EP1053408A1

EP1053408A1 - Machine element with hirth-type serrations

Info

Publication number: EP1053408A1
Application number: EP99908876A
Authority: EP
Inventors: Hans Betzler; Hans Lindenthal
Original assignee: Voith Turbo GmbH and Co KG
Current assignee: Voith Turbo GmbH and Co KG
Priority date: 1998-02-12
Filing date: 1999-02-11
Publication date: 2000-11-22
Also published as: WO1999041513A1

Abstract

The invention relates to a machine element with Hirth-type serrations, characterized in that individual serration elements are configured unsymmetrically.

Description

Hirth-toothed machine element

The invention relates to a Hirth-toothed machine element for positive connection with a second, complementarily toothed machine element.

Hirth gears have long been known as construction elements for a variety of different purposes. As a representative reference is made to the Voith company brochure G 749 9.92 1500. The basic idea of the Hirth gearing is to have all geometric lines one

Form spur toothing in a wedge shape and bring it together centrally at one point. A toothed ring, which runs in the circumferential direction and has teeth extending in the radial direction with respect to the central axis, is thus created on a machine element for the purpose of torque transmission. The design of two to be coupled together

Machine elements with complementary Hirth serrations enable the creation of a positive self-centering connection between them, the Hirth serrations being used as such as a space-saving part element with high partial accuracy or as a fixing element with high repeatability. The

Possible uses of such connecting elements are very versatile and are not restricted to specific examples of use. Use in general mechanical engineering is conceivable, for example when connecting high-speed compressors and turbine impellers to the rotor shaft, gear sets or crankshafts. A performance increase can be achieved with the same volume where conventional screw connections, eg. B. flanges, hubs and shafts have reached or exceeded the limit of transmission capacity. A gain in volume and mass can also be achieved with such a connection where the space is already very limited. The assembly designed very easy due to the centering effect, furthermore, components designed in this way are very easily interchangeable.

For realizing a torque transmission and compensation of the axial forces occurring due to the acting peripheral force

Connection of two machine elements with mutually complementary Hirth teeth is usually axially preloaded. For this purpose, means are used in addition to the form-fitting and self-centering connection, which enable axial bracing of the two machine elements to be coupled together. Axial bracing means the generation of bracing with at least one component in the direction parallel to the axis of rotation of the machine elements. Mainly screw connections and tie rods are used as a means. In addition to an additional weight gain, these also require an increased amount of installation space, which corresponds to this in advance

Use in the design of the connection must be taken into account.

The invention is therefore based on the object of further developing a positive connection by means of a Hirth toothing in such a way that the disadvantages mentioned are avoided, in particular that the increased

Minimum space and weight requirements can be met. The design effort is to be kept as low as possible.

The solution according to the invention is characterized by the features of claim 1. Advantageous configurations are given in the subclaims.

Accordingly, a Hirth toothing or a machine element provided with a Hirth toothing for transmitting torque to another is provided with a complementary Hirth toothing Machine element implemented by realizing a positive connection between the two such that at least one or at least individual toothing elements are asymmetrical, ie have an asymmetrical geometry with respect to the tooth profile. A Hirth toothing is understood to mean a toothing which is preferably used in rotating components and is designed such that the geometric lines of the front toothing are wedge-shaped and bring them together centrally at a point which is on the axis of symmetry or axis of rotation of the machine element is arranged. The gearing itself is one

Spline teeth, the individual flanks of which can essentially be described by means of one plane. The toothing itself is arranged in the circumferential direction of the rotating component. The individual toothing elements extend in the radial direction with respect to the axis of rotation, the flanks are each aligned in the circumferential direction. The

Tooth height differs in the radial direction from the axis of rotation, with regard to the height and dimensions of the individual toothing element and the dimension of the toothing. The toothing is designed inclined to the central center or to the axis of rotation.

