CN203892472U - Closed cycloid precise speed reducer - Google Patents

Abstract

The utility model discloses a closed cycloid precise speed reducer, comprising an input part, a needle tooth shell, an output part and a few tooth difference inner meshing speed reducing mechanism; needle tooth pins for meshing with a cycloid wheel of the few tooth difference inner meshing speed reducing mechanism are peripherally arrayed at the inner ring of the needle tooth shell; containing slots which correspond to the needle tooth pins one by one and are used for mounting the needle tooth pins are arranged at the inner ring of the needle tooth shell; the needle tooth pins and inner walls of the corresponding containing slots are in dual-line contact. According to the closed cycloid precise speed reducer, the needle tooth pins and the corresponding containing slots on the pin tooth shell have dual-line contact characteristic, the needle tooth pins and the containing slots are in dual-line contact in the width direction, the bending strength is enlarged and the bearing capacity is increased; meanwhile, the error homogenizing effect can be favorably played due to the increment of contact lines, the transmission precision is improved and the demands on machining errors and assembly errors are reduced; compared with the existing RV speed reducer, the closed cycloid precise speed reducer has the advantages that the return difference is small, the structure is compact, the service life is long, the machining process is simple and the manufacturing cost is low.

Description

Closed Cycloidal Precision Reducer

technical field

The utility model relates to the technical field of cycloid reducers, in particular to a closed cycloid precision reducer.

Background technique

At present, RV reducers for high-precision robots in China mainly rely on imports, and are monopolized by Japan's Nabtesco. The RV reducers produced by this company have high transmission accuracy, high torsional rigidity, small hysteresis, strong impact resistance, and high efficiency. However, advanced special equipment is required to process the cycloidal gear profile and the pin hole of the pin gear housing, and the process system is complex, and the cycloidal gear profile and the pin hole of the pin gear housing are sensitive to machining errors. In order to obtain a small backlash and make the load evenly distributed, The manufacturing precision is very high. It is precisely because of the high-precision processing requirements of the existing structure of the RV reducer that the product cost is very high, and the current processing level in our country is difficult to meet this precision requirement.

In addition, the half-buried gear structure of the RV reducer without pin gear sleeve is to half bury the pin gear pin in the pin hole of the pin gear housing. Although the problem of bending deformation of the pin gear pin is solved, the existing machining accuracy cannot fully guarantee the pin hole. The consistency between the inner diameter and the outer diameter of the pintooth pin, usually the inner diameter of the pin hole is slightly larger than the outer diameter of the pintooth pin, there is a gap between the pintooth pin and the pinhole of the pintooth housing and a single-line contact occurs, and the hysteresis caused by this part of the error is not easy to control , and the single-line contact is not conducive to the rotation of the pin-toothed pin around its central axis, causing sliding friction between the pin-toothed pin and the cycloidal wheel, resulting in increased temperature rise and reduced transmission efficiency.

Therefore, in order to solve the above problems, it is necessary to improve the existing cycloidal pinwheel reducer, reduce the requirements for high-precision manufacturing through structural design, and propose a motor with smaller hysteresis, compact structure and longer service life than the existing RV reducer. A cycloidal pinwheel reducer has simple processing technology and low manufacturing cost.

Utility model content

In view of this, the purpose of this utility model is to provide a closed cycloidal precision reducer, which reduces the requirements for high-precision processing and manufacturing through structural design, and is smaller than the existing RV reducer. The processing technology is simple and the manufacturing cost is low.

The closed type cycloidal precision reducer of the utility model includes an input part, a needle-tooth housing, an output part, and an internal meshing deceleration mechanism with a small-tooth difference. The gear pins meshed with the cycloidal wheel of the meshing reduction mechanism, the inner ring of the gear housing and the pin gear pins are provided with a containment groove for installing the pin gear pins in one-to-one correspondence; the pin tooth pins are in double-line contact with the inner wall of the corresponding containment groove ;

Further, the containment groove is formed by wire cutting with a wire cutting machine;

Further, the shape of the containment groove is a double-arc discontinuous curve, the pin tooth pin is installed in the double-arc containment groove of the pin gear housing, and the two arc lines on the shaft section meet the outer circle of the pin tooth pin at a contact angle α. cut, the pin tooth pin and the containment groove are in double-line contact;

