WO2011160240A1

WO2011160240A1 - Wave body having a section with a longitudinally knurled outer contour

Info

Publication number: WO2011160240A1
Application number: PCT/CH2010/000161
Authority: WO
Inventors: Peter Meusburger
Original assignee: Jansen Ag
Priority date: 2010-06-22
Filing date: 2010-06-22
Publication date: 2011-12-29

Abstract

The invention relates to a wave body (1) comprising a section (2) having a longitudinally knurled outer contour, for forming a hub connection between the wave body (1) and a hub body (3) by pressing said hub body (3) onto the longitudinally knurled outer contour in the axial direction (P). The longitudinally knurled outer contour is formed by having an increasing diameter starting from one end of the section (2) at least over one partial area (a, L) of the section (2). The pressing force increases gradually in a smooth manner in said claimed embodiment of the wave body (1) when assembling and thus effectively reducing the risk of preliminary damage to the hub body (3) during production and increased risk of flaws as a result of abrupt, sporadic force fluctuations and/or pushing actions in the hub body (3). As a result, the claimed wave body (1) is also suitable for very thin and/or hardened hub bodies (3).

Description

Shaft body with a section with a longitudinally knurled outer contour

TECHNICAL AREA

The present invention relates to a Wel ^¬ lenkörper having a portion with a longitudinally knurled outer contour and a shaft assembly comprising such a shaft 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 the hub body with a cylindrical receiving bore by pressing or shrinking it 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 press-fit hub connections have the disadvantage that the torque which can be transmitted with them is relatively low due to the purely frictional connection between the hub body and shaft body compared to positive hub connections and is 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 lent space, whereby the diameter of the

The receiving bore of the hub body is enlarged 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 provided with corresponding form-fitting contours or with positive-locking contours for joining auxiliary parts, such as, for example, before joining. of feather keys, provided. These hub connections have the great disadvantage that the production of such form-fitting contours is very complicated and thus the hub connection is very expensive.

Further, hub connections are known in which a hub body is pressed with a cylindrical receiving bore on a longitudinally knurled portion of a shaft body. Here, the longitudinal knurls furrow in the smooth receiving bore of the hub body, so that a positive and positive hub connection between the hub body and shaft body is created. In this technique for producing a hub connection, however, there is a risk that it may come to a pre-damage of the hub body during assembly and to increased risk of cracking due to abrupt, jerky force fluctuations or impact effects in the hub body, so this process does not without restrictions for very thin or hardened hub body.

PRESENTATION OF THE INVENTION

It is therefore an object to provide solutions for the production of hub connections between a shaft body and a hub body, which do not have the aforementioned disadvantages of the prior art or at least partially avoid them. This object is solved by the subject matters of the independent claims.

Accordingly, a first aspect of the invention relates to a shaft body, preferably of metal, having a portion with a longitudinally-knurled outer contour, for forming a hub connection between the shaft body and a hub body by pressing the hub body in the axial direction onto the longitudinally-knurled outer contour. The longitudinally knurled outer contour of the shaft body, starting from one end of the section, is progressively more or less progressively circumferentially formed over at least a portion of the section.

This embodiment of the shaft body according to the invention leads to a gentle, material-sparing increase in the pressing force during joining and thus effectively reduces the danger that during the production of the hub connection pre-damage of the hub body and increased risk of cracking due to abrupt, impact-like force fluctuations or from impact effects in the hub body comes. Accordingly, the shaft body according to the invention is also particularly suitable for very thin or hardened hub bodies, in particular for the formation of built-up camshafts and gear shafts.

In a preferred embodiment of the shaft body, the subregion in which the longitudinally contoured outer contour is progressively formed extends at least over one sixth, in particular over one quarter and in particular over one third of the longitudinally interlaced section. The remaining areas of the section advantageously have a circumferentially constant, cylindrical longitudinally-knurled outer contour. Depending on the absolute length of the section, the hub material and the desired torque transmission capability of the hub connection to be produced, one or the other variant may be more advantageous.

In another preferred embodiment of the shaft body is the longitudinally knurled outer contour over the entire section continuously or gradually formed in the scope increasingly. This results in the joining with a hub body with a cylindrical receiving bore over the entire joining process, an increase in the pressing force.

Advantageously, the longitudinally-knurled outer contour of the section is polygonal or essentially circular. Such outer contour ^shapes are particularly suitable for the production of hub connections according to the invention.