The design of individual gear elements with asymmetrical

According to the choice of the direction of rotation, geometry offers the advantage that either

1. A part that can be compensated for the torque transmission due to the peripheral force from the positive and self-centering connection of the Hirth toothing, this part being a function of the number of compensation points, ie the correspondingly designed toothing elements, and / or the geometry of the individual gear elements; 2. Use as a safety clutch in the form of an overrunning clutch, in which the flanks of the two mutually engaging Hirth toothings of the two machine elements to be coupled slide against one another when a predefined axial force is exceeded.

The asymmetrical structure is achieved in that a first flank of the individual toothing elements is made steeper than the other second flank. The position of the flanks can be described using the flank angle, which is the one that can be described by the individual flank

Plane and a plane running perpendicular to the head height line of the toothing or the toothing element, which plane can be described by a line that runs perpendicular to the axis of rotation and through the head height line and the axis of rotation. The first, preferably steeper flank, viewed in a rotational direction or in the circumferential direction, preferably takes an angle between 0 ° <29 °. The second flatter flank of a toothing element takes up an angle of 29 <80 °, preferably <80 °. However, a negative flank angle is also conceivable, so that the machine elements get caught in the operating state. The angle of the flanks is understood to mean the angle that lies between the

Plane, which is described by the flank, and another plane, which is perpendicular to the axis of rotation and extends through the flank. This plane can also be described by the central or rotational axis and a flank line of the individual toothing element. The angle can also be described as follows:

90 ° - angle a. or 90 ° - angle α ₂ , where α ₁ and α _{2 represent} the slope inclination with respect to the head contour line. In the first case, ie to compensate for the axial forces that occur, the direction of rotation is such that the surface of the toothing flank with the steeper flank points or is directed in the circumferential direction against the direction of rotation. In a preferred embodiment, the steeper flank is designed as a straight flank, ie with an angle of 90 ° with respect to the head line, so that a flank angle of 0 ° is achieved. In addition to realizing the function of self-centering of the individual machine elements to be coupled with Hirth stimulating teeth, this embodiment is characterized by a low manufacturing outlay.

In the second case, i.e. When using the Hirth toothing for connections that function as a safety or overrunning clutch, the design of the individual toothing elements takes place in such a way that the steeper flank, viewed in the circumferential direction, points in the direction of the direction of rotation. In this case, the geometry of the individual is interpreted

Gearing, in particular the flatter flank, a sliding of the flanks of the intermeshing gears of the two machine parts when a certain predefined axial force is exceeded.

Between the individual, adjacent to each other in the circumferential direction

Tooth is a tooth base, preferably in a rounded shape, incorporated. The tooth head of the Hirth toothing is preferably designed as a flat surface.

There are a multitude of possible uses for the arrangement and configuration of the individual toothing elements. These include:

1. Arrangement of the individual gear elements in the circumferential direction, based on the axis of rotation of the machine element over the entire circumference; 2. Arrangement of individual gear elements in partial areas, based on the circumferential direction.

In the former case, there is preferably the possibility of designing the individual toothing elements analogously with regard to their geometry, so that a toothed ring is formed in the circumferential direction on a diameter in relation to the axis of rotation. This possibility represents a preferred embodiment, which is characterized by simple manufacture and, by the corresponding number of flanks available, enables optimal compensation of the axial force.

In the second case, individual toothing elements can either be combined to form a single toothing element or a form-fitting connecting element, or, viewed over the circumference, partial areas can be designed entirely free of toothing. In addition, the gear elements can have a uniform or different geometry. If gaps are provided or gearing elements combined from several individual elements, it must be taken into account that the counter element must be designed accordingly. There are a number of options for this. A first possibility consists in the mutually complementary design of the gap area and the toothing segment, so that the two machine elements essentially also lie in these areas over larger areas. Furthermore, the toothed elements combined from several toothed elements can be designed with a lower head height than the adjacent toothed elements on the same machine element, so that in this area a flat superimposition of the two machine elements to be coupled with one another is achieved, this area being optimal for the accommodation or Arrangement of connecting elements can be used, or larger spaces remain between the two machine elements. 7

The design, geometry and / or the definition of dimensions of the individual toothing elements can be carried out analogously to other toothing elements in the different design variants; the toothing elements are preferably produced with a uniform geometry and uniform dimensions. Another possibility, however, is to design individual toothing elements differently from one another with regard to their geometry and / or their dimensions.