Further, the contact angle α≥θ _max , K ₁ ——Short width coefficient of cycloidal wheel, K ₁ =ez _b /R _Z ; e——Eccentric distance; Z _b ——Number of pin gear teeth, that is, the number of pin pins; R _z ——Radius of pin wheel; and The double-arc radius r _n of the containment groove and the pin tooth pin radius r _z satisfy λ=r _n /r _z , λ=1.04～1.1; the inner hole diameter D _n of the pin gear housing increases to D _z +(0.2～0.4) , D _z is the diameter of the pin tooth pin distribution circle; the sharp corners on both sides of the containment groove adopt rounded transition;

Further, the shape of the containment groove is a parabolic continuous smooth curve;

Further, the output part includes an output disc that is coaxially rotated with the cycloidal wheel through a pin-hole transmission and is connected to the pin-tooth case with a single degree of freedom; The left end plate and the right end plate connected together; the left end plate and the pin gear housing and between the right end plate and the pin gear housing are both axially and radially bidirectionally supported and rotated;

Further, radial bearing rollers and axial bearing rollers are provided between the left end disc and the pin gear housing and between the right end disc and the pin gear housing, and the axial ends of the pin gear housing correspond to the radial bearing rollers and the axial bearing rollers. The axial bearing rollers are respectively provided with an outer raceway with a rib on one side; the corresponding radial bearing rollers and axial bearing rollers of the left end disc and the right end disc are respectively provided with an inner raceway with a rib on the other side; The left end plate and the right end plate are also fixed with cages corresponding to the radial bearing rollers;

Further, cross roller bearings, angular contact bearings or tapered roller bearings can be respectively arranged between the left end disk and the pinion housing and between the right end disk and the pinion housing to realize axial and radial two-way support and rotation connection;

Further, the input part includes an input gear shaft; the internal gear reduction mechanism with small tooth difference includes an involute planetary gear, a cycloidal wheel, and a crankshaft; the involute planetary gear is connected with the input gear shaft as a sun gear A first-stage involute planetary reduction mechanism is formed; the crankshaft and the involute planetary gear are set in one-to-one correspondence; the crankshaft axle is coaxially fixed with the corresponding involute planetary gear and is connected to the left end disc and the single-degree-of-freedom rotation The right end plate; the eccentric wheel of the crankshaft and the cycloid wheel are arranged in one-to-one correspondence and used as a rocker arm to cooperate with the corresponding cycloid wheel to drive the cycloid wheel to roll along the inner ring of the pin wheel formed by the pin tooth pin to form the second stage. Cycloidal pin wheel planetary reduction mechanism; the eccentric wheel and the cycloidal wheel are rotated through the integrated double eccentric bearing with the eccentric wheel as the inner ring and the cycloidal wheel as the outer ring. The outer circular surface is equipped with an integrated double eccentric bearing raceway with a single-side rib. The integrated double eccentric bearing raceway is filled with cylindrical rollers. The axial movement of the cylindrical roller is limited; the cycloidal wheel and the output part form a simply supported pin-shaft output mechanism through the pin hole transmission; the tooth profile of the cycloidal wheel is a cycloidal tooth profile with a given meshing clearance, which forms The process is:

a. Obtain the initial clearance; select the single-side tooth profile of the cycloid wheel as the research object, and change the standard tooth profile of the cycloid wheel obtained by the standard tooth profile equation of the cycloid wheel by changing the pin radius r _z , the pin wheel radius R _z or At the same time, change the size of the two to obtain the initial gap, and obtain the curve I of the single-side tooth profile of the cycloid wheel. The tooth profile equation of the curve I is as follows:

b. Rotate the curve I; take the inflection point (x ₀ , y ₀ ) of the curve I as the center, and rotate an angle α to obtain the curve II; the coordinates of the inflection point (x ₀ , y ₀ ):

The tooth profile equation of curve Ⅱ:

x ₂ ＝x ₀ +(x ₁ -x ₀ )cosα+(y ₁ -y ₀ )sinα

y ₂ =y ₀ -(x ₁ -x ₀ )sinα+(y ₁ -y ₀ )cosα

c. Deflection curve II; taking the origin of the cycloid wheel coordinate system as the center, deflect the curve II by an angle β to obtain curve III, which is the single-side tooth profile curve of the cycloid wheel with a given meshing clearance; the tooth profile of curve III equation:

x ₃ ＝x ₂ cosβ+y ₂ sinβ

y ₃ ＝-x ₂ sinβ+y ₂ cosβ

d. Transition arc (addendum circle)

