through hole are respectively positioned on the outside of the mounting hole.
Advantageous effect using above-mentioned further scheme is:Due to eliminating spline structure, using positioning through hole to planet
Wheel progress is circumferentially positioned, and can be coordinated with positioning tool, to ensure that the assembly direction of multiple planetary gears is consistent;And
Being threaded through-hole can be convenient for disassembling planetary gear from RV retarders.
Further, the tapped through hole for dismantling the planetary gear, the screw thread are offered on each planetary gear
Through-hole is respectively positioned on the outside of the mounting hole.
Further, the tapped through hole on each planetary gear is two, and two tapped through holes are about institute
The center for stating planetary gear is centrosymmetric.
Advantageous effect using above-mentioned further scheme is:Tapped through hole is opened up on planetary gear, is being needed planetary gear
When being unloaded on crank axle, planetary gear can be removed by the cooperation of auxiliary tool and tapped through hole, two centers pair are set
The tapped through hole of title can make the uniform force of planetary gear, easy to disassemble.
Further, it further includes for the planetary gear to be installed to the positioning tool on the crank axle, the positioning work
Dress includes matrix and the multiple positioning pins being arranged on matrix, and the positioning pin is set perpendicular to described matrix, each row
It is offered on star-wheel for the positioning through hole circumferentially positioned to the planetary gear, positioning pin cloth corresponding with positioning through hole
It puts, and the number of the positioning pin is identical with the number of the planetary gear.
Advantageous effect using above-mentioned further scheme is:When being installed to planetary gear, using positioning tool to row
Star-wheel progress is circumferentially positioned, multiple positioning pins is inserted respectively into positioning through hole, it can be ensured that the assembling side of multiple planetary gears
To consistent.
Further, described matrix includes three connecting rods, and one end of three connecting rods is fixed together, adjacent
Angle between two connecting rods is 120 °, and the positioning pin is three, and three positioning pins are separately positioned on three
The other end of the connecting rod.
Further, the positioning through hole on each planetary gear is two, and two positioning through hole are about institute
The center for stating planetary gear is centrosymmetric.
Description of the drawings
Fig. 1 is the transmission schematic diagram of RV retarders in background technology;
Fig. 2 is the structure chart of RV retarders in background technology;
Fig. 3 is the structure diagram that planetary gear is connect with crank axle spline in background technology;
Fig. 4 is the structure chart of RV retarders described in the utility model;
Fig. 5 is the assembling explosive view of planetary gear and crank axle described in the utility model;
Fig. 6 is the structure diagram of planetary gear described in the utility model;
Fig. 7 is the structure diagram of positioning tool described in the utility model;
Fig. 8 is the structure chart for assembling planetary gear in the utility model using the positioning tool.
In attached drawing, parts list represented by the reference numerals are as follows:
1st, central gear;2nd, planetary gear;21st, spline pair;22nd, mounting hole;23rd, positioning through hole;24th, tapped through hole;3rd, it is bent
Arbor;31st, positioning cylinder;32nd, circlip groove;321st, circlip;33rd, interference section;34th, abutment sleeve;4th, needle tooth;5th, the first pendulum
Line wheel;6th, the second Cycloidal Wheel;7th, planet carrier;8th, pin wheel housing;9th, positioning tool;91st, matrix;911st, connecting rod;92nd, positioning pin.
Specific embodiment
The principle and feature of the utility model are described below in conjunction with attached drawing, example is served only for explaining this practicality
It is novel, it is not intended to limit the scope of the utility model.
As Figure 4-8, a kind of planetary gear of the utility model and the RV retarders of crank axle interference fit, the RV subtract
Fast device includes central gear 1 and multiple planetary gears 2 and multiple crank axles 3, multiple planetary gears 2 are driven with the central gear 1
Connection, the middle part of the planetary gear 2 offer mounting hole 22, and the crank axle 3 passes through the mounting hole 22, and with the planet
3 interference fit of wheel, the planetary gear 2 and crank axle 3 are arranged in a one-to-one correspondence.
In the prior art, RV retarders are the precision speed reduction devices being widely used on industrial robot.It is existing into
The component construction of type, mainly by central gear 1 as power intake, by involute cylindrical gear planetary gear speed reducing mechanism and cycloid
The gearing of pinwheel planetary gear speed reducing mechanism coordinates to realize function and effect.Crank axle 3 is on cycloid pin gear planet speed reducer structure
One component, planetary gear 2 is a component on involute cylindrical gear planetary gear speed reducing mechanism, between crank axle 3 and planetary gear 2
The gearing of Liang Ge mechanisms is realized by spline pair 21.
In the utility model, planetary gear 2 is installed with crank axle 3 by the way of interference fit, without adopting
It is attached with traditional spline pair 21, it is no longer necessary to prepare high-precision spline process tool, without the concern for heat treatment band
The spline problem on deformation come is not needed to carry out roll flute positioning to planetary gear 2 using relative complex splined shaft tooling, not needed to pair
Crank axle 3 carries out circumferentially positioned, and it is fixed not need to carry out crank axle 3 using relative complex spline hole tool eccentric segment grinding
Position, therefore reduces difficulty of processing, simplifies cutter, technique and tooling, meanwhile, time of processing is also saved, saving is known clearly
Production cost.