The asymmetrical teeth are preferably designed with regard to their geometry such that flanks aligned in the same direction, the direction being described by the course of the flank plane, each point in one direction with respect to the circumferential direction. With the same orientation of the flanks, the function is determined depending on the direction of rotation. Steeper flanks than first

Flanks viewed in the circumferential direction during rotation cause tension. Steeper flanks, viewed as the second flank of a toothed element in the circumferential direction when rotating, serve to implement the second function as an overrunning clutch. However, there is also the theoretical possibility, not explained in further detail, of designing the individual toothing elements in terms of their geometry and / or dimensions in such a way that both axial force components can be supported in one and in the other direction of rotation of the machine element. This is preferably achieved by considering individual ones in the circumferential direction of the machine element

Segments are created which are provided with toothings of different toothing geometries, in particular their flank planes, viewed in the circumferential direction, are oriented opposite to one another. Such an implementation, however, presupposes an increased manufacturing outlay, which is due to the universal

Applicability is compensated regardless of the direction of rotation. 8th

The asymmetrical toothing can be manufactured using milling cutters or grinding wheels. Furthermore, it is possible to drop-forge the individual gears by means of shaping, sintering and rolling. In this case, impact hardening can also take place. The functions of torque / speed transmission and the increase in accuracy and repeatability are also optimally fulfilled with the asymmetrically designed Hirth toothing. The stresses can be minimized by appropriately designed surface pressures. The use cases themselves can be designed in many different ways. It is irrelevant in which installation position the machine elements and thus the alignment of the Hirth splines are. Representative as possible application examples are the use in cardan shaft, as a connection and power transmission element for use in nuclear reactors, gyroscopes, e.g. Compressors, fans and in

Called machine tool manufacturing.

The concrete selection of the geometry of the individual toothing element, the entire toothing in the circumferential direction, in particular the use of the possibility of combining individual toothing elements into one

Gear element or the possibility of executing gear arrangements with gap areas depends on the specific application and the loads occurring there and is therefore at the discretion of the responsible specialist. By means of the solution according to the invention, the advantages of a Hirth spline are optimally used, with the additional possibility of considerably reducing the axial forces required for pretensioning the two machine elements to be coupled to one another and thus also the number of means required to apply this pretensioning force for a specific one Direction of rotation can be reduced, and furthermore at the same

Alignment of the flanks of the successive gear elements in the other connecting direction, the same connecting element can be used as a safety clutch.

The solution according to the invention is explained below with reference to figures. The following is shown in detail:

1a shows a possible embodiment of a Hirth spur toothing designed according to the invention for realizing a form-fitting and self-centering connection between two machine parts to be coupled to one another using one

Detail from both;

Fig. 1 b illustrates the slope of the individual

Gear element describing angle in a developed representation of individual successive

Gear elements corresponding to Fig. 1a;

2 illustrates an embodiment with asymmetrical toothing elements designed according to the invention, the toothing having partial areas which are characterized by the combination of individual toothing elements which are adjacent to one another to form a single toothing element;

3 illustrates a further possible embodiment of a machine element with a Hirth

Spur toothing, the toothing extending in the circumferential direction having gap regions which are free from toothing elements; 10

Fig. 4 illustrates an embodiment of a machine element with

Suitability for any direction of rotation by using individual segments of different geometry and orientation;

5 illustrates an embodiment with a negative flank angle.

