MXPA00006127A - Drive mechanism for infinitely-variable-transmission - Google Patents

Abstract

A drive mechanism for an infinitely-variable-transmission in which a relatively flexible member (32) connects one or other of the discs (14) to the shaft (10), thereby to accommodate a degree of shaft flexing without distortion of the toroidal cavity.

Description

MECHANISM OF IMPULSION FOR AN INFINITELY VARIABLE TRANSMISSION The present invention relates to a transmission device of infinitely variable ratio, of the rolling friction type, of a toroidal guide ring, which will be handled hereinafter as a speed variator. In such an apparatus a main arrow is used, which takes impulse from, for example, a motor, for example, an internal combustion engine; and transmits it to two input discs which are mounted on the arrow. Two output discs are mounted back to back between the input discs, and are free to rotate in relation to the arrow. In such an arrangement, the movement is transferred from the input discs to the output discs, via a plurality of rollers placed in toroidal cavities; which are provided between the input disks and the output disks.

REF .: 120722 Speed variators are also known, single cavity, in which a single input disk is mounted, for rotation on an input shaft, and a single output disk faces the input disk in such a way which defines a toroidal cavity, in which a plurality of power transmission rollers are located. While such an arrangement is less likely to be affected by the problems described herein, it will be appreciated that the present invention can be applied to this single cavity arrangement. The rollers are subjected to hydraulic forces by an extreme load device, such that they have contact with the faces of the respective inlet and outlet discs to transmit power from the inlet discs to the outlet discs. The power is transmitted from the output discs, via, for example, a pulse chain to an additional transmission component such as a gear box or speeds ep i c i c 1 or i da 1.

The impulse through the chain exerts a transverse load on the arrow and, the high power transmission levels, can cause the arrow to bend. The degree of bending is relatively small, but it has the potential to cause a significant effect on the position of the output discs, which causes the load on some of the rollers to increase, ie, an oppression effect is applied, while the load on __some of the remaining rollers decreases, which does not allow an efficient transfer of impulse from the input discs to the output ones. It will be appreciated that, the effect of the arrow bending, is due to a distortion effect of the toroidal cavities between the inlet and outlet discs. A solution to the above problem can be summarized by accepting a relatively small degree of flexion of the arrow, and subsequently providing some elasticity in the mounting of the discs, so that when the arrow is subjected to bending or bending, the discs can rotate in planes that are parallel to each other, and thus maintain the shape of the cavities. GB-A-436363 discloses a variable speed power transmission mechanism; which has some discs and rollers in which, one of the discs is mounted on a support arrow, this by means of one or more teeth or safety, on a front face which fits or fits with a collar fixed to the central arrow. Such an arrangement effectively provides some degree of relative movement between the disk and the arrow, but the improvement of this design is possible. The present invention seeks to provide a transmission apparatus, in which one or more of the disks is mounted on the arrow in such a way that they rotate with the arrow, but that is also capable of adopting a plane of rotation that is different from the normal . Accordingly, the present invention provides a transmission apparatus, variable speed drive, comprising an input shaft, one or more input discs mounted on the arrow to rotate with it, an output disc assembly, the disc or input discs and the output disc assembly define between them, one or more toroidal cavities, a plurality of rollers located in the cavity or cavities, and means for applying an extreme load pressure, to keep the rollers in contact with the respective disc or discs, so that impulse is transmitted, characterized in that one of the discs is mounted on the disc. arrow by means of an intermediate member, relatively flexible. The relatively flexible member can be attached to a bushing at an internal radial location, and the bushing is attached to the arrow so that it can rotate therewith. For example, the bushing can be grooved, in such a way that it is rotary with the arrow, and can be moved axially in relation to the arrow. The relatively flexible member can be attached to the bushing by a clamping ring.

The flexible member may be attached to a clutch ring, in an outer radial location. The clutch ring can be provided with prtions that can fit with the corresponding depressions in said disc; alternatively, the disc can be provided with prtions which can be fitted with the corresponding depressions on the embr-e ring. The relatively flexible member can be secured to said external radial location, by means of an external clamping ring.