As shown in figure 5, the crank axle 3 passes through one end of the mounting hole 22 to be sequentially formed with positioning cylinder 31 and interference
Section 33, the planetary gear 2 is interference fitted with the interference section 33, is offered between the positioning cylinder 31 and the interference section 33
Cricoid circlip groove 32 is provided with circlip 321 in the circlip groove 32, and the circlip 321 is leaned on the planetary gear 2
The side fitting of the nearly positioning cylinder 31.Wherein, positioning cylinder 31 is located at the end of crank axle 3, and the interference section 33 is separate
One end outer sheath of the positioning cylinder 31 be equipped with abutment sleeve 34, the planetary gear 2 be located at the abutment sleeve 34 with it is described
Between circlip 321, the abutment sleeve 34 is bonded with side of the planetary gear 2 far from the positioning cylinder 31.Positioning
The setting of cylinder 31 and abutment sleeve 34 can when mounted position planetary gear 2, make side and the positioning of planetary gear 2
Sleeve 34 is bonded, and opposite side is bonded with circlip 321, can play certain stabilization and limiting to the planetary gear 2 after installation
Effect.And by planetary gear 2 and interference section 33 using being interference fitted, abandon previous spline connection.Such setting has such as
Under benefit:
1. for planetary gear 2, due to eliminating spline structure, no longer need to prepare high-precision spline processing
Cutter without the concern for the spline problem on deformation that heat treatment is brought, is not needed to using relative complex splined shaft tooling to planet
Wheel carries out roll flute positioning, therefore reduces difficulty of processing, simplifies cutter, technique and tooling;
2. for crank axle 3, due to eliminating spline structure, it is no longer necessary to it is circumferentially positioned, therefore no longer need standard
Standby high-precision spline process tool without the concern for the spline problem on deformation that heat treatment is brought, is not needed to using relative complex
Spline hole tool eccentric segment grinding positioning is carried out to crank axle, therefore reduce difficulty of processing, simplify cutter, technique and work
Dress;
In addition, it is formed with to guide planetary gear 2 on the side side wall of the interference section 33 in the circlip groove 32
Guiding chamfering.Guiding chamfering is opened up on side side wall of the circlip groove 32 close to interference section 33, it is right when installing planetary gear 2
Planetary gear 2 plays guiding role, is conducive to the assembling of planetary gear 2.
As shown in fig. 6, it is offered on each planetary gear 2 of the utility model for circumferential to the planetary gear 2
The positioning through hole 23 of positioning and the tapped through hole 24 for dismantling the planetary gear 2, the positioning through hole 23 and tapped through hole 24
It is respectively positioned on the outside of the mounting hole 22.It is circumferentially positioned to planetary gear progress using positioning through hole due to eliminating spline structure,
And can be coordinated with positioning tool 9, to ensure that the assembly direction of multiple planetary gears 2 is consistent;And it is threaded through-hole
24 can be convenient for disassembling planetary gear 2 from RV retarders.
As shown in fig. 6, in a specific embodiment of the utility model, it is preferred that the positioning through hole and described
Tapped through hole is two, and two positioning through hole are centrosymmetric about the center of the planetary gear, two screw threads
Through-hole is centrosymmetric about the center of the planetary gear.
As Figure 7-8, in order to facilitate the installation of planetary gear 2 with it is circumferentially positioned, be additionally provided with for by the planetary gear 2
The positioning tool 9 being installed on the crank axle 3.The positioning tool 9 includes matrix 91 and is arranged on multiple on matrix 91
Positioning pin 92, the positioning pin 92 are set perpendicular to described matrix 91, the arrangement corresponding with positioning through hole 23 of positioning pin 92, and
The number of the positioning pin 92 is identical with the number of the planetary gear 2.When being installed to planetary gear 2, using positioning tool 9
Planetary gear 2 is carried out circumferentially positioned, multiple positioning pins 92 are inserted respectively into positioning through hole 23, it can be ensured that multiple planetary gears
2 assembly direction is consistent.
As Figure 4-8, in a specific embodiment of the utility model, the planetary gear 2 and the crank axle 3
It it is 3, the center of 3 planetary gears 2 forms an equilateral triangle, and be distributed in the outside of the central gear 1.It is excellent
Choosing, the matrix 91 of the positioning tool 9 includes three connecting rods 911, and one end of three connecting rods 911 is fixedly connected on
Together, the angle between adjacent two connecting rods 911 is 120 °.The positioning pin 92 is three, three positioning pins
92 are separately positioned on the other end of three connecting rods 911.In this way when being positioned to planetary gear 2, each positioning pin can
To be placed in a planetary gear 2 positioning through hole, it is ensured that the assembly direction of each planetary gear 2 is consistent, so as to ensure that row
Star-wheel 2 and central gear 1 can correct engagements.
