TECHNICAL FIELD

The invention is related to motor vehicles with at least one car driving axle where the torque from the engine, transmitted to the wheel axle via input drive gear, must be split to two output shafts (half-axles) of axle driving wheels. During movements of driving axle wheels, it is also necessary to manage situations when vehicle drives in bends, each wheel of axle runs a different length of route, and this means that wheels rotate with different number of rotations. A gear mechanism - axle differential was used for smooth and problem free driving of wheels with different number of rotations on axle from one engine. Moreover, if a vehicle has two car driving axles, wheels of individual axles will have different routes, so along with two car driving axles differentials, one in each car driving axle, it will be also necessary to use the third differential, called the inter-axle differential, to split the torque from the engine shaft to two car driving axles.

Differentials, except usual driving of vehicle in bends, have also to deal with situations in which, because of terrain or weather conditions, one driving wheel has lower adhesion due to ice, mud below the wheel or in a dissected terrain a wheel lifted into air, without any contact to the underlying terrain. In such conditions, the usual open differential will have a problem to provide necessary torque for wheels on rigid terrain because the split torque will rotate only the wheel with lower adhesion and the other driving wheel would not receive necessary torque, so the vehicle cannot apply the engine torque to the underlying terrain for vehicle drive away. This invention, designed exactly for managing of the above-mentioned situations of lower adhesion, is usable not only as the axle differential but also as the inter-axle differential.

This proposal uses transformed worm gear, which in addition to the pennanent differentiating of different rotations of the two output drive gears in bends, by own suitably applied natural selflocking of the worm gears will provide maintaining of adequate rotations of car driving axle wheels, also in case of lower or total loss of adhesion of one of the driving wheels to the underlying terrain. BACKGROUND ART

There were efforts made during the entire automobile era, from the moment of finding the imperfections of the open differential, to design a differential able to provide drive of both output drive gears in different adhesion conditions of the vehicle wheels. Proposals were based on different principles, from mechanisms of the complete differential blocking (both output shafts mechanically coupled and rotating together with identical number of rotations), via linking of output shafts using different couplings (mechanical, frictional or viscous), even up to the application of worm gears with different forms and levels of use of their possible self-locking and/or increased friction of used gears, in order to limit slipping of the driving wheel with low adhesion.

Based on my own research of differential solutions on the Internet, I have discovered six relevant documents from different countries, in which I have found partial match with my solution. The following list presents their identification data as well as short characteristics:

1. US 1213258 (y. 1917, Reddig) - used flat spiral discs without toroidal forming, thus reducing the number of simultaneously meshing teeth of the toothed satellite wheels, by that reducing the scale of potential of transmitted power.

2. US 1352910 (y. 1920, Ormsby) - planetary discs have discontinuous spiral teeth, satellites also have teeth, formed for the right as well as for the left thread of planetary wheels, representing more complex production and limitation of power.

3. EP0332542A1 (y. 1988, Seris) - proposed flat discs with spiral groves without toroidal forming, thus reducing the number of simultaneously meshing teeth, and satellite wheels with fixed teeth, formed into the hemispheric shape or ball surface parts for meshing in spirals.

4. RU2351820C 1 (y. 2007, Kovafcuk)) - flat discs without toroidal forming, reducing the number of simultaneously meshing balls, and satellite rotating chains of mechanically unfastened balls reducing the height of teeth in meshing, while the freedom of balls in mutual contact in chains could cause different uncertainties of their mutual acting during movement in grooves and sleeves.

5. RU74989U1 (y. 2008, Kovafcuk) -planetary discs with grooves embrace radially rotating chains of unfastened balls in carrier grooves, while balls in the tangential direction pressed by sleeves with round fronts, but similarly as in the previous proposal, the freedom of balls in chains in mutual contact could cause different uncertainties of their mutual acting during movement in grooves and sleeves. Balls in chains with mutual contact (identically with the previous solution) will cause transfer of the forces between balls and groove walls, not only in places with the largest ball diameters, but also in places nearer to the ball tops, which in relation to ball rounding will generate large undesirable pressures on the groove walls and edges.

6. AT507731B1 (y. 2014, Muehlbacher) - satellite wheels with teeth in the form of truncated cones and flat discs with spiral grooves with profiles adjusted to teeth of wheels, will generate components with extraordinarily complex surfaces and estimated highly demanding production.

