WO2019090899A1

WO2019090899A1 - Modular precision cycloidal rotary joint speed reducer

Info

Publication number: WO2019090899A1
Application number: PCT/CN2017/116690
Authority: WO
Inventors: 周世才
Original assignee: 殷爱国
Priority date: 2017-11-07
Filing date: 2017-12-16
Publication date: 2019-05-16
Also published as: CN107747612A

Abstract

A modular precision cycloidal rotary joint speed reducer, comprising a pin wheel housing (1), a planet carrier (2), crank shafts (3), a wheel pin (4), a cycloidal gear (5), a sun gear (6), and planet gears (7). The planet carrier (2) passes through and is supported in the pin wheel housing (1) by a roller bearing. n crank shafts (3) pass through the planet carrier (2) and have two eccentric portions offset by 180 degrees. The eccentric portion is coupled to the cycloidal gear (5) via a roller bearing. The cycloidal gear (5) engages in the pin wheel housing (1) via the wheel pin (4) accommodated in a wheel pin hole in an inner wall of the pin wheel housing (1). Each end of the crank shaft (3) is supported in the planet carrier (2) by a tapered roller bearing, and is fixedly coupled to the planet gear (7) via a spline and a retaining ring. The two or more crank shafts (3), the cycloidal gear (5), and the planet carrier (2) form a parallelogram-shaped mechanism. The sun gear (6) passes through and is supported on the planet carrier (2) and the cycloidal gear (5), and an upper tooth portion thereof engages with the planet gear (7). n planet gears (7) fixedly coupled to n crank shafts (3) are uniformly distributed around and engage with the sun gear (6). The number of teeth of the planet gear (7) and the number of teeth of the sun gear (6) is a multiple of n. A relative phase of an internal spline of the planet gear (7) is consistent with that of upper teeth thereof.

Description

Modular precision cycloidal rotary joint reducer

Technical field

The invention provides a modular precision cycloidal speed reducer, which is used for a robot rotary joint, a machine tool turntable and the like which require high rotation precision.

Background technique

BXJ reducer is a new type of transmission developed on the basis of cycloidal pin wheel. It has a series of large rigidity, large transmission ratio range, large bearing capacity, high motion precision, high transmission efficiency, small backlash and small volume. advantage.

The BXJ reducer consists of two parts: an involute cylindrical planetary reduction mechanism and a cycloidal needle mechanism. The input of the cycloidal stage is composed of at least two crankshafts, which constitute one or more parallelograms, and each planetary gear of the star line. They are respectively splined with their corresponding crankshafts, which puts an assembly requirement on the relative phase of the internal splines and external teeth of the planetary gears. In other words, in general, the inner splines and outer teeth of each planet wheel have different relative phases, and need to be accurately ensured, otherwise they cannot be assembled. This puts high requirements on the manufacture of the planetary gears, and thus reduces Production efficiency increases manufacturing costs.

Summary of the invention

The object of the present invention is to provide a modular precision cycloidal rotary joint reducer with reasonable structure, low cost and modularity.

The technical solution of the invention is a modular precision cycloidal rotary joint reducer, which comprises a pin gear shell, a planet carrier, a crank shaft, a pin gear pin, a cycloidal wheel, a sun gear and a planetary gear, and the planet carrier is supported by a rolling bearing. In the pin gear housing, n crank shafts are disposed in the planet carrier and have two eccentric portions displaced by 180°, and the eccentric portion is coupled to the cycloidal wheel through a roller bearing, and the cycloidal wheel is accommodated in the inner wall of the pin gear housing. The pin gear pin in the pin pin hole is engaged in the pin gear shell, and both ends of the crank shaft are supported in the planet carrier by the tapered roller bearing, and the planet gear is fixed by the spline and the retaining ring, and two or more crank shafts and cycloids The wheel and the planet carrier form a parallelogram mechanism, and the center gear is supported in the planet carrier and the cycloidal wheel and the upper tooth portion thereof meshes with the planetary wheel; wherein the center gear is uniformly meshed with n and is fixed at n The planetary gears on the crankshaft, the number of teeth of the planetary gear and the sun gear are multiples of n, and the inner splines of the planetary gears are in phase with the relative outer teeth.

