JPH01500288A - Continuously variable ratio transmission mechanism - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] 稗ロカ-Tsu-ratio-ΩBuddha medal machine wound Light - Higashi Higashi HΦi field The present invention relates to a continuously variable ratio transmission mechanism. More specifically, this mechanism 11 The first pulley with two conical flanges - supports the wheel [2 The drive shaft supports a second pulley wheel with two conical flanges with variable spacing. produces a magnetic field substantially parallel to the axis of the driven shaft and pulley wheel. The magnetic field of the straw passes over two booley wheels and the booley Each pulley wheel has a radius that varies according to the spacing of the flanges of the wheel. An endless transmission member such as a chain or belt of trapezoidal cross section wrapped around means for applying the flanges of the two pulley wheels in the wrapped area. The transmission member is wound around each pulley wheel. Transmit the magnetic field in the transverse direction so as to close the magnetic field by a part of the attached transmission part H It is suitable for.

Sad Autumn Street - A Shout-out It has two conical flanges with variable spacing, constituting a mechanical transmission. In two transmission mechanisms, an endless chain or belt is wound around two pulley wheels. The ratio of each wrapped radius determines the transmission ratio, and this ratio is According to the well-known principle ζ, the spacing between the two flanges of one pulley wheel is reversed. change the spacing between the two flanges of the other pulley wheel with a corresponding change in It can be changed continuously by changing.

Current transmissions of this type using belts or chains are purely f1! machine function and their efficiency depends on the flange of each pulley wheel. In order to insert (interpose) the transmission member between the pulleys and the transmission member – the energy required to separate the transmission member in the area of separation from the wheel. Therefore, it decreases. Efficiency is a function of the area in which the transmission member is wrapped around the pulley wheel. It is also reduced by friction in the area and by possible slippage. Currently, synchronous belt Fixed ratio transmission using chains and chains has an efficiency of 96-98%. Variable speed transmissions using surface belts have fairly low efficiency.

transmitting a magnetic field so as to obtain magnetic immobilization of the chain or belt relative to the flange; A transverse magnetic field closed through a chain or belt adapted to It has already been proposed to add this to the pulley wheels of this type of transmission. (see the document GB-A=2093151), In this case, the magnetic field is generated by an electromagnet and placed at each end of the pulley wheel. attached to the two flanges of the associated pulley wheels by means of magnetic pole pieces.

This type of magnetic circuit can be used with a chain or belt to increase the efficiency of variable speed transmissions. to improve the connection between transmission members such as bolts and each pulley wheel. Directed. However, the solution known from the document GB-A-2093151 does not give satisfaction, because on each side of the pulley wheel The two pole pieces placed cover an unchanging amount of the pulley wheel, so that The magnetic field is an arc that spans the area around the belt (this arc is the transmission due to the inherent principles of the operating equipment).

In the current situation where the magnetic field extends beyond the end of the wrapped arc on the pulley wheel. is the area where the chain or belt reaches the pulley wheel and There is a risk of the chain or belt becoming caught in areas where it comes off the rail. In particular, In the area where the belt or belt leaves the pulley wheel, it must be removed from the magnetic field. Naturally, this requires additional forces and reduces the overall efficiency of the transmission.

On the other hand, the magnetic field is spread over a circular arc over the area around which the chain or belt is wrapped. The current situation is that the wheel only extends over a sector of the pulley wheel which is quite small. In this case, the magnetic field does not serve optimally, so its overall efficiency is also compromised.

Moreover, in document GB-A-2093151, both pulley wheels are The two magnetic pole pieces placed at the ends change the distance between the two flanges of the pulley wheel. Follow. Therefore, the pole pieces must be able to move transversely, so A suitable means of guidance is required. The other critical factor in this is that the core of the electromagnet It must be made of two pieces connected to each pole piece. ; Therefore, when the two flanges move apart to change the transmission ratio, Magnetic forces must be overcome.

Even if all these factors are given, we can simply use the known electromagnetic solution. Efficiency improvements achieved through resolution methods are unrealistic.

Document GB-A-2093151 states that permanent magnets are attached to two flaps of a pulley wheel. Variants have also been described that are located directly on the lunges. Furthermore, the pulley wheel A similar arrangement involving a permanent magnet rotating with the wheel is described in document FR-A-1306716. has been disclosed. This solution works well with the circle around which the chain or belt is wrapped. A full rotation of the pulley wheel (360 It is clear that this leads to an annular distribution of the magnetic field extending over Always keep the chain or belt securely away from the pulley wheels. should not be.