The submitted invention presents a new approach of use of the principles of worm gear in differential, where by using different balls for bodies, teeth, and as well as replacement of shafts of rotational beddings of the satellite worm wheels, will substantially reduce the complexity of the differential production, because these components have an uncomplicated production, balls are available on the market in a broad assortment of dimensions, material and strength for minimum prices.

Application of the principle of toroidal shape of the working area of planetary worms, adjusted for perimeters of the satellite worm wheels, will provide simultaneously the maximum number of teethed balls meshing, and at the same time, there is no need to use any fixation of tooth-balls in beddings of carrying balls of the satellite worm wheels, where tooth-balls are simply by their halves inserted in hemisphere beddings. The tooth-balls during meshing are maintained in their locations by spiral thread grooves of the toroidal planetary worms, and outside the meshing with the planetary worm, when the tooth-balls pass through the carrier body to the other side of the carrier, these tooth-balls are maintained in their beddings via small channels in the carrier body, also shaped according to imaginative toroid created by tooth-balls during rotation of the satellite wheel.

DESCRIPTION OF THE INVENTION

The purpose of the new arrangement of the differential is to provide in different unfavourable conditions, the options to use the torque on one output shaft (half-axle of the car driving axle) that will not have an impact on use of the necessary torque on the other output shaft.

For that purpose, the insertion of worm gears between input and output shafts was designed, because the worm gear is characterised by the fact that for a suitable harmonisation of the design parameters, the set of worm and worm wheel will become self-locking, when in one direction of drive the worm can drive the worm wheel, but in the opposite direction the worm wheel cannot drive the worm, thus it is impossible to reverse the drive direction (between the input and output shafts).

Worm wheels are placed in a form of satellites in passing through holes of the disc carrier, placed in a circle on identical radius from the axis of the carrier disc rotation, where the carrier represents a basic part of the differential body, powered from the input shaft. The disc of the satellite carrier is rigidly connected to the differential body and together rotating around an axis, which is also identical with rotation axes of the output shafts. Rotation axes of the satellite worm wheels, located in the carrier, are tangential to a circle described by centres of these satellites during rotation of the satellite carrier disc.

Two planetary worms provide mechanical drive from the satellite worm wheels to output shafts of driven wheels. They are located on both sides of the satellite carrier disc, with slipping contact with the carrier by their flat front areas. These two planetary worms, mounted on splining of output shafts (half-axles), and together with half-axles, rotate around the common axis with the carrier disc.

Satellite wheels bodies placed in the carrier are created from large carrying balls, with diameter larger than thickness of the satellite carrier disc, so by parts of their volume, these balls stand out of the carrier side planes. In order that planetary worms on both sides of the satellite carrier could by their flat surfaces adhere with slip to flat surfaces of the carrier disc, and not collide with carrying balls of the satellite wheels standing out from the carrier side planes, therefore planetary worms have designed in their flat surface adhering the satellite carrier disc a circular gutter with the shape of side cut-off of the toroid, rendered down by carrying balls of the satellite wheels from the carrier. By this a layout was created, where the standing out parts of carrying balls of the satellite wheels (except tooth-balls) by their perimeter tightly adhere to surfaces of the toroidal gutters on planetary worms.

To create a mechanical drive between satellite worm wheels in the carrier and toroidal planetary worms, satellite worm wheels have mounted on their perimeter smaller steel balls as wheel teeth, where by one half of their volume, these tooth-balls mounted in designed hemispheric beddings with regular spacing on the perimeter of the carrying ball of the satellite worm wheel, and by the other half, standing out of the carrying ball of the satellite wheel, these balls create teeth of the satellite worm wheel, for meshing in grooves of the toroidal planetary worms. Worm grooves formed with a semi-circular cross-section for meshing of tooth-balls of the satellite worm wheels with planetary worms, are created in the surface of the above-mentioned toroidal gutter of the planetary worm, into which mesh the protruding halves of the tooth-balls of the satellite worm wheels. These spiral grooves are threads of the toroidal planetary worm. Number of groove spirals in a toroidal gutter of planetary worm can differ. The number is analogous to the number of starts of thread of a classic worm, where with the increasing number of thread starts of the worm, would reduce the level of self-locking of the worm gear. Each of these two toroidal planetary worms will be via own spiral grooves in a permanent contact with all satellite worm wheels, mounted in the slip adhering disc carrier of the satellite wheels.

