The harmonic gear transmission device of PFPE and Ag solid lubricating film mixed lubrication
Technical field
The invention belongs to transmission device fields, are related to a kind of suitable for harmonic gear transmission device under the conditions of various working
PFPE and Ag solid lubricating film mixed lubrication technology more particularly to a kind of PFPE and Ag solid lubricating film mixed lubrication it is humorous
Wave gear assembly.
Background technique
With conventional gear transmission ratio, harmonic gear transmission device has big transmission ratio, small in size, light weight and transmission accuracy
The advantages that high.Harmonic gear transmission device is belonged to using the flexible deformation of flexbile gear come passing movement and power, firm gear and flexbile gear cooperation
In no sideshake squash type fit system, the failure mode of harmonic gear transmission device is mainly shown as in harmonic gear transmission device
Each contact area lubricating status in portion is bad to cause flexbile gear and firm gear teeth portion to wear, so as to cause the gradually decline of transmission performance.
Currently, the lubricating system of harmonic gear transmission device mostly uses lubricating grease in the market, there is good viscosity temperature characteristic
And greasy property, but under the operating condition that temperature increases and load increases, the efficiency of grease lubrication harmonic gear transmission device can go out
Existing a degree of decline;And harmonic gear transmission device is usually used in the working condition of low speed, underloading.The grease of low-speed running
Effective lubricating oil film cannot be formed between lubrication friction pair and the adhesive wear of teeth portion is caused to be harmonic gear transmission device master
Want failure cause.
That there are coefficient of frictions if only with solid lubrication mode is larger, heat-conductive characteristic is poor and solid lubrication rouge is reviewed one's lessons by oneself
Renaturation poor can all influence its lubricating life.
Existing other patents use the pure WS of magnetron sputtering method preparation2Thin film coated to harmonic wave flexbile gear and firm gear teeth portion, and
Mixed lubrication is used for together with lubricating grease.Although WS2The thickness control accuracy of film is high, is able to satisfy the higher of dimensional accuracy and wants
It asks;But leads to that bearing capacity is low, friction durability is short since hardness itself is low, and easily deliquesced in atmosphere wet environment and oxygen
Change, reduces its solid lubrication performance and friction durability.
Summary of the invention
It is an object of the invention to overcome the deficiencies in the prior art, and provide a kind of PFPE and mix with Ag solid lubricating film
The harmonic gear transmission device of lubrication, it is intended to which the fretting wear for reducing flexbile gear and firm gear improves making for harmonic gear transmission device
Use the service life.
Specific technical solution of the present invention is as follows:
A kind of harmonic gear transmission device of PFPE and Ag solid lubricating film mixed lubrication, including firm gear, flexbile gear, flexibility
Bearing and wave producer;Flexible bearing is assembled on the wave producer, flexible bearing is externally provided with flexbile gear;The flexbile gear generates controllable
Flexible deformation, and be meshed with firm gear for passing movement and power;The teeth portion surface of the firm gear and flexbile gear is covered with one layer of Ag
Solid lubricating film, and Ag solid lubricating film surface is coated with PFPE lubricating grease;The basis material of the firm gear is spheroidal graphite casting
Iron;The basis material of the flexbile gear is 38Cr2Mo2VA steel alloy;The basis material of the flexible bearing is bearing steel;The ball
The heat treatment process of black cast iron is isothermal hardening;The 38Cr2Mo2The heat treatment process of VA steel alloy is modifier treatment and induction
Quenching.The spheroidal graphite cast-iron is graphite with cast iron existing for balled form.
The isothermal quenching technique of above-mentioned nodular cast iron is specially that nodular cast iron after molding is heated to 900 DEG C to make its Ovshinsky
Body simultaneously homogenizes, and is allowed to be as cold as 300 DEG C of bainite transformation temperature section fastly, then salt bath isothermal holding 30 minutes, austenite
It is changed into air-cooled after bainite, its hardness reaches HRC40 after means of isothermal quenching.Above-mentioned 38Cr2Mo2The modifier treatment of VA steel alloy
And impewdance matching specifically: first by 38Cr after molding2Mo2VA steel alloy quenches at 850 DEG C, uses cooling medium for oil,
Tempering temperature is 590 degree, and hardness reaches 32HRC after modifier treatment;Then impewdance matching is carried out, using high-frequency induction hardening, frequency
Rate is 300KHZ, cold, the depth of hardening zone 0.6mm of oil, and flexbile gear teeth portion surface hardness reaches HRC48 after impewdance matching.
