RU195354U1 - Freewheel - Google Patents

Abstract

The utility model relates to the field of mechanical engineering and can be used in autonomous power supply systems for transmitting unidirectional torque using a magnetic field between two vertical coaxial shafts operating at low speeds, separated by a sealed partition both under pressure differential between the sealed cavities, and under normal conditions. The technical result of the utility model is to obtain the properties of a contactless unidirectional node, subject to simplicity design and technological design. The coupling consists of a leading and driven coupling half mounted coaxially. The leading coupling coupling contains a shaft 1 with an asterisk 2 mounted thereon on a press fit, on top and bottom of which a fixed 3 and movable 4 limiter rigidly connected to the sprocket are mounted, rotatable and mounted on the shaft 1 by means of a bearing 5. Between the stops, in the inner contact surfaces of the sprocket 2, there are rolling bodies 6. The outer ring 7 is also mounted on the shaft 1 with the possibility of rotation by means of radial bearings 8 and 9 and end caps 10 and 11 connected to bearings 8 and 9 by means of a press fit. Base covers are made in the covers 10 and 11, pressed into the ring 7, in which the permanent magnets 12 are installed, which are closed by the covers 13 and 14 above and below. The driven coupling half includes a shaft 15 connected to the cup 16 through the flange 17 by means of a key 18. Tightly connected with a flange 17, a cup 16, inside which permanent magnets 19 are mounted, is mounted on the shaft 15 with the possibility of axial movement with stops in the form of a retaining ring 20 and a washer 21, fixed to the end of the shaft 15 with a screw 22.

Description

The utility model relates to mechanical engineering and can be used in autonomous energy supply systems for transmitting unidirectional torque using a magnetic field between two vertical coaxial shafts operating at low speeds, separated by a sealed partition both under a pressure differential between the sealed cavities and under normal conditions.

Known freewheels ([1], p. 222).

The disadvantages of the above freewheel clutches include the presence of friction losses due to the presence of clamping devices, as well as the inability to transmit torque from the drive shaft to the driven shaft in sealed cavities.

Known electromagnetic couplings, which can be either shielded or unshielded, with a direct current excitation winding, designed to transmit mechanical motion in a non-contact manner using the magnetic force of the elements ([2], p. 10).

The disadvantage of the above electromagnetic couplings is the obligatory presence, for their operation, of an additional energy source with a control system, which makes them unsuitable when used in particular in autonomous power supply devices due to a decrease in the energy efficiency of the system as a whole.

Magnetic couplings of various types and designs are known for non-contact transmission of rotational motion, including into sealed cavities, between two coaxial shafts, which, according to a generalized structural criterion, depending on the distribution of forces acting on the coupling halves, are divided into axial ones (for example, SU patent No. 236155, F16D, dated 07.27.1966) and radial (for example, SU patent No. 1539917, Н02К49 / 00, dated 10.06.88).

The disadvantage of the above magnetic couplings is the constant adhesion between the driven and the leading coupling halves in their design through the magnetic field of the permanent magnets, which reduces the efficiency of transmission of rotation when the decelerating drive shaft begins to slow down and driven.

Known freewheel (SU No. 1732060, F16D41 / 06, 11/13/89) containing a clip, an asterisk, a separator with rollers mounted between them, spring-loaded relative to the sprocket, and a separator control mechanism made in the form of a concentric outer ring rigidly connected to the holder the clutch, and the inner disk, rigidly connected to the clutch separator, and permanent magnets are fixed on the surfaces of the ring and disk facing one another, and the magnets mounted on the surface of one of the elements are directed of the same name by the poles in the direction of another element on which the magnets are mounted by the same poles in the direction opposite to the rotation.

The disadvantage of the above coupling is that the design of the coupling does not provide for the transfer of mechanical motion in a non-contact manner into sealed cavities, which limits its application.

Permanent magnets mounted on the ring attached to the outer cage of the coupling half and on the disk, freely mounted on bearings on the shaft of the second coupling half, spring-loaded sprockets relatively rigidly fixed to the same shaft and rigidly connected to one end of the separator, act as a control member of the element due to the them during the rotation of the braking torque, which creates additional losses during operation, moreover, permanent magnets located on the outer ring on the ring and disk, seeking located opposite poles opposite each other will create an additional moment of moving.