The differential operates in a way that the driving torque from the input drive shaft via the input drive is transferred to the differential body flange, and by that also to satellite worm wheels carrier, rigidly connected to the differential body. As the satellite worm wheels have their rotation axes directed tangentially to a circle described by centres of their mountings in carrier, so the driving force from the satellite carrier will be proportionally distributed on carrying balls of the satellite wheels, in the direction of their rotation axis. Further, the proportional force per carrying ball of one satellite wheel will split among tooth-balls of the satellite wheel, in the relation of number of meshing tooth-balls with toroidal planetary worms, where also the forces acting on all meshing tooth-balls are parallel to the rotation axis of the satellite worm wheel.

The tooth-balls of the satellite wheels, standing out on one side of the carrier, mesh the grooves of one planetary worm, and the tooth-balls on opposite sides of diameters of satellite wheels, standing out on the opposite side of the satellite carrier, mesh grooves of the second planetary worm, thus transferring forces from the carrying ball of the satellite wheel to walls of spiral grooves. The spiral grooves in gutters of both toroidal planetary worms are mutually mirror symmetrical, according to the parting plane of carrier perpendicular to the axis of carrier rotation, so one toroidal planetary worm has right-handed spiral grooves, and the second toroidal planetary worm has left-handed spiral grooves.

Axes of the worm spiral grooves are inclined towards the rotation axis of the satellite wheel in places of given positions of tooth-balls in groove, always under the angle of pitch of the spiral groove of planetary worm, so forces transferred by tooth-balls of satellite worm wheels are in the inclined groove vectorially decomposed into two forces: one force acting as pressure of the tooth-ball perpendicularly on the groove wall, and the other force in the tangential direction to circle, on which centres of tooth-balls of the satellite wheel are located. This second force makes efforts to rotate the satellite wheel, but as on the other side of the carrier is identical mirror symmetrical situation with decomposition of driving forces on the opposite side of the diameter of the satellite worm wheel in groove of the second planetary worm, so similarly one of distributed forces of the tooth-ball also makes efforts to rotate the satellite wheel, but exactly in the opposite direction, and this means, with equivalence of these forces, the satellite worm wheel will stay without any rotation. As components of the forces making efforts to rotate the satellite wheel on both sides of the satellite wheel diameter compensate each other, so on both sides of the satellite wheels, only pressure forces of the tooth-balls on groove walls will be of use. Whereby groove spirals of the toroidal planetary worms are mirror symmetrical, pressures of tooth-balls on walls of the spiral grooves will cause equal torque on both toroidal planetary worms, and from them via half-axles to driving wheels. The above-described activity is typical for the vehicle movement in the straight direction, when both wheels of the car driving axle are rotating equally, and all differential components are inside the body without any mutual movement, this means that satellite wheels in carrier are not rotating around their axes, and so also the toroidal planetary worms are rotating synchronously with the differential body.

When worm gears, designed in specific differential structure as self-locking, mainly by the selection of the number of spirals on toroidal planetary worms, then the self-locking of worm gears between the satellite worm wheels and planetary worms, will preserve equal rotation of both wheels, also in cases of substantial reduction of adhesion conditions below one of the wheels.

Only when car axle wheels will drive in a bend, the wheel located on the outer side of the bend, compared to the wheel on the bend inner side, will start to rotate with higher speed on the longer route. From the position of imaginary observer on the body of rotating carrier disc, it will look like as wheels, and toroidal planetary worms, were rotating towards carrier disc in the opposite directions. And because of opposite threads of the spiral grooves on the planetary worms, such opposite rotation of the planetary worms will act from spiral grooves on the planetary worms via tooth-balls on the satellite worm wheels with identical torque, and therefore the satellite worm wheels will enable this opposite rotating of driving axle wheels. Enabling of such opposite rotation movement of the output shafts represents the essential and desired property of each differential. DESCRIPTION OF DRAWINGS

To understand the structure, the following pictures illustrate the invention description:

Fig. 1 - Schematic presentation of the invention principles via explanatory derivation from the classic open differential. Fig. 2 - Schematic presentation of the differential properties with toroidal worm.

Fig. 3 - View of the differential assembly in a full cut through the plane along the rotation axis.

Fig. 4 - Satellite worm wheels carrier with satellite wheels.

Fig. 5 - Toroidal planetary worms of the output shafts.

The first two pictures (Fig. 1 and Fig. 2), present explanatory schematic illustrations, which should facilitate the explanation of the invention principle. To distinguish numbering of the schematic positions from positions in the following invention technical drawings, the schematic illustrations have an independent numbering of positions of the individual components where position numbers are larger than 100 (one hundred).