Is the Längsgerändelte outer contour in the

Area in which it is increasingly formed in the circumference, evenly increasing in circumference, which is preferred, so results in the joining at a constant joining speed and a hub body with a cylindrical receiving bore until complete entry of the circumferentially increasing area of the longitudinally knurled outer contour steady increase of the pressing force. This is desirable and favors easy monitoring of the joining process by monitoring the Aufpresskraft- course. In this case, the longitudinally-knurled outer contour in the region in which it is increasingly formed in the circumference is preferably uniform with a pitch angle with respect to the longitudinal axis of the shaft body of less than 10 ° and more preferably with a pitch angle with respect to the longitudinal axis of the shaft body of less than 5 ° increasing in scope. Such pitch angle have been found to be particularly suitable in combination with hub bodies with cylindrical mounting holes.

If the longitudinal extent of the section with the longitudinally-knurled outer contour is greater than half, in particular greater than two-thirds of the largest diameter of its longitudinally-knurled outer contour, hub connection with high tilting rigidity can be produced with the shaft body according to the invention. Advantageously, the longitudinally contoured outer contour is formed by longitudinal knurls uniformly distributed over the circumference of the outer contour. This facilitates the production of the longitudinal knurl and also provides the advantage that, viewed over the circumference, a uniform torque transmission capability of the hub connection results.

In further preferred embodiments of the shaft body according to the invention, the longitudinal knurls of the longitudinally-knurled outer contour in the region in which this outer contour is increasingly formed in the circumference increase in width as the length of the longitudinally-knurled outer contour increases, decreasing in width or uniform in width. Depending on the manufacturing process for the longitudinal knurl, the choice of material with respect to the shaft body and / or the hub body and the desired quality of the hub connection, one or the other embodiment may be particularly advantageous.

If the longitudinal knurls of the longitudinally knurled outer contour each extend in the longitudinal direction parallel to the longitudinal axis of the shaft body, which is preferred, then the joining movement for producing a hub connection with the shaft body is a pure translational movement, which can be carried out with simple presses. There is also the advantage that the positive fit of the hub connection produced in the axial direction is neutral, i. that no axial force component occurs when loaded in the circumferential direction of the joint connection.

In a further preferred embodiment, the shaft body is a hollow body, in particular of a thin-walled metal tube. Such shaft bodies are particularly material-saving and, compared with solid shaft bodies, have only a minor weight and a lower rotational moment of inertia. moderately reduced rotational (torsion) and axial (bending) moment of resistance.

If the longitudinal knurls of the longitudinally-knurled outer contour are produced by cold deformation, which is preferred, in particular by a rolling process, they have an increased strength compared to the base material.

Especially in the case of inventive shaft bodies made of metal, it is preferred that the longitudinal knurls of the longitudinally-knurled outer contour are hardened. Such longitudinal knurls furrow particularly well into the receiving openings of a hub body and are particularly suitable for thin-walled hardened hub body.

In yet another preferred embodiment, the shaft body is integrally formed, in particular without cohesive joints, whereby a particularly cost-effective and stable shaft body results.

A second aspect of the invention relates to a shaft assembly with a shaft body according to the first aspect of the invention. The shaft body has one or more sections with a longitudinally-knurled outer contour, on which one or more hub bodies are correspondingly fastened by pressing in the axial direction on the longitudinally knurled outer contours. The formation of such a shaft arrangement corresponds to the intended use of the shaft body according to the first aspect of the invention.

In a preferred embodiment of the shaft arrangement, the hub body or bodies have a receiving bore which is cylindrical at least over the major part of its axial extension and in which the respective section is received with a longitudinally contoured outer contour. Such shaft assemblies are inexpensive to manufacture, since the receiving bores of the hub body can be produced by simple manufacturing methods. In a further preferred embodiment of the shaft arrangement, the hub body or at least one of the hub body has a ratio of the mean diameter of the receiving bore of the hub body to the smallest wall thickness in the radial direction of the hub body of greater than 10, preferably greater than 15. In shaft assemblies with such "thin-walled" hub bodies The advantage of the invention come particularly clearly to bear.

Further, it is preferred that the hub body or at least one of the hub body has a receiving bore with a curved Einführfase which merges substantially seamlessly into the inner surface of the receiving bore. This further reduces the risk of abrupt Aufpresskraftstössen when joining and thus the risk of pre-damage of the hub body. Also, such an introduction phase of the

Self-centering between hub and shaft body before the actual joining process.

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 insertion chamfer, X is the axial extent starting from the receiving bore, FL is the total length of the introduction 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.