The closest prototype in technical essence is a freewheel (SU No. 1318750, F16D41 / 07, 06/10/1985) containing the outer and inner rings, inserts made in the form of magnets with profile working surfaces and installed in the grooves of the outer ring and rollers made also in the form of permanent magnets placed in the space between the outer and inner clips and inserts.

The disadvantage of the above coupling is that the design of the coupling does not provide for the transfer of mechanical motion in a non-contact manner into sealed cavities, which limits its application.

High friction losses due to the fact that the magnetic rollers, for the clutch to operate correctly, must constantly contact the outer surface of the inner race and the magnetic, which, in turn, due to magnetic forces, will constantly slow down the rollers in an effort to fix them in a static position.

The design of the coupling places high demands on the tolerances, in the shape and roughness of the contacting surfaces, as well as on the tolerances of the diameters of the rollers, the outer diameter of the inner race and the inner diameter of the outer race, to their relative position, alignment.

Low reliability of the coupling due to the fact that all available magnetic materials have low strength and low wear resistance.

The purpose of the utility model is to expand the functionality of the freewheel.

The technical result of the utility model is to obtain the properties of a contactless unidirectional node, subject to the simplicity of the structural and technological design.

The goal is achieved due to the fact that the coupling consists of leading (inner) and driven (external) coupling halves located on two coaxial shafts, while on the outer ring of the driving and inner surface of the driven coupling half cup, opposite poles opposite each other, with alternating polarity, are located Permanent magnets, which provide constant coupling of two coupling halves for transmitting torque from the drive shaft to the driven shaft.

Inside the leading coupling half, inside its outer ring, freely seated on the shaft by means of two end caps and radial bearings, there is an asterisk rigidly connected to the coupling shaft. In the inner working contact surfaces of the sprocket, there are rolling bodies that provide coupling / uncoupling of the shaft with the coupling half ring when rotating counterclockwise / clockwise between the sprocket’s working surface / wedging and the inner surface of the ring. Above and below the sprocket are limiters. The lower limiter is mounted on the shaft of the driving coupling half freely on the rolling bearing.

The driven coupling half mounted on the shaft by means of a key (or spline) connection is made with the possibility of axial movement.

Figure 1 shows the coupling General view. Figure 2 shows the coupling a General view in section in vertical direction. Figure 3 shows the driven coupling half. Figure 4 shows the leading coupling half. Figure 5 shows the leading coupling half top view without displaying part of the details.

The coupling consists of a leading (Figure 4, Figure 5) and driven (Figure 3) coupling half mounted coaxially (Figure 1, Figure 2).

The leading coupling half (Fig. 4) comprises a shaft 1 with an asterisk 2 mounted on it over a press fit above and below which a fixed 3 and a movable 4 limiter rigidly connected to the sprocket are mounted, rotatably mounted and mounted on the shaft 1 by means of a bearing 5. Between the limiters , in the inner contact surfaces of the sprocket 2, there are rolling bodies 6 (Figure 4, Figure 5). The outer ring 7 is also mounted on the shaft 1 with the possibility of rotation by means of radial bearings 8 and 9 and end caps 10 and 11 connected to the bearings 8 and 9 by means of a press fit. In the lids 10 and 11, pressed into the ring 7, the base cutouts (Figure 5) are made, in which the permanent magnets 12 (Figure 4, Figure 5) are installed, which are closed at the top and bottom by the covers 13 and 14.

The driven coupling half (FIG. 3) comprises a shaft 15 connected to the cup 16 through the flange 17 by means of a dowel 18. The cup 16, rigidly connected to the flange 17, inside which the permanent magnets 19 are mounted, is mounted on the shaft 15 with the possibility of axial movement with stops in the form of a retaining ring 20 and washers 21 fixed to the shaft end 15 with a screw 22.

Rolling bodies 6 (Figure 4), asterisk 2 and limiters 3 and 4, in order to exclude the influence of the magnetic field of permanent magnets on them, are made of materials with low magnetic properties, such as ceramics, austenitic steels, nickel manganese cast irons, copper alloys, aluminum, titanium, etc.