The first picture Fig. 1, in the illustration indicated by the letter A, presents schematically the known classic assembly of the worm gear, this means worm wheel 101 and worm 102, whereby to increase the number of teeth of the worm wheel meshing the worm, the worm has a globoid shape of the thread 105. This concave globoid shape of the axis cross-section of the worm is maintained, copying the circular circumference of the worm wheel, also for the following worm transformations.

The illustration B presents the first transformation of the rotational worm 102 to the linearly sliding worm 103 in a bar shape with a rack thread. Profile of the bar 105 maintains the arched concave profile of the original globoid rotational worm, to adapt the bar to the worm wheel. The next illustration C presents the second worm transformation, where from the previous linear bar shape 103, the worm is transformed into a shape of a ring or disc 104, created by bar bending into a circle and joining its ends. With the concave crosscut 105, maintained on the thread part of the disc, to adapt to the circular circumference of the worm wheel 101, which from the mathematics point of view represents a part of the surface of the imaginary toroid, created by the circumference of the worm wheel 101, during movement against the worm ring - disc.

Following illustrations present transition from the classic open differential to the invention principle. The scheme D presents classic open differential, where from the input shaft 106, the input torque is transferred via bevel gear 107 to differential body 108, and via internal gears to the output shafts 109 and 110. In the differential body, an assembly of bevel toothed gears is installed, consisting of two satellite wheels 113, rotary mounted on shaft 114, connected to the differential body 108, whereby satellite wheels 113 mesh with two planetary wheels 111 and 112, this means with one planetary wheel 111 of the left output shaft 109, and with the other planetary wheel 112 of the right output shaft 110. This open differential is easy to produce, fully suitable for instance for car axle for usual operation, but with problems to transfer the necessary torque to one wheel, if the other wheel on the car axle has extremely low adhesion on the underlying terrain. Therefore, design engineers are looking for solutions how to protect the free rotating system of satellites 113 and planetary wheels 111 and 112 against undesired mutual rotations. The common feature of a substantial part of the existing solutions is the implementation of different combinations of worm gears into the gear chain, with using of their increased friction or eventually also of their self-locking.

The next illustration E presents a replacement of every previous bevel satellite wheel 113 by a system of the worm wheel 116, mounted to the differential body 108 by the console 120, and worms 115, whereby because of natural skew lines of axes of worm gears, it is also necessary to use other gears 117, from worms 115 to bevel toothed planetary wheels 111 and 112 of output shafts 109 and 110, for instance as presented in this scheme. It is also obvious from the schematic illustration, that by such adding of worm gears, the differential complexity will increase and for maintained similar outer dimensions of the entire differential, it would be necessary with the increasing number of gears, to deal with decreasing dimensions of individual gears, which would mean a differential with more demanding structure, materials, production, as well as operation.

The next illustration F presents an application of the submitted invention principle, which simplifies the number of necessary gears by using a worm transformed into a ring - disc shape (presented in the Scheme C, position 104). This picture presents the use of two-disc toroidal planetary worms 118 and 119, whereby one planetary worm 118 on the left output shaft 109 replaced two previous worms 115, two ancillary toothed- wheels 117, and the planetary bevel wheel 111, and equally on the right output shaft 110, one planetary worm 119 replaced two worms 115, two ancillary toothed- wheels 117, and the planetary bevel wheel 112. All that reduces the complexity of the internal differential gears structure and the number of components, and due to this fact (within the original total differential volume) individually used components could be larger and more robust, for sufficiently dimensioned transfer of necessary torques, for increased operational resilience and reliability. The illustration also indicates the S - S cross- section, described in the illustration G in the next picture.

Schematic explanations continue in the picture Fig. 2, presenting a more detailed description of the differential function with used toroidal planetary worms. The scheme G presents S - S plane cross-section (presented in the previous scheme F in Fig. 1), where we can see the front view of the toroidal planetary worm 118, with indicated shaded profile 125 of this worm 118, where on surface, close to periphery of the worm disc, the circular gutter with concave surface is visible, corresponding with the toroid cutting. In this scheme are also visible, from the axial view, the console carriers 120 of the satellite worm wheels 116, which rotationally fix their shafts to the differential body 108.

The next scheme H presents a differential which can have a different number of worm wheels 116, when necessary for different dedicated performance parameters, as well as for different spatial options of the mounting, with a different higher number of the satellite worm wheels 116 used. For instance, this scheme uses in total eight satellite worm wheels, with all simultaneously meshing the toroidal planetary worm 118 for the left half-axle, and naturally, all satellite wheels 116, also simultaneously meshing the second toroidal planetary worm 119 for the right half-axle (planetary worm 119 is not visible in this scheme).