Addendum circle radius:

when hour, the maximum value of is the radius of the transition arc addendum circle;

Transition arc equation:

$\begin{array}{c}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; aMax</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\\ {\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; aMax</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\end{array}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; \&theta;</span>}<span\; class="notranslate">\; \&Element;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; )</span>$

exist , the backlash-free meshing tooth profile intersects the transition arc, and the simultaneous equations can be solved to obtain θ _t

${\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&pi;</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; \&pi;</span>}}{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}}<span\; class="notranslate">\; ;</span>$

The tooth profile equation of cycloidal gear with meshing clearance is:

x ₂ ＝x ₀ +(x ₁ -x ₀ )cosα+(y ₁ -y ₀ )sinα

y ₂ =y ₀ -(x ₁ -x ₀ )sinα+(y ₁ -y ₀ )cosα

x ₃ ＝x ₂ cosβ+y ₂ sinβ

Among the above formulas, when can be obtained when that is initial value;

—— the final value of

- the meshing limit point of pin tooth pin;

K ₁ ——Short-width coefficient of the cycloid wheel, K ₁ = ez _b /R _Z ;

i ^H ——the relative transmission ratio of the cycloid wheel and the pin wheel, i ^H ＝z _b /z _g ;

——The rotation angle of the rotary arm relative to the center vector of a pin tooth, that is, the meshing phase angle;

r _z ——pin outer circle radius;

R _z —— pin wheel radius;

ΔR _z ——the amount of change in the radius of the pin wheel;

Δr _z ——the amount of change in pin radius;

α——the rotation angle of curve I with the inflection point (x ₀ , y ₀ ) as the center;

β——deflection angle of curve II;

e - eccentricity;

Z _b ——the number of teeth of the pin wheel, that is, the number of pins;

Z _g ——The number of cycloid gear teeth.

The beneficial effects of the utility model are: the enclosed cycloid precision reducer of the utility model has a double-line contact characteristic between the pintooth pin and the containment groove on the pintooth shell, and the pintooth pin and the containment groove in the tooth width direction are Double-line contact increases the bending strength and load capacity. At the same time, the increase of the contact line is conducive to exerting the error averaging effect and improving the transmission accuracy, thereby reducing the requirements for processing errors and assembly errors; it is slower than the existing RV The device has small hysteresis, compact structure, long service life, simple processing technology and low manufacturing cost.

Description of drawings

Fig. 1 is the structural representation of the utility model;

Fig. 2 is the left view of Fig. 1;

Fig. 3 is a schematic diagram of the structure of a double-arc containment tank;

Fig. 4 is a schematic diagram of the structure of a parabolic containment tank;

Figure 5 is a comparison diagram of the cycloid tooth profile of the standard tooth profile of the cycloid wheel and the cycloid tooth profile of the given meshing clearance;

Figure 6 is an enlarged view of the axial and radial two-way support and rotation connection structure;

Figure 7 is an enlarged view of the integrated double eccentric bearing;

Fig. 8 is an assembly diagram of the combination of radial bearing rollers and axial bearing rollers used in the present invention;

Fig. 9 is an assembly drawing of the cross roller bearing applied in the utility model;

Fig. 10 is an assembly drawing of the utility model using angular contact bearings and tapered roller bearings.