In yet another preferred embodiment of the shaft arrangement, the hub body or at least one of the hub body has a receiving bore, which has prefabricated inner knurls, which in the longitudinal knurl of the longitudinal outer contour of the knurled therein intervene in the recorded section. As a result, the positive connection between the hub body and shaft body can be intensified.

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:

Figures la-lc three different embodiments of the inventive shaft body in side view;

. Fig. 2 shows the shaft of Figure lb body when pressed on ^¬ a hub body on its longitudinal knurls to form an inventive shaft assembly;

FIG. 3 shows detail X from FIG. 2 in a second hub body for forming a shaft arrangement according to the invention; FIG. and

4 shows a third hub body for forming an inventive shaft arrangement in section.

WAYS FOR CARRYING OUT THE INVENTION

Three different embodiments of the inventive shaft body 1 are shown in the side view in the figures la-lc.

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 and on the right and left thereof each have a section 9 with a smooth outer contour. While the last-mentioned sections 9 are designed throughout as circular cylinders, the sections 2 with the longitudinally-knurled outer contour are formed differently in the three embodiments.

In the embodiment illustrated in FIG. 1 a, the longitudinally-knurled outer contour is starting from one end of the section 2 over a first partial region a of the longitudinal extent L in the periphery steplessly and steadily increasing, such that the section 2 in this first portion a has a truncated cone shape with längsgerändelter 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 truncated conical portion a of the section 2 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 equal to the outer diameter Dl of the second section b of the longitudinally interleaved section 2. In the present case, the first partial region a extends approximately over one third of the longitudinal extension L of the slow-twisted section 2.

In the embodiment illustrated in FIG. 1b, the longitudinally-knurled outer contour, starting from one end of section 2 over its entire longitudinal extension L, increases in circumference continuously and steadily, 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 here about 3 °.

In the embodiment shown in FIG. 1c, the longitudinally-knurled outer contour gradually increases in circumference, starting from one end of section 2 over its longitudinal extent L, such that section 2 in a first section a is larger than circular cylinder with longitudinally contoured outer contour with outer diameter D3 the outside diameter d of the left portion 9 is formed with the smooth outer contour and in a second portion b, which adjoins directly to the first portion a, as a circular cylinder with longitudinally knurled outer contour with an outer diameter Dl, which is greater than the outer diameter D3 of the first portion of the section 2. In the present case, the two sections a, b each extend over one half of the longitudinal extent L of the slow-twisted section 2.

Common to all three embodiments is that the longitudinal extent L of the longitudinally interleaved portion 2 is greater than two-thirds of the largest diameter Dl of the respective section 2, that the longitudinally knurled outer contour is formed by uniformly distributed over the circumference of the outer contour longitudinal knurl 4 and that the Längsrändel 4 each seen in the longitudinal direction parallel to the longitudinal axis of the respective shaft body 1 extend.

FIG. 2 shows the shaft body 1 from FIG. 1b when a hub body 1 is pressed onto its longitudinally twisted section 2 to form a shaft arrangement according to the invention. The hub body 3 is shown in section. The difference between the outer diameter d of the left cylindrical section 9 with a smooth outer contour and the inner diameter D2 of the receiving bore 6 of the hub body 3 is exaggerated.

As can be seen, the receiving bore 6 of the hub body 3 is designed as a cylindrical bore over the major part of the axial extension of the hub body 3, which merges with an insertion bevel 7 in the end face 8 of the hub body 3 on the bore side pointing in the pressing-on direction P.

In the present case, the ratio of

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. 3 shows the detail X of Fig. 2 at a second hub body, which is also for formation a shaft assembly according to the invention with one of the shaft body 1 of the figures la-lc is suitable. This hub body 3 has a cylindrical receiving bore 6 with an inner diameter D2 with 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 a is the chamfer angle (a) at the end face 8 of the hub body 3.

Fig. 4 shows a third hub body 3, which is also suitable for forming a shaft assembly according to the invention with one of the shaft body of the figures la-lc. As can be seen, the receiving bore 6 of the hub body 3 has prefabricated inner rim 10 for engaging in the longitudinal knurl 4 of the longitudinally-knurled portion 2 of one of the shaft bodies 3 of FIGS. 1 a-lc when pressed onto such a shaft body 3 form in the present case a circular cylindrical knurled inside contour over a large part of its axial extent of the hub body 3, to which a section c with a circular cylindrical smooth inner contour and then an introduction chamfer 7 adjoins on the bore side pointing in the pressing direction P.