The next illustration J presents how all individual carriers 120, of the satellite wheels 116, are in this invention integrated into one common satellite carrier in a disc shape 121, rigidly aggregated to the differential body 108. On the dotted circle 129, centres of the satellite wheels 116 are located, whereby their rotation axes are tangential to this circle 129. The full carrier disc 121 in this illustration completely hides a view on the toroidal planetary worm 118, only the satellite wheels 116 are visible, standing out of the passing through carrier holes to the side adhering second toroidal planetary worml 19, for the second half-axle 110.

Illustration K presents cross-section of the imaginary toroid 128, created by circumferences of the satellite wheels 116, located by their centres on the circle 129, during rotation of satellite carrier around its axis, identical with axes of output shafts, whereby the next illustration L presents the enlarged toroid cross-section 128, in place of the satellite wheel 116, also including the drawing of the satellite carrier 121, and adhering toroidal planetary worms 118 and 119 on both sides of the carrier 121. The satellite wheels 116, rotary mounted in the carrier 121, by their diameters exceed the thickness of the satellite carrier disc 121, to mesh both planetary worms 118 and 119, this means on one side of the carrier 121 with the worm 118 for the left wheel, and on the other side of the carrier 121 with the other worm 119 for the right wheel. In order that slip adhering planetary worms 118 and 119 could rotate against the carrier 121 for the satellite wheels 116, which are standing out outside of the side planes 130 and 131 of the carrier 121, so for the standing out parts 123 of the satellite wheels 116 are in the planetary worms designed round gutters with cross-sections 123, corresponding to side snips of the toroid 128 by the side planes 130 and 131 of the satellite carrier 121. The illustration M for clarification presents axonometric of one half of the toroid cut by side planes of the carrier 130 and 131 into three parts, of which the central part 121 represents in theory a part of the satellite carrier body. The two side parts 123 represent toroidal gutters, which are accurately in this shape dug out in the front surfaces of the planetary worms, to fit parts of the carrying balls of satellites standing out of side walls of satellite carrier. And the planetary worm could by slip touch the side wall of the satellite carrier, despite satellite bodies standing out. In planetary worms, in toroidal gutters 123 are created spiral grooves as threads of planetary worms (worm wheels teeth and planetary worm grooves in this scheme are not presented).

The illustration N presents transition from the schematic satellite worm wheel 116 to the realistic satellite worm wheel 122 of the invention. With regards to forces, which the satellite worm wheel must transmit in the direction of the rotation axis 127, and with regards to forces transmitted by tooth-balls 126 in tangential direction of the wheel 122 circumference, the body of the satellite wheel has a design of shape of a large carrying ball 122. For teeth of satellite wheels, which during their operation are alternatively meshing on one side the right-handed spiral grooves in one toroidal planetary worm 118, and later also left-handed spiral grooves in the second planetary worm 119, were tooth-balls 126 selected, by their half embedded in the satellite wheel body, with regular spacing on wheel circumference.

The last illustration P presents a schematic pie cut with a view of one uncovered satellite worm wheel 122, in designed realistic shape, mounted in the hole of the satellite carrier disc 121, rigidly connected to the differential body 108. Two toroidal planetary worms 118 and 119 are also visible in this cross-section. They have on their surface the toroidal gutter 123, adapted to standing out parts of carrying balls of the satellite wheels 122. In this toroidal gutter surface 123, the spiral worm grooves 124 are created, with a semicircle cut, they create the meshing for tooth- balls 126 of the satellite wheels 122.

After the schematic explanation of the invention principle in the following figures (Fig. 3, Fig. 4, and Fig. 5) will be described into details the technical solution of the invention.

Picture Fig. 3 presents complete cross-section by the plane passing through the rotation axis of the differential body. Feeding of the input torque to differential body is realised via the flange 2, with the input toothed wheel attached through holes 25 by screws (input toothed wheel and screws are not presented in the drawing).

The entire differential mechanics is encased in the differential body, created by the left cover 7, also with the component of the input flange 2, and the right cover 8, where between them is satellite worm wheels carrier inserted, consisting of two discs 9 and 10, mirrored symmetric according to the parting plane 1 of the carrier, perpendicular to the rotation axis. These four components 7, 8, 9, 10 have a common rotation axis 29, and screws 11 assemble them to the rotating differential body.

