WO2011160241A1 - Method for producing an inner knurl in a receiving bore of a hub body - Google Patents

Abstract

The invention relates to a method for producing an inner knurl (10) extending in the axial direction in a receiving bore (6) of a hub body (3) for forming a hub connection between the hub body (3) and a wave body (1), in particular by pressing the hub body (3) in the axial direction to the wave body (1). According to the invention, the inner knurl (10) is produced by rolling a straight knurling tool (11) over the inner surface of the receiving bore (6). This enables a hub body (3) to be produced in an economical manner comprising form-fit contours for a complimentary peripheral hub connection in the receiving bore (6).

Description

 Method for producing an inner knurling in a Au bore of a hub body

TECHNICAL AREA

 The present invention relates to a method for producing a running in the axial direction Innenrändelung in a receiving bore of a hub body, a hub body made with the method ren and a shaft assembly comprising such

Hub body according to the preambles of the independent claims.

STATE OF THE ART

 For the production of hub connections between a shaft body and a hub body various techniques are known today.

 So it is e.g. It has long been common practice in mechanical engineering to connect hub bodies with a cylindrical receiving bore by pressing or shrinking them onto a cylindrical seat with a shaft body. It is also known to connect such shaft body and hub body via clamping sleeves with each other.

 However, such interference fit hub connections have the disadvantage that the transferable with them

Torque due to the purely positive connection between the hub body and shaft body against positive hub connections is relatively low and also highly dependent on the component temperatures.

If the hub connection produced by pressing or shrinking, there is also the disadvantage that this joining method requires tight tolerances on the diameter of the receiving bore and the seat, which is more demanding on the production and is associated with corresponding costs. If the hub connection is made via a clamping sleeve, there are considerable additional costs for the adapter sleeve. Also, the clamping sleeve requires additional space, whereby the diameter of the receiving bore of the hub body is increased and, accordingly, the required minimum external dimensions of the same.

 In the form-locking hub connections known today, the shaft body and the receiving bore of the hub body are joined prior to joining by means of machining processes with corresponding form-fitting contours or with positive-locking contours for receiving auxiliary parts, such as, for example, of feather keys, provided. These hub connections have most of the aforementioned disadvantages of the purely non-positive hub connections, but instead the great disadvantage that the production of such form-fitting contours is very expensive, especially in the receiving bore of the hub body, whereby the hub body and with it the entire hub connection is very expensive.

PRESENTATION OF THE INVENTION

 It is therefore an object to provide a method for producing form-fitting contours for a positive hub connection in the receiving bore of a hub body and a hub body available that do not have the aforementioned disadvantages of the prior art, or at least partially avoided.

 This object is solved by the subject matters of the independent claims.

Accordingly, a first aspect of the invention relates to a method for producing an axially extending internal knurling in a receiving bore of a hub body to form a hub connection between the hub body and a shaft body, preferably by pressing the hub body into axial direction on the shaft body. According to the invention, the inner knurling is produced by rolling over the inner surface of the receiving bore with a knurling tool.

 This makes it possible to inexpensively provide a hub body available, the form has final contours for a circumferentially positive hub connection in its receiving bore.

 Advantageously, a polygonal or substantially circular inner knurling is produced. It is also preferred if an inner knurling is produced, which uniformly distributed over the circumference of the inner surface of the receiving bore knurls. Such knurls can be produced particularly well by rolling over the inner surface of the receiving bore with a knurling tool.

 In a preferred embodiment of the method, the inner surface of the receiving bore is passed over only in a partial region of its axial extension with the knurling tool, in another preferred embodiment over its entire axial extent. Depending on the use of the hub body or the design of the hub connection to be made with it, one or the other embodiment may be more advantageous.

 Preferably, the inner surface of the receiving bore is rolled over its entire circumferential extension with the knurling tool, to produce an inner knurling over the entire circumference of the receiving bore. As a result, the entire circumference of the receiving bore to form a positive connection in the circumferential direction is made usable.