The invention sets the number of teeth of the sun gear and the planetary gear to a multiple of the number of the planetary gears of each reducer, and has the advantages that the phase of the inner spline and the outer tooth of the planetary gear can be set to an arbitrary value, and only needs to be consistent. It can be convenient, reliable and save a lot of fixtures. Under the premise of ensuring sufficient transmission strength, the spline parameters of the planetary gears of various frame reducers can be the same, so only a small number of tools and fixtures can be used. It meets the production requirements of the entire series of reducers, saves a lot of manpower and material resources, and at the same time improves production efficiency, which greatly reduces the production cost of the entire series of reducers; all the components except the planetary wheels are shaped, and the center wheel is reserved. And the installation space of the planetary wheel, when different speed reduction ratios are required, only the corresponding center wheel and the planetary wheel can be installed, thereby realizing modular production, which is advantageous for mass production, saving product management cost and improving response. The speed of the market.

DRAWINGS

Figure 1 is a schematic structural view of the present invention;

Figure 2 is a schematic diagram of the transmission of the present invention;

Figure 3 is a schematic view showing the structure of the center gear and the planetary gear meshing transmission of the present invention.

In the figure: the pin housing 1, the carrier 2, the crank shaft 3, the pin gear 4, the cycloidal wheel 5, the sun gear 6, the planetary gear 7, and the pin gear hole 8.

Detailed ways

The invention will be further described below in conjunction with the drawings and embodiments.

A modular precision cycloidal rotary joint reducer shown in Figures 1, 2, and 3 includes a pin gear housing 1, a carrier 2, a crank shaft 3, a pin gear 4, a cycloidal wheel 5, a sun gear 6, and a planetary gear 7. The planet carrier is supported by the rolling bearing in the pin gear housing, and the n crank shafts are disposed in the planet carrier and have two eccentric portions offset by 180°, and the eccentric portion is coupled with the cycloidal wheel through the roller bearing, the cycloidal line The pin gear pin accommodated in the pin hole of the inner wall of the pin gear case is engaged in the pin gear case, and both ends of the crank shaft are supported in the planet carrier by the tapered roller bearing and the planet wheel is fixed by the spline and the retaining ring. Two or more crankshafts, a cycloidal wheel and a planet carrier form a parallelogram mechanism, and the central gear is supported by the carrier and the cycloidal wheel and the upper teeth thereof mesh with the planetary gear; wherein: the central gear is surrounded by The cloth meshes n planets that are fixed on the n crankshafts. The number of teeth of the planet gears and the sun gear is a multiple of n, and the inner splines of the planet gears coincide with the relative phases of the upper teeth.

Let the number of teeth of the center wheel be z ₁ and the number of teeth of the planet wheel be z ₂ , then at the position of the planet wheel b, the meshing point of the planet wheel b moves z ₁ /3 pitch between the meshing nodes of the planet wheel a, the center wheel The meshing node reverses the z ₂ /3 pitch. In this embodiment, the number of teeth of the three planetary wheels and one central wheel can be divisible by three, and the planetary gear can be smoothly loaded; if it cannot be divisible, it must be 1/3 or 2/3 pitch, obviously if the planetary gear The difference is 1/3 pitch, the center wheel is 2/3 pitch apart, or the planetary wheel is 2/3 pitch apart, the center wheel is 1/3 pitch apart, and the planet wheel can also mesh correctly with the center wheel. In summary, if the number of teeth of the center wheel and the planet wheel is a multiple of 3, the internal splines of the three planet wheels and the external teeth can be properly meshed.

Claims

A modular precision cycloidal rotary joint reducer comprises a pin gear shell, a planet carrier, a crank shaft, a pin gear pin, a cycloidal wheel, a sun gear and a planet gear, and the planet carrier is supported by the rolling bearing in the pin gear shell. The n crankshafts are disposed in the planet carrier and have two eccentric portions with a 180° misalignment. The eccentric portion is coupled to the cycloidal wheel through a roller bearing, and the cycloidal wheel is received in the pin hole of the inner wall of the pin gear housing. The pin gear is engaged in the pin gear shell, and both ends of the crank shaft are supported in the planet carrier by the tapered roller bearing and the planet gear is fixed by the spline and the retaining ring, and the two crankshafts and the cycloidal wheel are parallel with the planet carrier. a quadrilateral mechanism, the sun gear is supported in the planet carrier, the cycloidal wheel and the upper tooth portion meshes with the planet gear; wherein the central gear is uniformly meshed with n planets fixed on the n crankshafts The number of teeth of the wheel, the planet wheel and the sun gear is a multiple of n, and the internal splines of the planet gear coincide with the relative phase of the upper teeth.