The present invention aims to improve the method of applying magnetic fields by either electromagnets or permanent magnets. It is thus directed towards achieving an effective improvement in the efficiency of relation-type transmissions. Ru.

Kuhada @11 For this purpose, the invention provides a The pulley wheel can be moved in the angular direction according to the transmission ratio so that the Each pulley wheel is A magnetic field is created by means of a sector that is a good conductor of the magnetic field and is placed on each side of the wall. requires that a field be applied to the flanges of the two pulley wheels.

Therefore, the magnetic field applied to each pulley wheel is like a chain or belt. The magnetic field is continuously balanced on the winding arc of the endless transmission member, and the degree of the magnetic field varies depending on the winding of the transmission member. Vary according to the transmission ratio to maintain a very precise correspondence with the stuck area. child In this method, all snags detrimental to the operation are avoided, thus making it more effective. The rate increases significantly to values approaching 100%.

A pivoting sector is applied to the flanges of two pulley wheels by one means. Since the magnetic field is placed on the pulley wheel (as in prior art solutions) electromagnet or permanent magnet placed at a fixed location outside the pulley wheel It can be made by

Preferably the magnetic field is applied to a set of pulley wheels in the area around which the transmission member is wound. said pivoting sector over an angle at least slightly smaller than the sector; applied to each pulley wheel, resulting in a chain or belt It is certain that the magnets are not exposed to any magnetic fields in the arrival or departure regions.

Modified sector angle usage to balance the magnetic field to the wrapping arc of the transmission member. This can be done in a simple manner by means of a mechanical control system and in particular when the transmission element is In the case of a belt, this can be achieved using a tensioning device.

To obtain a well localized magnetic field oriented parallel to the axis of the pulley wheel Advantageously, the conical flanges of the two pulley wheels include radial slots. These slots make the flange smaller enough to obtain the required mechanical strength. divided into a number of small sectors separated from each other by sections of similar cross-section; These parts can be made of non-magnetic material to obtain overall magnetic isolation of the sectors. I can do it.

Assuming that the conical flange can move in the axial direction based on the inherent principle of the variable speed transmission. It is also necessary to ensure continuity of the magnetic circuit. For this purpose, useful Each flange is placed on its outer surface and on each side of each pulley wheel. Ring inserted at variable depth during arc-shaped complementarity in the pivoting sector Contains a state collector. This means that in the transverse direction to follow the flange Makes it unnecessary to provide sectors that can be moved.

In some known variable speed transmissions, a drive shaft and a driven shaft each have a pulley hole. It is fixed to the shaft with a key between the two flanges of the eel and is an endless transmission member. a disc designed to be inserted into a corresponding longitudinal groove formed on the inner surface (FR, -A-2414664 or (see document EP-A-0003198), preferably to reduce the magnetic field spread. It has a radial division to lower the By having the radial member such as a disc made of at least one part, the book The principles of the invention can be applied in a very advantageous way to this particular type of variable speed transmission. .

In this method, the connection between the transmission member and these discs at the wrap-around portion is Magnetic immobilization is also enhanced, which contributes to improved efficiency.

In one particular embodiment, in the case of a variable speed transmission using an endless chain, Place the chain links against the conical flange of the pulley wheel. Side plates that are good conductors of the magnetic field with matching sloped surfaces, and pulley wheels interposed between additional radial members such as disks that are keyed onto the axis of the All of these include an intermediate plate that is also a good conductor of the magnetic field and is designed to The plates are secured by at least one transverse coupling member that does not transmit a magnetic field.

This principle works by transferring mechanical power from one pulley wheel to the other by traction or thrust. Provides a chain for transmitting power to the pulley wheel.

Spaced apart from each other, extremely permeable to magnetic fields, and do not transmit magnetic fields Providing a belt having a side portion and a middle portion joined by a transverse linking member. By providing a transmission member of the same design, it is equivalent to a belt-type variable speed transmission. Applicable; even if this belt is of the “synchronous” type with a notched surface good.

In any case, the appendix shows various embodiments of this continuously variable ratio transmission mechanism. The invention will be further understood from the following description, given by way of non-limiting example with reference to the schematic diagram of Once understood, other features of the invention will become more apparent.

I-'IL song FIG. 1 is a highly schematic longitudinal sectional view of a variable speed transmission according to the invention.

