SK50692009U1 - Planetary speed reducer - Google Patents

Description

Technical field

The invention relates to a planetary speed reducer, in which at least two satellites, supported on a carrier coupled to the driven (output) shaft, orbit between the central sun gear and the fixed ring gear with internal toothing.

BACKGROUND OF THE INVENTION

A planetary speed reducer is known which consists of a drive central gear (coupled to a drive or input shaft) and a fixed ring gear (rim) with internal gear. Between the central and crown wheel there is an annular ring whose width is equal to the diameter of the satellites rolling simultaneously along the central wheel and the crown wheel. These are driven satellites, which are generally connected by a carrier to which the driven (output) reducer shaft is connected. This known reducer is a proven design for speed reduction, with a linear course of torque / speed ratio, i. torque increases as many times as speed decreases.

From published CZ application PV 609-93 "A planetary gearbox is a known reversible planetary speed reducer in which the above-described classical planetary gearbox is mounted substantially twice in a row, i.e. with two central wheels on the drive shaft and with a double ring forming a ring gear, which in this case is rotatably supported, the first two satellites being connected to the housing, and the second two satellites are then connected to the output shaft via a carrier. The purpose of the solution is to reduce the installation dimensions of gearboxes in large gearboxes, but the torque does not increase compared to a conventional gearbox.

U.S. Pat. No. 4,856,376 discloses a bicycle transmission comprising a central gearwheel (coupled to a pedal shaft), further interposed by means of a small and large gearwheel on a common axis, which are non-satellite, i.e. they do not circulate around the sun gear, but their axes are connected to the housing, and finally from a ring gear with an internal toothing that engages the intermediate gear and the external toothing on which the bicycle chain is mounted. The solution described is applicable to bicycles but is not suitable for transmitting greater forces and torques.

The object of the invention is to provide a planetary speed reducer whose transmission would be characterized by a higher torque and which would be structurally versatile for a wide range of applications. It is also desirable that the inlet and outlet shafts of the reducer have the same sense of rotation, and that the reducer has the possibility of reversing operation, i. to work both right-handed and left-handed.

The essence of the technical solution

This problem is solved by providing a planetary speed reducer in which two co-operating transmission satellites are arranged rotatably mounted on the carrier pins, one engaging the central gear and the other with the driven satellite, between the central gear and each driven satellite, gear, operating satellites and powered satellites have the same diameters and their centers lie in a single line.

The embedded transmission satellites maintain the same sense of rotation of the driven shaft and the drive shaft. The driven satellite acts on the longer arm and increases the output torque.

In one preferred embodiment of the invention, the powered satellite is rotatably mounted on the carrier pin as well as the operating satellites, and the carrier is coupled to the driven shaft, as is the case with known planetary speed reducers. In this embodiment, the reducer according to the invention has a gear ratio given by the carrier diameter.

In another preferred embodiment of the invention, the driven satellite is coupled to and driven by a connecting shaft rotatably mounted in the carrier and passing therethrough to a pinion engaging a driven wheel coupled to the driven shaft. In this embodiment, the reducer can be equipped with an additional gear whose transmission ratio depends on the diameter of the driven satellite, the pinion diameter, and the diameter of the driven wheel.

As far as the satellite carrier is concerned, in the first preferred embodiment, the carrier has two to five symmetrically arranged arms, each of which is associated with two operating satellites and one powered satellite.

In another preferred embodiment, which is more suitable for a plurality of satellites and thus for transmitting higher torques, the carrier preferably has a circular shape.

The advantages of a planetary speed reducer according to the invention are, in particular, that, at the same ratio of input and output speeds, it allows transmission of higher torque than the reducers used up to now. The reducer can work both right-handed and left-handed, while maintaining the same sense of rotation of the drive and driven shafts. Increasing the output torque enables the sizing of the gears to achieve a reduction in the required power consumption of the drive motor or a reduction in fuel consumption. The planetary speed reducer according to this technical solution can be used universally for driving any means of transport, power equipment, cableways, winches and the like. The most suitable field of application is aviation, where it can be used as a reducer for turboprop engines and for driving helicopter rotors. A special field of application is represented by the electric drives of wheelchairs, where the use of the described speed reducer significantly increases the range of wheelchairs on a single charge.