A reaction plate can be mounted on the arrow, with the reaction plate having two or more sets of pins, one such set of pins can be extended through the openings of the free spaces in the flexible member, this for having contact with one face of the already said one of the disks, the pins of one of the other sets of pins may fit with the relatively flexible member in an internal radial location. The apparatus may include a clamping nut assembly, which is mounted by its threading on the arrow, for the purpose of forcing the reaction plate to have contact with the aforementioned one of the disks by means of the aforementioned one of the sets of pas ado res. The other of the aforementioned discs can be mounted for rotation with the arrow, and be provided with stop means to prevent their axial movement. The output disk assembly can be mounted on bearings, which have spherical part cooperation surfaces, which allows the disk assembly to rotate in relation to the arrow, and adopt the plane of rotation which is other than the normal in relation to the arrow. In a development of the above, the flexible member can also be secured to the reaction plate, from the loading mechanism ext rema.

In developing the above, the flexible member can be secured to the reaction plate and the sleeve, this by means of a bolt array or rivet arrangement. In either arrangement, the flexible member can be secured to the disk by means of an array of bolts or rivets. In yet another development, the flexible member in either of the two arrangements may be preformed or pre-loaded, such that from the application of the extreme load, it is substantially perpendicular to the axis of said arrow. The present invention will now be described more particularly with reference to the accompanying drawings, in which: Figure 1 shows a diagrammatic representation of an apparatus, of transmission, of infinitely variable proportion, of the type in which the present invention; Figure 2 shows a view with the separated parts of a disk assembly form in accordance with the present invention; Figure 3 is a section on the line A-A of Figure 2; Figure 4 is a section on line B-B of Figure 2; and Figures 5 and 6 are sectional views of an alternative embodiment or form of the present invention.

With reference to the drawings, there is shown an apparatus for the transmission of a finitely variable ratio, of a speed variator; which comprises an input arrow 10, two input discs 12, 14; two output discs 16, 18, two sets of rollers 20, 22 which are located in the toroidal cavities 24, 26, which are formed between the inlet and outlet discs, and an impulse chain 28 which is mounted on the two output discs 16,18. The two input discs 12, 14 are formed to rotate with the arrow 10, for example, by means of slotted assemblies, while the output discs 16, 18 are free to rotate relative to the arrow 10.

The input disk 14 has a limited axial movement, and the disc 12 is prevented by means of a stop, not shown, on the arrow 10, of the axial movement on the arrow. The disk 14 is subjected to an operating load to the left as shown in figure 1, for example, by means of hydraulic pressure, in such a way that the sets of rollers 20,22 are kept in contact with the toroidal surfaces of the inlet and outlet discs, which allows the impulse to be transmitted from a power source, for example, an internal combustion engine, via an impulse chain 28, to an additional component of the transmission of a vehicle, for example, an epicyclic gearbox not shown. As will be appreciated, the impulse chain 28 can exert a bending load on the arrow 10, and therefore a distortion in the shape of the toroidal cavities 24,26 can be caused. Thus, it will be appreciated that the loading of some of the rollers 20,22 will be increased while the load of the remaining rollers will be distorted. The increase of the load in some of the rollers can be unacceptable, since the excessively high tensions are caused inside the rollers, while in the load of the remaining rollers in the same way, the efficiency of the impulse between the discs is reduced input and output, since a slip between the input and output discs may occur. To prevent or substantially reduce the effect of the distortion of the shapes of the toroidal cavities 24,26, which can be produced by a bending load applied to the arrow 10; the present invention proposes a design that allows the input and output discs to adopt rotational planes which are and remain substantially parallel one. to another when the bend is presented. With reference to Figures 2,3 and 4, there is shown an assembly 30, which allows the disc 14 to be mounted to rotate with the arrow 10 in order to transmit impulse, but also to allow the plane of rotation of the discs be other than normal, that is, perpendicular, to the arrow 10. The assembly 30 comprises a relatively flexible member, for example, a diaphragm 32, which is joined at a radial internal location to a slotted bushing 34 by means of a clamping ring 36, and screws 38, the slotted bushing 34 extends through a free space of the internal diameter in the center of the disk 1.4. The relatively flexible member is, in particular arrangement, made in a pressure form of a screw steel sheet (for example, screw steel with BS 1449: CS80). Other appropriate alternatives will, however, be present by themselves to persons skilled in the art. The bushing 34 is axially movable on slots formed on the arrow 10 and the axial movement of the bushing 34 is limited by a rim 40, formed on the arrow 10. As shown in figures 3 to 6, between the disk and the arrow , an opening G is provided, with which to accommodate the desired relative movement. In an external radial location, the diaphragm 32 is joined to a clutch ring 42, this by means of a clamping ring 44 and the screws 46. The clutch ring 42 is formed on its circumference with rectangular teeth 48, which engage with the corresponding teeth 50 which are provided on the circumference of the disk 14, for example, in the form of a hook or grip clutch. The engagement between the teeth 48 and the teeth 50 allows the impulse to be transmitted from the diaphragm 32 to the disc 14, and further locates the disc 14 with respect to the arrow 10. It will, of course, be appreciated that the disc can be Provide with projections, which mesh with the corresponding depressions in the clutch ring. A circular reaction plate 52 is mounted on the arrow 10 and carries two sets of pins 54,56. The pins are mounted in flared holes 58,60 respectively in the plate 52. Each of the sets comprises two pins, but if it is required more pins can be used. The assembly 30 is previously loaded by means of a nut sub-assembly 62, which comprises a nut 64 and a securing plate 6 6 which is screwed to the nut 64. Between the nut 64 and the plate 52, a Belleville type washer 68. The rotation of the nut 64 applies pressure via the Belleville 68 washer to the plate 52, and the pins 56 engage with the openings in the clamping ring 36, such that the plate 52 rotates with the diaphragm 32. At the same time, the pins 54 pass through the openings of free space in the diaphragm 32, in contact with the front face of the disc 14. Once the assembly in this way has been previously loaded, the clamping ring 66 is secure in its position to prevent rotation of the nut 64.