Figure 2 shows the flange of the pulley wheel when viewed from the outside. FIG. 2 is a partial side view of the transmission from FIG. 1;

FIG. 3 corresponds to the lower part of FIG. 1 and provides this speed change transmission. 1 is a partial diagram showing a particular electromagnet that can be used for

Figure 4 shows the sector that directs the magnetic field onto the pulley wheel flange. FIG. 2 is a side view of another part of the transmission from FIG. 1;

FIG. 5 is a detailed cross-sectional view of a chain for a variable speed transmission according to the invention.

FIG. 6 is a side view of one chain arrangement applicable to the variable speed transmission according to the present invention. It is shown in

FIG. 7 shows another chain arrangement that is similarly applicable to the variable speed transmission according to the present invention. and its variants are shown in side view.

FIG. 8 shows the application of the present invention to a belt-type speed change transmission. This drawing is similar to the previous drawing.

FIG. 9 shows the line [-T 3 is a detailed cross-sectional view at X.

FIG. 10 is a partial longitudinal sectional view of this belt along the line X--X in FIG. 9.

Figure 11 shows an intermediate part forming part of one of the pulley wheels of the transmission. It is a partial front view of a disk.

FIG. 12 is a sectional view taken along the line ■--■ in FIG. 11, passing through the axis of the disk.

Figure 13 shows the details of this disc in an enlarged view and a cross section taken along the line X■-X■ in Figure 12. are doing.

FIG. 14 is similar to FIG. 12, but shows a section between the disks of an alternative embodiment. It is a front view.

Figure 15 shows an enlarged detail of this latter disk, taken along the line xv-xv in Figure 14. It is shown on the surface.

! LLVu 111-141 Theory - Tomo - Figures 1 and 2 show that the axes are parallel. 1 shows a variable speed transmission including a drive shaft 1 and a driven shaft 2. The drive shaft 1 is It supports a first pulley wheel 3 having two conical flanges 4 with variable spacing. . The driven shaft 2 is a second pulley wheel with two conical flanges 6 with variable spacing. 5 is supported. An endless transmission member 7, such as a chain or belt, connects the two -passes over wheels 3 and 5. The transmission member 7 is located between the two flanges 4. around the first pulley wheel 3 with a variable radius determined by the distance and two a second pulley wheel 5 with a variable radius determined by the spacing of the flanges 6 of the wrapped around. The ratio of both winding radii of the transmission member 7 determines the transmission ratio do. This ratio is calculated around point 9 located between the two pulley wheels 3 and 5. The pivoting lever 8 reverses the distance between the two flanges 6 of the pulley wheel 5. By changing the distance between the two flanges 4 of the pulley wheel 3, It can be changed more continuously.

In the embodiment shown here, the drive shaft 1 is fixed to the drive shaft 1 with a key. and a disc 1 inserted into a corresponding longitudinal groove 11 formed on the inner surface of the transmission member 7. 0 is supported between two flanges 4. In a similar manner, driven shaft 2 2 (Place the disc 12, which is fixed with a key and inserted into the 111, between the two frames. It is supported between lunges 6.

According to the invention, the flanges 4 and 6 of the two pulley wheels 3 and 5 and the circles The plates 10 and ]2 are made of a material that is a good conductor of magnetic fields. booleyhoinil A magnetic field parallel to the axis of the pulley wheel 3 and the pulley wheel 3 is a good conductor of the magnetic field and - hands in sectors 13 and 14 respectively arranged on each side of the wheel 5; It is applied to the flanges 4 and 6 by steps.

As shown in the upper part of FIG. 1, sectors 13 are "N" and " A magnetic field is created by permanent magnets 15 arranged in such a way as to constitute S" pole pieces. be able to. As shown in the lower part of FIG. A magnetic field can be created equally well by an energized electromagnet 16. Ru. More specifically, sectors 14 on one side, as shown in FIG. a central core 18 magnetically coupled to the center core 18 and a sector 14 magnetically coupled to the opposite side. Connected external armature = extremely low loss “bell” type electromagnetic including stone] 6 can be used.

The magnetic field created in this way is transmitted to the flanges 4 and 6. For this purpose each Flanges 4 and 6 of each are formed on their outer surfaces in adjacent sectors 13 and 14. It includes an annular collector 20 inserted into a complementary dipping 21. Shown in Figure 2. As shown, each flange 4 or 6 also features a number of radial notches 22. These notches divide the flange into many small sectors. These small sectors have an even smaller layer between them that ensures magnetic isolation. separated from each other by sections of cross section.