BRIEF DESCRIPTION OF THE DRAWINGS

The technical solution will be explained in more detail by means of the drawings in which FIG. 1 is a sectional view of a planetary speed reducer with a two-arm carrier coupled to a driven shaft; FIG. 2 shows an axial view of the inner part of the reducer according to FIG. 1 from the driven shaft side, FIG. 3 is a cross-sectional view of a planetary speed reducer with a circular carrier and a driven shaft provided with a driven wheel driven by pinions coupled to the driven satellites.

Examples of technical solution

It is to be understood that the specific embodiments of the invention described and illustrated below are presented by way of illustration, not by way of limitation, of the embodiments of the invention for the aforementioned cases. Those skilled in the art will find, or will be able to detect, using routine experimentation, more or less equivalents to the specific embodiments of the invention specifically described herein. These equivalents will also be included within the scope of the following protection claims.

In one embodiment shown in FIG. 1 and FIG. 2, the planetary speed reducer is driven by a drive shaft 7 mounted in a bearing 9 on which the spur gear 1 is mounted. On the other hand, a driven shaft 8, supported in a bearing 10, on which the two-arm carrier 4 is rotated together with the driven shaft 8, protrudes from the reducer. In the center of the carrier 4 is a pivotally mounted pin of the sun gear 7, the wheel 7 can rotate independently and at different speeds. The bearing can be sliding or rolling. On each of the arms 15 of the carrier 4, two transmission satellites 3 and one driven spur gear 2 with spur gear 6 are rotatably mounted on pins 5, which roll along the internal toothing of the fixed ring gear 6. The diameters d of the drive sun gear 1, dj of the operating satellites 3, d _{2 of the} powered satellite are identical, ie. d = di = d ₂ (or the diameters of the pitch circle of their teeth). In the same direction of rotation, the drive shaft 7, the sun gear 1, the second operating satellite 3, and the drive shaft 4 with the driven shaft 8 rotate. The number of arms 15 of the carrier 4 depends on the magnitude of torque transmitted, and generally ranges from two to five.

The applied input torque Tm _input on the drive sun gear 1 exerts a force F = Tm _vs tup: 0.5 d. Through the transmission satellites 3, the force F is transmitted to the driven satellite 2, whose toothing coincides with the other of the operation satellites 3 and on the opposite side with the internal toothing of the fixed ring gear 6. The radial force Frad = 2F is applied to pin 5 of the driven satellite 2. in multiples of the arm R _{of the} gripper 4 gives the output torque Tm _{V s} s. The calculation of the output torque Tm _of the carriers characterized _in t 4 is performed according to the relationship:

_The YST dark. = Tm _vs t _U pi [kgm], where i = gear ratio.

. 2Rs Q, 5d

The output speed n _{in the} carrier 4 is determined as:

Out - n _In step (1 1) [rpm], and h n n _— out = —- [rpm].

^y D + d

In a planetary speed reducer according to the technical solution in this embodiment, the output torque Tm st st. compared to the Tm _vs t _up increases 12x, while the output speed n _{wherein S} t. will be reduced by 8x compared to n _input . The ratio 12: 8 = 1.5: 1 is higher than that of a conventional planetary reducer, where the ratio is 1: 1.