Two output shafts have rotation axes common with the rotation axis of the differential body 29, presented only as splining ends of the car half-axles 3 and 4 driving wheels of the driving vehicle axle. These half-axles are by splining mounted in the coaxial toroidal planetary worms 5 and 6, where the left half-axle 3 is mounted in the left planetary worm 5, and the right half-axle 4 in the right planetary worm 6. Both toroidal planetary worms 5 and 6 are rotary inside the differential body, and by the front planes 18 and 19, they slip touch the satellite worm wheels carrier 9 and 10.

The satellite worm wheels with shape of balls 12 with the tooth-balls 14 are mounted in the discs 9 and 10 of satellite carrier. This invention description uses eight satellite worm wheels 12, placed in the carrier holes with necessary spacing on a circle circumscribed by their centres, but their actual number in implemented realisation could differ, according to structural calculations based on performance parameters of the differential, mainly on transmitted output power and torque. These carrying balls of the satellite wheels 12 have on circumference of the rotation mounted the tooth-balls 14, which by one half are fit into the hemispheric beddings in the carrying ball of the satellite worm wheel 12, and by other half standing out to mesh the spiral grooves 15, created in surface of the toroidal gutter 13 of the planetary worms 5 and 6. Number of the tooth-balls 14 on one satellite worm wheel 12, used in this description is four, but a different design could contain a different number of tooth-balls, depending on calculation results, based mainly on transmitted power and torque.

The tooth-balls 14 during rotation of carrying ball of the satellite wheel 12 in carrier 9 and 10, alternatively mesh the spiral grooves 15 of the one or the other one toroidal planetary worms 5 and 6. When profile of the tooth-ball 14 during rotation of the satellite carrying ball of the satellite worm wheel 12 moves outside the surface area 18 of carrier 9 and 10, the tooth-ball 14 will start continuously to sink into one of the spiral grooves 15 of the toroidal planetary worm 5, and simultaneously a different tooth-ball 14, located symmetrically on the opposite end of diameter of the carrying ball of the satellite wheel 12, will move outside the second surface area 19 of the carrier 9 and 10, and continuously start to sink into one of the spiral grooves 15 of the second planetary worm 6. But the carrying balls 12 of the satellite worm wheels with the tooth- balls 14, will start to rotate around their tangential axes 23 in earner 9 and 10, only when planetary worms 5 and 6 are mutually rotating in the opposite directions, and that because of the fact that the spiral grooves 15, of the toroidal planetary worms have opposite sinuosity, this means that one toroidal planetary worm has right-handed grooves and the second one, mirrored symmetric planetary worm has left-handed grooves. Such relative rotation in the opposite direction of the planetary worms 5 and 6 against the differential body occurs when the car driving axle with this differential drives in a bend, and wheels on both axle sides are rotating with different number of rotations, and differential must distribute the torque from the input shaft to both half-axles of driving wheels.

The next picture Fig. 4 presents details of the satellite carrier 9 and 10, as well as of the satellite worm wheels 12. The satellite carrier consisting of two mirror symmetrical halves 9 and 10, is split by the plane of symmetry 1 , because of the reasons of simplifying the production options of the globoid beddings 27 for the carrying balls 12 of the satellites into carrier, production of the toroidal channels 22, for passing of the tooth-balls 14 through the carrier body, production of the globoid beddings 21 for the shaft-balls 20 of the carrying balls 12 of the satellite wheels, as well as for the reasons of productional assembly of the differential, and possibility to insert satellite wheels into carrier. In the top left are presented cross-sections of both symmetric halves of the carrier 9 and 10, with presented dotted circles, where the smaller one 16, represents the rotation circumference of the carrying ball of the satellite wheel 12, and the larger dotted circle 28 represents the rotation circumference of peaks of the tooth-balls 14.

In order that carrying ball of the satellite worm wheel 12 becomes rotary in the carrier 9 and 10, only around its tangential axis 23, it is in carrier fixed by two shaft-balls 20, which are by one half sunk in hemispheric beddings of the carrying ball 12, in places of passing of the rotation axis 23 through the surface of carrying ball 12, and by the second half, mounted in the hemispheric beddings 21, created in both halves of the carrier 9 and 10. Thus facilitating that the carrying balls 12 are slip rotary in their ball beddings 27, through which driving forces from carrier are transmitted, but have an option of rotation only around their tangential axis 23. During rotation of the satellite carrying ball 12, tooth-balls 14 pass free through the carrier body 9 and 10, via the designed channels 22. These channels 22, formed as toroidal, in order that the channel 22 would not limit the tooth-ball 14 during rotation of the carrying ball 12 in tangential movement and limit them only in radial direction, thus the tooth-ball 14 would not by centrifugal or gravity forces disengage from the hemispheric bedding in the carrying ball 12.