Still referring to FIG. 4, sectors 13 and 14 are arranged so that the transmission member 7 - arranged to distribute the magnetic field only in the area wrapped around the wheel 3 or 5; be placed. The sector of each pulley wheel 3 or 5 to which the magnetic field is applied is preferably Specifically, the transmission member 7 is wrapped around the relevant pulley wheel. The sector is oriented at an angle at least slightly smaller than the sector in question.

The transmission member 7 is adapted to transmit the magnetic field transversely. 1 chain link , a part of the transmission member 7 reaches a point of contact with one of the pulley wheels 3 or 5 , so when it comes into contact with flanges 4 or 6, that link is also exposed to the magnetic field. , and at this moment, the magnetic circuit, as indicated by the arrow in the drawing, Closed through sectors 13 or 14, flanges 4 or 6 and links.

The magnetic circuit through a particular link is such that the link is separated from flanges 4 or 6 and It remains closed until it leaves the wheel 3 or 5.

Therefore, the magnetism of the part of the transmission member 7 wound on the pulley wheels 3 and 5 is A pneumatic fixation is obtained, which means that the transmission member 7 and the conical surfaces of the flanges 4 and 6 The connection between the transmission member 7 and the discs 10 and 12 is also improved. Ru. As a result of this, transmission efficiency is improved. On top of that, pulley wheel 3 and and 5 are continuously adapted to the winding region of the transmission member 7, and the ring Optimizes transmission efficiency by ensuring that the contacts do not experience any forces at the contact points. be able to.

FIG. 4 shows the area where the transmission member 7 is wrapped around the pulley wheels 3 and 5. Within these wrap regions to take into account changes in the wrap radius to modify the angle of It shows how the magnetic field can be kept accurate. each sector 13 or 14 is mounted so as to pivot around the axis of the corresponding pulley wheel 3 or 5. It is. For small wrap radii, as shown in the upper part of Figure 4. Thus, sectors 1.3a and 13b are closed together. On the other hand, a large roll For radius, sector 14a is shown in the lower part of FIG. and 14b are separated from each other by angular relative movement. corresponds to that angle from one sector 13a or 14a to the other sector 13b or to one sector 13a or 14 to ensure continuity of the magnetic field to 14b. A is provided with a projection 23, which is connected to the other sector 13b or 14b. Fits snugly into the complementary recess 24 inside. Now, referring to FIGS. 5 to 7, the endless transmission member 7 is formed by interconnected links 25. Describe a variable speed transmission device that is a made chain.

FIG. 5 is a cross-sectional view showing a cross section of one link 25 of the endless chain 7. Ru. Links 25 connect to conical flanges 4 and 6 of pulley wheels 3 and 5, respectively. including an end member 26 in the form of a plate having an inclined outer surface designed to I'm here. A pulley is disposed between each end member 26 at a distance from each other. - Designed to be interposed between each of the discs 10 of wheels 3 and 5 and ]2. There is a series of intermediate plates 27. The intermediate plate 27 corresponds to the types of disks 10 and 12 used. Depending on the Can be characterized by concave surfaces (parallel surfaces or two convex conical surfaces) (see detailed explanation below). The end member 26 and the intermediate plate 27 are magnetic field Made of materials that are good conductors. All these members 26 and 27 are connected to the magnetic field. are secured by a transverse coupling member 28 made of non-conductive material. 2 consecutive The connection between the links 25 is effected by a connecting plate 29. Connect links to each other clips, springs, etc. to tie together to form a complete endless loop chain. Other connection means such as wires or the like may be equally suitable.

Generally speaking, changing the transmission ratio changes the winding radius of Chigon 7, which This requires a length offset or the occurrence of slip. Avoid the latter solution Therefore, a chip that performs its function by thrust, as shown in Figure 6, An advantageous solution to the problem of compensating the lengths of lanes 7 is adopted. Rem.

Between the two pulley-wheels 3 and 5, the links 25 of the chain 7 are normally Two types of concave travel, namely "thrust" travel 7a that transmits mechanical force and "loose" travel A run 7b is formed. If the transmission ratio is changed quickly, "sluggish running" 7b is the place! -/c, follow a straighter track, and do so in this manner. to cancel out the difference in radius during the change. Second, the routes for the two types of runs 7a and 7b. The chain 7 is usually concave in shape. wrapped around pulley wheels 3 and 5 of It is possible to make a tight angle more attractive.

Figure 7 shows that the function is achieved by traction, but fill mechanical force is not traction. 7 shows another endless chain 7 which is transmitted by the running of the chain i. spring 30 is placed between each link 25, so that the chain remains "loose". - The other run of n 7 takes a concave shape. In this case as well, the length cancellation is This is made possible by the concave slack running of the pin 7.

