RU2757326C1 - Planetary rattle running clutch - Google Patents

Abstract

FIELD: mechanical engineering.SUBSTANCE: invention relates to mechanical engineering. The planetary ratchet overrunning clutch contains a gear planetary gear, in which the central wheel is the driving half of the coupling, and the carrier is the driven half of the clutch with satellites coupled to the central wheel. The satellites are mounted with end ratchet wheels fixed in the tangential and axial directions, and on the carrier coaxially with the disks, ratchet wheels fixed in the tangential direction and spring-loaded to the disks are mounted with the possibility of engagement with the end ratchets.EFFECT: improved performance is provided.1 cl, 10 dwg

Description

The proposed invention relates to mechanical engineering and is intended for connecting shafts that transmit large moments in one direction at a high switching frequency, for example, in non-friction high-torque variators.

Known friction overrunning clutches, in which the moment is transmitted by friction forces between the leading and driven half couplings through the body wedged [1, p. 800]. In such couplings, the contact loads between the parts of the friction pairs exceed the useful tangential forces by more than 10 times, which is an obstacle to the use of such types of couplings at a high frequency of engagement and transmission of large torques. Also known are ratchet overrunning clutches, the design of which uses a gear connection between the driving and driven half couplings [1, p. 806], which ensures the transmission of large moments, but such clutches have a sufficiently large (15 ... 20 °) response angle, which is unacceptable, for example , in non-friction high-torque variators [2].

Let us take for the prototype the closest in technical essence and the achieved result a gear overrunning clutch with practically zero angle of operation [3]. It contains a gear planetary gear, in which the central wheel is the leading half of the coupling, and the carrier is the driven half of the coupling with satellites coupled to the central wheel, disks fixed in the tangential direction are mounted on the satellites, and stops contacting the disks are made on the carrier, while the satellites are spring-loaded to stops.

The features of the known clutch (prototype), which coincide with the inventive gear overrunning clutch, are as follows. It contains a gear planetary transmission, in which the central wheel is the driving half of the coupling, and the carrier is the driven half of the coupling with satellites coupled to the central wheel, and the disks fixed in the tangential direction are mounted on the satellites.

In the known clutch, the fixation of the half-couplings from relative rotation during the transmission of rotation (working stroke) is carried out by friction forces between the discs and stops, which limits the transmitted torque, and the complexity of the structure also occurs.

The purpose of the present invention is to increase the efficiency by reducing the clutch actuation angle by an order of magnitude in comparison with existing ratchet overrunning clutches.

The proposed toothed freewheel clutch has the following essential features. It contains a gear planetary gear, in which the central wheel is the driving half of the coupling, and the carrier is the driven half of the coupling with satellites coupled to the central wheel, while the satellites are mounted with end ratchet rings fixed in the tangential and axial directions, and on the carrier coaxially to the disks are installed with the possibility of engagement with end ratchets, ratchet wheels fixed in the tangential direction and spring-loaded to the discs

Distinctive features of the prototype of the invention are as follows. In the proposed planetary ratchet overrunning clutch, the disks are made with end ratchets and are fixed in the axial direction, and on the carrier, coaxially with the disks, ratchet wheels fixed in the tangential direction and spring-loaded to the disks are mounted with the possibility of engagement with the end ratchets

FIG. 1 ... 6 shows a variant of the design of a planetary ratchet overrunning clutch, in Fig. 7 ... 8 show the loads during transmission of rotation, and FIG. 9 ... 10 - angular speeds of the clutch links during overtaking.