In the case of embodiments in which the inner surface of the receiving bore is only passed over in a partial region of its axial extension with the knurling tool, it is preferred that this portion extends from one end of the receiving bore into the receiving bore. In this way, an inner knurling, which results at one end of the receiving bore the front side is completely open, so that the entire knurling depth is usable for a positive connection.

 In yet another preferred embodiment of the method, the inner surface of the receiving bore for generating the Innenrändelung is repeatedly passed over with the knurling tool. As a result, the degree of deformation and with this the strength of the knurling is increased.

It is also preferred that advertising hardened the knurled Innenrändelung the roll by over ^¬ generated to. As a result, these are particularly resistant and are, for example, also particularly well for pressing on a seat with a smooth surface of a shaft body under a Einfurchen the knurl in this surface.

 A second aspect of the invention relates to a hub body, preferably made of metal, with a

Receiving bore with an axially extending Innenrändelung, which is produced by the method according to the first aspect of the invention. Such hub bodies can be produced relatively inexpensively in comparison with comparable prior art hub bodies.

 In a preferred embodiment of the hub body, the inner knurling forms a substantially circular cylindrical inner contour of the receiving bore.

 In another preferred embodiment of the hub body, the inner knurling forms in a partial region of its axial extent over its entire axial extension a circumference or stepwise increasing in the axial direction in its circumference, preferably a truncated cone-shaped inner contour of the receiving bore.

 Depending on the configuration of the shaft body provided for forming a hub connection with the hub body, one or the other embodiment may be more advantageous.

Extend the knurls of Innenrändelung seen in the longitudinal direction parallel to the longitudinal axis The receiving bore of the hub body, which is preferred, there is the advantage that the positive connection of a hub connection made with the hub body in the axial direction is neutral, ie that no load axial force components occur under load in the circumferential direction.

 In a further preferred embodiment, the hub body has a ratio of the mean diameter of its receiving bore to its smallest wall thickness in the radial direction of greater than 10, preferably. Greater than 15. In such "thin-walled" hub bodies, the advantages of the invention are particularly evident.

 Further, it is preferred that the receiving bore of the hub body has a curved introduction bevel, which merges into the inner surface of the receiving bore substantially without transition. This is used for self-centering in the manufacture of a hub connection with a shaft body and reduces, especially in hub connections, in which there is an interference fit between the hub body and a shaft body, the risk of abrupt Aufpresskraftstössen when joining and thus the risk of damage to the hub body.

 In this case, introduction bevels have proven to be particularly suitable, which extend starting from the inner surface of the receiving bore according to the following function:

Y = X ² * tan α / (2 * FL)

In this function, Y is the radial extension of the lead-in chamfer, X is the axial extent from the receiving bore, FL is the total length of the lead-in chamfer, and α is the chamfer angle at the end face of the hub body. This function results in a steady slope of the chamfer angle from 0 ° to the end face. Preferably, the inventive

Hub body designed as an eccentric body, gear or crank.

 A third aspect of the invention relates to a shaft assembly with one or more hub bodies according to the second aspect of the invention and a shaft body on which the hub bodies are respectively, preferably by pressing, attached to the Längsrändelungen their receiving holes. The formation of such a shaft arrangement corresponds to the intended use of the hub body according to the second aspect of the invention.

 In a preferred embodiment of the shaft arrangement, the shaft body has one or more sections with a longitudinally-knurled outer contour, on which the hub body or bodies are fastened, preferably by pressing in the axial direction onto the longitudinally aligned outer contours. In this case, the longitudinal knurls of the longitudinally knurled outer contour of the respective section and the inner knurling of the receiving bore of the hub body arranged on this section engage one another. In such shaft arrangements of the positive connection between the hub body and shaft body is particularly pronounced.

 In this case, it is further preferred that the longitudinally aligned outer contours of the sections of the shaft body are progressively or gradually increasing in circumference, starting from an end of the section over a partial region of the longitudinal extension of the section or over its entire longitudinal extent.