Further preferably, the inside and outside loop material of flexible bearing is GCr15.
The heat treatment process of basis material also will affect the binding force of itself and Ag solid lubricant film.Firm gear is to use continuously casting
Spheroidal graphite cast-iron hollow profile, it is reachable with the binding force critical load Pc of Ag solid lubricant film by means of isothermal quenching
980N;Flexbile gear uses 38Cr2Mo2After VA steel alloy, modifier treatment and impewdance matching, face with the binding force of Ag solid lubricant film
Boundary load p c is up to 1471N.
Preferably, the manufacturing process of the Ag solid lubricating film is multi-arc ion plating process.
Preferably, the thickness of the Ag solid lubricating film is greater than 0um and is less than 5um.
Further preferably, the thickness of the Ag solid lubricating film is greater than 0um and is less than 1um.
Preferably, the wave producer and flexbile gear inner wall surface are uniformly coated by PFPE lubricating grease.
Preferably, the viscosity index (VI) of the PFPE lubricating grease is higher than 300.Flexbile gear and firm gear teeth portion Ag solid are moistened respectively
Sliding film surface is lubricated processing using PFPE lubricating grease, guarantees that teeth portion is in service life and is in PFPE lubrication shape
State.PFPE lubricating grease is greatly increased with the retarder service life under Ag solid lubricant film mixed lubricating state.
Preferably, the tooth profile parameter of the harmonic gear transmission device is as follows:
Firm gear pressure angle α 1=14 ° 36 ', modulus m=0.3, flexbile gear pressure angle α 2=14 ° 36 ', addendum coefficient ha*=
0.5, radial clearance coefficient c*=0.4;Flexbile gear tooth form uses bicircular arcs tooth form, and flexbile gear teeth directional is at the both ends close to bottom of a cup and rim of a cup
There are low-angle α cone angles;The low-angle α cone angle is less than 1 °.Such tooth Shape Design helps to promote harmonic gear transmission device
Load-carrying properties and precision stability, realize harmonic gear transmission device complete machine long-life operation.
Preferably, the tooth number Z of the firm gear1=202;The tooth number Z of flexbile gear2=200;Reduction ratio i=100.
Preferably, the parameter of multi-arc ion plating process is as follows: ion bombardment rate is 5~20W;Bottom vacuum degree is less than 1Pa;
Ar partial pressure is 0.1~5Pa;Multi-arc ion plating process electric current is 60~120A;Sedimentation time is 5~30min.
Further preferably, the parameter of multi-arc ion plating process is as follows: ion bombardment rate is 11W;Bottom vacuum degree be 5.5 ×
10-3Pa;Ar partial pressure is 0.8Pa;Multi-arc ion plating process electric current is 90A;Sedimentation time is 10min.
Ag solid lubricating film is under this condition with a thickness of 0.8um.And Ag solid lubricating film and 38Cr2Mo2VA steel alloy
Coefficient of friction is that the coefficient of friction of 0.03, Ag solid lubricating film and firm gear basis material spheroidal graphite cast-iron is 0.06.After tested, this
When Ag solid lubrication thin critical load P >=18N, bearing capacity w >=6GPa.Using PFPE lubricating grease respectively to flexbile gear and firm gear tooth
Portion's Ag film surface is lubricated processing.It is thin mixed with PFPE lubricating grease solid-liquid in Ag solid lubrication that harmonic speed reducer is probed by test
Close the friction factor under lubricating status.Friction factor when the input speed of input terminal is 1500r/min, between firm gear and flexbile gear
It is 0.038.When output end load is 10Nm, input speed is 3r/min, retarder transmission efficiency be greater than 50% the case where
Under, the service life of device is up to 6000h.