Detailed ways

Fig. 1 is a schematic structural view of the present utility model; Fig. 2 is a left view of Fig. 1; Fig. 3 is a schematic structural view of a double-arc containment groove; Fig. 4 is a schematic structural view of a parabolic containment groove; Fig. 5 is a standard tooth profile of a cycloid wheel The comparison diagram of the cycloid tooth profile with the given meshing clearance; Figure 6 is an enlarged view of the axial and radial two-way support and rotation connection structure; Figure 7 is an enlarged view of the integrated double eccentric bearing; Figure 8 is the application of the utility model to the radial bearing roller The assembly diagram of the roller and axial bearing roller combination; Figure 9 is the assembly diagram of the utility model application cross roller bearing; Figure 10 is the assembly diagram of the utility model application angular contact bearing and tapered roller bearing; as shown in the figure : The enclosed cycloidal precision reducer of the present embodiment includes an input part, a pin gear housing 1, an output part and an internal meshing deceleration mechanism with a small tooth difference, and the inner circle of the pin gear housing 1 is circumferentially arranged for use with the few teeth The pin tooth pin 3 meshed with the cycloid wheel 2 of the tooth difference internal meshing reduction mechanism, the pin tooth pin 3 is arranged along the inner ring of the pin gear housing 1 and fixed to form a pin wheel, and the inner ring of the pin gear housing 1 corresponds to the pin gear pin 3 one by one There is a containment groove 4 for installing the pintooth pin 3; the pintooth pin 3 is in double-line contact with the inner wall of the corresponding containment groove 4; the double-line contact is that the pointer tooth pin 3 passes through its two generatrices and the containment groove in the tooth width direction 4. Contact; the bending strength is increased, the bearing capacity is improved, and the increase of the contact line is conducive to exerting the error homogenization effect and improving the transmission accuracy, thereby reducing the requirements for processing errors and assembly errors; at the same time, the positioning of the pin tooth pin 3 is reliable , the hysteresis is small, the transmission precision is high, its rotation around its own axis is flexible, and it is not easy to form a dead point. The wear of the tooth surface of the pin tooth pin 3 is relatively uniform, which is conducive to improving the transmission efficiency; the bottom of the containment groove 4 does not contact the pin tooth pin 3 , can hold a part of lubricating grease and dirt, reduce wear and tear, and improve the smoothness of pin tooth pin 3 rotation.

In this embodiment, the containment groove 4 is formed by wire cutting with a slow-moving wire cutting machine; when processing a reducer with a smaller diameter pin tooth pin 3, the surface roughness of the containment groove 4 is good, the machining accuracy is high, and the manufacturing cost is low. Low.

In this embodiment, the shape of the containment groove 4 is a double-arc discontinuous curve, the pintooth pin 3 is installed in the double-arc containment groove 4 of the pintooth housing 1, and the two arc lines on the shaft section are aligned with the pintooth pin 3 The outer circle is tangent at the contact angle α, so the pin-tooth pin 3 and the containment groove 4 are in double-line contact; the shape of the containment groove 4 is a double-arc discontinuous curve, which means that the cross-sectional curve of the containment groove 4 is connected by two arc curves Forming, as shown in FIG. 3 , a double-line contact is produced between the two cylindrical surfaces corresponding to the two arc curves and the pin tooth pin 3 .

In this embodiment, the contact angle α≥θ _max , K ₁ ——Short width coefficient of cycloidal wheel 2, K ₁ =ez _b /R _Z ; e——eccentric distance; Z _b ——Number of pin gear teeth, that is, the number of 3 pin pins; R _z ——Pin wheel radius , the radius of the pin wheel is the radius of the pin tooth pin distribution circle; and the double arc radius r _n of the containment groove 4 and the radius r _z of the pin tooth pin 3 satisfy λ=r _n /r _z , λ=1.04～1.1; the pin tooth housing 1 The inner hole diameter D _n increases to D _z + (0.2 ~ 0.4), D _z is the distribution circle diameter of the pin tooth pin 3; the sharp corners on both sides of the containment groove 4 adopt rounded transition, and the sharp corners on both sides of the containment groove 4 are rounded Treatment can prevent stress concentration, facilitate oil intake and the formation of lubricating oil film, improve lubrication characteristics, and thus improve transmission efficiency.

In this embodiment, the shape of the containment tank 4 is a parabolic continuous smooth curve; the shape of the containment tank 4 is a parabolic continuous smooth curve means that the cross-sectional curve of the containment tank 4 is a parabolic continuous smooth curve, as shown in Figure 4, the parabola The two-part curved surfaces on both sides of the vertex are in double-line contact with the pin tooth pin 3; the inner surface of the containing groove 4 is a continuous smooth curved surface, which is beneficial to processing and lubrication.

