DE29702710U1 - Reduction gear - Google Patents

Description

HL193a

14.02.97

Applicant: Hirn, Helmut, Dipl.-Ing., 72147 Nehren Laudenbach, Franz,· 78559 Gosheim

Designation: Reduction gear

The invention relates to a reduction gear consisting of a non-rotatably fixed support body, with which a radially flexible rolling ring is engaged, which has a rolling toothing that has a different number of teeth than a counter toothing of the support body that engages with it through at least one section, whereby a relative rotary movement is generated between the rolling toothing and the counter toothing that engages with it in sections by the rolling movement of the rolling ring, and whereby the rolling toothing is held in engagement with the counter toothing in rotating alternation by an engagement holder that is rotatably mounted coaxially to the axis of the support body and driven in rotation by a drive shaft and eccentric to the axis of the support body, and whereby the rolling ring is in a rotationally fixed connection to a working shaft via a connecting member.

Gearboxes of this type are known in the professional world under the term "Harmonic Drive System" (Dubbel, Pocket Book for Mechanical Engineering, 15th edition, p. 1069/ company publication of Harmonie Drive System GmbH, 63225 Langen/Hessen).

These transmissions essentially consist of three basic elements, namely:

a) from the so-called wave generator as the actual drive element. This consists of an elliptical core part onto which a ball bearing is mounted and which is also provided with the drive shaft;

b) from the so-called Flexspline; this is a basically cylindrical but radially flexible steel bushing (rolling ring) with external teeth in which the elliptical core part is arranged so it can rotate and finally

c) from the so-called circular spline. This part is an internally toothed fixed support ring, the teeth of which are constantly in mesh with the elliptically deformable flex spline, i.e. with this deformable steel bush. The internally toothed support ring has a larger number of teeth than the flexible steel bush, which is constantly in mesh with two diametrically opposed circumferential sections with the internal toothing of the fixed

the support ring is in engagement. By rotating the elliptical core part in the flexible steel bushing, all the teeth of the steel bushing are brought into engagement with the teeth of the internal toothing of the fixed support ring one after the other with each revolution, which causes the steel bushing to rotate by the difference in the number of teeth.

With these gears, high gear ratios for slow speeds and reductions can be achieved with a very compact design. However, the input and output rotation directions are opposite. The formula for calculating the respective speed ratio between input speed and output speed is:

i ⁼

where Z ₁ is the number of teeth on the flexible steel bushing and Z ₂ is the number of teeth on the fixed, internally toothed support ring. According to the manufacturer of such Harmonie Drive gearboxes, gear ratios of 1:72 to 1:320 are possible.

Such gears are primarily used in special machines and industrial robots.

In a known embodiment of such a Harmonic Drive transmission (EP 0 514 829 A2), the radially flexible steel bushing is pot-shaped and is provided with a stable end wall at an axial distance from its external teeth. The thin, in its basic form cylindrical wall of the steel bushing is elastically deformable, so that it can adapt to the cylindrical shape of the end wall on the one hand and to the flexibly circumferential elliptical shape of the transmission core, i.e. the so-called wave generator, on the other.

In other embodiments of such gears, a second toothed ring with internal teeth is provided as a transmission element between the flexible steel bushing, i.e. the so-called flexspline, and an output shaft (EP 0 309 197 B2), which is arranged coaxially to the first, fixed, internally toothed support ring. This second toothed ring also has at least approximately the same inner diameter as the fixed support ring, but it has a different number of teeth than the fixed support ring. The teeth of the flexible steel bushing are simultaneously in engagement with the fixed support ring and with the rotating toothed ring, in such a way that the rotation of the flexible steel bushing is transmitted directly to the rotating toothed ring, in the ratio

1:1, because the rotating gear ring has the same number of teeth as the flexible steel bushing, which rolls in the gear ring of the fixed support ring during the rotation of the elliptical drive core.

In the following, the component corresponding to the steel bushing is referred to as the rolling ring.

Basically, the functionality of the generic reduction gear is based on the fact that circumferential surfaces of different lengths roll on each other without slippage, whereby the shorter circumferential surface rotates by the length difference when rolling, i.e. the shorter circumferential surface moves along the longer circumferential surface.

Since all of the individual parts of these known gears are made of steel or similar metal material and are generally equipped with radially elastic, i.e. deformable ball bearings, which are arranged between the outer surface of the elliptical drive core and the flexible rolling ring, these gears require very high manufacturing costs, especially since a high level of manufacturing precision is a prerequisite for perfect functioning. ■

A reduction gear is also already known (DE 296 14 738 Ul) which consists of a rigid support ring with an essentially cylindrical, possibly internally toothed support surface and a radially flexible rolling ring with an possibly toothed outer surface. The outer surface has a smaller circumferential length than the support surface. In this reduction gear, one or more circumferential sections of the outer surface are held in slip-free engagement with the support surface of the support ring by an elliptical drive core which is arranged rotatably within the rolling bush and driven in rotation by a drive shaft. The rolling bush is connected in a rotationally fixed manner to an output shaft via a connecting link.

However, this reduction gear differs from the so-called "Harmonie Drive" in particular in that the rolling bush is connected to an elliptical drive core by a large number of essentially radially extending, equally long transmission elements designed as spokes or tappets, the envelope circle of which has a significantly smaller diameter than the rolling ring, which is cylindrical in its basic form. In a

In a simple embodiment, the rolling ring is provided with the

Spokes formed transmission elements and a

The hub which rotatably encloses the drive core is designed as a one-piece injection-molded part.

Compared to the previously known and much older "Harmonie Drive", this reduction gear has many advantages, particularly in terms of being easier to manufacture and also because it is self-locking. However, the maximum achievable reduction ratios are essentially in the same order of magnitude as with the "Harmonie Drive". A certain minimum radial size cannot be undercut due to the existing spokes or tappets.

The invention is based on the object of designing a reduction gear of the type mentioned at the beginning in such a way that its few components are simpler and more cost-effective, can be manufactured in both large and small dimensions and can be easily assembled, in particular automatically, so that a higher degree of efficiency, a backlash-free engagement, significantly higher reductions or slow transmissions and a higher functional reliability can be achieved with the lowest possible friction losses. '' .

^ss s

This object is achieved according to the invention in that the rolling ring has at least one internal toothing which engages with a counter toothing designed as an external toothing with a different number of teeth and in that the transmission element consists of an engagement holder which rotates concentrically around the support body and the rolling ring and which acts radially on the outer surface of the rolling ring at least at one point in order to keep at least a section of its internal toothing in engagement with the counter toothing.

In the reduction gear designed in this way, the engagement holder takes over the function that the elliptical drive core performs in the "Harmonie Drive" and in the gear according to DE 296 14 738 Ul.

Compared to the known gears of the generic type, the design according to the invention not only creates a considerably more cost-effective manufacturing option, but also creates considerably greater variation options in the design and, in particular, enables a very small and compact design. The precision of the rotary motion transmission

can be achieved with much simpler means. With the design principle of the gear according to the invention, an engagement holder consisting of an elliptical hollow body can be used, but an elliptical drive core or an eccentric cam is not required.

The main advantage of the reduction gear according to the invention and the most important innovation, however, is that the rolling ring encloses the support body in the form of a central support wheel and is not arranged inside the support body, as in the known gears of the generic type. For this reason, there are much greater possibilities for variation with regard to the number of teeth on the support wheel on the one hand and the rolling ring on the other. The rolling ring can have a much larger number of teeth than the support wheel. The tooth shapes and engagement ratios between the support wheel and the rolling ring can also be optimized much more easily and better. "

While in the aforementioned known gears the rolling ring rotates in the opposite direction to the direction of rotation of the drive element, i.e. the elliptical drive core, in the reduction gear according to the invention the rotation

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Direction of the rolling ring is the same as that of the engagement holder which performs the role of the drive element.

However, the transmission according to the invention also has the further possibility of fixing or locking the rolling ring against its own rotational movements, so that only an output gear that is in engagement with its internal toothing is set in rotation when the rolling ring rolls on it.

Another significant advantage of the reduction gear designed according to claim 2 is that between an output gear of the rolling ring provided as a second internal gear and an output gear coaxial with the support wheel, similarly large reduction ratios can be provided as between the support wheel and the first internal gear of the rolling ring. Two reduction ratios of e.g. 50:1 and 51:1 can easily be provided, which are calculated according to the formula

¹ G = h~

111

a total reduction ratio of -= without having to noticeably increase the size.

- 11 -

The gear is self-locking in both directions of rotation, which means that no amount of torque (within the given load capacity) exerted on the rolling ring or the output gear in the drive direction or counteracting the drive is capable of turning the drive shaft or the engagement holder forwards or backwards. At the same time, this also means that the output shaft, which is in geared or direct connection with the rolling ring, assumes a precisely defined angular position when the gear or drive is stationary, which can only be changed by the drive, i.e. by a corresponding rotation of the drive shaft and the engagement holder in one direction or the other.

The well-known "Harmony Drive" does not have any self-locking function.

Due to its special design, the reduction gear according to the invention also makes it possible to make the power transmission between the drive shaft and the rolling ring variable in many different ways.

With the known gears of the type described above, the following must be observed with regard to the selection of the number of teeth of the rolling ring and the support ring: If two transmission elements are exactly diametrically opposed,

■ it is necessary that the difference in the number of teeth between the teeth of the support ring and the teeth of the rolling ring is two, four or six teeth. If three transmission elements are provided, a difference in the number of teeth of at least three teeth is required so that a perfect engagement between the teeth of the rolling ring and the teeth of the support ring can be achieved.

