CN205534041U - Two -stage harmonic planetary gear reducer - Google Patents

Abstract

The utility model relates to a two -stage harmonic planetary gear reducer, including setting up at the internal wave generator who is used for receiving power of reductor, wave generator is last from interior flexbile gear and the circular spline of outwards cup jointing in proper order, forms first order harmonic gear drive mechanism, flexbile gear coaxial coupling sun gear, reductor body front end sets up the motor interface, and circular spline fixed mounting is on motor interface inner wall, going back integrative being provided with on the internal wall of reductor and encircleing at the outside internal gear of sun gear, be provided with the planet wheelset between sun gear and the internal gear, the planet carrier that all connections are used for output power is taken turns to every planet in the planet wheelset, forms second level planetary gear. The utility model discloses first order harmonic gear drive mechanism can improve the drive ratio of reduction gear, and simultaneously, the utility model discloses compact structure that harmonic drive and planet transmission combined together, small.

Description

A two-stage harmonic planetary gear reducer

【Technical field】

The utility model relates to the field of reducers, in particular to a two-stage harmonic planetary gear reducer.

【Background technique】

The reducer is an independent closed transmission device between the prime mover and the working machine. Used to reduce speed and increase torque to meet work needs. At present, the main types of domestic reducers are cylindrical gear reducer, bevel gear reducer, worm reducer, gear-worm reducer, planetary gear reducer and so on. Planetary reducers are widely used in various fields due to their large transmission ratio, high transmission efficiency, and compact structure. However, when the required transmission ratio is too large, the use of the planetary gear train structure alone leads to an excessively large volume of the reduction box, which limits its application range. Moreover, the planetary transmission has complex structure, many parts, large volume and high production cost.

【Content of invention】

The purpose of the utility model is to overcome the problems existing in the prior art, and provide a two-stage harmonic planetary gear reducer, which can reduce the volume while retaining a large transmission ratio.

In order to achieve the above object, the utility model adopts the following technical solutions:

It includes a wave generator set in the reducer housing to receive power. The wave generator is sequentially connected with a flexible spline and a rigid spline from the inside to the outside to form a first-stage harmonic gear transmission mechanism; the flexspline is coaxially connected with the sun gear. The front end of the reducer housing is provided with a motor interface, and the rigid wheel is fixedly installed on the inner wall of the motor interface;

The inner wall of the reducer housing is also integrally provided with an internal gear surrounding the outside of the sun gear, and a planetary gear set is arranged between the sun gear and the internal gear, and each planetary gear in the planetary gear set is connected to the planetary carrier for power output , forming a second-stage planetary gear transmission mechanism.

Further, the wave generator adopts a rolling friction wave generator.

Further, the flexible spline adopts a cup-shaped flexible spline.

Further, the flexible spline has 200 teeth, and the rigid spline has 202 teeth.

Further, the second-stage planetary gear transmission adopts the 2K-H(A) type.

Further, the sun gear, the internal gear and the planetary gear set all adopt spur gears.

Further, the number of teeth of the sun gear is 12, the number of teeth of the planetary gears in the planetary gear set is 30, and the number of teeth of the internal gear is 72.

Compared with the prior art, the utility model has the following beneficial technical effects:

The utility model adopts the first-stage harmonic gear transmission mechanism and the second-stage planetary gear transmission mechanism connected in series. The first-stage harmonic gear transmission mechanism is fixed by a rigid wheel, the wave generator is input, and the flexible wheel is output. Increase the transmission ratio of the reducer. The output of the first-stage harmonic gear transmission mechanism is used as the input of the second-stage planetary gear transmission mechanism, and finally output through the planetary carrier of the second-stage planetary gear transmission mechanism. This combination of harmonic transmission and planetary transmission has a structure Compact, small in size, light in weight, large in carrying capacity, high in transmission precision, small in backlash, stable in operation, etc.; at the same time, the internal gear and the reducer housing in the utility model are integrated, and on the premise of maintaining a large transmission ratio The volume of the whole reducer is reduced.

Furthermore, the utility model adopts a rolling friction wave generator to obtain rolling friction in the transmission, with small friction coefficient and high efficiency.

Furthermore, the utility model adopts the 2K-H(A) type, and the planetary transmission of this type has the characteristics of compact structure, small volume, light weight, convenient manufacture, and high transmission efficiency.

Furthermore, the utility model adopts the second-stage planetary gear transmission mechanism with a specific number of teeth, and the planetary transmission satisfies the conditions of fixed transmission ratio, assembly condition, concentric condition and adjacent condition, and the transmission ratio can reach 700.

【Description of drawings】

Fig. 1 is a sectional view of the utility model.

Fig. 2 is a structural diagram of the utility model.

Fig. 3 is a schematic diagram of the external structure of the utility model.

Fig. 4 is a sectional view of the planetary gear transmission of the present invention.