The main part of Fig. 7 shows that the link 25 of the chain 7 determines the basic winding diameter. The chains 7 are shown interconnected by the lower part, however , the lower part of FIG. 7 has the basic winding diameter toward the outside and the disks 4 and 6 It shows a deformed chain that is larger than the diameter, in this case link 25 ゛ are interconnected by their outer parts and also have springs 30゛ This spring normally keeps its slack run in a concave shape, and On the other hand, it provides length offset.

8 to 10 relate to a speed change transmission device in which the endless transmission member 7 is a belt. That strange thing The speed transmission device has a belt driven by a spring 34 wound around the driven shaft 2. A "floating" pulley with two rollers 32 and 33 applied to each run of 7. It includes a tensioning device 31, which tensions the rollers within an area limited by an abutment 35. There is a tendency to move 32 and 33 apart. The first roller 32 is a belt 7 is applied to the tension run, and the second roller 33 is applied to the slack run. It can be used. These rollers 32 and 33 are smooth or "synchronous" In the case of the shaped belt 7, it is a notched shape.

The tensioning device 31 provides length compensation during transmission ratio changes, if the torque If the wheel is reversed, the tensioning device 31 pivots around the driven shaft 2 and pulls the belt 7. Tension running becomes slack running. Furthermore, this tensioning device has a magnetic field according to the transmission ratio. This is used to command the modification of the angle of the Mechanical links connected to the sectors located on each side of the wheel wheels 3 and 5 This can be achieved in a simple way by linking devices.

Figures 9 and 10 show the detailed till behavior of the "synchronous" type belt 7. The toe 7 includes a side portion 36 and a middle portion 37 projecting from an inner surface thereof. All of them are highly permeable to magnetic fields. The side portion 36 is the conical flanges 4 and 6 of the wheels 3 and 5, respectively. It has a sloped outer surface designed to The intermediate portion 37 spaced between the It is designed to be interposed between each of the discs 10 and 12 of the Lee wheels 3 and 5. Ru. All these parts 36 and 37 are connected by transverse coupling members 38 which do not transmit magnetic fields. It is fixed. The vertical strength of 7 is due to the wire embedded in the belt. -39. Finally, the belt 7 has a notch 40 on its inner surface. Two.

Finally, Figures 11 to 15 show parts of the pulley wheel 3 or 4 in various embodiments. The detailed structure of the forming intermediate disk 10 or 12 is shown: Figures 11 and 12 show a disk 10 or 12 with parallel surfaces. That is an example For example, a magnetic field impermeable frame attached to a rigid steel column 42 by electron beam blast welding. 4). Made of rubber or plastic filled with magnetic material such as iron powder An elastic member 43, such as a member, is overmolded onto the two surfaces of the rigid member 42.

As shown in Figure 13, reducing the spread of the magnetic field to limit magnetic losses In order to achieve and a large number of those parts can exist at the same radius. magnetic field These “barriers” to chain types as shown in Figures 5-7 In the case of a variable speed transmission, it corresponds substantially to the pitch of the links 25 of the chain 7. There must be.

FIG. 14 shows a disc 10 or 12 with two convex conical surfaces. That's ha 46. Two slightly conical sheet metal washers -47 and their two washers - Made of an elastic intermediate material F148 filled with magnetically permeable particles arranged between It is. As shown in FIG. 15, these two washers 47 The washer 47 may include interlocking teeth to transmit the field. The thinner regions covered avoid the spread of the magnetic field. The washer 47 is secured by a stop shaft means. and rotationally coupled to hub 46.

In all cases, part of the chain link or belt contacts the contact point on the pulley wheel. At times, the disc 10 or 12 with the elastic portion as described above is provided with a mechanical interface. Slightly pressed so that there is no response time due to the rear; When used, the magnetic field is closed through all discs 10 or 12.

The variable speed transmission according to the invention can be operated dry or lubricated, as appropriate. I can do it.

As will be apparent, the invention relates to the continuously variable ratio transmission mechanism embodiments described above by way of example. On the contrary, the present invention is not limited to structural details. without including all variations consistent with the same general principle. In particular, the scope of the invention Changing the arrangement (periphery or sides), number or shape of permanent magnets or electromagnets that create the field The essential fact is that the magnetic circuit is not established. That is.