In this embodiment, the output part includes an output disk that cooperates with the cycloidal wheel 2 through pin-hole transmission and is coaxially rotated with a single degree of freedom and is connected to the pin-tooth housing 1; The left end plate 5 and the right end plate 6 fixedly connected to each other in the axial direction; between the left end plate 5 and the pin gear housing 1 and between the right end plate 6 and the pin gear housing 1 are both axially and radially bidirectionally supported Rotational connection; a simply supported pin shaft output mechanism is formed. The double support structure of the simply supported pin shaft output mechanism makes the reducer rigid and functionally symmetrical, and can achieve coaxial bidirectional output. Compared with the cantilever shaft type in the prior art The structure of the output mechanism is more stable; the axial and radial two-way supporting and rotating connection structure enables the reducer to bear radial load and large axial load at the same time in a small space.

In this embodiment, radial bearing rollers 7 and axial bearing rollers 8 are provided between the left end disc 5 and the pinion housing 1 and between the right end disc 6 and the pinion housing 1, and the pinion housing 1 shaft The two ends correspond to the radial bearing rollers 7 and the axial bearing rollers 8, respectively, with outer raceways with one side rib; the left end disk 5 and the right end disk 6 correspond to the radial bearing rollers 7 and the axial bearing rollers 8 are respectively provided with an inner raceway with a rib on the other side; the left end disk 5 and the right end disk 6 are also fixed with a cage 9 corresponding to the radial bearing roller 7; as shown in Figure 8, the radial bearing roller 7 refers to the bearing roller whose axis is arranged radially along the pin gear housing 1; the axial bearing roller 8 refers to the bearing roller whose axis is arranged axially along the pin gear housing 1, and the rib on one side and the rib on the other side are The shoulder retaining surfaces provided at the axial ends of the radial bearing roller 7 and the axial bearing roller 8 are used for axial positioning of the corresponding radial bearing roller 7 or axial bearing roller 8; the radial bearing roller The sub 7 is arranged on the inner side of the axial bearing roller 8, that is, the axial bearing roller 8 points to the inner side of the pin gear housing 1; the axial bearing roller 8 is arranged on the outer side of the radial bearing roller 7, that is, the radial The bearing roller 7 points outward along the radial direction of the pin gear housing 1. The radial bearing roller 7 and the axial bearing roller 8 form an angle of 90°. The inner raceway is located between the radial bearing roller 7 and the axial bearing roller 7. The inner raceway of the 90° included angle between the bearing rollers 8, the outer raceway is the outer raceway located at the 90° included angle between the radial bearing roller 7 and the axial bearing roller 8; The processing and assembly of disc 5, right end disc 6 and pin gear housing 1 are reasonably designed.

In this embodiment, cross roller bearings 10, angular contact bearings 11 or tapered roller bearings 12 can be respectively arranged between the left end disk 5 and the pinion housing 1 and between the right end disk 6 and the pinion housing 1 to realize axial , radial two-way support rotation connection; Figure 9 is the assembly drawing of the utility model application of the cross roller bearing 10; Figure 10 is the assembly drawing of the utility model application of the angular contact bearing 11 and the tapered roller bearing 12, and the application of the cross roller bearing 10. The angular contact bearing 11 or tapered roller bearing 12 can make full use of existing resources, reduce manufacturing costs, and facilitate assembly and maintenance.

In this embodiment, the input part includes an input gear shaft 13; the internal gear reduction mechanism with small tooth difference includes an involute planetary gear 14, a cycloidal wheel 2 and a crankshaft 15; the involute planetary gear 14 is The input gear shaft 13 is connected to the sun gear to form a first-stage involute planetary reduction mechanism; the crankshaft 15 is set in one-to-one correspondence with the involute planetary gear 14; the wheel shaft 15a of the crankshaft 15 is connected to the corresponding involute planetary gear 14 is coaxially fixed and connected to the left end disc 5 and the right end disc 6 in a single degree of freedom rotation; the eccentric wheel 15b of the crankshaft 15 is set in one-to-one correspondence with the cycloid wheel 2 and is used as a rocker arm to rotate and cooperate with the corresponding cycloid wheel 2 Drive the cycloidal wheel 2 to roll along the inner ring of the pin wheel formed by the pin tooth pin 3 to form a second-stage cycloidal pin wheel planetary reduction mechanism; The cycloidal wheel 2 is an integrated double eccentric bearing 16 with full complement of cylindrical rollers formed by the outer ring for rotation fit, wherein the outer surface of the eccentric wheel 15b is provided with an integrated double eccentric bearing raceway with a single side rib, the integrated double eccentric bearing The raceway of the eccentric bearing is filled with cylindrical rollers, and the other side of the cylindrical rollers is installed on the eccentric wheel 15b by the back-up ring 17 using the shrink-fit process to limit the axial movement of the cylindrical rollers; the cycloidal wheel 2 and the output part pass through the pin hole The transmission cooperates to form a simply supported pin shaft type output mechanism; the input gear shaft 13, the pin gear housing 1, the left end plate 5 and the right end plate 6 are arranged coaxially, the involute planetary gear 14, the cycloid wheel 2, and the crank shaft 15 The axis is parallel to the axes of the input gear shaft 13, the pin gear housing 1, the left end disc 5 and the right end disc 6; the integrated double eccentric bearing 16 adopts the structural design of the full complement roller bearing, which has the advantages of small size, compact structure and large bearing capacity. Long service life and other advantages; the tooth profile of the cycloidal wheel 2 is a cycloidal tooth profile with a given meshing gap, and its formation process is:

a. Obtain the initial gap; select the unilateral tooth profile of the cycloidal wheel 2 as the research object, and the unilateral tooth profile is the tooth profile between the tooth top of the cycloidal wheel 2 and the bottom of the nearest alveolar slot; The standard tooth profile of the cycloidal wheel obtained by the standard tooth profile equation of the linear wheel 18 is obtained by changing the radius r _z of the pin tooth pin 3, the radius R _z of the pin wheel or both, and the initial clearance is obtained, where the radius R _z of the pin wheel is the pin tooth pin 3 Radius of the distribution circle; the curve Ⅰ of the tooth profile on one side of the cycloid wheel 2 is obtained, and the tooth profile equation of the curve Ⅰ is as follows:

b. Rotate the curve I; take the inflection point (x ₀ , y ₀ ) of the curve I as the center, and rotate an angle α to obtain the curve II; the coordinates of the inflection point (x ₀ , y ₀ ):

The tooth profile equation of curve Ⅱ:

x ₂ ＝x ₀ +(x ₁ -x ₀ )cosα+(y ₁ -y ₀ )sinα

y ₂ =y ₀ -(x ₁ -x ₀ )sinα+(y ₁ -y ₀ )cosα

c. Deflection curve II; take the origin of the cycloidal wheel 2 coordinate system as the center, and the origin of the cycloidal wheel 2 coordinate system is the geometric center of the cycloidal wheel 2, that is, the center of the cycloidal wheel 2, and deflect the curve II by an angle β , to obtain the curve III, which is the given meshing clearance cycloid tooth profile 19; the tooth profile equation of the curve III:

x ₃ ＝x ₂ cosβ+y ₂ sinβ

y ₃ ＝-x ₂ sinβ+y ₂ cosβ

d. Transition arc (addendum circle)

Addendum circle radius:

when hour, the maximum value of is the radius of the transition arc addendum circle;

Transition arc equation:

$\begin{array}{c}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; aMax</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\\ {\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; aMax</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\end{array}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; \&theta;</span>}<span\; class="notranslate">\; \&Element;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; )</span>$

exist , the backlash-free meshing tooth profile intersects the transition arc, and the simultaneous equations can be solved to obtain θ _t

${\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&pi;</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; \&pi;</span>}}{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}}<span\; class="notranslate">\; ;</span>$

The tooth profile equation of cycloid wheel 2 with meshing gap is:

x ₂ ＝x ₀ +(x ₁ -x ₀ )cosα+(y ₁ -y ₀ )sinα

y ₂ =y ₀ -(x ₁ -x ₀ )sinα+(y ₁ -y ₀ )cosα

x ₃ ＝x ₂ cosβ+y ₂ sinβ

Among the above formulas, when can be obtained when that is initial value;

—— the final value of

——The meshing limit point of pintooth pin 3, that is, the meshing limit point of the meshing point (contact point) on the tooth profile of pintooth pin 3 when the cycloid wheel 2 teeth mesh with pintooth pin 3;

K ₁ ——Cycloid wheel 2 short width coefficient, K ₁ = ez _b /R _Z ;

i ^H ——the relative transmission ratio of cycloid wheel 2 and pin wheel, i ^H =z _b /z _g ;

——The rotation angle of the rotating arm relative to the center vector of a pin tooth pin 3, that is, the meshing phase angle;

r _z ——pin tooth pin 3 outer circle radius;