However, if you want to use a difference in the number of teeth between the number of teeth on the support ring on the one hand and the number of teeth on the rolling ring on the other hand that does not match the number of pressure elements arranged at equal angular intervals concentrically to the drive shaft, it is necessary to make an angular position correction of the pressure elements on the radial webs. If, for example, the rolling ring has only one tooth less than the support ring and if two diametrically opposed pressure elements of a two-armed radial web keep the rolling ring in mesh with the support ring at two points at the same time, then the bearing axis of one pressure element must have an angular distance from the bearing axis of the other pressure element that deviates by half a tooth pitch of 180°. The same applies to other differences in the number of teeth or a different number of pressure elements.

- 13 -

In the reduction gear according to the invention, this special feature only has to be taken into account if, for example according to claim 3, a casing body is provided as the engagement holder, which is intended to enclose the rolling ring completely tightly.

In the embodiments of the invention according to subclaims 4 to 14, these adjustments between the difference in the number of teeth and the number of pressure elements play no role, because the rolling ring can be freely adjusted on both sides of the respective engagement sections.

Particularly in the case of very small designs, it is advantageous to design the engagement holder according to claim 3. This design is also particularly suitable for transmitting large torques. In particular, in combination with a rolling bearing provided according to claim 5, it is able to transmit large torques. The functional principle of the reduction gear according to the invention can also be implemented with the designs according to claims 4 and 6, which represent approximately equivalent alternatives to the embodiment of claim 3.

However, these can only be used advantageously if the rolling ring has sufficient dimensional stability.

- 14 -

In the embodiment according to claim 3, the rolling ring is completely enclosed by the casing body and thus also guided over its entire circumferential length, so that it can still perfectly fulfill its task even with a somewhat weaker dimensional stability.

While it may be necessary to provide special sliding inserts to reduce sliding friction when using sliding shoes, the pressure rollers provided according to claim 6 have the advantage that they can roll on the outer surface of the rolling ring with little frictional resistance, so that no major frictional losses occur when they are used.

It is advisable to use such pressure rollers in a double or triple arrangement. If two pressure rollers are provided, an arrangement in a diametrical position is recommended. If arranged in threes, the pressure rollers should be mounted on corresponding radial webs at equal angular intervals of 120°.

The design of the invention makes it possible to adjust the tooth engagement(s) between the rolling ring and the support wheel or the output gear so precisely that a play-free tooth engagement is achieved without unacceptable or damaging friction or deformation losses.

- 15 -

:- 3.51-

While in the embodiment according to claim 8 the drive shaft is directly connected to the support wheel, with the embodiments according to claims 9 to 12 a gear ratio can be provided between the drive shaft and the engagement holder, which is included in the overall reduction. The use of "angle gears, via which the drive shaft is geared to the engagement holder, also opens up the possibility of arranging the drive shaft at right angles to the axis of the support wheel and the engagement holder mounted coaxially to it.

The configurations according to claims 13 and 14 ensure that the reduction gear according to the invention is a very important requirement for the existing tooth engagements, namely an exactly coaxial bearing between the engagement holder and the support wheel.

The design according to claim 15 provides the possibility already mentioned above of setting a first reduction ratio ii between the first internal toothing of the rolling ring and the fixed support wheel and ■

- 16 -

· t ·

between the second internal gearing of the rolling ring, a second reduction ratio i ₂ is provided, which leads to a very high overall reduction ratio. A particular advantage here is that the axial length of the gear is only increased insignificantly. With this design, it is also possible to build very small reduction gears of the generic type, the outside diameter of which is in the order of a few millimeters. It is expedient to manufacture the individual gear parts from plastic.

These high overall reduction ratios are based on the following functional principle:

The rolling ring, which is in engagement with the support wheel by its first internal toothing, rotates during one revolution of the engagement holder in the circumferential direction relative to the fixed support wheel by an amount which corresponds to the displacement.

Z -Z

ratio Z ₁ =—&zgr;, where Z ₂ is the number of teeth of the

first internal toothing of the rolling wheel and Z ₁ is the number of teeth of the support wheel.

The speed n ₂ of the rolling ring is given by

«·> =n _n \ — ,

- 17 -

where n ₀ is the input speed, ie the speed of the engagement holder.

While the first internal toothing with the number of teeth Z ₂ of the rolling ring rolls in the toothing of the stationary support wheel, the second internal toothing with the number of teeth Z ₄ of the rolling ring rolls simultaneously in the toothing of the output gear, which is arranged coaxially to the support wheel.

This rolling movement causes the output gear to rotate in the opposite direction by an angle that is determined by the ratio

Z-7

between the rolling ring and the output gear with the number of teeth Z _3. Accordingly, the speed n ₄ of the output gear is calculated according to the formula

(&ggr; _ 7 7 _ 7Y

&lgr; ₂ &zgr;,, z, ₄ &lgr; ₃

n n

From this it can be seen that the output gear comes to a standstill when the two reduction ratios i _x and i ₂ are equal, because in this case the output gear with the number of teeth n ₃ rotates backwards by exactly the angle by which the rolling ring rotates forwards. . ' ·

- 1!

This means that a resulting rotary movement of the output gear can only be achieved if the mentioned reduction ratios ii and i ₂ are unequal.

If the number of teeth Z ₄ is greater than Z ₂ with the same tooth number difference Z ₂ -Zi = Z ₄ -Z ₃ , then a negative value results for n ₄ , which means that the output gear rotates backwards.

The fact that the second internal toothing of the rolling ring, which functions as the output toothing, must have a larger number of teeth than the output gear, is a necessary result of the design principle.

In order to ensure trouble-free tooth engagement, it is expedient to provide one of the embodiments according to claim 1.6 or 17.

Instead of or in addition to a second internal toothing, the rolling ring can have an output toothing consisting of pin-shaped teeth according to claim 18, with which the output gear is in engagement.

- 19 -

The embodiment according to claim 19 can also be advantageous because it offers the possibility of arranging the output or working shaft at right angles to the system axis, i.e. to the common axis of the support wheel and the engagement holder.

While claims 20 and 21 relate to advantageous embodiments with regard to the shape and arrangement of the support wheel, the embodiment according to claim 21 provides a very simple, known form of the rolling ring.

When designing the rolling ring according to claim 15, depending on the size and magnitude of the torque to be transmitted, incorrect tooth engagements can occur between the teeth of the rolling ring on the one hand and the teeth of the support wheel or the output gear if the rolling ring is made of plastic and its toothing or teeth are subject to certain deformations in the engagement area.

By means of the embodiments according to claims 23 and 24, these problems can be solved in a simple manner and with a high degree of functional reliability.

With the ring rib provided according to these designs, it is possible to control the deformation of the individual teeth of the

- 20 -

both teeth of the rolling ring in the engagement area because this ring rib provides the teeth with a stabilizing connection in the circumferential direction and thus ensures correct tooth engagement on both sides of the ring rib.

This annular rib also makes it easier to provide a design according to claim 25, which also serves to increase the engagement security and achieve correct tooth engagement.

The embodiments according to claims 26 and 27 make it possible to provide a further reduction between the output gear and an output or working shaft.

In the design of the reduction gear according to the invention according to claim 28, a gear arranged in the manner of a sun gear within the rolling ring and engaging with its internal teeth becomes the output gear, which is driven by the rolling ring having a larger number of teeth against the direction of rotation of the

- 21 -

engagement holder is set in rotation. Here too, the output speed n _a is calculated according to the formula: -

7 -7

z, ₂ z,[

where Z ₁ is the number of teeth of the output gear and Z ₂ is the number of teeth of the internal teeth of the rolling ring.

A particular advantage of this variant is that the rolling ring can be in engagement with two or more output gears at the same time, which can be driven with different reduction ratios.

On the other hand, the embodiments according to claims 29 and/or 30 can also be advantageous in this context.

In an embodiment of the invention according to one of claims 1 to 14, claims 30 to 33 provide advantageous design options for the connecting member between the rolling ring and an output shaft, which enable an angle-accurate transmission of the rotary movements of the rolling ring to an output shaft with high radial flexibility and low friction loss due to deformation friction.

- 22 -

The design options according to claims 30 to 33 are only applicable if there is sufficient space available in the axial direction for such a connecting link. Where this is not the case, an embodiment of the invention according to claims 34 to 37 is more advantageous because these embodiments require significantly less space in the axial direction and also enable an exact, angularly accurate transmission of the rotary movement of the rolling ring to an output shaft.

However, due to the technical complexity of the shape of the coupling elements that are to be brought into engagement with one another, namely the coupling tongues on the one hand and the recesses that accommodate them on the other, the torque-transmitting connection between the rolling ring and an output shaft can only be achieved by an additional individual part, as is also the case with the embodiment that provides an output gear.

Further advantageous embodiments and refinements of the invention are the subject of claims 38 to 42.