Among them: 1-wave generator; 2-flexible wheel; 3-rigid wheel; 4-sun gear; 5-planetary gear set; 6-planet carrier; 7-internal gear; 8-motor interface; 9-reducer housing .

【detailed description】

Below in conjunction with accompanying drawing, the utility model is described in further detail.

As shown in Figures 1 to 4, the utility model includes a wave generator 1 arranged in the reducer housing 9, and the wave generator 1 is sequentially sleeved with a flexible wheel 2 and a rigid wheel 3 from the inside to the outside to form a first-order harmonic The wave gear transmission mechanism; also includes a second-stage planetary gear transmission mechanism composed of the sun gear 4, the planetary gear set 5, the planet carrier 6 and the internal gear 7. The flexible gear 2 is coaxially connected with the sun gear 4.

The wave generator 1 is connected to the output shaft of the motor and used as the input end A of the reducer to receive power; the flexible wheel 2 adopts a cup-shaped flexible wheel; the front end of the reducer housing 9 is provided with a motor interface 8, and the rigid wheel 3 is fixed on the motor On the inner wall of the interface 8, the wave generator 1 is active, the rigid wheel 3 is fixed, and the flexible wheel 2 is output. The output end of the flexible spline 2 is connected with the sun gear 4 of the second-stage planetary gear transmission mechanism, and serves as the input end of the second-stage planetary gear transmission mechanism. The inner gear 7 is integrally arranged on the inner wall of the reducer housing 9 and is fixed, and the inner gear 7 surrounds the outside of the sun gear 4, the planetary gear set 5 is arranged between the sun gear 4 and the inner gear 7, and the planet carrier 6 is connected to the planetary gear. Each planetary wheel in the wheel set 5 is input by the sun gear 4, the planetary wheel set 5 rotates around the central axis and its own axis, and the planetary carrier 6 is output and used as the output terminal B of the overall reducer for outputting power.

The second-stage planetary gear transmission mechanism adopts the 2K-H(A) type. This type of planetary transmission has the characteristics of compact structure, small size, light weight, convenient manufacture, and high transmission efficiency. The sun gear 4, the internal gear 7 and the planetary gear set 5 all adopt spur gears.

The main working process and principle of the utility model: during use, the power is introduced from one end of the wave generator 1, the rigid wheel 3 is fixed, and is output by the flexible wheel 2, and the rotation direction of the flexible wheel 2 is consistent with the rotation of the wave generator 1 in the opposite direction. The output speed of the first-stage harmonic gear transmission mechanism is used as the input of the second-stage planetary gear transmission mechanism. The sun gear 4 is coaxial with the flex spline 2, the internal gear 7 is fixed, and the planetary gear set 5 is located between the sun gear 4 and the internal gear 7. Driven, the rotation of the planetary carrier 6 connected with the planetary gear set 5 is realized, and the coaxial output of power is finally completed.

When the rigid wheel 3 and the internal gear 7 are fixed, the wave generator 1 is input, and the planet carrier 6 is output, the utility model is a two-stage harmonic planetary gear reducer in which a single-stage harmonic gear mechanism is connected in series with a first-stage planetary gear mechanism. transmission structure, the transmission ratio relationship can be obtained as

i=i ₁ ×i ₂ (1)

The formula for calculating the transmission ratio i ₁ of the first-stage harmonic gear transmission mechanism is:

${\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}}}{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; G</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}}}{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

In the formula (2), Z _R is the tooth number of the flexible spline 2; Z _G is the tooth number of the rigid spline 3; n is the wave number.

The formula for calculating the transmission ratio i ₂ of the second-stage planetary gear transmission mechanism is

${\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; p</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}}}{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

In formula (3), p is the characteristic parameter of the planetary gear mechanism; Z _b is the number of teeth of the internal gear 7; Z _a is the number of teeth of the sun gear 4.

In summary, the formula for calculating the transmission ratio of the reducer of the present utility model is

$\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; R</span>}}}{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}}}{{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}}<span\; class="notranslate">\; )</span>$

The negative sign "-" in the formula indicates that the rotation of the planet carrier 6 as the output part is opposite to that of the wave generator 1 as the input part, that is, the rotation of the angular velocity w6 of the planet carrier ₆ and the angular velocity w1 of the wave generator ₁ on the contrary.