It will be appreciated that the disk 14 is previously loaded, such that the rollers 22 in the cavity 26 have contact with the input disk 14 and with the disk of s on the first 18.

It will also be appreciated that, since the teeth 48 of the clutch ring are engaged with the teeth 50, of the outer circumferential surface, of the disk 14; the impulse can be transmitted from the arrow 10 to the disk 14.

The assembly 30 also includes a housing 68, and a lid 70 at one end, which are joined in a position by means not shown.

The arrow 10 includes an opening 72 to allow the hydraulic pressure to be applied to the space defined by the rear face of the disk 14, and the front face of the plate 52. The diaphragm 32 is provided with openings, so that the fluid Hydraulic can fill this space. The applied hydraulic load forces force the bushing 34 into contact with the stop 40, so that there is a clearance between the disk 14 and the diaphragm 32.

To contain the hydraulic fluid within the desired volume, the assembly is provided with seals S. It will be understood that when the arrow 10 is subjected to a bending, the relatively flexible diaphragm 32 can bend as the disc 14 rotates, thereby not only the impulse is allowed to be continuously transmitted from the arrow 10 to the disk 14 but also the shape of the toroidal cavity 26 is maintained. In addition to the disk 14 thus assembled, the disk 12 can be assembled in a conventional manner, example, by means of a grooved arrangement, and with a stop to prevent the movement of the disc 12 being more to the left, as shown in figure 1; such that when the arrow 10 is subjected to bending with the plane of the disk 12, it will remain normal with the axis of rotation of the arrow 10. Obviously, one can mount the disk 12 in the same manner as described in connection with the disk 14.

Some flexibility may be provided for the discs 16, 18; this by mounting the discs on a bearing, in which the surfaces cooperate as spherical parts, which would allow the output discs 16, 18 to adopt a plane of rotation which is different from the normal with the axis of rotation of the arrow 10. It will be appreciated that the above arrangement can be reversed in such a way that the input discs 12, 14 become output discs, and the output discs become input discs. In addition to this, it will be appreciated that the present invention can be used as a single-cavity speed variator, in which the bearing bears in such a manner that bending of the shaft is a possibility. It will be an additional appreciation that, when using a dual cavity variator; one must, if desired, provide a bending or bending impulse in both disks, say the input and the output. In figures 5 and 6, an alternative to the above is shown, which are each seen in cross section, taken at slightly different angles, in order to illustrate the complete components of the bending or bending impulse. In this arrangement, the similar components that have been given with the same reference numbers as in figures 3 and 4, are not necessarily mentioned here. In the alternative arrangement, the disk 14 is still mounted or middle of a relatively flexible member 32, but this member is secured in a slightly different manner. For example, the outer ends of the member are secured to the discs by blind rivets 100, which act by securing the member 32 between a pair of clamping rings 102, 104, and with the disc 14. A plurality of such rivets are circumferentially spaced apart. around the outer circumference of member 32, and collectively provide sufficient force to ensure torque transmission through the connection. The inner end of the member 32 is again secured to the slotted bushing 34, but this is also secured to the reaction plate 52. In the specific example, a plurality of bolts 106 extend through the bushing 34, the flexible member 32 and into the reaction plate 52, in which portions are provided threaded 103 for receiving a thread 110 in the bolts 106. A reverse arrangement can be used, in which the bolts pass through the reaction plate and can be screwed into the bushing 34. In a preferred arrangement, the member flexible, preformed or pre-loaded, so that once it is applied with the extreme load, it adopts a position in which it is substantially perpendicular to the arrow, and only deviates from this, if the arrow is subjected to bending or bent. Indeed, the arrangement is such that, at rest, the central portion of the flexible member of figure 5 and the sleeve 34 move toward the cavity, this by an amount equal to which the disc 14 will move once apply the hydraulic load. The arrangement of Figure 5 in the position associated with the full hydraulic head load, and the reaction plate 52 is shown displaced away from the disk 14, such that it abuts against the lock nut 64. Before it is apply the hydraulic extreme load, the spring 68 acts to load the disc and in this way form a small opening, not shown between the reaction plate and the lock nut 64. It is this opening that accommodates the required movement, when applied the extreme hydraulic load. It is noted that with respect to this date, the best method known by the applicant to implement the said invention is that- is clear from the manufacture of the objects to which it refers. Having described the invention as above, property is claimed as contained in the following:

Claims (17)

1. An apparatus for the transmission of a variable speed drive comprising an input shaft, one or more input discs mounted on the shaft for rotation therewith, an output disc assembly, the disc assembly (s) outlet disc define between them one or more toroidal cavities, a plurality of rollers located between the cavity or cavities, and means for applying an extreme load pressure to keep the rollers in contact with the respective disc (s), e_to with the purpose of transmitting impulse; characterized in that one of the discs is mounted on the arrow by a relatively f lexible member.

2. An apparatus as claimed in claim 1, characterized in that the relatively flexible member is attached to a bushing at an internal radial location, and the bushing is attached to the arrow such that it is rotatable with the latter.

3. An apparatus as claimed in claim 2, characterized in that the bushing is grooved, such that it is rotary with the arrow and axially movable relative to the arrow.

4. An apparatus as claimed in any one of claims 1 to 3, characterized in that the relatively flexible member is joined to the bushing by means of a clamping ring.

5. An apparatus as claimed in any one of claims 1 to 4, characterized in that the relatively flexible member is attached at an external radial location to a clutch ring.

6. An apparatus as claimed in claim 5, characterized in that the clutch ring includes projections, and the disc includes corresponding depressions so that the projections can mesh with the corresponding depressions in said one of the discs.

7. An apparatus as claimed in any one of claims 1 to 6, characterized in that the relatively flexible member is secured to the external radial location by a clamping ring e e rno.

8. An apparatus as claimed in any one of claims 1 to 8, characterized in that it also includes a reaction plate mounted on the arrow, the reaction plate has two or more sets of pins, one such set of pins is extendable through of the free space openings in the flexible member, this to have contact with one face of the said one of the disks, the pins of one of the other sets of pins, fits in relation to the flexible member in an external radial location.

9. An apparatus as claimed in claim 8, characterized in that it also includes a clamping nut assembly, which is threadably mounted on the arrow, this in order to force the reaction plate to have contact with the aforementioned one of the discs by means of the respective one of said pasado games.

10. An apparatus as claimed in any one of claims 1 to 8, characterized in that the other of said discs, is mounted for rotation with the arrow, and includes a means to stop, this in order to prevent movement axial.

11. An apparatus as claimed in any one of claims 1 to 10, characterized in that the output disk assembly is mounted on bearings, which have spherical cooperating surfaces thereby allowing the disk assembly to rotate in relationship with the arrow, and to adopt a plane of rotation different from the normal in relation to the arrow.

12. An apparatus as claimed in claim 1, characterized in that the flexible member is secured to the reaction plate of the extreme loading mechanism.

13. An apparatus as claimed in claim 12, characterized in that the flexible member is secured to the reaction plate and the bushing by means of a bolt array or rivet arrangement.

14. An apparatus as claimed in any one of claims 1 to 13, characterized in that the flexible member is secured to the disk by means of an array of bolts or a set of rivets.

15. An apparatus as claimed in any one of the preceding claims, characterized in that the flexible member is preformed or preloaded in such a way that once the extreme load is applied it is substantially perpendicular to the axis of said arrow.

16. An apparatus as claimed in any one of the preceding claims, characterized in that the speed variator comprises two input discs and the output discs, the output discs are placed back to back and are interspersed between the two input discs.

17. An apparatus as claimed in any one of claims 1 to 15, characterized in that the speed variator comprises two input discs and two output discs, the input discs are placed back to back and are interspersed between the two output discs .