As a result, in the production of the respective hub connection, the self-centering is improved and, in particular in the case of producing a hub connection, in which there is an interference fit between the hub body and the shaft body, reduces the risk of abrupt Aufpresskraftstössen when joining and thus the risk of damage to the hub body , BRIEF DESCRIPTION OF THE DRAWINGS

 Further embodiments, advantages and applications of the invention will become apparent from the dependent claims and from the following description with reference to FIGS. Showing:

 1 shows a section through a first inventive hub body;

 FIG. 2 shows a front view of the hub body of FIG. 1 during production of the inner knurling in its receiving bore; FIG.

 3 shows a section through a second hub body according to the invention;

 Figures 4a-4e are side views of various shaft body to form a shaft assembly according to the invention with the hub body of Figure 1 or Figure 3 ..;

 FIG. 5 shows the shaft body from FIG. 4b when a hub body is pressed onto its longitudinal knurl to form a shaft arrangement according to the invention; FIG. and

 Fig. 6 is a representation as the detail X of FIG. 5, but with a hub body according to the invention with a curved Einführfase.

WAYS FOR CARRYING OUT THE INVENTION

 A first embodiment of a hub body 3 according to the invention is shown in section in FIG.

The hub body 3 has a receiving bore 6 with an axially running internal knurling 10 for engaging in corresponding longitudinal knurls 4 of the knurled portions 2 of the shaft bodies 1 shown in FIGS. 4a and 4b or for indenting into the surfaces of the smooth-surfaced portions 12 that shown in Figures 4d and 4e Shaft body 1 after pressing the hub body 3 on the respective shaft body. 1

 As can be seen, the inner boundary 10 forms a circular cylindrical knurled inner contour of the receiving bore 6 over a large part of the axial extent of the hub body 3, to which a section c with a circular cylindrical smooth inner contour and then on the hole side pointing in the pressing direction P an introduction bevel 7 connects.

 The inner knurling 10 consists of uniformly distributed over the entire circumference of the receiving bore 6 identical and parallel to the longitudinal axis of the receiving bore 6 extending knurls, which, as shown in Fig. 2, which shows the hub body 3 when generating the Innenrändelung 10, by rolling the Inner surface of the receiving bore 6 are generated with a rolling tool 11.

 3 shows a second embodiment of a hub body 3 according to the invention in section. This hub body 3 differs essentially from the hub body 3 shown in FIG. 1 in that the inner knurling 10 forms an inner contour of the receiving bore 6, which gradually increases in its circumference in its axial extent over its axial extent. Here, too, the hub body 3 has a significantly thicker wall.

 FIGS. 4a-4e show side views of different shaft bodies for forming a shaft arrangement according to the invention with the hub body from FIG. 1 or FIG. 3.

As can be seen, the shaft bodies 1 are each formed in one piece and each have a portion 2 with a longitudinally-knurled outer contour (Figures 4a-4c) or a portion 12 with a smooth seat contour (Figures 4d-4e), as well as right and left thereof respectively a section 9 with a smooth outer contour. While the latter sections 9 are consistently formed as a circular cylinder, the sections 2 and 12 are formed differently with the longitudinally smoothed or smooth outer contour in the three embodiments.

 In the embodiment illustrated in FIG. 4a, the longitudinally-knurled outer contour is progressively and continuously increasing over one first section a of its longitudinal extension L, such that section 2 in this first section a has a truncated cone shape with longitudinal outer contour. The pitch angle with respect to the longitudinal axis of the shaft body 1 is here about 10 °. In the other, second portion b of the section 2 is formed as a circular cylinder with a longitudinally knurled outer contour. As can be seen, the frustoconical portion a of section 2 has a smallest

Outer diameter equal to the outer diameter d of the left portion 9 with the smooth outer contour and a largest outer diameter equal to the outer diameter Dl of the second portion b of the longitudinally knurled section 2 on. In the present case, the first portion a extends approximately over one third of the longitudinal extent L of the slow knurled portion 2.

