RU2292501C1 - Reduction gear - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: reduction gear comprises housing (1), output shaft (6) with eccentric (5), two-rim satellite (4) mounted on the eccentric, and unmovable (11) and movable (3) central wheels. The number of teeth in two gear rims of satellite (4) is the same, and the hollows between the teeth are cylindrical but have different dividing diameters and distances between the center of the circumferences that define the form of the hollows between the teeth.

EFFECT: reduced sizes and simplified structure.

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Description

The invention relates to mechanical engineering, namely to gearboxes with intermediate bodies in gearing and allows to obtain large gear ratios (maximum gear ratio is not limited) with small overall dimensions, and the number of manufactured parts for gearboxes with different gear ratios remains unchanged.

Most effectively, the present invention can be applied in gear motors, wheel gears, winches.

Known gearbox with pins rotating in cylindrical holes (US patent No. 5,509,861 IPC F 16 H 1/32 NKI 475/162), where the satellite makes a planetary motion due to the eccentric. A satellite, in the cylindrical openings of which the pins freely rotate, rolling around the stationary wheel of the housing, transmits the rotation to the output shaft.

The disadvantages of this device are the large size of the gearbox and the console installation of the pins, which leads to rapid wear of the gearbox.

The closest technical solution, selected as a prototype, is a gearbox with cycloidal gearing (RF patent No. 2123627, IPC F 16 H 1/32), the teeth of the two central wheels of which are made in the form of hand sprockets located around the circumference. The satellite is made in the form of a block of gears with a different number of teeth, the surface of each of which is formed by a guide, which is a closed epicyclic line. The satellite rotates on an eccentric rigidly mounted on the drive shaft.

The disadvantages of the gearbox are the complexity of the design (pin with bearings), large dimensions and the difficulty of obtaining a closed epicyclic line for the gears of the satellite.

The technical result of the invention is to reduce the dimensions, obtain large gear ratios and simplify the design.

The technical result is achieved by the use of standard rollers (instead of the spindles with bearings) and a change in design.

The essence of the invention lies in the fact that in a gearbox with intermediate bodies in gearing, the possibility of manufacturing a gear wheel with any pitch diameter independent of the gearing module (as with involute gearing) is used, which allows you to design a gearbox with any gear ratio.

The proposed gearbox differs from the prototype:

- the method of attachment and the design of the intermediate gearing bodies;

- a profile of gear teeth;

- the number of teeth on the crowns of the satellite, in contrast to the prototype, is the same.

The attached figure 1 and figure 2 presents the gearbox, which shows the following notation:

1 - housing to which the gearbox is attached;

2 - a gear rim of a movable central wheel;

3 - movable central wheel;

4 - satellite;

5 - eccentric;

6 - drive shaft;

7 - bearing;

8 - rollers;

9 - bearings;

10 - ring;

11 - fixed central wheel;

d ₁ and d ₂ - dividing diameters of the gears of the satellite;

r is the radius of the cavity between the teeth;

α ₁ and α ₂ - the distance between the centers of circles, forming a depression between the teeth of the satellite.

The gearbox with the intermediate gearing gears (Fig. 1) consists of two central gears with internal gearing: one fixed wheel 11 is fixed to the body of the main mechanism or engine 1, the second gear 3 rotates during operation of the gearbox and is its output link. To transfer rotation from the gearbox to the next links, the wheel 3 has a ring gear 2. Instead of a ring gear 2, a lever, a disk of a wheel, a winch drum, etc. can be fixed on the wheel 3. An eccentric 5 is fixedly mounted on the drive shaft 6, rotating in the bearings 9. The satellite 4 is made in the form of a block of gears with the same number of teeth and performs planetary motion on the eccentric 5. The gearing between the satellite 4 and the central gears 3 and 11 is carried out through needle rollers 8, mounted in the nests of the central gears 11 and 3 with a small gap allowing them to rotate freely, but not to fall out of the nests. The number of teeth of the central wheels 11 and 3 is greater than the number of teeth of the satellite 4. The ring 10 acts as a sliding bearing between the central gears 11 and 3 and at the same time limits the free movement of the needle rollers 8 in the axial direction. The entire gearbox is assembled with a single nut.

Figure 2 shows a side view of the satellite 4, allowing to show the profile of the teeth of the gears of the satellite. Both satellite crowns have the same number of teeth and the radius r of the depression between the teeth, but differ in dividing diameters d ₁ and d ₂ and the distance between the centers of the circles forming the surface of the depressions α ₁ and α ₂ . The smaller the difference in pitch diameters α ₁ and α ₂ , the greater the gear ratio of the gearbox.

The gearbox operates as follows.

Under the action of the eccentric 5, rotating together with the drive shaft 6, the satellite 4 rolls around the stationary central wheel 11. For one revolution of the input shaft 6, the satellite 4 rotates by the difference between the numbers of teeth of the satellite 4 and the central wheel 11. The radius profile of the cavity between the teeth allows one to produce tool gears with any number of teeth. The gear rims of the satellite 4, having different peripheral speeds (due to the difference in pitch diameters d ₁ and d ₂ ), transmit the rotation to the movable central wheel 3. The gear ratio of the gearbox is not related to the number of teeth, therefore it can be expressed by any number.

U is the gear ratio of the gearbox;

D ₁ , D ₂ - dividing diameters of the central wheels;

d ₁ , d ₂ - dividing diameters of the gear rims of the satellites.

Claims (1)

The gearbox with the intermediate bodies in gearing rotates the input shaft to the eccentric, the twin-shaft stellite mounted on the eccentric, rolls around the stationary central wheel, transfers the rotation to the movable central wheel due to the difference in the pitch diameters of the gears of the satellite, characterized in that the two gears of the satellite have the same number of teeth and cylindrical profiles of the hollows between the teeth, but differ in pitch diameters and the distances between the centers of the circles forming the profile cavities between the teeth.

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