FIG. 1a illustrates the basic principle of the Hirth spur toothing 1 designed according to the invention in a simplified representation using an exemplary embodiment. Two machine elements to be coupled with one another for the purpose of torque transmission, a first one

Machine element 2, which can be coupled at least indirectly with a drive machine, not shown in detail here, and a second machine element 2 ', which can be coupled at least indirectly with an output, not shown here in detail, are each provided with complementary Hirth stimulating teeth 1 or 1 'designed. The Hirth spur toothing 1 or 1 'is based on the basic idea that all geometrical lines of a spur toothing are wedge-shaped and converge centrally at one point, here the point G. These individual geometric lines are shown by way of example in FIG. 1a for three gear elements. The three

Gear elements are designated 3, 4 and 5. The corresponding geometric lines are each designated 3 ', 4', 5 'or 3 ", 4" and 5 "or 3'", 4 '"and 5"'. These geometrical lines are defined by the intersection of the theoretically conceived lines on the individual toothing element, which describe and extend the flanks, and the

Intersections of the theoretical lines extending the flanks can be described with a base line G _L running in the circumferential direction parallel to the tooth height ZH. In the case shown, the individual flanks of the individual toothing element - a first flank and a second flank - are each designated 3a, 4a or 5a and 3b, 4b or 5b for the toothing elements 3, 4 or 5, which are designated as examples. The flanks 3a, 4a and 5a and 11

3b, 4b and 5b when the cross section is projected into a plane describing theoretical lines are denoted by 6, 6 'or 6 "and 7, 7' or 7". The theoretical lines labeled 6 are assigned to the edges 3a, 4a and 5a, and the theoretical line labeled 7 describes the edges 3b, 4b and 5b.

The Hirth spur toothing 1 or 1 'designed according to the invention is characterized in that the individual toothing element is designed asymmetrically. This means that the individual flanks, here representative flanks 3a or 3b, 4a or 4b and 5a or 5b of the individual toothing elements, here 3, 4 or 5, run at different angles to one another. Preferably, as shown in FIG. 1a, the individual toothing elements, which are arranged at preferably uniform distances from one another over the circumference U of the first or second machine element 2 or 2 ', are constructed with the same geometry.

Specifically, this means that the distances between two arbitrarily selected points of two adjacent toothing elements, which are located on a common diameter with respect to the axis of rotation or central axis, are constant. FIG. 1a illustrates this by way of example for the individual toothing elements 9 and 10 using the

Points 11 and 12, the distance is labeled a. In analogy, this also applies to the distances between the individual rectified flanks, for example 3a, 4a, 9a, 10a, 5a or, for example, 3b, 4b, 9b, 10b, 5b of the individual toothing elements which are successive or adjacent in the circumferential direction.

For the purpose of torque transmission between the first machine part 2 and the second machine part 2 ', the Hirth splines 1 and 1', which are complementary to each other, are brought into engagement with one another. The Hirth spur gearing 1 or 1 'on the individual machine elements 2 or 2' enables a positive fit 12

Connection between these. The asymmetrical configuration according to the invention has the effect that a force component which at least partially corresponds to the axial prestressing force for prestressing the two machine elements 2 and 2 'is generated. To do this, however, it is necessary to design the geometry of the toothing in accordance with the direction of rotation. This geometry is essentially determined by the angle of the flanks. The flanks 3a, 4a and 5a describe a plane E1 _3a , E1 _4a and E1 _5a via their extension b in the radial direction to the central center G, which is simultaneously on the axis of symmetry or axis of rotation of the machine element 2 or 2 ' or E2 _3b , E2 _4b and E2 _5b . The angle of the flanks can then be represented as the angle of these planes E1 and E2 with respect to the line describing the head height Z _{H of} the individual toothing element.

For this purpose, a section of the Hirth

Front teeth 1 of the machine element 2 shown in the circumferential direction in a developed form. The two toothing elements 4 and 9, which are adjacent in the circumferential direction, are represented here. The line describing the head height Z _H always runs in a plane which is perpendicular to a through the plane of symmetry of the

Machine element 2 or 2 'plane, which can be described by the axis of symmetry S and a line perpendicular to this, runs. The angle of the planes E1 and E2 described by the flanks with the line describing the head height Z _H serves to describe the geometry of the toothings. In the case shown, the angle of the flank 4a or 9a with the plane or the top line Z _H with α1 and the angle of the flank 4b or 9b with the plane or top line with α2.