The assembly method of RV retarders that a kind of planetary gear of the utility model is interference fitted with crank axle is:Planetary gear 2
When being installed on crank axle 3, each planetary gear 2 is radially positioned on positioning cylinder 31 first, then using positioning tool 9 to each
A planetary gear 2 carry out it is circumferentially positioned, by the corresponding positioning for being inserted into 3 planetary gears 2 respectively of 3 positioning pins 91 of positioning tool 9
It in through-hole 23, reuses press mounting tool and each planetary gear 2 is pressed into interference section 33, axis bullet is finally packed into circlip groove 32
Property baffle ring 321.
The above is only the preferred embodiment of the present invention, is not intended to limit the utility model, all in this practicality
Within novel spirit and principle, any modification, equivalent replacement, improvement and so on should be included in the guarantor of the utility model
Within the scope of shield.
Claims (10)
1. the RV retarders of a kind of planetary gear and crank axle interference fit, the RV retarders include central gear (1) and multiple
Planetary gear (2) and multiple crank axles (3), multiple planetary gears (2) are sequentially connected with the central gear (1), which is characterized in that
Mounting hole (22) is offered in the middle part of the planetary gear (2), the crank axle (3) across the mounting hole (22), and with it is described
Planetary gear (2) is interference fitted, and the planetary gear (2) and crank axle (3) are arranged in a one-to-one correspondence.
2. a kind of planetary gear according to claim 1 and the RV retarders of crank axle interference fit, which is characterized in that described
One end of crank axle (3) across the mounting hole (22) is sequentially formed with positioning cylinder (31) and interference section (33), the planet
It takes turns (2) to be interference fitted with the interference section (33), ring-type is offered between the positioning cylinder (31) and the interference section (33)
Circlip groove (32), circlip (321), the circlip (321) and the planet are provided in the circlip groove (32)
(2) are taken turns to be bonded close to the side of the positioning cylinder (31).
3. a kind of planetary gear according to claim 2 and the RV retarders of crank axle interference fit, which is characterized in that described
Interference section (33) far from the positioning cylinder (31) one end outer sheath be equipped with abutment sleeve (34), the abutment sleeve (34) with
Side of the planetary gear (2) far from the positioning cylinder (31) is bonded.
4. a kind of planetary gear according to claim 2 and the RV retarders of crank axle interference fit, which is characterized in that described
Circlip groove (32) is formed with to fall for guiding the guiding of the planetary gear (2) on the side side wall of the interference section (33)
Angle.
5. a kind of planetary gear according to claim 1 and the RV retarders of crank axle interference fit, which is characterized in that described
Planetary gear (2) and the crank axle (3) are 3, and the center of 3 planetary gears (2) forms an equilateral triangle.
6. a kind of planetary gear according to claim 1 and the RV retarders of crank axle interference fit, which is characterized in that each
The tapped through hole (24) for dismantling the planetary gear (2) is offered on the planetary gear (2), the tapped through hole (24) is equal
Positioned at the outside of the mounting hole (22).
7. a kind of planetary gear according to claim 6 and the RV retarders of crank axle interference fit, which is characterized in that each
The tapped through hole (24) on the planetary gear (2) is two, and two tapped through holes (24) are about the planetary gear
(2) center is centrosymmetric.
8. according to the RV retarders that a kind of planetary gear of claim 1-7 any one of them and crank axle are interference fitted, feature
It is, further includes for the planetary gear (2) to be installed to the positioning tool (9) on the crank axle (3), the positioning tool
(9) including matrix (91) and the multiple positioning pins (92) being arranged on matrix (91), the positioning pin (92) is perpendicular to the base
Body (91) is set, and is offered for the positioning through hole circumferentially positioned to the planetary gear (2) on each planetary gear (2)
(23), the positioning pin (92) arrangement corresponding with the positioning through hole (23), and the number of the positioning pin (92) and the row
The number of star-wheel (2) is identical.
9. a kind of planetary gear according to claim 8 and the RV retarders of crank axle interference fit, which is characterized in that described
Matrix (91) includes three connecting rods (911), and one end of three connecting rods (911) is fixed together, adjacent two
Angle between the connecting rod (911) is 120 °, and the positioning pin (92) is three, and three positioning pins (92) set respectively
Put the other end in three connecting rods (911).
10. a kind of planetary gear according to claim 8 and the RV retarders of crank axle interference fit, which is characterized in that every
The positioning through hole (23) on a planetary gear (2) is two, and two positioning through hole (23) are about the planet
The center of wheel (2) is centrosymmetric.
Priority Applications (1)
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CN201721013129.1U CN207485986U (en) | 2017-08-14 | 2017-08-14 | A kind of planetary gear and the RV retarders of crank axle interference fit |
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CN201721013129.1U CN207485986U (en) | 2017-08-14 | 2017-08-14 | A kind of planetary gear and the RV retarders of crank axle interference fit |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107387708A (en) * | 2017-08-14 | 2017-11-24 | 国机智能技术研究院有限公司 | A kind of planetary gear and the RV decelerators of crank axle interference fit |
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2017
- 2017-08-14 CN CN201721013129.1U patent/CN207485986U/en active Active
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107387708A (en) * | 2017-08-14 | 2017-11-24 | 国机智能技术研究院有限公司 | A kind of planetary gear and the RV decelerators of crank axle interference fit |
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