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The invention is explained in more detail below using the drawing figures of several embodiments. It shows:

Fig. 1 shows a section through a reduction gear enclosed by a housing;

Fig. 2 shows a section S2-S2 from Fig. 1; Fig. 3 shows a section S3-S3 from Fig. 1;

Fig. 4 shows a reduced-size perspective front view of an enveloping body;

Fig. 5 shows another embodiment of the reduction gear in sectional view;

Fig. 6 is a section S6-S6 from Fig. 5; Fig. 7 is a section S7-S7 from Fig. 5;

Fig. 8 shows another embodiment of the reduction gear in sectional view;

Fig. 9 is a section S9-S9 from Fig. 8; Fig. 10 is a section SlO-SlO from Fig. 8;

Fig. 11 shows a greatly enlarged sectional view of a rolling ring equipped with two internal gears;

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Fig. 12 shows a section through another embodiment of the reduction gear;

Fig. 13 is a section S13-S13 from Fig. 12; Fig. 14 is a section S14-S14 from Fig. 12;

Fig. 15 is a sectional view corresponding to Fig. 13 without housing ring with a different engagement holder;

Fig. 16 is a sectional view of Fig. 12 corresponding to Fig. 14 without the housing ring with the engagement holder of Fig. 15;

Fig. 17 another embodiment of the reduction gear in sectional view;

Fig. 18 shows a section S18-S18 from Fig. 19;

Fig. 19 another embodiment of the reduction gear in sectional view;

Fig. 20 is a section S20-S20 from Fig. 19; Fig. 21 is a sectional view S21-S21 from Fig. 19;

Fig. 22 is a simplified sectional view S22-S22 from Fig. 12;

Fig. 23 shows a further embodiment of the reduction gear in sectional view;

- 25 -

Fig. 24 is a section S24-S24 from Fig. 23; Fig. 25 is a sectional view S25-S25 from Fig. 23;

Fig. 26 shows a sectional side view of an engagement holder with adjustable arms;

Fig. 27 is a view A27 from Fig. 26; Fig. 28 is a view A28 from Fig. 26; Fig. 29 is a section S29-S29 from Fig. 27; ■

Fig. 30 shows a further embodiment of the reduction gear in sectional view S30-S30 from Fig. 31;

Fig. 31 a section S31-S31 from Fig. 30;

Fig. 32 shows a further embodiment of the reduction gear in sectional view S32-S32 from Fig. 33;

Fig. 33 is a section S33-S33 from Fig. 32; Fig. 34 is a sectional view S34-S34 from Fig. 32;

Fig. 35 an embodiment of the reduction gear in which the rolling ring is provided with a flexible output bush;

- 26 -

Fig. 36 the output bushing from Fig. 35 as a single part in section;

Fig. 36a another embodiment of the output bush in section;

Fig. 37 shows a section through another reduction gear in which the rolling ring is connected at the front with integrally formed coupling tongues to a disk-shaped coupling body;

Fig. 38 shows a front view of the coupling ring from Fig. 37 as a single part;

Fig. 39 is a section S39-S39 from Fig. 38; Fig. 40 is a section S40-S40 from Fig. 39; Fig. 41 is a section S41-S41 from Fig. 39;

Fig. 42 the coupling body in front view A 42 from Fig. 43;

Fig. 43 is a section S43-S43 of Fig. 42;

Fig. 44 the front view of the coupling body from Fig. 42 with the inserted coupling tongues of the rolling ring from Fig. 38;

Fig. 45 another embodiment of the coupling body in front view;

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Fig. 46 is a section S46-S46 from Fig. 45;

Fig. 47 the front view of the coupling body from Fig. 45 with the inserted coupling tongues of the rolling ring from Fig. 38.

Fig. 48 shows a further embodiment of the reduction gear in section;

Fig. 49 is a section S49-S49 from Fig. 48; Fig. 50 is a section S50-S50 from Fig. 48; Fig. 51 is a section S51-S51 from Fig. 48.

Fig. 52 another embodiment of the reduction gear in section;

Fig. 53 a section S53-S53 from Fig. 52

Fig. 54 another embodiment of the reduction gear in section;

Fig. 55 a section S55-S55 from Fig. 54; Fig. 56 a section S56-S56 from Fig. 54; Fig. 57 a section S57-S57 from Fig. 54 without housing;

Fig. 58 is a section S58-S58 of Fig. 54 without housing and with a different engagement holder;

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Fig. 59 the upper half of the engagement holder with the rolling ring from Fig. 54 in an enlarged sectional view;

Fig. 60 another rolling ring and a matching tensioning wheel in section;

Fig. 61 a variant of the embodiment of Fig. 54 in section and

Fig. 62 a section S62-S62 from Fig. 61.

Based on the drawing figures described above, various embodiments of a reduction gear are described below, the basic components of which each form a support wheel 1 with an external toothing 2, a radially elastic rolling ring 5 with at least one internal toothing 6, an engagement holder 10 and an output gear 20 or another output element. At least the rolling ring 5 is preferably made of plastic. It can be designed as a toothed belt. Depending on the size, it is also possible to manufacture it from a spring-elastic metal, e.g. spring steel.

- 29 -

In the embodiment of Fig. 1 to 11, the rolling ring 5 is made of plastic. It has a first internal toothing 6 and next to it a second internal toothing 7, which are each formed as one piece. These two internal toothings 6 and 7 are separated from each other by a radial annular rib 54 (Fig. 11), which is integrally connected to all adjacent teeth on both sides of these two internal toothings 6 and 7.

However, this ring rib 54 not only separates the two internal teeth 6 and 7 of the rolling ring, but also stabilizes them, so that they are exposed to a much lower risk of deformation, especially in the critical limit area. The teeth connected to the ring rib 54 are given effective support, particularly in the circumferential direction, in which the critical deformation forces are effective.

By means of this annular rib 54, which should have at least the thickness of half a tooth pitch and which should extend radially at least from the root circle of the toothing with the largest diameter to the tip circle of the toothing with the smallest tip circle diameter, it is possible to give the two internal toothings 6 and 7 additional stability against twisting and deformation.

- 30 -

It is therefore possible to provide the two internal gears 6 and 7 with different numbers of teeth as well as with different tooth shapes and thus to create optimal engagement conditions in each case.

The first internal toothing 6, which performs the function of a drive toothing, is held in engagement with the external toothing 2 of the centrally arranged cylindrical support wheel 1 by the engagement holder 10 at two diametrically opposite sections, while a second internal toothing 7, which functions as an output toothing, is in engagement with the cylindrical external toothing 3 of the output wheel 20 at the same diametrically opposite sections of the rolling ring 5. _ .

These tooth engagements are created by the engagement holder 10 already mentioned, which in the embodiment of Figs. 1 to 14 has an elliptical cage ring 11 or at least one with an elliptical inner surface 12. This cage ring 11 completely encloses the outer surface of the rolling ring 5, i.e. both over the entire circumferential length and over the entire axial width. The elliptical shape of its inner surface 12 results in the sectional views of Figs. 2 and 3, 6 and 7 as well as 9 and 10, 13, 14,

—31—

and 16, shown section-wise engagement position between the internal gears 6 and 7 on the one hand and the support wheel 1 or the output wheel 20 on the other hand.

In all embodiments, the internal toothing 6 has a greater number of teeth Z ₂ than the support wheel 1 with the number of teeth Zi. In an analogous manner, the second internal toothing 7 in each case has a greater number of teeth Z ₄ than the output gear 20 with the number of teeth Z ₃ .

In the embodiment of Fig. 1 to 3, the central support wheel 1 is integrally connected to an end wall 25 of a cylindrical housing 26. It is arranged concentrically to the cylindrical end wall 25 of the housing 26. Its axis 30 forms the common system axis, to which the output gear 20 is also mounted coaxially. The output gear 20 is provided with an output shaft 21, which is rotatably mounted in a central bearing bore 22 of the support wheel 1.

The engagement holder 10 is also mounted coaxially to the axis 30 of the support wheel 1 and the output gear 20, which in the embodiment of Fig. 1 to 14 is provided with a radial wall 15 connecting the cage ring 11 to a central drive shaft 14.

- 32 -

The engagement holder 10 is expediently provided with its
Drive shaft 14 by means of a rolling bearing 16 in a
second end wall 27 of the housing 26 by means of a bearing bush 28 so that it can also be driven at very high speeds. The preferably
The circular end wall 27 is concentrically screwed to a cylindrical ring wall 29 of the housing 26.

When the engagement holder 10 is driven at high speeds
it is advisable to place between the rolling ring
5 and the inner surface 12 of the cage ring 11 a radial
elastic roller bearing 18, which is expediently designed as a needle bearing and is at least approximately
extends over the entire axial width of the rolling ring 5.

In the embodiment of Fig. 5 to 7, the housing 26 is missing. In addition, the engagement holder 10 is provided with a
Hollow hub 14/1, which takes over the task of the drive shaft 14. The support wheel 1 with its external toothing 2 is part of a cylindrical bearing block 4, on
which a ring-shaped output gear 20/1 with its external teeth
3 is rotatably mounted. This output gear
20/1 is provided with a ring flange 22, which

- 33 -

can be connected to any gear part to be driven.

The bearing block 4 is provided with eccentric, axial fastening holes 9, which serve to accommodate fastening screws with which it can be fastened to a frame or housing part present on the application side. Here too, the rolling ring 5 with its two internal teeth 6 and 7, which are in engagement with the support wheel 1 and the output gear 21, is enclosed by the elliptical cage ring 11 of the engagement holder 10 with an inserted rolling bearing 18.

The embodiment of Fig. 8 to 10 differs in principle from the embodiment of Fig. 1 to 3 only in that the engagement holder 10 is provided with a hollow shaft 14/1 as in the embodiment of Fig. 5 to 7 and that an annular output gear 20/1 is also provided, which has a hollow shaft 21/1 as an output shaft. The support wheel 1 is formed in one piece on an end wall 27/1 of a housing 26, the cylindrical ring wall 29 of which is connected to this end wall 27/1 by screws 31. This ring wall 29 has a second end wall 25/1 in which a bearing bush 28 with a roller bearing 16 for the hollow shaft 14/1 or the engagement holder 10 is arranged.