On the right side is presented the B - B cross-section of the satellite wheels carrier disc 9 (in the carrier symmetry plane), where the arrangement of holes for placement of satellite wheels is visible. Shaded area represents the parting plane 1 of the carrier (contact plane of two halves of the carrier 9 and 10). On the outer carrier circumference, holes 24 are located, for mounting screws 11, assembling covers 7 and 8 of the differential with discs 9 and 10 of the satellite carrier into one rotational differential body (details are visible on the position 11 of the Fig. 3). In the circle formation, eight created holes 26 are visible, where each dissected hole is bordered by globoid bedding areas 27 for the carrying ball 12 of the satellite wheel, globoid bedding areas 21 for mounting of shaft-balls 20, and channels with a toroidal shape 22, for passing of tooth-balls 14 through carrier body during rotation of the satellite wheel. In these created holes 26 are rotationally mounted carrying balls of the satellite wheels 12, with tooth-balls 14 and the shaft- balls 20.

The lower part of the figure presents satellite worm wheels in different views and cross-sections. It is obvious that the carrying ball 12 of the satellite worm wheel, has mounted on circumference in hemispheric beddings tooth-balls 14, and in places of transit of the rotation axis 23 through the surface of the carrying ball 12, in hemispheric beddings, two shaft-balls 20.

The last picture Fig. 5 on the left presents cross-section of the planetary worm 5 (cross-section E - E). Next to it, on the right side, at a distance equal to thickness of the satellite carrier (carrier 9 and 10 is not presented), with the cross-section F - F of the second mirror symmetrical planetary worm 6 presented. Between these planetary worms are dotted circles, indicating circumference of rotation of satellite worm wheels, where the smaller dotted circle 16 indicates the circumference of the unrepresented carrying ball 12 of the satellite wheel, and the larger dotted circle 28 indicates the circumference of rotation of the tooth-balls 14 peaks. In these cross- sections, the cross-sections of spiral groves 15 are also visible, created in the surface of the toroidal gutter 13 of planetary worm, where the grooves represent threads for the tooth-balls 14 of the satellite worm wheels 12.

The view (cross-section D - D) on the right-hand side presents the toroidal planetary worm 5, from the side of satellite worm wheels. The larger shaded area 18, close to worm circumference and around central hole with splining, represents a flat surface, by which the planetary worm 5 contacts in slip the surface of the satellite wheels carrier 9. The opposite shading differentiates surfaces of the toroidal gutter 13, in which carrying balls 12 of satellite wheels can move, standing out of the side plane 18 of the carrier 9. There is no shading on the spiral grooves 15, created in the surface of the toroidal gutter 13, in which the tooth-balls 14 of the satellite worm wheels 12 are moving.

Below the view of the planetary worm 5, is the view (cross-section H - H) of the second toroidal planetary worm 6, mirror symmetrical to the planetary worm 5, from the side of satellite worm wheels carrier. The larger shaded area 19, close to the worm circumference and around the central hole with splining, represents a plane surface, by which the planetary worm 6 contacts in slip the surface of the satellite wheels carrier 10. The opposite shading differentiates surfaces of the toroidal gutter 13, in which move the carrying balls 12 of satellite wheels, standing out of the side plane 19 of the carrierlO. There is no shading on the spiral grooves 15, created in the surface of the toroidal gutter 13, in which move the tooth-balls 14 of the satellite worm wheels 12.

The two above mentioned spiral grooves 15, created in the surface of the toroidal gutter 13, on each planetary worm 5 and 6, for an analogy with the classic worm, represent a thread solution with two starts, this means two threads. It is known from the worm gear theory that the number of worm threads has an impact not only on worm gear ratio, but simultaneously also on the level of the gear self-locking. With the increasing number of thread starts increases the angle of pitch of screw line of worm thread, thus reducing the gear self-locking.