The proposed clutch (Fig. 1) contains a gear planetary gear, in which the central wheel 1 is the leading one, and the carrier 2 is driven by the half-couplings. _{The carrier consists of two halves 2 1} and 2 ₂ connected by three pins 3 and nuts 4 with trunnions 5 and 6. A gear rim 7 is made on the central wheel, and a cylindrical support 8 of the central _{wheel is made on the carrier 2 1.} On the carrier 2 ₂ , spline necks 9 are fixed coaxially to the studs. Three satellites 10a, 10b, and 10c (Fig. 2) are mounted on the studs with the possibility of rotation, coupled to the central wheel, on which disks 11 with an end ratchet ring 12 are fixed in the tangential and axial directions. Ratchet wheels 13, spring-loaded in the direction of the satellites by springs 14. Between the satellites, a parasite 15 coupled to them is mounted on the splined journals 9 movably in the axial direction. FIG. 3 and 4 show the clutch when transmitting rotation (working stroke) clockwise when viewed from the side of the pivot 6. In the clutch, fixing the coupling halves during the transfer of rotation is provided by connecting the ratchet wheel 13 with the end ratchet ring 12 of the disk 11 of the satellite 10a, while the other ratchet wheels are shifted with respect to the ratchet rings of the satellites 10b and 10c, respectively, at S / 3 and 2S / 3, where S is the pitch of the teeth of the ratchet rings and ratchet wheels at a radius R _x (Figs. 5 and 6).

The proposed clutch works as follows. When transmitting rotation (Figs. 3 and 4), both half-couplings rotate at a speed ω in the direction of the external moment M on the driving half-coupling (central wheel 1), overcoming the moment of resistance M on the driven half-coupling (carrier 2). In this case, the satellite 10a is fixed from rotation relative to the carrier by a ratchet wheel 13, m is the moment on the satellite. FIG. 7 and 8 show the nature of the loads in the clutch during transmission of rotation with the parasite 15 and without it, Fig. 9 and 10 - when overtaking, where R and r are the centroids of the gears and satellites. Gear ratio of planetary gear

where z _K and z _C are the number of teeth in the central wheel and satellites.

Transmitted torque when transmitting rotation with a parasite (Fig. 7)

M = F × R + 2 × 0.5F × R = 2FR,

и момент на сателлитеwhere

and a moment on the satellite

The moment on the satellite without a parasite (fig. 8)

The clutch is functional even without a parasite, but it allows to halve the contact load in the satellite-central gear pair.

When overtaking, the moment is not transmitted (Figs. 9 and 10), and when the carrier stops, the speeds of the satellites are ω ₁₀ = ωU, where ω is the speed of the central wheel.

The angle of rotation of the satellite relative to the ratchet wheel 13 at which the end gear rim 12 engages with the ratchet wheel is equal to

where z _X is the number of teeth of the ring gear and ratchet wheel. The maximum angle of the clutch actuation, that is, the relative rotation of the half-couplings when they are fixed, and taking into account the phase shift by β / 3 and 2β / 3 of the ratchet wheels relative to the satellites (Figs. 5 and 6), will be

For z _C = 10, z _K = 40 and z _X = 28 we have

Consequently, the angle of operation α = 0 ° ... α _max = 0 ° ... 1.07 °, which is an order of magnitude less than that of existing ratchet overrunning clutches, and makes it possible to use the proposed clutch in non-friction high-torque variators.

The leading half of the coupling can be either a carrier or a gear wheel, and the number of satellites is limited by their design dimensions.

Sources of information:

1. A.F. Krainev. Mechanics of machines. Fundamental Dictionary - 2nd ed. M. Mechanical engineering. - 2001 (pp. 800, 806).

2. RF patent No. 2242654 C2, F16H 29/08. High torque variator. / Author: B.V. Pylaev. - Prior .: 20.01.2003.

3. RF patent No. 2353835 C2, F16D 41/08. Toothed overrunning clutch. / Authors: B.V. Pylaev and A.A. Shamin. - Prior .: 27.03.2007.

Claims (1)

A planetary ratchet overrunning clutch containing a gear planetary gear, in which the central wheel is the driving half of the clutch, and the carrier is the driven half of the clutch with satellites engaged with the central wheel, and the satellites are mounted on tangentially fixed discs, characterized in that the discs are made with end ratchet crowns and are fixed in the axial direction, and on the carrier coaxially with the disks are mounted with the possibility of engagement with the end ratchets, the ratchet wheels fixed in the tangential direction and spring-loaded to the disks.

Images