- 34 -

The functionality of the described embodiments is as follows:

The support wheel 1 is stationary in any case. It is arranged so that it cannot rotate. The engagement holder 10 is usually driven by a motor at a high speed, so that the cage ring 11 rotates around the rolling ring 5, which is in engagement with the support wheel 1 with its first internal toothing 6. As a result, the teeth of the internal toothing 6 are brought into engagement one after the other with the teeth of the external toothing 2 of the support wheel 1, simultaneously in two sections that are diametrically opposite one another, as can easily be seen from the drawing.

The larger number of teeth Z ₂ of the internal toothing 6 results in a rotary movement of the rolling ring 5 relative to the fixed support wheel 1. The speed ratio between the rotating cage ring 11 of the engagement holder 10 and the rolling ring 5 is calculated according to the formula:

Where Z ₁ is the number of teeth of the support wheel 1, Z ₂ is the number of teeth of the first internal toothing 6 of the rolling ring 5,

- 35 -

n ₂ is the speed of the rolling ring 5 and n ₀ is the speed of the engagement holder 10 and the cage ring 11.

Assuming Z ₁ = 98 and Z ₂ = 100, this results in a

2
Speed ratio of Z ₁ = = 1:50. This means: after

Fifty revolutions of the engagement holder 10 mean that the rolling ring 5 just completes a full revolution.

Of course, depending on the size, higher reduction ratios are also possible, for example if Z ₁ = 198 and Z ₂ = 200, then the reduction ratio i _x = 1:100.

While the first internal toothing 6 of the rolling ring

5 rolls on the stationary support wheel 1, the same process also takes place between the second internal toothing 7 of the rolling ring 5 and the external toothing■3 of the output gear 20 or 20/1. However, while the rolling process between the first internal toothing

6 and the stationary support wheel 1 results in a rotary movement of the rolling ring 5 in the drive direction or the direction of rotation of the engagement holder 10, the rolling movement between the second internal toothing 7 and the driven gear results in a rotary movement of the driven gear. 20 or.

- 36 -

ml ***· "♦**· · r- -36 *—'

20/1 in the opposite direction. The rotational movement of the output gear 20, 20/1 relative to the rolling

_{Z4 -Z2}

ring 5 is calculated using the formula n ₄ = ti ₀ — , because

Z4

It is assumed that the rolling ring 5 is stationary, or because the output gear 20, 20/1 rotates relative to the rolling ring 5.

The resulting output speed n _g of the output shaft or the output gear 20, 20/1 is calculated using the formula

n ₂ -n ₄ = n _o \

7—7 7—7

£-"1 "1 4

7 Z

From this formula it can also be seen that the value in brackets becomes zero when both tooth number ratios or both reduction ratios are equal, which means that when the reduction ratios between the first internal toothing 6 of the rolling ring 5 and the support wheel 1 on the one hand and the second internal toothing 7 of the rolling ring 5 and the output gear 20 ■ or 20/1 on the other hand are equal, the output speed is zero, the output gear 20, 20/1 . is therefore stationary.

- 37 -

Furthermore, it can be seen from this formula that the output gear 20 or 20/1 then rotates in a direction opposite to the direction of rotation of the engagement holder 10 if the reduction between the rolling ring 5 and the support wheel 1 is smaller than the reduction between the rolling ring 5 and the output gear 20, 20/1.

It is also clear that very high reduction ratios can be achieved with this reduction gear with two tooth meshes. For example, a total reduction ratio of 1:2250 can be achieved from the two partial reduction ratios of 1:51 and 1:50.

Because the two tooth engagements 6/2 and 7/3 are located directly next to each other in the axial direction and also require approximately the same diameter, an extremely compact design is achieved.

Such a reduction gear can be built very cost-effectively in very small dimensions with diameters smaller than 10 mm if its components are made of plastic.

- 38 -

In principle, this also applies to the other embodiments, which are described in detail below.'

In the embodiment of Fig. 12 to 14, the engagement holder 10 is provided with a cage ring 11 which directly encloses a rolling ring 5/1, which therefore lacks the roller bearing 18. In addition, the engagement holder 10 is rotatably mounted on a bearing pin 35 of the support wheel 1 by means of a roller bearing 17 and is provided with a drive gear 37 which engages with a gear 38 of a drive shaft 14/2 which is mounted eccentrically to the axis 30 of the support wheel 1 by means of a roller bearing 19 in a bearing bush 40. The bearing bush 40 is fastened in an end wall 25/2 of a housing 26/2. This end wall 25/2 is screwed to an annular wall 29/2 which is provided with a second end wall 27/2 on the opposite side. In this second end wall 27/2, the output shaft 21 of an output gear 20 is rotatably mounted, which is centered in a central axial bore 24 of the support wheel 1 by means of a centering pin 23. The support wheel 1 is non-rotatably fixed in the end wall 25/2 by means of a square pin 31.

The output gear 20 is in engagement with its external teeth with pin-shaped teeth 48 of an output

- 39 -

toothing 47, which instead of a second internal toothing 7 engages the rolling ring 5/1 provided with only the first internal toothing 6. This output toothing 47 is arranged on the end face of the rolling ring 5/1 facing the output gear 20. The pin-shaped teeth 48 are designed as cylindrical pins in the embodiment shown. Other tooth shapes are also possible.

In Figs. 15 and 16 an embodiment is shown, which differs from that of Figs. 12 to 14 only in that an engagement holder 10/1 is provided which does not have a self-contained cage ring 11, but instead only has two diametrically opposed sliding shoes 50 and 51, which glide around the outer surface of the rolling ring 5/1 and are each arranged in one piece on a radial web 52 or 53, as if it were part of a cage ring 11.

In the embodiment of Fig. 17 and 18, the rolling ring 5/1 is held in engagement with the teeth of the support wheel 1 and the driven wheel 20 by an engagement holder 10/2, which is either provided with two sliding shoes 50

- 40 -

and 51 or with a cage ring 11, which in any case has a circular radial wall 15/1, on the outside of which there is a crown gear 55, the axially projecting teeth 56 of which engage with a pinion 57. The pinion 57 is part of a drive shaft 14/3, the axis 58 of which runs at right angles to the axis 30 of the support wheel 1. The crown gear 55 and the pinion 51 together form an angular gear 60. The drive shaft 14/3 is rotatably mounted in a bearing bush 59 in the annular wall 29/3 of a housing 26/3, which is closed at the front by two end walls 25/3 and 27/3. The bearing pin 35 of the support wheel 1 is non-rotatably fixed in the end wall 25/3 by means of a square pin 31. The engagement holder 10/2 is rotatably mounted on the bearing pin 35 by means of a rolling bearing 17.

In the opposite end wall 27/3, the output shaft 21 of the output gear 20 is rotatably mounted coaxially to the support wheel 1 and the engagement holder 10/2. Furthermore, the output gear 20, through its external toothing, is in engagement with the output toothing 47 of the rolling ring 5/1, consisting of pin-shaped teeth 48, in the same way as in the example in Fig. 12 to 16. The tooth engagements between the support wheel 1 and the rolling ring 5/1 are the same as shown in Fig. 13.

- 41 -

Fig. 19 to 22 show an embodiment of the reduction gear that differs from the embodiment of Fig. 12 to 14 or 15 and 16 only in a different form of the engagement holder. An engagement holder 10/3 is provided, which consists of a double-armed radial web with the arms 61 and 62 and which is attached in a rotationally fixed manner to a cylindrical projection 39 of the drive gear 37. The drive gear 37 is rotatably mounted by means of the roller bearing 17 on the cylindrical bearing pin 35 of the support wheel 1, namely coaxially to the axis 30.

The ends of the two arms 61 and 62 of the engagement holder 10/3 are each provided with bearing pins 64 and 65 running parallel to the axis 30, on which cylindrical pressure rollers 66 and 67 are rotatably mounted. As can be seen from Fig. 20 and 21, these two pressure rollers 66 and 67 or the bearing pins 64 and 65 supporting them are arranged diametrically opposite one another in relation to the support wheel 1, in such a way that the two pressure rollers 66 and 67 rest on the outer surface 13 of the rolling ring 5/1 in order to keep the inner toothing 6 of the rolling ring 5/1 in engagement with the outer toothing 2 of the support wheel 1 in the same way as the

- 42 -

in the embodiment of Fig. 15 and 16 the two sliding shoes 50 and 51 bring about this.

It is also possible to provide an engagement holder 10/3 with wider radial arms 61 and 62 and with two or more pressure rollers 66 and 67 each in order to make the engagement sections of the rolling ring 5/1 somewhat longer.

In Fig. 22, the two meshing gears 37 and 38 are shown in front view, which are also present in the same arrangement in the embodiment of Figs. 13 to 16.

The functionality of this embodiment of the reduction gear is the same as in the embodiment of Fig. 13 to 16. The reduction ratios between the rolling ring 5/1 and the support wheel 1 or the output wheel 20 correspond to the same principles as described above in connection with Fig. 1 to 16.

While in the embodiment of Fig. 17 and 18 an additional reduction between the drive shaft 14/3 and the engagement holder 10/3 by the angle gear

- 43 -

is present, an additional reduction can also be provided between the two gears 37 and 38, which is included in the overall reduction between the input shaft 14/2 and the output shaft 21.