 In the embodiment illustrated in FIG. 4b, the longitudinally-knurled outer contour is progressively and continuously increasing circumferentially, starting from one end of section 2 over its entire longitudinal extension L, such that the entire longitudinally-knurled section 2 has a truncated cone shape. As can be seen, the section 2 here has a smallest outer diameter equal to the outer diameter d of the left section 9 with the smooth outer contour and a largest outer diameter Dl. The pitch angle with respect to the longitudinal axis of the shaft body 1 is about 3 ° here.

In the embodiment shown in FIG. 4c, the longitudinally-knurled outer contour is starting from one end of section 2 over its longitudinal extent L gradually increases in circumference, such that the section 2 is formed in a first subarea a as a circular cylinder with a longitudinal outer contour with an outer diameter D3 greater than the outer diameter d of the left section 9 with the smooth outer contour and in a second portion b, which adjoins directly to the first portion a, as a circular cylinder with längsgerändelter outer contour with an outer diameter Dl, which is greater than the outer diameter D3 of the first portion of section 2. In the present case, the two sections a, b each extend over one half of the longitudinal extent L of the slow-moving section 2.

 The three embodiments according to FIGS. 4a to 4c have in common that the longitudinal extent L of the longitudinally-knurled portion 2 is greater than two-thirds of the largest diameter D1 of the respective section 2, that the longitudinally-knurled outer contour is formed by longitudinal knurls 4 distributed uniformly over the circumference of the outer contour is and that is the

Longitudinal knurl 4 each viewed in the longitudinal direction parallel to the longitudinal axis of the respective shaft body 1 extend.

 The two embodiments of the shaft body 1 according to FIGS. 4d and 4e differ from the embodiments illustrated in FIGS. 4a and 4b only in that their sections 12 have a smooth outer contour instead of a longitudinally contoured outer contour into which the inner knurls 10 of the hub bodies 3 are made Figures 1 and 3 can be feared by pressing.

Fig. 5 shows the shaft body 1 of Fig. 4b when pressing a hub body 1 similar to that shown in Fig. 1 on its longitudinally knurled portion 2 to form a shaft assembly according to the invention. The hub body 3 is shown cut. Here, the difference between the outer diameter d of the left cylindrical portion 9 with a smooth outer contour and the inner diameter D2 of the receiving bore 6 of the hub ^¬ body 3 exaggerated large.

 As can be seen, the receiving bore 6 of the hub body 3 is provided over the major part of the axial extension of the hub body 3 with an inner knurling 10 extending in the axial direction, which forms a substantially circular cylindrical inner contour of the receiving bore 6. At the bore side pointing in the pressing-on direction P, the receiving bore 6 merges with an introduction bevel 7 into the end face 8 of the hub body 3.

 In the present case, the ratio of the inner diameter D2 of the receiving bore 6 of the hub body 3 to the smallest wall thickness W in the radial direction of the hub body 3 is about 2, so it is a relatively thick-walled hub body third

FIG. 6 shows a representation like the detail X of FIG. 5, but with a hub body 3 according to the invention with another introduction chamfer 7. This hub body 3 has a curved introduction chamfer 7, which merges into the cylindrical inner surface 5 of the receiving bore 6 substantially without transition , In this case, the introduction chamfer 7 expands starting from the inner surface 5 of the receiving bore 6 in accordance with the function Y = X ² * tan α / (2 * FL), where Y is the radial extension of the introduction chamfer 7, X is the axial extent starting from the receiving bore 6, FL is the total length of the introduction chamfer 7 and the corner angle on the end face 8 of the hub body 3.

 While preferred embodiments of the invention are described in the present application, it should be clearly understood that the invention is not limited to these and may be practiced otherwise within the scope of the following claims.