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

Claims

1. shaft body (1), in particular of metal, with a portion (2) with a longitudinally knurled outer contour to form a hub connection between the shaft body (1) and a hub body (3) by pressing the hub body (3) in the axial direction on the longitudinally knurled Outer contour of the section (2), characterized in that the longitudinally knurled outer contour starting from one end of the section (2) at least over a partial region (a, L) of the section (2) in

Scope is infinitely or gradually formed increasingly.

2. shaft body (1) according to claim 1, characterized in that the portion (a) of the section (2) in which the longitudinally knurled outer contour is increasingly formed in the periphery, at least over a sixth, in particular over a quarter and in particular extends over one third of the longitudinal extent (L) of the section (2).

3. shaft body (1) according to one of the preceding claims, characterized in that the longitudinally knurled outer contour of the portion (2) over the entire longitudinal extension (L) of the section (2) is continuously or gradually formed in the periphery progressively.

4. shaft body (1) according to one of the preceding claims, characterized in that the longitudinally knurled outer contour of the portion (2) is a polygonal or substantially circular outer contour.

Shaft body (1) according to one of the preceding claims, characterized in that the longitudinally-knurled outer contour of the portion (2) in the region (a, L), in which it is increasingly formed in the circumference, is uniformly increasing in circumference, in particular with a pitch angle with respect to the longitudinal axis of the shaft body (1) of less than 10 °, in particular of less than 5 °.

6. shaft body (1) according to one of vorange ^¬ Henden claims, characterized in that the longitudinal extent (L) of the section (2) is greater than the Hälf ^¬ te, in particular greater than two-thirds of the largest diameter (Dl) of its längsgerändelten outer contour ,

7. shaft body (1) according to one of the preceding claims, characterized in that the longitudinally knurled outer contour of the portion (2) by evenly over the circumference of the outer contour distributed longitudinal knurl (4) is formed.

8. shaft body (1) according to one of vorange ^¬ Henden claims, characterized in that the longitudinal knurls (4) of the längsgerändelten outer contour of the portion (2) in the area (a, L), in which this off ^¬ senkontur within the scope is increasingly formed, increase in width with increasing extent of the longitudinally knurled outer contour.

9. shaft body (1) according to one of claims 1 to 7, characterized in that the Längsrändel (4) of the longitudinally knurled outer contour of the portion (2) in the region (a, L), in which this outer contour is increasingly formed in the circumference, a uniform width on iron.

10. Shaft body (1) according to one of the preceding claims, characterized in that the longitudinal knurls (4) of the longitudinally knurled outer contour of the portion (2) each seen in the longitudinal direction parallel to the longitudinal axis of the shaft body (1).

11. shaft body (1) according to one of the preceding claims, characterized in that the shaft body (1) is a hollow body, in particular of a thin-walled metal tube.

12. shaft body (1) according to one of the preceding claims, characterized in that the longitudinal knurl (4) of the longitudinally knurled outer contour of the Ab- Section (2) are produced by cold deformation, in particular by a rolling process.

13. Shaft body (1) according to one of the preceding claims, characterized in that the shaft body (1) is made of metal and the longitudinal knurls (4) of the longitudinally knurled outer contour of the portion (2) are hardened.

14. shaft body (1) according to one of the preceding claims, characterized in that the shaft body (1) is integrally formed.

15 shaft assembly comprising a shaft body (1) according to one of the preceding claims with one or more sections (2) with a longitudinally ^¬ delten outer contour and one or more in the axial direction on the longitudinally knurled outer contours of the sections (2) pressed hub bodies (3).

16 shaft assembly according to claim 15, characterized in that the or the hub body (3) has a cylindrical at least over the major part of its axial extent receiving bore (6), in which each of the respective section (2) is taken with längsgerändelter outer contour.

17. Shaft arrangement according to one of claims 15 to 16, characterized in that the hub body

(3) or at least one of the hub bodies (3) has a ratio of the mean 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) of greater than 10, in particular greater than 15 has.

18. Shaft arrangement according to one of claims 15 to 17, characterized in that the hub body (3) or at least one of the hub body (3) has a receiving bore (6) with a curved Einführfase (7), which is substantially seamless in the inner surface (7). 5) of the receiving bore (6) passes.

19. shaft arrangement (5) according to claim 18, wherein the introduction bevel (7), starting from the inner surface (5) of the receiving bore (6) according to 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 α is the chamfer angle (A) on the end face (8) of the hub body (3).

20. Shaft arrangement according to one of claims 15 to 19, characterized in that the hub body (3) or at least one of the hub body (3) has a receiving bore (6) which has prefabricated inner knurl (10) which in the longitudinal knurl (4). engage the longitudinally knurled outer contour of the recorded therein section (2).