By subtracting 90 ° - a. or 90 ° - α ₂ results in the flank angle.

Preferably, as shown in FIG. 1a, the individual ones 13

Gear elements which follow one another in the circumferential direction of the machine element 2 are designed with the same geometry. The size of the axial pretensioning forces applied by the geometry of the toothing, which are required for the torque transmission between the two machine elements 2 and 2 ', is a function of

Number of gear elements and the geometry, especially the angle of the individual flanks. The steeper flank of both flanks is preferably designed with a flank angle between 0 degrees and 29 degrees and the angle of the flatter flanks with an angle between 30 and 80 degrees. The size of the angles is preferably selected such that they lie below the self-locking limit. However, it is also conceivable to obtain a negative flank angle for the steeper flank.

There is theoretically also the possibility, not shown here in detail, of executing the individual toothing elements with different geometries adjacent to one another in the circumferential direction of the machine element 2 or 2 ', the first and second flanks of two mutually adjacent toothing elements which are successively aligned in the circumferential direction being aligned identically.

The asymmetrical configuration according to the invention of the toothing elements which follow one another in the circumferential direction of the machine elements and which bring about a reduction in the axial forces required for pretensioning the two machine elements in the axial direction against one another makes it possible to use additional ones

Means for generating the axial preload between the two machine elements 2 and 2 'can be dispensed with. The direction of the axial pretensioning forces is described by a parallel to the axis of symmetry or during operation of the axis of rotation of the machine elements 2 or 2 '. Since the use of the means required to generate the axial pretensioning force can be largely reduced, there is no need 14

Additional constructive measures on the individual machine elements 2 or 2 'for receiving these means, for example in the form of bores, which can also be arranged in the area of the teeth of the machine elements. This offers the advantage that the toothing can be used completely for power, in particular torque transmission.

Since the basic idea is to form all the geometric lines of a spur toothing in a wedge shape and to bring it together centrally at one point and the end faces are tapered to achieve a tooth tip surface delimited by parallels, i.e. the tooth top surfaces with parallel

Executing side lines has not changed anything, the advantages of the conventionally designed Hirth spur toothing can be achieved with the solution according to the invention. The geometric configuration according to the invention also enables the production of a positive self-centering connection. The Hirth spur toothing as a form-fitting, self-centering connecting element can be used as a space-saving part element with high partial accuracy or as a fixing element with high repeatability. The assembly itself is relatively simple, and individual machine elements are easily interchangeable.

FIG. 2 illustrates a further design option for the Hirth spur toothing designed according to the invention. The basic principle and basic structure of the Hirth spur toothing, in particular of the individual toothing elements, essentially corresponds to that described in FIG. 1, which is why the same reference numerals are used for the same elements. The decisive difference is that the individual toothing elements are not designed with the same geometry in the circumferential direction of the machine element 2. The solution according to Figure 2 is characterized in that individual

Tooth elements according to Figure 1a to an individual 15

Gear element can be summarized. In the case shown, these are the two toothing elements 14 and 15. These preferably have the same angles with respect to their flanks 14a or 15a and 14b or 15b as those of the other toothing elements which are adjacent to one another, but these each form a stop face, here with 16 for the

Gear elements 14 and 17 designated for the gear element 15, for a corresponding stop surface on the machine element 2 'to be coupled to the machine part 2. This stop surface 16 or 17 is formed by the top surface of this toothed element 14 or 15, which is widened in the circumferential direction. Preferably these

Areas in the case of rotation of symmetrically designed elements are used to accommodate the bores or threads to be provided to hold the individual machine elements 2 or 2 'together. The embodiment described in FIG. 2 of combining individual toothing elements into one toothing element with others

Dimensions compared to the remaining remaining gear elements is only one possible version of many. Depending on the application, the summary can vary with regard to the number of gear elements to be combined and the number of acquisitions to be made. In addition, there is

Possibility of designing the individual gear elements, including those created by combining, with different geometries from one another. In particular, the individual toothings can differ with regard to the angles of the flanks.