In the second embodiment, for transmitting lower torques, as shown in FIG. 3, the arrangement of the planetary speed reducer is similar, except that the driven shaft 8 is not connected to the carrier 4, but to the driven wheel 13, which drives the pinion 12 connected by a connecting shaft 14 which freely rotates through the carrier 4 to the driven pinion 2 Here, the carrier 4 has its own bearing 11 for rotatably supported, and is formed by a disk on which a pinion 12 base is arranged symmetrically, each of which is connected to a respective driven satellite 2 driven by respective operating satellites 3 from the driving sun gear 1. operating satellites 3 is the same as in the first embodiment. By selecting the diameters of the pinion 12, the driven satellites 2 and the driven wheel 13, the magnitude of the forces on the pinion 12 (diameter d ₃ ) and the radius of the driven wheel 13 (diameter D 1) is influenced. If the diameter D ₂ of the driven satellite 2 d ₃ of the pinion 12 equal, the radial force F _£ the pinion 12 equal to the force F to the first sun gear output torque T m _{in the Y (.} The output shaft 8 is determined as the Tm _V ý _S t, = F _r · 0,5 Di where Di is the diameter of the driven wheel 13.

If the diameter d _{3 of the} pinion 12 is greater than the diameter d _{2 of the} driven satellite 2, then the force F _r shall be determined by the relation:

F _r = (F · d ₂ ): (0.5 d ₃ + 0.5 d ₂ )

The output speed n _{y of the} driven shaft 8 is determined according to the relation:

Whistle ⁼ nape

2RS + H ₃ 7 -x [rpm] with n up to _a speed of the carrier 4 and the expression x = (--1) indicates the rotational speed of the driven _d2 satellite 2 (and also the rotational speed of the pinion J 2) in one revolution ( ie 360 °) of the carrier 4 and the eight turns of the sun gear J.

In this embodiment, the planetary speed reducer can be provided with additional gears, including overdrive, by selecting the diameter d _{3 of the} pinion 12 and the diameter of the driven wheel 13.

Some examples of additional transfers are listed below:

Example 1:

Di: 0 d ₃ = 5: 1 T m Out ⁼ T ITlInput '5 Flst ⁼ Rivstup · 3,333

Ί

Example 2:

0Df 0 03 = 3: 1 Trriyst ⁼ Tm _vs tup '3.6 n _out - n _In degree2.4

Example 3:

Dú 0 d ₃ = 2: 1 Trigger ⁼ Tm _In degree 2.6 rival ⁼ riser 1.777

Example 4:

Dú 0 d ₃ = 1: 1 T m out ⁼ T m _vs tup '1,5 rivst - rivstup

Example 5:

Dy 0 d ₃ - 1: 2 Traction ⁼ Tmput '0,8 rival - rivstup' 1,875

Industrial usability

The planetary speed reducer according to the invention can be used in transport, especially in aviation, e.g. as a reducer for turboprop engines and for helicopter rotor drives, and versatile in industry wherever higher torque needs to be achieved while reducing drive speed.

Claims (5)

PROTECTION REQUIREMENTS A planetary speed reducer, comprising a driving central gear (1), a fixed ring gear (6) with internal gear and at least one driven satellite (2) rolling along the internal gear of the fixed ring gear (6), and connected via a carrier (4) ) with a driven shaft (8), characterized in that between the sun gear (1) and the driven satellite (2) are arranged two co-operating operating satellites (3) rotatably mounted on pins (5) of the carrier (4); one of which meshes with the sun gear (1) and the other with the driven satellite (2), wherein the pitch circles of the sun gear (1), the operating satellites (3) and the driven satellite (2) have the same diameters, and their centers lie in one line. The planetary speed reducer according to claim 1, characterized in that the driven satellite (2) is rotatably mounted on a pin (5) of the carrier (4), and the carrier (4) is connected to the driven shaft (8). The planetary speed reducer according to claim 1, characterized in that the driven satellite (2) is connected to a pinion (12) engaging the driven wheel by means of a connecting shaft (14) which is rotatably mounted in and passes through the carrier (4). (13) coupled to the driven shaft (8). The planetary speed reducer according to at least one of claims 1 to 3, characterized in that the carrier (4) has two to five symmetrically arranged arms (15), each of which is associated with two operating satellites (3) and one driven satellite (2). The planetary speed reducer according to at least one of claims 1 to 3, characterized in that the carrier (4) is of circular shape.