FIG, 12 FIG, 1'l FIG, 14 International Search Report ANNEX To T! (E rNTERNATIONAL SE entrance C8P L? ORT ON

Claims (14)

[Claims] 1. drive shaft; a first on the drive shaft comprising two conical flanges of variable spacing; Pulley wheel; driven shaft; comprising two conical flanges of variable spacing; a second pulley wheel on the driven shaft; an endless transmission member adapted to transmit the field in the transverse direction, in which case the transmission ratio is The spacing between the flanges of each pulley wheel changes, thereby causing the transmission member to is wrapped around each pulley wheel by changing the wrapping radius. means for creating a magnetic field substantially parallel to the axis of the pulley wheel; ; applying the magnetic field to the pulley wheel in the area where the transmission member is wound; A sensor, which is a good conductor of the magnetic field, is placed on each side of each pulley wheel to sector-shaped member, in which case the magnetic field is closed by the transmission member and the sector-shaped member the shaped member is adapted to pivot about the axis of the pulley wheel; and the pulley wheel around which the sector-shaped member is always wrapped around the transmission member. the sector-shaped member in response to changes in the transmission ratio so as to precisely correspond to the rolling area. a continuously variable ratio transmission mechanism including means for swiveling the 2. the rotating sector-shaped member contained in a magnetic circuit including the sector; a permanent magnet creating a magnetic field applied to the flange of the pulley wheel by means of a permanent magnet; The transmission mechanism according to claim 1, comprising: 3. the rotating sector-shaped member contained in a magnetic circuit including the sector; an electromagnet that creates a magnetic field applied to the flange of the pulley wheel by means of The transmission mechanism according to claim 1, comprising: 4. The transmission member is wrapped around the pulley wheel in a sector magnetic field by said pivoting sector means over at least a slightly smaller angle. 2. The transmission mechanism of claim 1, wherein a field is applied to each pulley wheel. 5. The sectors are on each side of the pulley wheel, one sector and the other. at least one sector with protrusions to create continuity of the magnetic field to the sector and other sectors comprising complementary recesses in which said protrusions interlock closely. The transmission mechanism according to scope 1. 6. the conical flange of the pulley wheel includes a radial slot; The holes are separated from each other by sections of smaller cross-section and/or made of non-magnetic material. The transmission mechanism according to claim 1, wherein the transmission mechanism is divided into a large number of small sectors. . 7. Each conical flange includes an annular collector on its outer surface, and each pool The sectors on both sides of the lee wheel include arc-shaped complementary grooves, and the annular collector 2. A transmission mechanism as claimed in claim 1, wherein the gear is inserted into the complementary groove at a variable depth. 8. between the flanges of each pulley wheel on the drive shaft and the driven shaft; including an additional radial member keyed to the transmission member and a corresponding longitudinal groove in the transmission member. and the additional radial member is inserted into the groove, and the additional radial member has at least Some are made of materials that are good conductors of magnetic fields and, in some cases, Further divided in the radial direction to contribute to magnetic fixation of the wrapped portion of the transmission member The transmission mechanism according to claim 1, wherein the transmission mechanism is 9. The additional radial member is an elastic member filled with magnetic material. The transmission mechanism according to claim 8. 10. The transmission member is an endless chain made of individual links, and the links are an inclination adapted to be abutted against said conical flange of the pulley wheel; A side plate that is a good conductor of the magnetic field and has an inclined surface, and a side plate that is also a good conductor of the magnetic field and The drive shaft and driven shaft supporting the pulley wheel are fixed with keys. an intermediate plate adapted to have additional radial members interposed thereon, on which a magnetic field is applied; The claimed invention includes at least one transverse connecting member that does not communicate and secures all said plates. The transmission mechanism according to scope item 8. 11. The links of the chain are adapted to operate under traction or thrust. At least one concave run is formed between the pulley wheels, and the transmission ratio is changed. The transmission according to claim 10, adapted to allow a cancellation of the length during movement mechanism. 12. The transmission members are separated from each other and highly permeable to magnetic fields. the side portions and the middle portion of the 9. The transmission mechanism according to claim 8, which is a belt included together with a connecting member. 13. two rollers applied to each run of the belt, and the rollers Assemble springs adapted to propel them apart from each other and into contact with the belt. 13. A transmission mechanism as claimed in claim 12, including a "floating" tensioning device incorporating a "floating" tensioning device. 14. The aforementioned angular displacement of the sector on each side of the pulley wheel is of the appeal carried out by said tensioning device, possibly by mechanical coupling. The transmission mechanism according to scope item 13.