The embodiments of the embodiment of a Hirth spur toothing according to the invention described in FIGS. 1 and 2 are preferably used for the form-fitting coupling of two machine elements 2 or 2 'to reduce the axial pretensioning forces during operation in one direction of rotation. This direction of rotation is shown in FIG. 1. In this case, the number of means for applying a 16

axial preload between the two machine elements 2 and 2 'can be greatly reduced. At an angle of the first flank in the direction of rotation of 0 degrees u. Depending on the application, additional means for applying an axial pretensioning force between the two machine elements to be coupled with one another can be dispensed with entirely.

However, it is also conceivable to use a negative angle for the steep flank. The second machine element then hooks into the first machine element. This possibility is shown in Fig. 5.

The asymmetrical configuration of the Hirth

Spur toothing also offers the possibility of using the two machine elements designed with complementary toothings as safety clutches in the form of a so-called overrunning clutch. This is the case if the use for the purpose of torque transmission in a direction of rotation of the first

Machine part 2 takes place contrary to that shown in FIG. 1a. In this case, depending on the magnitude of the axial forces occurring, the individual flanks of the two flanks of the two mutually complementary toothings 1 and 1 'provided with one another can slide. The sliding takes place on the flatter one

Flank, which is then the first flank of the individual toothing element in the direction of rotation.

The solution according to the invention can be used as a connecting element in a large number of examples of applications for torque transmission. The specific design, ie the design of the geometry and the arrangement on the individual elements to be coupled with one another and the choice of the installation position, are carried out in accordance with the specific application. The possible embodiments shown in FIGS. 1 and 2 only serve to illustrate the basic principle of the mode of operation of one 17

asymmetrically designed Hirth spur gearing and are therefore in no way intended as a restriction to these two exemplary embodiments.

Another possibility of designing a machine element with the Hirth spur toothing designed according to the invention is shown in FIG. It can be seen from this that it is in no way necessary to provide the individual toothing elements with a constant spacing and the same geometry in the circumferential direction of the individual machine element 2. Here too, the individual toothing elements form toothing segments according to FIG. 2, although in FIG. 3 no individual toothing elements are combined to form a toothing element, but toothing elements are removed from the toothed ring. This then creates so-called segments which are arranged in the circumferential direction of the machine element and are free of toothing. These are representative of 18, 19, 20 and

Designated 21. The toothed segment 19 comprises several individual toothed elements. The geometry of the individual toothing elements, which are arranged between the toothing elements, the toothing segments and the number of toothing segments, is designed according to the specific application requirements of the individual case.

FIG. 4 illustrates in a schematically simplified representation using a machine element 2.4 a further embodiment for an asymmetrical Hirth spur toothing designed according to the invention. Only one machine element has been shown, the second is complementary to the first in terms of toothing. For this purpose, both machine elements 2.4 and the second machine element designed with complementary toothing and not shown here comprise areas which can also be referred to as segments 23 or 24 and 25 or 26, which are characterized in that the individual toothing elements differ in their orientation or opposite 18th

are aligned. The segment 25 of the machine element 2.4 comprises the toothing elements 27, 28, 29, 30, 31, the segment 26 the toothing elements 32 to 36. With respect to the direction of rotation, the flanks of the toothing elements 32 to 36 are opposite to those of the toothing elements, at least with regard to the flatter flank 27 to

31 aligned. This statement also applies to the segments 23 and 24. The machine element complementary to the machine element 2.4 and not shown here has the corresponding complementary toothing. The differently aligned toothing segments make it possible for an axial pretensioning force to be independent of the direction of rotation of the

Machine element, in particular the machine element on the drive side, here designated 2.4, can be used regardless of the direction of rotation. However, in order to achieve a fluid connection between the mutually complementary toothed segments of the individual machine elements 2.4, it is necessary to design the transition area between two differently oriented toothed segments accordingly. This can be achieved, for example, by means of areas free of toothing for machine element 2.4, while the other complementary toothed machine element then has an area on the toothing free area

Fills machine element 2.4 or forms a free space. The gap areas are designated here with 37, 38, 39 and 40.