In the embodiment shown in Figs. 23 to 25, the engagement holder 10/3 is directly connected to a drive shaft 14/3, which is rotatably mounted in an end wall 25/3 of a housing 26/3. The engagement holder 10/3 is attached in a rotationally fixed manner to an annular flange 42 of the drive shaft 14/3. The rolling ring 5/1 is held in engagement with the support wheel 1 by its internal toothing 6 in the same way as in the embodiment of Figs. 19 to 21. Instead of the driven gear 20, in this case a driven gear 20/2 is provided, which is in engagement with the pin-shaped end toothing 47 of the rolling ring 5/1. However, this output gear 20/2 is provided with an additional gear 72, which is in engagement with a gear 71. The gear 71 is fixedly mounted on a drive shaft 21/1, which is rotatably mounted in a bearing bush 70 of the second end wall 27/3 of the housing 26/3 in a position parallel to the axis 30.

Here too, it is possible to install an additional support between the output gear 20/2 and the output shaft 21/1.

- 44 -

Settlement must be provided which is included in the overall reduction. As with the housing 26/2, the two end walls 25/3 and 27/3 are screwed to an annular wall 29/2.

The output gear 20/2 is rotatably mounted on a bearing pin 35/1 of the support wheel 1. The bearing pin 35/1 is fixed non-rotatably in the front wall 27/3 by means of a square pin 31/1. In addition, the support wheel 1 is provided with a central centering pin 23/1 on the front side opposite the bearing pin 35/1, which protrudes into a coaxial centering hole 24/1 of the drive shaft 14/3.

Since it is often important in reduction gears of the type according to the invention to obtain a backlash-free but at the same time smooth tooth engagement between the support wheel 1 or the output gear 20, 20/1 on the one hand and the rolling ring 5, 5/1, 5/2 on the other hand, it is advantageous if, for example, the pressure rollers 66, 67 or the sliding shoes 50, 51 can be adjusted in the radial direction on the arms 61, 62 or on the radial webs 52, 53. Such optimal engagement conditions cannot always be achieved with the normal manufacturing tolerances.

For this reason, the embodiment shown in Figs. 26 to 29 provides an engagement holder 10/4,

- 45 -

in which the two pressure rollers 66 and 67 are mounted on bearing pins 64, 65, which are each attached to a radially adjustable actuating arm 68 or 69. These actuating arms 68, 69 are each radially adjustable in lateral guide rails 73, 74 of two radial arms 61' and 62' that are firmly seated on the ring flange 42 of the drive shaft 14/3 and are otherwise guided with as little play as possible and are each fixed by means of a clamping screw 77. These clamping screws 77 each extend through a radially aligned slot 63 and are screwed into a threaded hole 52 of an actuating arm 68 or 69.

The sliding shoes 50, 51 can also be made radially adjustable in the same or a similar way. If necessary, adjusting screws can also be provided for the precise adjustment of the pressure rollers 66, 67 or the sliding shoes 50, 51.

In the embodiment shown in Figs. 30 and 31, the same support wheel 1, the same rolling ring 5/1 and the same output gear 20 are provided as in the embodiment of Figs. 19 to 21. The two-armed engagement holder 10/3 with the two pressure rollers 66 and 67 and the bearing pins 64 and 65 are also present in the same way. In contrast to the embodiment of Figs. 19 to 21, the two-armed engagement holder 10/3 is

However, the handle holder 10/3 is attached to the hub 39/2 of a worm gear 37/2, which is rotatably mounted on the bearing pin 35. Here too, the bearing pin 35, which is integrally connected to the support wheel 1, is non-rotatably fixed by a square pin 31 in an end wall 25/3 of a housing 26/4.

A worm 38/2 is in engagement with the worm wheel 37/2. This worm 38/2 is mounted in two cheek-like wall parts 75 and 76 of a housing ring wall 29/4 and is provided with a coupling pin 77 protruding laterally from this housing ring wall 29/4, to which a motor drive can be coupled.

Otherwise, the support wheel 1 and the output gear as well as the rolling ring 5/1 are present in the same way as in the embodiment of Fig. 19 to 21. The mode of operation is also basically the same. However, in this embodiment of Fig. 30 and 31 it is possible to provide an additional reduction between a drive shaft and the engagement holder 10/3 by means of the worm gear 37/2 and 38/2, which is also an angle gear, which is included in the overall reduction.

- 47 -

»■■·

• . . i r- 4T·-

·

The embodiment of the reduction gear shown in Fig. 32 to 34 differs from that of Fig. 23 to 25 in principle only in that a rolling ring 5/2 with an internal toothing 6 is provided, which, however, instead of a second internal toothing 7 or a pin-shaped toothing 47, has a crown toothing 78 which consists of a gear ring with teeth 79 projecting on the front side in the axial direction. This crown toothing 78 is in engagement with a pinion 80 of an output shaft 21/3 extending radially, i.e. at right angles to the axis 30 of the support wheel 1.

The pinion 80 and the crown gearing 78 form an angular gear 60/1, which has an additional reduction ratio in addition to the reduction ratio existing between the internal gearing 6 of the rolling ring 5/2 and the support wheel 1, which is also included in the overall reduction ratio between the drive shaft 14/3 and the output shaft 21/3.

In the embodiments of Fig. 17 and 18 or 12 to 21 or 30 and 31 or 23 and 24 or 32 to 34, in which between a drive shaft 14/3 and the engagement holder 10 or between a drive shaft 14/2 and the

- 48 -

If there are additional gear reductions between the drive shaft 14/2 and the engagement holder 10 or between a coupling pin 77 and the engagement holder 10, these reduction ratios are each included as a multiplier in the overall gear ratio. If these gear ratios are each referred to as i _e , the resulting overall gear ratio is i _g = (I ₁ - i ₂ ) xi _e .

If, however, in the embodiment of Fig. 23 to 25, the output ratio i _a between the gear 72 and the gear 71 is included in the total reduction, the corresponding formula is:

ig = (ii - i ₂ ) x ia

In the embodiment of Fig. 32 to 34, in which the rolling ring 5/2 is in engagement with a pinion 80 of the output shaft 21/3 through a crown gear toothing 78, and in which a reduction ratio i _a exists between the crown gear toothing 78 and the pinion 80, the total reduction is calculated according to the formula:

i _g = ii χ i _a

- 49 -

&psgr; www« ■■» » w _&Lgr; -y^ —

In Fig. 35 to 36a on the one hand and Fig. 37 to 47 inclusive on the other hand, two different possibilities are shown of providing the rolling ring 5 in its various variants with an output shaft or a coupling part for an output shaft via connecting links which are either integrally connected to it or can be connected to it in a form-fitting manner, in which the tooth engagement of an output ring is also eliminated.

In the embodiment of the reduction gear according to Fig. 35 and 36, a rolling ring 5/4 is provided which, like the other rolling rings 5, has an internal toothing 6. This internal toothing 6 is in engagement with an equally wide external toothing 2 of the support wheel 1 in the presence of two sliding shoes 50, 51 of the engagement holder 10/1 on two opposite circumferential sections. As a connecting link to an output shaft, the rolling ring 5/4 has a relatively thin-walled output part 175 designed as an axial extension leading out of the housing 26/2, which has the shape of a partly cylindrical and partially conical hollow body. -

- 50 -

This output part 175 consists of a cylindrical wall section 176 which is directly connected to the toothed rolling ring 5/4 in one piece, to which a conical wall section 177 is connected, which is provided with a coupling hub 178 or with a shaft stub 179 (Fig. 27) for the connection of an output or working shaft.

As shown in Figs. 35 and 36, the conical wall section 177 tapers in the axial direction with increasing distance from the rolling ring 5/4 with a cone angle α of approximately 60°. It is important that this driven part 175 is provided in its area lying outside an axial retaining ring ⁵¹ with continuous longitudinal slots 180 which are evenly distributed in the circumferential direction and which extend in the axial direction over most of the conical section 177 and also into the cylindrical section 176. These longitudinal slots 180 should be very narrow and only serve to increase the radial flexibility of the driven part 175 so that the rolling ring 5/4 can deform into an elliptical shape without great resistance during operation, i.e. during the rotation of the engagement holder 10 driven by the drive shaft 14/2 via the gears 38/37. Twisting in the circumferential direction should be avoided if possible.

- 51 -

•&phgr;&phgr;&phgr;&phgr; · φ— ©1 ϕ — ·

φ φ φ · φφφφφ

&phgr;&phgr;&phgr;&phgr;&phgr;&phgr;&phgr; φ·· ·

ϕ ϕ ϕ · ϕ · ·

&phgr;&phgr;&phgr;&phgr; ·φ &phgr;&phgr; · ϕ · ·. ·

As can be readily seen, the structure of this embodiment according to Fig. 26 corresponds to Fig. 19, apart from the differently designed rolling ring 5/4 and the absence of a driven gear 20.

Fig. 36a shows another embodiment of the driven part 175. In this embodiment, the driven part 175' has the shape of an ogive-like hollow body 182, with longitudinal slots 180 also being provided in the wall, which give the ogive-shaped hollow body 182 the required radial elasticity or flexibility.

As in the embodiment according to Fig. 36, a coaxial shaft stub 179 is connected to the ogive-shaped hollow body 182.

Both the output part 175 according to Fig. 35 and 36 and the output part 175' according to Fig. 36a are each connected in one piece from plastic to the rolling ring 5/4.