R _z —— pin wheel radius;

ΔR _z ——the amount of change in the radius of the pin wheel;

Δr _z ——the amount of change in the radius of pin tooth pin 3;

α——the rotation angle of curve I with the inflection point (x ₀ , y ₀ ) as the center;

β——deflection angle of curve II;

e - eccentricity;

Z _b ——the number of pin gear teeth, that is, the number of 3 pin pins;

Z _g - the number of teeth of the cycloidal wheel 2;

The standard tooth profile equation of the cycloid wheel is:

A cycloidal tooth profile with a given meshing clearance is adopted. This new tooth profile is modified based on transmission accuracy maintenance and load capacity optimization. Compared with the standard cycloidal tooth profile, the economical machining accuracy is low and the transmission accuracy is easy to guarantee. Direct access to tooth top clearance and tooth bottom clearance.

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present utility model without limitation. Although the utility model has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the utility model can be Modifications or equivalent replacements of the technical solutions without departing from the purpose and scope of the technical solutions of the utility model shall be covered by the claims of the utility model.

Claims (9)

1. A closed cycloidal precision reducer, characterized in that it includes an input part, a pin gear housing, an output part, and an internal meshing deceleration mechanism with a small tooth difference, and the inner ring of the pin gear housing is arranged circumferentially for contact with the Pintooth pins meshed with the cycloidal gear of the internal meshing reduction mechanism with less tooth difference, the inner ring of the pintooth housing and the pintooth pins are provided with a containment groove for installing the pintooth pins one by one; the pintooth pins and the corresponding containment grooves Two-wire contact on the inner wall. the 2. The enclosed cycloidal precision reducer according to claim 1, characterized in that: the containment groove is formed by wire cutting with a wire cutting machine. the 3. The enclosed cycloidal precision reducer according to claim 1, characterized in that: the shape of the containment groove is a double-arc discontinuous curve, the pin tooth pin is installed in the double-arc containment groove of the pin gear housing, and the shaft Two arc lines on the cross-section are tangent to the outer circle of the pin-toothed pin at the contact angle α, so the pin-toothed pin and the containing groove are in double-line contact. the 4. The enclosed cycloid precision reducer according to claim 3, characterized in that: the contact angle α≥θ _max , K ₁ ——Short width coefficient of cycloidal wheel, K ₁ =ez _b /R _Z ; e——Eccentric distance; Z _b ——Number of pin gear teeth, that is, the number of pin pins; R _z ——Radius of pin wheel; and The double-arc radius r _n of the containment groove and the pin tooth pin radius r _z satisfy λ=r _n /r _z , λ=1.04～1.1; the inner hole diameter D _n of the pin gear housing increases to D _z +(0.2～0.4) , D _z is the diameter of the pin distribution circle; the sharp corners on both sides of the containment groove adopt rounded transition. 5. The enclosed cycloid precision reducer according to claim 1, characterized in that: the shape of the containing groove is a parabolic continuous smooth curve. the 6. The enclosed cycloidal precision reducer according to claim 1, characterized in that: the output part includes an output that cooperates with the cycloidal wheel through a pin-hole transmission and is connected to the pinion housing for coaxial rotation with a single degree of freedom disk; the output disk includes a left end disk and a right end disk which are arranged at both axial ends of the pin tooth housing and fixed together; between the left end disk and the pin tooth housing and between the right end disk and the pin tooth housing are Axial and radial two-way support rotation connection. the 7. The enclosed cycloidal precision reducer according to claim 6, characterized in that radial bearing rollers and shafts are arranged between the left end disc and the pin gear housing and between the right end disc and the pin gear housing To the bearing roller, the axial ends of the pin gear housing correspond to the radial bearing roller and the axial bearing roller are respectively provided with an outer raceway with one side rib; the left end plate and the right end plate correspond to the radial bearing roller and the shaft The radial bearing rollers are respectively provided with inner raceways with ribs on the other side; the left end disk and the right end disk are also