However, the possibility shown in the figure can only be realized if there is no negative flank angle. The flank angle of the steeper flank is preferably not equal to 0 °.

The segments formed with oppositely aligned toothing are preferably arranged in the circumferential direction in such a way that they are distributed symmetrically over the circumference. In the present case means 19

this is an analog design of the opposing segments 25 and 23 and 24 and 26.

In a further aspect for realizing the suitability of an embodiment according to FIG. 4 only for left or right rotation without transmission of a

Lifting force, the respective passive toothing elements, e.g. 32-36 and the complementary toothing elements on the opposite machine part to be coupled, should be withdrawn (e.g. by milling) so that the oblique flank of the passive toothing elements does not produce any lifting force, while only the

Gear elements 27, 28, 29, 30 and 31 and the opposing gear elements are involved in the torque transmission. With this version, it is possible, depending on the assembly, to transmit torque in the clockwise or counterclockwise rotation with the same components without lifting force. Another design option is the division of the

Spur toothing in four toothing segments, each with the same size gaps for contact-free reception of the toothing elements of the counterpart.

FIG. 5 illustrates in a schematically simplified representation using a

Machine element 2.5 a further embodiment for an asymmetrical Hirth spur toothing designed according to the invention. Only one machine element has been shown, the second is complementary to the first in terms of gearing. Both machine elements 2.5 and the second machine element designed with complementary toothing and not shown here comprise toothing elements, here designated 40, which are characterized in that the individual toothing elements have a negative flank angle with regard to the steeper flank, i.e. the angle simplified representation based on a machine element 2.4, a further embodiment for an asymmetrically designed according to the invention 20th

Hirth spur toothing. Only one machine element has been shown, the second is complementary to the first in terms of gearing. For this purpose, both machine elements 2.4 and the second machine element designed with complementary toothing and not shown here comprise areas which can also be referred to as segments 23 or 24 and 25 or 26, which are characterized in that the individual toothing elements are different or different with regard to their orientation are oriented in opposite directions.

Claims

21 PATENT CLAIMS

1. Hirth-end-toothed machine element, characterized in that individual toothing elements (3, 4, 5, 27-31, 32-36, 40) are asymmetrical.

2. Hirth-toothed machine element according to claim 1, characterized in that the individual toothing element (3, 4, 5, 27-31, 32-36) has a first flank angle of 0 <29 degrees and a second flank angle of 29 <80 degrees , the flank angle being described by the angle of the plane described by the flank (E13a, E14a, E15a, E23b, E24b, E25b) to a plane which corresponds to the plane running perpendicular to the plane of rotational symmetry and by the axis of rotational symmetry (S) and the flank line is characterized.

3. Hirth-toothed machine element according to claim 2, characterized in that the flank angle of the steeper flank is <0 °.

4. Hirth-face-toothed machine element according to one of claims 1 to 3, characterized in that the individual toothing elements (3, 4, 5, 27-31, 32-36) have the same geometry.

5. Hirth-spur-toothed machine element according to one of claims 1 to 4, characterized in that in each case the flank with the flatter inclination in the circumferential direction is formed by the respective first flank of the toothing element.

6. Hirth-toothed machine element according to one of claims 1 to 5, characterized in that a plurality of individual 22

Gear elements are combined into a single gear element (14, 16) to form a stop surface.

7. Hirth-spur-toothed machine element according to one of claims 1 to 6, characterized in that viewed in the circumferential direction at least a portion is provided in the toothing (18, 19, 20) which is free of toothing elements.

8. Hirth-toothed machine element according to one of claims 1 to 7, characterized in that a plurality of individual

Gear elements (27-31, 32-36) are combined to form a gear segment (25, 26, 23, 24), which is characterized in that the gear elements in the individual gear segments are oriented differently with respect to the flank angle.