Although the number of groove starts in the planetary worm toroidal surface could have different impact on gear self-locking unlike the same number of thread starts of classic globoid worm, so for specific designs of differential, according to specified vehicle performance parameters, it will also be possible to use solutions with different numbers of thread starts of toroidal planetary worms, this means a different number of spiral grooves in the worm toroidal gutter. List of reference signs in drawings of schematic illustrations (Fig. 1, Fig. 2):

101 - classic worm wheel

102 - classic globoid worm

103 - worm transformed into a bar with surface in the form of a gutter

104 - worm transformed into a disc with a toroidal gutter on surface

105 - concave profile of the gutter surface on the worm adjusted for the worm wheel

106 - input propeller shaft of a torque feed to the differential

107 - input drive gear from the input shaft to a differential body

108 - differential body

109 - left output shaft (half-axle of a left wheel on car axle)

110 - right output shaft (half-axle of a right wheel on car axle)

111 - planetary bevel gear of the left half-axle 112 - planetary bevel gear of the right half-axle 113 - satellite bevel gear

114 - carrying shaft of the satellite bevel gears

115 - complemented worm to achieve self-locking properties of the differential

116 - complemented worm wheel

117 - complemented drive from the planetary bevel gear of the half-axle to the complemented worm

118 - toroidal planetary worm of the left half-axle

119 - toroidal planetary worm of the right half-axle

120 - individual carrier of the satellite worm wheel

121 - common disc carrier of all satellite worm wheels

122 - carrying ball as the practical realisation of the satellite worm wheel

123 - space of the toroidal gutter implemented in the planetary worm

124 - spiral thread groove for engagement of tooth-balls from satellite worm wheels

125 - embedded shaded cross-section of the toroidal planetary worm

126 - tooth-balls of the satellite worm wheel

127 - rotation axis of the satellite worm wheel

128 - imaginary toroid created by satellite wheels during rotation of the satellite wheels carrier

129 - common circle of placing of satellite wheels centres

130 - left side plane of the satellite wheels carrier disc

131 - right side plane of the satellite wheels carrier disc List of reference signs in drawings of the technical solution (Fig. 3, Fig. 4, Fig. 5):

1 - parting plane of the satellite wheels carrier

2 - flange for the toothed wheel of the input drive

3 - output shaft of the left wheel (left half-axle of the car driving axle)

4 - output shaft of the right wheel (right half-axle of the car driving axle)

5 - left toroidal planetary worm (mounted on the left half-axle of the driving axle via splining)

6 - right toroidal planetary worm (mounted on the right half-axle of the driving axle via splining)

7 - left cover of the differential body

8 - right cover of the differential body

9 - left half of the split satellite wheels carrier

10 - right half of the split satellite wheels carrier

11 - screws for aggregation of the differential body with satellite wheels carrier

12 - satellite wheel carrying ball

13 - toroidal gutter in the planetary worm

14 - satellite wheel tooth-ball

15 - groove in the toroidal gutter for engagement of satellite wheels tooth-balls

16 - indicated circumference of the satellite wheel carrying ball not presented in the drawing

18 - contact plane of the left toroidal planetary worm with satellite wheels carrier

19 - contact plane of the right toroidal planetary worm with satellite wheels carrier

20 - shaft-ball of the rotational mounting of the satellite wheel in the satellite wheels carrier

21 - globoid bedding for the shaft-ball of the rotational mounting of the satellite wheel in the carrier

22 - passage for movement of tooth-balls of satellite wheels through the carrier body

23 - tangential rotation axis of the satellite wheel in carrier

24 - holes for mounting screws of the differential body and satellite wheels carrier

25 - holes for screws to mount toothed drive wheel of the input transmission to the flange

26 - holes with dissected surface in carrier for mounting of satellite wheels

27 - bedding with globoid surface for mounting of the carrying ball of the satellite wheels in carrier

28 - rotation circle of peaks of tooth-balls of satellite wheels

29 - common rotation axis of the differential body, carrier, toroidal planetary worms, and output half-axles. PRODUCTION METHOD

Present production capacities of machine industries dispose of all means (materials, machines, and technologies) necessary for production of the submitted invention. Invention applies to the automotive industry and could replace the present mass manufactured and used open differentials in driving systems of motor vehicles.

INDUSTRIAL APPLICABILITY

The described invention of the permanent differential with toroidal worms has the largest targeted use in road transportation, in passenger cars, in the function of car axles differentials in car driving axles, or also in the function of inter axle differentials in cars with more driving axles. But the invention is also suitable for freight transport vehicles or mass public transport. The invention can permanently satisfy own goal of wheel drive also in extreme adhesion conditions below different driving wheels and contribute to steering control and thus to higher driver comfort and safety of vehicle operation. With regards to productionally undemanding structure, the price can come close to the price of classic open differentials and replace them to a larger extent, already directly in serial production lines.