The present invention in terms of existing technologies, has the advantages that
1) compared to the lubricating system only with lubricating grease, one layer of Ag solid lubricating film is coated in flexbile gear and firm gear teeth portion
Friction surface lacks the shortcomings that adsorbed film is protected caused by lubricating grease supply deficiency can be efficiently solved.And the present invention adopts
Use Ag as solid lubrication rouge, Ag has the characteristics that shear strength is low, thermal coefficient is high, can prevent or reduce firm gear and flexbile gear
Contact between matrix reduces coefficient of friction and surface temperature.Ag solid lubricating film has oneself of similar high viscosity fluid simultaneously
Repair function, rupture occurs in solid film can carry out auto-mending under external load function.
2) the viscosity-temperature index analysis for comparing different lubricating grease can effectively lower temperature to lubrication shape using PFPE lubricating grease
The influence of state.Simultaneously under the conditions of having grease lubrication, when surface lubrication state is changed into boundary lubrication condition, soft metal layer
Double protection can be played to matrix surface together with lubricating oil.
3) with common WS2Solid lubricating film basis material is compared, and difference can be used in the preparation of Ag solid lubricating film
Preparation process, sedimentary condition, according to it is different need prepare be suitble to requirements films.In the present invention, Ag solid lubrication is thin
Film can reach that teeth portion thin film coated is uniform, and thickness is smaller than 1um by multi sphere ion plating technology.Meanwhile with flexbile gear matrix
38Cr2Mo2The coefficient of friction of VA steel alloy is 0.03, and the coefficient of friction with firm gear matrix ductile cast iron is 0.06, coefficient of friction
It is 1/10th or so of metal friction coefficient when not doing coating.In addition, flexbile gear and firm gear basis material are through Overheating Treatment
Hardness can reach HRC40~48 afterwards, and Ag solid lubricating film and basis material binding force under this condition are very big, at this time Ag solid
The bearing capacity of composite lubricating film is relatively high.WS is used in comparison2The harmonic gear drive of solid lubricating film mixed lubrication mode, is adopted
There is longer service life with the harmonic gear drive of Ag solid lubricating film mixed lubrication mode, transmission efficiency is greater than
50% service life is opposite that about 1500h can be improved up to 6000h.It is mixed using Ag solid lubricating film and under high input speed
The firm gear and flexbile gear coefficient of friction for closing the harmonic gear drive of lubricating system, which are far below, uses WS2Solid lubricating film mixed lubrication
The harmonic gear drive of mode.
Detailed description of the invention
Fig. 1 is harmonic gear transmission device schematic diagram;
Fig. 2 flexbile gear and firm gear teeth portion mesh schematic representation;
Fig. 3 flexbile gear and firm gear teeth portion engage enlarged drawing;
Fig. 4 multi-arc ion coating Ag solid lubricating film schematic diagram;
Fig. 5 is Ag solid lubricating film and PFPE lubricating grease solid-liquid mixing lubrication scheme schematic diagram;
Fig. 6 is harmonic gear transmission device firm gear and flexbile gear coefficient of friction testing result under three kinds of different lubricating ways;
Fig. 7 is that transmission efficiency detection is tied in harmonic gear transmission device accelerated life test under three kinds of different lubricating ways
Fruit.
Specific embodiment
The present invention is further elaborated and is illustrated with reference to the accompanying drawings and detailed description.Each implementation in the present invention
The technical characteristic of mode can carry out the corresponding combination under the premise of not conflicting with each other.
Harmonic gear transmission device is as shown in Figure 1, the wherein flexible bearing outer ring in wave producer and the interference of flexbile gear inner ring
Cooperate lower continuous rotation, flexbile gear constantly deforms and repeat between firm gear engaging-in-engage-nibbling out-disengagement-engaging-in
Cyclic process.During firm gear and flexbile gear gear pair are intermeshed, sliding friction occurs between the flank of tooth and rubs with rolling
It wipes.
In the preferred embodiment, select SHXB-CSF25-100 type harmonic gear transmission device as modeling.