- 52 -

Another possibility of transmitting the rotary movement of the rolling ring 5 to an output shaft or an output shaft 21/1 arranged eccentrically to the drive shaft 14/3 is shown in Fig. 37 to 47 inclusive. According to Fig. 37, a support wheel 1 is used which, as in Fig. 23 and 35, has a bearing pin 35/1 fixed non-rotatably in an end wall 27/3. A larger-diameter output part 85 is rotatably mounted on this bearing pin 35/1, which is in engagement with the gear 21/1 of the output shaft 21/2 mounted in the bearing bush 70 via a gear 72.

This essentially disk-shaped output part 85 is provided with a central bearing bore 86 which accommodates the bearing pin 35/1. The output part 85 is rotatable relative to the support wheel 1. It is in positive engagement with a rolling ring 5/5, the internal toothing 6 of which, as in the other embodiments, is held in section engagement with the support wheel 1 by two diametrically opposed pressure rollers 66 and 67 of an engagement holder 10/3.

- 53 -

As radially elastic coupling elements, which positively connect the rolling ring 5/5 with the output part 85 in the circumferential direction, the rolling ring 5/5 has several coupling elements - in the embodiment there are eight - evenly distributed in the circumferential direction

91. These consist of two coupling tongues

92 and 93, which each extend from a narrow axial web 94 the same distance to both sides in the circumferential direction. As can be clearly seen from Fig. 38 and 40, these coupling tongues 92 and 93 in the basic form of the rolling ring 5/5 lie on a circle 96 which is concentric with the internal toothing 6 or with the rolling ring 5/5 which is circular in this basic form, but which has a diameter D _k ' which is larger than the diameter D of its outer surface 13.

For the positive, play-free, and radially elastic or flexible reception of the coupling tongues 92 and 93, the output part 85 is provided with a corresponding number of, for example, eight recesses 97. These recesses have two axial grooves 102 and 103, which are also located opposite each other in pairs in the circumferential direction on a circle 96 with the diameter D _k and whose angular distance β corresponds exactly to the angle β that the two end edges

- 54 -

two coupling tongues 92/93 formed on the same axial web 94.

These axial grooves 102 and 103 are each widened by wall surfaces 105 and 106 or 107 and 108 that widen inward and outward in an arc shape, so that the coupling tongues 92 and 93 can bend radially elastically during the elliptical deformation of the rolling ring 5/5 in the rigid disk-shaped body of the output part 85, in order to offer as little resistance as possible to the deformation of the rolling ring 5/5.

In the embodiment of the driven part 85 according to Fig. 37, 42 and 43, the recesses 97 extend only over a part of the axial thickness of the disk-shaped body and they are surrounded by a thin annular wall 104.

However, Fig. 45, 46 and 47 also show an embodiment in the form of the driven part 85/1, in which the recesses 97 each completely penetrate the somewhat smaller width of the disk-shaped driven part 85/1, i.e. are open on both front sides, and in which the outer ring wall 104 is also missing. The recesses 97 are in this embodiment

- 55 -

form, i.e. open on the outside in the radial direction. Otherwise, the output part 85/1 is no different from the ■ · output part 85.

In Fig. 44 and 47, a sectional view is shown of how the coupling elements 91 with their coupling tongues 92 and 93 engage in a form-fitting manner in the recesses 97 of the output part 85 or 85/1. It can be seen that, viewed in the circumferential direction, there is a play-free connection between the eight coupling elements 91 and the output part 85 or 85/1 and that, due to the elasticity of the coupling tongues 102 and 103 and the radial depth of the recesses 97, the axial webs 94 have the possibility of carrying out a movement both radially inwards and radially outwards, which corresponds to the elliptical deformation of the rolling ring 5/5.

These embodiments shown in Figs. 37 to 47 of a connecting link between a rolling ring 5/5 and an output shaft 21/1 have the advantage over the connecting links in Figs. 35 to 36a that they take up significantly less space in the axial direction and can have greater stability in the circumferential direction with at least the same radial flexibility.

- 56 -

The embodiment of the reduction gear according to the invention shown in Figs. 48 to 51 has a similar structure to the embodiment of Figs. 1 to 3. However, a drive shaft 14/5 is provided which is integrally connected to an engagement holder 10/6 consisting of two radial arms 61 and 62, on which, as in the embodiment of Figs. 2, 3 and 24, pressure rollers 66 and 67 are rotatably mounted on bearing pins 64 and 65.

These pressure rollers 66 and 67 simultaneously keep two internal gears 6 and 7 of a rolling ring 5/6 engaged with a first driven gear 20 on the one hand and with a second driven gear 20/2 on the other hand during their rotation. In addition, this rolling ring 5/6 has a gearing 47/1 consisting of pin-shaped teeth 48 on its end face opposite the engagement holder 10/6, which is engaged with a support wheel 1/6 that is fixed and integrally connected to the end wall 25/4.

The special feature is that the toothing 47/1 has the same number of pin-shaped teeth 48 with the number of teeth Z ₂ as the fixed support wheel 1/6 with the number of teeth Z ₁ . This ensures that the rolling ring 5/6 is kept in contact with the

- 57 -

• ·· · — «D /· —

its two pressure rollers 66 and 67 do not rotate relative to the support wheel 1/6, i.e. since Z ₁ = Z ₂ , the reduction ratio X ₁ = 1:1 exists between the support wheel 1/6 and the toothing 47/1 of the rolling ring 5/6.

However, the two internal gears 6 and 7 of the rolling ring 5/6 each have a larger number of teeth Z ₄ and Z ₆ than the two output gears 20 and 20/2 with the number of teeth Z ₃ and Z ₅ , respectively, whereby a different reduction ratio exists between the output gear 20 and the internal gear 7.

_{Z6 -Z5}

Z ₃ =— can be chosen as between the internal

gear 6 and the second output gear 2/2, which is

from the formula i ₂ - —~.

As can be seen from Fig.48, the first output gear 20 is provided with a central output shaft 21, while the second output gear 20/2 is provided with a hollow output shaft 21/2 which is rotatably mounted on the output shaft 21.

This design simultaneously provides two different output speeds n _al and n _a2 at the same input speed n _o of the drive shaft 15/5, which are controlled by means of a rolling bearing.

- 58 -

gers 16 is rotatably mounted in a bearing bush 28 of the front wall 27/4.

The stationary mounting of the rolling ring 5/6 could also be achieved with other means, for example with a modified coupling part 85 and corresponding coupling tongues 92 and 93 attached to the rolling ring 5/6 as shown in Fig. 38 to 41, if the coupling part 85 is firmly connected to the housing or to another non-rotatable part.

It can be seen that with the design principle of Fig. 48, but also with the gear structure according to Fig. 1 with a rolling ring 5 or 5/6 having several internal toothings 6, 7, several output gears 20, 20/2 can be driven with different reduction ratios, so that from a predetermined input speed n _o of the engagement holder 10 or 10/6, several output speeds n _a i, n _a2 etc. can be obtained.

It is clear from this that the gear according to the invention can be used in a wide variety of ways and that with it, with two or three tooth engagements between

- 59 -

in the >· »

see a fixed support wheel 1, 1/1 and the rolling ring 5, 5/6 on the one hand and between one or more internal gears 6, 7 and one or more output gears 20, 20/1 very high reduction ratios can be achieved with minimal dimensions.

A very simple embodiment of the reduction gear according to the invention is shown in Figs. 52 and 53. The support wheel 1 is formed in one piece on an end wall 25/4 of a housing 26/4, which in addition to the end wall 25/4 also has an annular wall 29/2 and a further end wall 27/2.

The front wall 25/2 is provided with a central cylindrical bearing bore 22 in which an output shaft 21 of the output gear 20 is rotatably mounted. The external toothing 3 of the output gear 20 has a number of teeth Z ₃ which must differ from the number of teeth Z ₁ of the support wheel 1 by at least one tooth if the rolling ring 5 only has an internal toothing 6. A continuous internal toothing 6 extending over the entire width b of the rolling ring 5 is in engagement with these two external toothings 2 and 3 of the support wheel 1 and the output gear 20, the number of teeth Z ₂ of which must in any case be greater than the number of teeth Z ₁ of the support wheel 1. This number of teeth Z ₂ of the internal toothing 6 of the output

- 60 -

■ · · — i

rolling ring 5 could theoretically be the same size as the number of teeth Z ₃ of the output gear 20. However, because in practice the length of the rolling ring 5 must be greater than the circumferential length of the output gear 20, it cannot be avoided that the number of teeth Z ₁ of the internal toothing 6 of the rolling ring 5, which also meshes with the output gear 20, is greater than the number of teeth Z ₃ .

It must be ensured that, as shown in Fig. 53, the internal toothing 6 of the rolling ring 5 is not in engagement with the external toothing 2 or 3 of the output gear 20 or the support wheel 1 over the entire circumference.

As can best be seen from Fig. 53, the engagement holder 10/7 provided in this embodiment has a semicircular sliding shoe 50/1, which rests with its circular-arc-shaped inner surface 12 concentric with the axis 30 on the outer surface 13 of the rolling ring 5 and keeps it in engagement with the toothing 2 of the support wheel 1 on the one hand and the toothing 3 of the output gear 20 on the other hand via the pressure angle δ which is 180° in the illustrated embodiment. The sliding shoe 50/1 is made in one piece.

- 61 -

connected to an approximately circular radial wall 15/2, which is attached to a drive shaft 14/4.