fixed with cages corresponding to the radial bearing rollers. the 8. The enclosed cycloidal precision reducer according to claim 6, characterized in that: between the left end plate and the pin gear housing and between the right end plate and the pin gear housing, cross roller bearings, angular contact Bearings or tapered roller bearings realize axial and radial two-way support and rotation connection. the 9. The enclosed cycloidal precision reducer according to any one of claims 1-8, characterized in that: the input part includes an input gear shaft; the internal meshing reduction mechanism with small tooth difference includes an involute planet gear, cycloid wheel and crank shaft; the involute planetary gear is connected with the input gear shaft as the sun gear to form a first-stage involute planetary reduction mechanism; the crank shaft and the involute planetary gear are set in one-to-one correspondence ; The wheel shaft of the crankshaft is coaxially fixed with the corresponding involute planetary gear and connected to the left end disk and the right end disk with a single degree of freedom rotation; The rotation of the wheel is used to drive the cycloid wheel to roll along the inner ring of the pin wheel formed by the pin tooth pin to form a second-stage cycloid pin wheel planetary reduction mechanism; the eccentric wheel and the cycloid wheel are passed through the eccentric wheel The cycloidal wheel is an integrated double eccentric bearing with full complement of cylindrical rollers formed by the outer ring. The outer circular surface of the eccentric wheel is provided with an integrated double eccentric bearing raceway with a single side rib, and the integrated double eccentric bearing roll The road is full of cylindrical rollers, and the other side of the cylindrical rollers is installed on the eccentric wheel by the shrink-fit process to restrict the axial movement of the cylindrical rollers; the cycloidal wheel and the output part are matched by pin hole transmission to form simply supported pins. Axial output mechanism; the tooth profile of the cycloidal wheel is a cycloidal tooth profile with a given meshing gap, and its formation process is: a. Obtain the initial clearance; select the single-side tooth profile of the cycloid wheel as the research object, and change the standard tooth profile of the cycloid wheel obtained by the standard tooth profile equation of the cycloid wheel by changing the pin radius r _z , the pin wheel radius R _z or At the same time, change the size of the two to obtain the initial gap, and obtain the curve I of the single-side tooth profile of the cycloid wheel. The tooth profile equation of the curve I is as follows: b. Rotate the curve I; take the inflection point (x ₀ , y ₀ ) of the curve I as the center, and rotate an angle α to obtain the curve II; the coordinates of the inflection point (x ₀ , y ₀ ): The tooth profile equation of curve Ⅱ: x ₂ ＝x ₀ +(x ₁ -x ₀ )cosα+(y ₁ -y ₀ )sinα y ₂ =y ₀ -(x ₁ -x ₀ )sinα+(y ₁ -y ₀ )cosα c. Deflection curve II; taking the origin of the cycloid wheel coordinate system as the center, deflect the curve II by an angle β to obtain curve III, which is the single-side tooth profile curve of the cycloid wheel with a given meshing clearance; the tooth profile of curve III Equation: x ₃ ＝x ₂ cosβ+y ₂ sinβ y ₃ ＝-x ₂ sinβ+y ₂ cosβ d. Transition arc (addendum circle) Addendum circle radius: when hour, the maximum value of is the radius of the transition arc addendum circle; Transition arc equation: exist , the backlash-free meshing tooth profile intersects the transition arc, and the simultaneous equations can be solved to obtain θ _t The tooth profile equation of cycloidal gear with meshing gap is: x ₂ ＝x ₀ +(x ₁ -x ₀ )cosα+(y ₁ -y ₀ )sinα y ₂ =y ₀ -(x ₁ -x ₀ )sinα+(y ₁ -y ₀ )cosα x ₃ ＝x ₂ cosβ+y ₂ sinβ y ₃ =-x ₂ sinβ+y ₂ cosβ, Among the above formulas, when can be obtained when that is initial value; the final value of - the meshing limit point of pin tooth pin; K ₁ ——Short-width coefficient of the cycloid wheel, K ₁ = ez _b /R _Z ; i ^H ——the relative transmission ratio of the cycloid wheel and the pin wheel, i ^H ＝z _b /z _g ; ——The rotation angle of the rotary arm relative to the center vector of a pin tooth, that is, the meshing phase angle; r _z ——pin outer circle radius; R _z —— pin wheel radius; ΔR _z ——the amount of change in the radius of the pin wheel; Δr _z ——the amount of change in pin radius; α——the rotation angle of curve I with the inflection point (x ₀ , y ₀ ) as the center; β——deflection angle of curve II; e - eccentricity; Z _b ——the number of teeth of the pin wheel, that is, the number of pins; Z _g ——The number of cycloid gear teeth.