In this embodiment, the firm gear tooth number Z 1=202 of harmonic gear transmission device, flexbile gear tooth number Z 2=200 slow down
Compare i=100.And in order to promote the load-carrying properties of harmonic gear transmission device and precision stability, harmonic gear transmission is realized
Long-life of device complete machine runs, and tooth curve uses common tangent double circular arc tooth outline, and flexbile gear teeth directional is close to bottom of a cup and rim of a cup
There are 1 ° of cone angles of low-angle α < at both ends.Firm gear pressure angle α 1=14 ° 36 ', modulus m=0.3, flexbile gear pressure angle α 2=14 ° 36 ',
Addendum coefficient ha*=0.5, radial clearance coefficient c*=0.4.Flexbile gear and firm gear teeth portion be all completed by gear hobbing process, and
It is handled through too strong spray, flexbile gear and the engagement of firm gear teeth portion are as shown in Figures 2 and 3.
In this embodiment, flexbile gear and firm gear teeth portion are using multi-arc ion plating process plated film.As shown in figure 4, being state
The AS710DTXB multi sphere ion multi-arc ion plating process machine that interior relevant enterprise provides carries out the schematic diagram of multi-arc ion coating.Multi sphere
Ion plating purpose is that plating one layer of Ag solid uniform and that thickness is greater than 0um less than 5um in flexbile gear and firm gear teeth portion moistens
Synovial membrane.For various sizes of flexbile gear and firm gear, required technological parameter is also different, and its parameter need to be in certain model
Enclose interior adjustment.Such as ion bombardment rate is 5~20W;Bottom vacuum degree is less than 1Pa;Ar partial pressure is 0.1~5Pa;Multi-arc ion coating work
Skill electric current is 60~120A;Sedimentation time is 5~30min.
In the present embodiment, used parameter is as follows: ion bombardment rate is 11W, and background vacuum is 5.5 × 10-3Pa,
Ar partial pressure is 0.8Pa, and multi-arc ion plating process electric current is 90A, sedimentation time 10min.It can guarantee that Ag is solid under this technological parameter
Body lubricating film is uniform in flexbile gear and firm gear the teeth portion coating of SHXB-CSF25-100 type harmonic gear transmission device.In this condition
Under, flexbile gear and firm gear teeth portion Ag solid lubrication film thickness average out to 0.8um.
For same matrix material, different heat treatment process early period will affect its hardness.And flexbile gear and firm gear
Basis material use different heat treatment methods, the binding force of Ag solid lubricant film and basis material can also occur obviously to become
Change.Therefore, most preferred heat treatment process in order to obtain, has studied influence of the different heat treatment technique to hardness and binding force.
As shown in table 1, through testing, nodular cast iron uses isothermal hardening, and specific process parameter is by ball milling after molding
Cast iron, which is heated to 900 DEG C, to be made its austenitizing and homogenizes, and is allowed to be as cold as 300 DEG C of bainite transformation temperature section fastly, then salt
Bath isothermal holding 30 minutes, austenite are changed into air-cooled after bainite, its hardness reaches HRC40 after means of isothermal quenching.
38Cr2Mo2VA steel alloy uses modifier treatment and impewdance matching, specific process parameter are as follows: first to after molding
38Cr2Mo2VA steel alloy quenches at 850 DEG C, uses cooling medium for oil, tempering temperature is 590 degree, hardness after modifier treatment
Reach 32HRC;Then impewdance matching is carried out, using high-frequency induction hardening, frequency 300KHZ, oil is cold, and depth of hardening zone is
0.6mm, flexbile gear teeth portion surface hardness reaches HRC48 after impewdance matching.As a comparison, only with the 38Cr of modifier treatment2Mo2VA's
Flexbile gear hardness is only HRC32, and the spheroidal graphite cast-iron of modifier treatment is only HRC25.In addition, after heat treatment, basis material and Ag solid
The binding force of lubricating film is also greatly improved.Using rockwell indentation method to combine force estimation it is found that by modifier treatment and
The 38Cr of impewdance matching processing2Mo2The critical load Pc=1471N of VA flexbile gear, and the spheroidal graphite cast-iron Jing Guo means of isothermal quenching is rigid
The critical load Pc=980N of wheel.And through detecting pure Ag solid lubrication membrane coat and flexbile gear basis material 38Cr2Mo2VA alloy
The coefficient of friction of steel is up to 0.03, and the coefficient of friction with firm gear basis material spheroidal graphite cast-iron is up to 0.06.