The reduction ratios resulting from this embodiment are calculated using the formula

7-7 Z-7

Z-2 *-*\ ^2 ^3

z, z

For Zi = 50, Z ₂ = 54 and Z ₃ = 51, this results in a reduction ratio i _g = 1:54, which means that the output shaft 21 has rotated once through 360° after fifty-four revolutions of the input shaft 14/4.

As in some of the embodiments already described above, in this embodiment the drive shaft 14/4 is mounted in a bore 22' coaxially to the axis 30 of the output shaft 21 or the bore 22. The fact that the drive shaft 14/4 and the output shaft 21 can also be mounted using roller bearings does not require any special justification.

- 62 -

• « &Lgr;&PSgr; &psgr; ·····

It is also possible to use a rolling ring 5 that has two different internal teeth 6 and 7, as is the case in the embodiments of Figs. 1 to 9 or in the embodiment described below according to Figs. 54 to 59.

The wrap angle δ of the sliding shoe 50/1 should not be smaller than 90° in order not only to ensure a sufficiently large engagement section, but also to be able to provide the remaining part of the radially elastic rolling ring 5 made of plastic with sufficient guidance so that it maintains as consistent a shape as possible even at high speeds.

On the other hand, the wrap angle or pressure angle δ should not be greater than 270°. Ultimately, however, the optimal size of the pressure angle δ will have to be determined empirically or will depend on the respective operating conditions and design conditions, in particular on the selected number of teeth of the internal toothing 6 or 7 of the rolling ring and the number of teeth of the support wheel 1 and the rolling wheel 20.

The embodiment of Fig. 56 and 57 with the variants shown in Fig. 58 to 60 represent

- 63 -

len represent a modification of the embodiments according to Figs. 19 to 34.

In a closed housing 26/4, which in principle has the same structure as the housing 26/4 of the embodiment of Fig. 52 and 53, a support wheel 1 and an output gear 20 are arranged and mounted in the same way.

Instead of an engagement holder 10/7 with a single sliding shoe 50/1, however, an engagement holder 10/8 is provided which consists of two radial arms 61' and 62' to which bearing pins 64 and 65 are attached. Two separate, spur-toothed tension wheels 66/1, 66/2 or 67/1 and 67/2 are freely rotatably mounted on these bearing pins 64 and 65, which engage with the internal teeth 6 and 7 of the rolling ring 5 in such a way that they hold the rolling ring 5 in engagement with the teeth of the support wheel 1 and the output gear 20 at two diametrically opposed engagement sections E ₁ and E ₂ , each offset by 90°.

A significant difference to the embodiments of Fig. 19 to 34, in which the rolling ring 5/2 is held in engagement with the support wheel 1 by the pressure rollers 66 and 67 rotating around it, is only that

- 64 -

3 *

the rolling ring 5 must be considerably longer in this case because it is guided around the tension wheels 66/1 and 66/2 or 67/1 and 67/2. This means that the difference in the number of teeth between the teeth 6, 7 of the rolling ring 5 and the teeth 2 and 3 of the support wheel 1 or the output gear 20 must be considerably larger than is the case in the embodiments with the pressure rollers 66 and 67.

As Fig. 60 shows, it is also possible to provide a one-piece tensioning wheel 66' on the bearing pins 64 and 65 of the two radial arms 61' and 62' of the engagement holder 10/8 if the rolling ring 5 also has only a single continuous toothing 6, which is in engagement with both the support wheel 1 and the output gear 20.

However, if the rolling ring 5 has two different internal toothings 6 and 7, it is necessary to provide a separate tensioning wheel 66/1 and 66/2 or 67/1 and 67/2 for each of these toothings, because they are driven at different angular velocities.

As shown in Fig. 58, it is also possible to use the engagement holder 10/8, which supports the two radial arms 61' and 62'.

- 65 -

has to be additionally provided with sliding shoes 50 and 51, which are each attached to radial webs 52 and 53 running at right angles to the two arms 61' and 62', as is also the case in the embodiment of Fig. 15 and 16 (for reasons of space, the representations of Fig. 57 and 58 are each rotated by 90° compared to the representations 55 and 56).

In this embodiment, the total ratio between the drive shaft 14/4 and the output shaft 21 is also calculated using the formula

7-7 7-7

^s ~ 7 Z

where Z _x is the number of teeth of the support wheel 1, Z ₂ is the number of teeth of the internal toothing 6 of the rolling ring 5 which engages with it, Z ₃ is the number of teeth of the output gear 20 and Z ₄ is the number of teeth of the internal toothing 7 of the rolling ring 5 which engages with the output gear 20.

- 66 -

It can be seen from this that the total gear ratio results from the number of teeth Zi to Z ₄ of the meshing gears 2 and 6 or 3 and 7, and that the number of teeth Z ₂ and Z ₄ of the internal gears 6, 7 of the rolling ring 5 play a decisive role, because the latter are always considerably larger than the differences Zi-Z ₂ or Z ₄ -Z ₃ .

Finally, Figs. 61 and 62 show a variant of the embodiment of Figs. 54 to 57.

This variant has an engagement holder 10/9, which has a bearing pin 64 with the two tension wheels 66/1 and 66/2 on a radial arm 61', while the diametrically opposite radial arm 62' only has a balancing weight 65/1 for unbalance compensation.

Because in this embodiment the flexible rolling ring 5 made of plastic is only guided over the two tension wheels 66/1 and 66/2 and is in engagement with the external teeth 2 and 3 of the support wheel 1 and the output gear 20 with a wrap angle δδ of approximately 270°, the rolling ring 5 is in this case considerably shorter than in the embodiment of Figs. 54 to 57 and 58. For this reason, the two internal teeth

- 67 -

teeth 6 and 7 of the rolling ring 5 also have significantly smaller numbers of teeth.

Of course, it is also possible here to provide a rolling ring 5 with only a single continuous internal toothing 6, which simultaneously engages with the two external toothings 2 and 3 of the support wheel 1 and the output gear 20. In such a case, the two tensioning wheels 66/1 and 66/2 can also be replaced by a single tensioning wheel 66'.

The remaining structure of the embodiment shown in Fig. 61 and 62 corresponds to that of Fig. 54 to 57, whereby it should be mentioned that the engagement holder 10/9 in Fig. 62 has a different shape than the engagement holder 10/8, and could be designed in the same way as the engagement holder 10/8.

It should also be mentioned that in the embodiments of Fig. 52 to 62 inclusive, drives and output gears can be provided as in the embodiments of Fig. 12 to 34.

Claims (1)