The specific embodiment of the utility model is as follows: in the first-stage harmonic transmission, the number of teeth of the rigid wheel 3 is 202, the number of teeth of the flexible wheel 2 is 200, and the wave generator 1 adopts a rolling friction wave generator among positive control wave generators. It is characterized in that the outer surface of the oval wheel is fitted with thin-walled rolling bearings to obtain rolling friction in the transmission, with small friction coefficient and high efficiency. Wave generator 1 is input, rigid wheel 3 is fixed, and flexible wheel 2 is output. For planetary gear transmission, the sun gear 4, the planetary gears in the planetary gear set 5 and the internal gear 7 all adopt spur gear planetary transmission. When the pressure angle is 20°, the minimum number of teeth without undercutting is 17. In the second-stage planetary gear transmission, the number of teeth of the sun gear 4 is set to 12, the number of teeth of the planetary gears in the planetary gear set 5 is 30, and the number of teeth of the internal gear 7 is 72. Since the number of teeth of the sun gear is less than 17, it is necessary to displace the sun gear 4 and the planetary gear and the internal gear 7 in the planetary gear set 5. Here, the height displacement is used. After calculation, the displacement coefficient of the sun gear 4 is selected as 0.31 , the coefficients of variation of the planetary gear and the internal gear 7 are both -0.31. The planetary transmission satisfies the condition of fixed transmission ratio, assembly condition, concentric condition and adjacency condition. According to the transmission ratio calculation formula, the transmission ratio i=700 is obtained.

If the modulus of all the gears of the planetary drive in the utility model is 1, then in the speed reducer, the maximum indexing circle diameter is 72mm. Most of the planetary reducers with a transmission ratio of 700 on the market are combined with multi-stage planetary transmission or use an internal gear with a large number of teeth and a sun gear with a small number of teeth to increase the transmission ratio of the planetary reducer. For example, an existing planetary reducer with a transmission ratio of 700 adopts three sets of planetary gears connected in series. The number of wheels is 6 and the number of teeth is 120. The transmission ratio of the second-stage planetary gear transmission is also 10, the number of teeth of the sun gear is 30, the number of teeth of the internal gear is 270, the number of planetary gears is 6, and the number of teeth is 120. The transmission ratio of the third-stage planetary gear transmission is 7, the number of teeth of the sun gear is 20, the number of teeth of the internal gear is 120, the number of planetary gears is 4, and the number of teeth is 50. All planetary gear transmissions satisfy the conditions of constant transmission ratio, concentricity, assembly and adjacency. If the modulus of all gears is 1mm, then the maximum pitch circle diameter of the gears of the planetary reducer is 270mm, which is far larger than the utility model.

Therefore, compared with the planetary gear reducer with a transmission ratio of 700 on the market, the volume of the reducer of the utility model is greatly reduced.

The utility model adopts the combination of harmonic transmission and planetary transmission. Since the two-stage harmonic planetary gear reducer adopts harmonic gear transmission with multiple teeth meshing, it has the characteristics of large transmission ratio and small volume. The gear transmission adopts the 2K-H(A) type or NGW transmission form. This type of planetary transmission has the characteristics of small size and compact structure, so it has the characteristics of compact structure, small size, light weight, large bearing capacity, It has the characteristics of high transmission precision, small backlash and stable operation. Especially under the premise of ensuring the small size of the device, the transmission ratio of the reducer is greatly improved.

Claims (7)

1. a two-stage harmonic planetary gear reduction unit, it is characterised in that: it is used for receiving in including being arranged on reducer shell (9) The wave producer (1) of power, wave producer (1) is socketed flexbile gear (2) the most successively and has just taken turns (3), forming the first order Harmonic gear drive mechanism；Flexbile gear (2) coaxially connected sun gear (4), reducer shell (9) front end arranges motor interface (8), Just wheel (3) is fixedly mounted on motor interface (8) inwall；

Also it is wholely set on reducer shell (9) inwall and is looped around the internal gear (7) that sun gear (4) is outside, sun gear (4) And between internal gear (7), it being provided with planetary gear set (5), each planetary gear in planetary gear set (5) is all connected with for exporting power Planet carrier (6), form second level planetary gear mechanism.

A kind of two-stage harmonic planetary gear reduction unit the most according to claim 1, it is characterised in that: wave producer (1) is adopted Use rolling friction type wave producer.

A kind of two-stage harmonic planetary gear reduction unit the most according to claim 1, it is characterised in that: flexbile gear (2) uses cup Shape flexbile gear.

A kind of two-stage harmonic planetary gear reduction unit the most according to claim 1, it is characterised in that: flexbile gear (2) number of teeth is 200, just wheel (3) number of teeth is 202.

A kind of two-stage harmonic planetary gear reduction unit the most according to claim 1, it is characterised in that: second level planetary gear Drive mechanism uses 2K H (A) pattern.

A kind of two-stage harmonic planetary gear reduction unit the most according to claim 1, it is characterised in that: sun gear (4), interior Gear (7) and planetary gear set (5) all use straight spur gear.

A kind of two-stage harmonic planetary gear reduction unit the most according to claim 1, it is characterised in that: the tooth of sun gear (4) Number is 12, and the planetary gear number of teeth in planetary gear set (5) is 30, and the number of teeth of internal gear (7) is 72.