The working contact surface of the sprocket 2 can be made not cylindrical, but cylindrical, eccentric with respect to the axis of the sprocket, profiled along a logarithmic spiral or have a different shape providing a more reliable operation of the coupling.

The coupling operates as follows.

The coupling can work with both a sealing cup 23 (FIG. 1, FIG. 2), mounted on the housing 24 of any device and made of non-magnetic material, and without it.

When the shaft 1 (Fig. 4, Fig. 5) is rotated counterclockwise, the rolling elements 6, the number of which can be more than three, are shifted along the working surface of the sprocket 2 to the inner surface of the ring 7 of the driving coupling half due to the occurring centrifugal forces wedge. Jamming occurs. As a result, the outer ring 7 begins to rotate together with the sprocket 2, the shaft 1 and the limiter 4 transmitting torque to the shaft 15 (Fig. 1, Fig. 2, Fig. 3) of the driven coupling half through the magnetic field of the permanent magnets 12 of the master (Fig. 4, 5) and 19 of the driven (FIG. 3) coupling halves.

The limiter 4 (Fig. 4, Fig. 5) being the supporting plane for the rolling elements 6, mounted on the shaft 1 of the driving coupling half by means of a radial bearing 5, when the shaft 1 and the sprocket 2 rotate counterclockwise, will remain in place or rotate in the direction coinciding with the direction of rotation of the shaft 1, but with a much lower angular velocity than the shaft 1 and the sprocket 2. As a result of the resulting speed difference between the shaft 1 and the limiter 4, the conditions for the displacement of the rolling elements 6 to a narrow part of the wedge are improved, and the time decreases clutch actuation, unlike if the limiter 4 were rigidly connected to the shaft 1 or the sprocket 2 of the drive coupling half.

When braking the shaft 1 of the driving coupling half, the driven coupling coupling, due to the resulting speed difference, the interaction force of the permanent magnets and the inertia force, rotates the outer ring 7, freely mounted on the shaft 1 through bearings 8 and 9 (Figure 4), the coupling coupling, relative to the sprocket 2, removing rolling elements 6 from the narrow zone of the wedge. The coupling halves disengage.

The lower limiter 4 (Figure 4, Figure 5), mounted on a radial bearing 5 on the shaft 1 and at the moment of engagement, the coupling half rotates with the shaft 1 with the same angular velocity, at the time of braking of the drive shaft 1, due to inertia, will tend to turn in the direction of rotation with an angular speed ahead of the shaft 1, creating an additional force for the withdrawal of rolling elements 6 from the zone of a narrow wedge.

The driven half-coupling (Figure 3), mounted on the shaft 15 by means of a key (or splined) connection, has the possibility of axial movement, which allows it to self-install, occupying an optimal equilibrium position in which there are no axial forces, which reduces the additional load on the bearing assemblies of the master and driven shafts, reducing friction resistance and allows you to transfer, due to the magnets being in the optimal area of mutual contact of magnetic fields, the maximum torque for these magnets.

To increase the transmitted torque in both coupling halves, magnets with a higher coercive force and a multi-row system installed in the driving coupling half consisting of additional sprockets and rolling elements can be used.

Claims (1)

A freewheel coupling, consisting of a driven coupling half containing a shaft, a cup, with permanent magnets mounted on its inner surface, and also a driving coupling half containing a shaft, sprockets with rolling bodies located in the area of its working contact surfaces, characterized in that the outer ring mounted on the shaft of the driving coupling half on two radial bearings by means of end caps between which permanent magnets are fixed along the outer perimeter of the outer ring, engaging with constant m by the driven coupling half by means of interaction of their magnetic fields, it is made to rotate both in the direction coinciding with the direction of rotation of the drive shaft when the sprocket adheres to the inner surface of the outer ring by rolling bodies, and in the reverse, freely when the surface of the ring and sprocket is disengaged, while the lower sprocket stop mounted on the drive shaft on the bearing is rotatably movable, and the driven coupling half is axially mounted on the shaft movement.

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