14.02.97 Protection claims 1. Reduction gear,' consisting of a non-rotatably fixed support body (1) with which a radially flexible rolling ring (5) is in engagement, which has rolling teeth which have a different number of teeth than, ei ^; a counter toothing (2) of the support body (1) which is in engagement with it through at least one section, wherein a relative rotary movement is generated between the rolling toothing (6) and the counter toothing (2) which is in engagement with it in sections by the rolling movement of the rolling ring (5), and wherein the rolling toothing (6) is held in engagement with the counter toothing (2) in a rotating alternation by an engagement holder which is rotatably mounted coaxially to the axis (30) of the support body (1) and driven in rotation by a drive shaft (14) and is eccentric to the axis of the support body (1), and wherein the rolling ring (5) is in a rotationally fixed connection to a working shaft (30) via a connecting member (25), characterized in that
that the rolling ring (5) has at least one internal gear tion (6) which is in engagement with a counter toothing (2) designed as an external toothing with a different number of teeth, and that the transmission element consists of an engagement holder (10) which rotates concentrically around the support body (1) and the rolling ring (5) and which acts radially on the outer surface (13) of the rolling ring (5) at least at one point in order to keep at least a section of its internal toothing (6) in engagement with the counter toothing (2). 2. Reduction gear according to claim 1, characterized in that the support body consists of a support wheel (1) which is provided with an external toothing (2) forming the counter toothing and is designed and arranged in the manner of a sun gear of a planetary gear, with which the rolling ring (5) is in engagement by means of its internal toothing (6), this internal toothing (6) of the rolling ring (5) having a number of teeth (Z ₂ ) which is greater than the number of teeth (Z ₁ ) of the support wheel (1). 3. Reduction gear according to claim 1 or 2, characterized in that the engagement holder consists of a • · ·· «—or-» an enveloping body (11) provided with an elliptical inner surface, which encloses the outer surface of the rolling ring and which holds the inner toothing of the rolling ring (5) in engagement with the support wheel (1) with two diametrically opposed toothing sections (5a, 5b). 4. Reduction gear according to claim 3, characterized in that a radially flexible rolling bearing is arranged between the rolling ring (5) and the enveloping body. 5. Reduction gear according to one of claims 1 to 4, characterized in that the engagement holder consists of at least two sliding shoes arranged evenly distributed in the circumferential direction, which are attached to radial webs and keep the internal toothing of the rolling ring (5) in engagement with the support wheel (1) in sections. 6. Reduction gear according to claim 1 or 2, characterized characterized in that the engagement holder has at least one pressure roller which is mounted on a of the support wheel (1) parallel bearing pin of a radial web rotatably mounted coaxially to the support wheel (1). 7. Reduction gear according to claim 5 or 6, characterized in that the sliding shoes (50, 51) or the pressure roller(s) (66, 67) on the engagement holder (10/1, 10/2) are radially adjustable. 8. Reduction gear according to one of claims 1 to 7, characterized in that the engagement holder (10) is provided with a drive shaft (14) coaxial with the axis of the support wheel (1). Reduction gear according to one of claims 1 to 7, characterized in that the engagement holder (10) is provided with a gear (37) which is in engagement with a gear (38) of a drive shaft (14/2) arranged eccentrically to the axis of rotation (30) of the engagement holder. 10. Reduction gear according to one of claims 1 to 7, characterized in that the engagement holder (10/2) is in gear connection with the drive shaft via an angle gear (60, 38/2, 37/2). 11. Reduction gear according to claim 10, characterized in that the angle gear consists of a worm wheel (37/2) connected to the engagement holder (10/2) and of a worm (38/2) connectable to a drive shaft. 12. Reduction gear according to claim 10, characterized in that the angle gear (60) consists of a crown gear (55) fastened to the engagement holder (10/2) and a pinion (57) connected to the drive shaft (14/3). 13. Reduction gear according to one of claims 1 to ■ 12, characterized in that the engagement holder (10/2) is rotatably mounted on a concentric bearing pin (35) of the support wheel (1). 14. Reduction gear according to one of claims 1 to 12, characterized in that the engagement holder and the support wheel (1) are mutually centered by a centering pin (23) projecting into a centering bore (24). 15. Reduction gear according to one of claims 1 to 14, characterized in that the rolling ring (5) in addition to the first internal toothing (6) engaging with the support wheel (1) and acting as a drive toothing (7), has a separate output toothing designed as a second internal toothing (7) which is held in engagement by the engagement holder (10) with an output gear (20) in the same way and over the same sections of the rolling ring (5) as the first internal toothing (6) with the support wheel (1), the reduction ratio (ii) between the support wheel (1) and the rolling ring (.5) ^Z2 (;', =—— ) from the reduction ratio (i ₂ ) between 2 ~ 1 the rolling ring (5) and the output gear (Z ₂ =- — ) differs. _Z4 - _Z3 16. Reduction gear according to claim 15, characterized in that the output gear and the support wheel (1) are mutually centered in a coaxial position by a centering pin (23) projecting into a centering bore (24). 17. Reduction gear according to claim 16, characterized in that the output gear (20) is rotatably mounted on a central bearing pin (35) of the support wheel (1) coaxially thereto. 18. Reduction gear according to claim 17, characterized in that the output toothing (47) consists of pin-shaped teeth (48) formed integrally on the rolling ring (5). 19. Reduction gear according to one of claims 1 to 18, characterized in that the rolling ring (5/2) in addition to a drive toothing engaging with the support wheel (1) has a crown toothing (78) consisting of axially projecting teeth (79) on the front side, which is part of an angular gear (60/1) via which the rolling ring (5/2) is connected to a an output shaft (21/3) running transversely to the axis (30) of the support wheel (1) is in gear connection. 20. Reduction gear according to one of claims 1 to 19, characterized in that the support wheel (1), the rolling ring (5) and the output gear or the output pinion are enclosed by a housing. 21. Reduction gear according to claim 20, characterized in that the support wheel (1) is formed on an end wall of the housing. 22. Reduction gear according to one of claims 1 to 21, characterized in that the rolling ring (5)
consists of a plastic toothed belt that is inelastic in the direction of rotation. 23. Reduction gear according to claim 15, characterized in
that between the output gearing (7) and the drive gearing (6) there is arranged a continuously circumferential annular rib (110), which is len teeth of both gears (6, 7) are connected in one piece. 24. Reduction gear according to claim 23, characterized in that the annular rib (110) extends radially at least from the root circle of the input or output gear (6, 7) with the largest diameter to the tip circle of the gear (6, 7) with the smallest diameter. 25. Reduction gear according to one of claims 2 to 24, characterized in that the output toothing (7) of the rolling ring (5) has a different tooth shape and/or a different tooth pitch than its internal toothing (6) engaging with the support wheel (1). 26. Reduction gear according to claim 15, characterized in that the output gear (20/2) has a second coaxial gear (72) which is in gear connection with an output shaft (21/1) via at least one further gear (71). - 10 - 27. Reduction gear according to claim 15, characterized in that the output shaft is arranged eccentrically and parallel to the axis of the support wheel. 28. Reduction gear according to claim 1, characterized in that the rolling ring (5) is non-rotatably but radially deformably connected to a stationary support body or frame part and is in engagement with at least one central output gear (20) by at least one internal toothing, the internal toothing(s) (6) of the rolling ring (5) (each) having a number of teeth (Z ₂ ) which is greater than the number of teeth (Zi) of the output gear (20)(s). 29. Reduction gear according to claim 28, characterized in that the output shafts (21, 21/2) of several output gears are partly designed as hollow shafts and are mounted concentrically to one another. 30. Reduction gear according to one of claims 1 to 10, characterized in that the plastic rolling ring (5/4) serves as a connecting member to - 11 - · a working shaft has an output part (75, 75') which is designed as a hollow body and which extends axially out of the support ring (1). 31. Reduction gear according to claim 30, characterized in that the output part (175, 175') has a wall section with several narrow longitudinal slots (180) distributed in the circumferential direction. 32. Reduction gear according to claim 30 or 31, characterized in that a substantially cylindrical wall section of the output part (175, 175') is followed by a wall section (177 or 182) tapering outwards in a conical or ogive shape, which is provided with a shaft- or hub-like coupling part (178, 179). 33. Reduction gear according to claim 31 or 32, characterized in that the longitudinal slots (180) extend from the cylindrical wall section (176) into the conically or ogive-shaped tapering wall section (177). - 12 - 34. Reduction gear according to one of claims 1 to 10, characterized in that the rolling ring (5/5) made of plastic is provided on one end with several coupling tongues (92, 93) arranged at equal angular intervals, each of which extends from a narrow axial web (94) the same distance to both sides in the circumferential direction and for the positive reception of which a dimensionally stable output part (85, 85/1) is provided, which has open recesses (97) on the end face on a circular arc, into which the ends of the individual coupling tongues (92, 93) can be inserted in a suitable manner and in which the individual axial webs (94) of the rolling ring (5/4) can move radially. 35. Reduction gear according to claim 34, characterized in that the coupling tongues (92, 93) of the rolling ring (5/4) and the recesses (97) of the output part (85, 85/i) which receive them in a form-fitting manner each lie on a circular arc (96) whose diameter (D _k ) is larger than the outside diameter (D) of the rolling ring (5/4) which is circular in its basic shape. - 13 - &igr; ·· · &diams;·<&bull; · ·&mdash; f i · &mdash; 36. Reduction gear according to claim 34 or 35, characterized in that the output part (85, 85/1) has the shape of a disk with a central shaft journal (89). 37. Reduction gear according to one of claims 34 to 36, characterized in that the output part (85, 85/1) consists of plastic. 38. Reduction gear according to one of claims 1, 9 to 17 or 20 to 27, characterized in that the engagement holder (10/7) has a sliding shoe (50/1) fastened to a radial wall (15/2), which concentrically encloses the outer surface (13) of the rolling ring (5) which is in engagement with the support wheel (1) and an output gear (20) by its internal toothing (n) (6, .7) with a wrap angle (δ) which is approximately 90° to 270°. 39. Reduction gear consisting of a non-rotatably fixed support body (1) with which a radially flexible rolling ring (5) is engaged, which has a rolling toothing which has a different toothing a counter toothing (2) of the support body (1) which is in engagement with it through at least one section, whereby a relative rotary movement is generated between the rolling toothing (6) and the counter toothing (2) which is in engagement with it through the rolling movement of the rolling ring (5), and whereby the rolling toothing (6) is connected by a coaxial to the axis (30) of the support body (1) rotatably mounted and driven by a drive shaft (14), eccentric to the axis of the support body (1) is held in engagement with the counter toothing (2) in a rotating alternation, and wherein the rolling ring (5) is connected to a working shaft (30) in a rotationally fixed manner via a connecting member (25), characterized, that the rolling ring (5) has at least one internal toothing (6) which is connected to an external toothing (2) formed counter toothing (2) with different number of teeth (Z ₁ ) and that the engagement holder (10/8, 10/9) has at least one tensioning wheel (66 ¹ , 66/1, 66/2, 67/1, 67/2) rotating concentrically around the axis (30) of the support wheel (1), which is smaller than the support wheel (1) and which is mounted on a radial arm (61 ^? , 62') connected to a drive shaft (14/4) and by its - 15 - Engagement with the internal teeth (6, 7) of the rolling ring (5) keeps it in tensioned engagement with the support wheel (1) and a coaxial output gear (20) in sections. 40. Reduction gear according to claim 39, characterized in that the rolling ring (5) has two different internal toothings (6, 7) which are each guided over separate, coaxial tensioning wheels (66/1, 66/2, 67/1, 67/2) which are each in engagement with one of the internal toothings (6, 7). ----- 41. Reduction gear according to claim 39 or 40, characterized in that a counterweight (65/1) attached to a second radial arm (62') is assigned to the tensioning wheel (66') or tensioning wheels (66/1, 66/2, 67/1, 67/2) which are only present once in each case as an unbalance compensation. 42. Reduction gear according to claim 39 or 40, characterized in that the engagement holder (10/8) in addition to the diametrically opposed - 16 - : -s us radial arms (61 ¹ , 62 ') on which two diametrically opposed tensioning wheels (66 ¹ , 66/1, 66/2, 67/1, 67/2) are mounted, two sliding shoes (50/1, 51/1) which are offset by 90° from the tensioning wheels (66', 66/1, 66/2, 67/1, 67/2) and which enclose the outer surface (13) of the rolling ring (5) in the areas of the engagement sections (E ₁ , E ₂ ) between the support wheel (1) and the rolling ring (5).