Claims

1. A method for producing an axially extending Innenrändelung (10) in a receiving bore (6) of a hub body (3) for forming a hub connection between the hub body (3) and a Shaft body (1) in particular by pressing the hub body (3) in the axial direction of the shaft body (1), characterized in that the Innenrändelung (10) by rolling the inner surface of the receiving bore (6) with a knurling tool (11) is generated.  2. The method according to claim 1, characterized in that the inner surface of the receiving bore (6) only in a partial region (a) of its axial extent with the knurling tool (11) is passed.  3. The method according to claim 1, characterized in that the inner surface of the receiving bore (6) over its entire axial extent (L) with the knurling tool (11) is passed.  4. The method according to any one of the preceding claims, characterized in that the inner surface of the Receiving bore (6) is passed over its entire circumferential extent with the knurling tool (11).  5. The method according to claim 2 and claim 4, characterized in that a partial region (a) of the axial extent (L) of the inner surface of the receiving bore (6) with the knurling tool (11) is passed, extending from one end of the receiving bore ( 6) extends into the on ahmebohrung (6) inside.  6. The method according to any one of the preceding claims, characterized in that the inner surface of the Receiving hole for generating the Innenrändelung (10) is repeatedly passed over with the knurling tool (11). 7. The method according to any one of the preceding claims, characterized in that the knurls of the Innenrändelung (10) generated by rolling over are hardened. 8. hub body (3), in particular made of metal, with a receiving bore (6) with an axially extending Innenrändelung (10), prepared by the method according to any one of the preceding claims.  9. hub body (3) according to claim 8, characterized in that the Innenrändelung (10) in the Essentially circular cylindrical inner contour of the receiving bore forms.  10. hub body (3) according to claim 8, characterized in that the inner knurling (10) at least in a partial region of its axial extent (L) in the axial direction in its circumference continuously or gradually increasing, in particular frusto-conical inner contour of the receiving bore (6) ,  11. hub body (3) according to one of claims 8 to 10, characterized in that the Innenrändelung (10) over its entire axial extent in the axial direction in its circumference continuously or gradually increasing, in particular frusto-conical inner contour of the receiving bore (6).  12. hub body (3) according to any one of claims 8 to 11, characterized in that the knurls of the inner knurling (10) each seen in the longitudinal direction extend parallel to the longitudinal axis of the receiving bore (6).  13. hub body (3) according to any one of claims 8 to 12, characterized in that the hub body (3) has a ratio of the mean diameter (D2) of the inner contour of its receiving bore (6) to its smallest wall thickness (W) in the radial direction of greater than 10, in particular greater than 15. 14. hub body (3) according to one of claims 8 to 13, characterized in that the hub body (3) has a curved insertion bevel (7), which merges into the inner surface of its receiving bore (6) substantially without transition. 15. hub body according to claim 14, characterized in that the introduction ase (7), starting from the inner surface of the receiving bore (6) according to the function Y = X ² * tan a / (2 * FL), where Y is the radial extension of the introduction chamfer (7), X is the axial extent starting from the inner surface of the receiving bore (6), FL is the total length of the introduction chamfer (7) and α the chamfer angle is at the end face (8) of the hub body (3).  16. hub body (3) according to one of claims 8 to 15, characterized in that it is an eccentric body, a gear or a crank.  17 shaft assembly comprising one or more hub body (3) according to any one of claims 8 to 16 and a shaft body (1) on which the hub body (3) in each case in particular by pressing with their mounting holes (6) are attached.  18. Shaft arrangement according to claim 17, characterized in that the shaft body (1) has one or more sections (2) with a longitudinally externally contoured contour and the hub bodies (3) are each pressed onto one of these sections (2) such that in each case the inner knurling (10) of the receiving bore (6) engages in the longitudinally knurled outer contour.  19. Shaft arrangement according to claim 18, characterized in that the longitudinally aligned outer contours of the sections (2) each starting from one end of the section (2) at least over a partial region (a) of the longitudinal extent (L) of the section (2) continuously or stepwise in Scope are increasing.