Therefore, in this embodiment, firm gear basis material uses the spheroidal graphite cast-iron hollow profile of continuously casting, and spheroidal graphite is cast
Iron need to carry out means of isothermal quenching;Flexbile gear basis material uses 38Cr2Mo2VA steel alloy, and 8Cr2Mo2VA steel alloy is adjusted
Matter processing and impewdance matching;Flexible bearing Internal and external cycle and rolling element basis material use GCr15 bearing steel.
The binding force critical load of Ag solid lubricant film and flexbile gear, firm gear under 1 different heat treatment mode of table
According to the adhesive wear mould under the harmonic gear transmission device mixed lubricating state of the propositions such as Wang Jiaxu, Li Junyang
Type, in low-speed running, temperature and load are affected to harmonic gear transmission device lubricating status.PFPE lubricating grease viscosity refers to
Number can be higher than 300, and low temperature coefficient of friction is very low, can effectively lower influence of the temperature to lubricating status.So using viscosity
PFPE lubricating grease of the index higher than 300 is lubricated coating to harmonic gear transmission device flexbile gear and firm gear teeth portion, such as Fig. 5 institute
Show, metal surface 1 is firm gear teeth portion, and metal surface 2 is flexbile gear teeth portion, and solid lubricant film 3 is Ag solid lubricant film, hydrodynamic lubrication
Rouge 4 is PFPE lubricating grease.
At room temperature, friction-wear test is carried out to the present invention treated harmonic gear transmission device.Pass through monitoring driving
The variation of power input to a machine (being characterized with the voltage of driving motor) and harmonic gear transmission device temperature rise, investigates harmonic gear
The lubricating status of transmission device is made an uproar when the moment of friction of harmonic gear transmission device significantly increases and supervenes apparent friction
When sound, it is determined as lubrication failure.Fig. 6 is harmonic gear transmission device firm gear and flexbile gear coefficient of friction under three kinds of different lubricating ways
Detection, in the case that testing result can be seen that input terminal 1500r/min, PFPE lubricating grease and Ag solid lubricant film mixed lubrication
Coefficient of friction in the harmonic gear transmission device of processing between firm gear and flexbile gear is the humorous of 0.038, PFPE grease lubrication processing
Coefficient of friction between wave gear assembly firm gear and flexbile gear reach 0.066, WS2 film and PFPE grease lubrication processing it is humorous
Coefficient of friction between wave gear assembly firm gear and flexbile gear reaches 0.055.Moreover, with the raising of input speed, Ag is solid
The advantage of body lubricating film and PFPE lubricating grease mixed lubrication is more obvious, substantially less than uses WS2Solid lubricant film and PFPE profit
The mode of consistent lubricant mixed lubrication.
Fig. 7 is transmission efficiency detection in harmonic gear transmission device accelerated life test under three kinds of different lubricating ways, defeated
6000 hours of the harmonic gear transmission device model machine of outlet load 10Nm, input speed 3r/min are run the examination of machine fatigue life
Test testing result to show: the main failure forms of harmonic gear transmission device are the gradually decline of transmission efficiency, PFPE lubricating grease
Service life of the harmonic gear transmission device transmission efficiency greater than 50% with the processing of Ag solid lubricant film mixed lubrication is up to 6000h.
Compared to using WS2The harmonic gear drive of solid lubricating film mixed lubrication mode, service life can promote about 1500h.
Above-mentioned embodiment is only a preferred solution of the present invention, so it is not intended to limiting the invention.Have
The those of ordinary skill for closing technical field can also make various changes without departing from the spirit and scope of the present invention
Change and modification.Therefore all mode technical solutions obtained for taking equivalent substitution or equivalent transformation, all fall within guarantor of the invention
It protects in range.