DE102016221197A1 - Camshaft adjuster with tension-optimized threaded bandage for a non-rotatable connection to a camshaft - Google Patents

Abstract

The invention relates to a camshaft adjuster (1) for an internal combustion engine, having a rotational component (3) rotatably mounted about a rotation axis (2) and a camshaft for mounting the rotation component (3) in an axial direction of the rotation component (3) Rotary axis (2) penetrating screw (4), wherein the screw (4) with a contact surface (5) on a counter-bearing surface (6) on the rotary member (3) is supported, wherein at least one of the two surfaces (5, 6) obliquely to a radial direction of the axis of rotation (2) is designed to extend.

Description

The invention relates to a camshaft adjuster for an internal combustion engine of a motor vehicle, such as a car, truck, bus or other commercial vehicle, with a rotary member rotatably mounted about an axis of rotation and a prepared for mounting the rotary member on a camshaft, penetrating the rotary member in an axial direction of the axis of rotation Screw, wherein the screw is supported with a contact surface on a counter-contact surface in the rotary member. The phaser is preferably configured as a hydraulic phaser, more preferably as a vane-type hydraulic phaser, or, preferably, as an electric phaser.

Generic prior art is already well known. The DE 10 2008 032 031 A1 discloses a camshaft adjuster with at least one working chambers laterally limiting, applied to a stator and / or a rotor, sealing cover. The sealing cover, the stator and / or the rotor have a convex, concave or conical contact surface and the sealing cover is elastically deformable by the attachment over the contact surface, so that it by the elastic deformation with an increased sealing force on the stator and / or the rotor is applied.

Further prior art is known from DE 10 2014 209 003 A1 known.

In the embodiments known from the prior art, however, it has proved to be disadvantageous that the fastening forces applied to the rotor component as well as the operating forces applied during operation can lead to an involuntary deformation of the rotary component. In particular, the rotor component, for example, a rotor of the camshaft adjuster, due to the introduced by the fastening voltages wear relatively strong or even jammed relative to a stator of the camshaft adjuster. Other components, such as return springs or the like are affected by these stresses during operation and experience increased fretting wear.

It is therefore the object of the present invention to remedy these disadvantages known from the prior art and in particular to provide a camshaft adjuster which is to be mountable with the lowest possible voltage input.

This is inventively achieved in that at least one of the two surfaces (from the totality of the contact surface and the counter-contact surface) is formed running obliquely to a radial direction of the axis of rotation.

By such an oblique / conical shape of at least one of the two surfaces, the rotational component is significantly less deformed when screwing the screw in the camshaft and thus relatively less displaced relative to the other components of the camshaft adjuster. A significantly lower wear is the result. In particular, an axial expansion of the respective rotor component (for example rotor, adapter for spring suspension or end cover in the region of a thrust bearing) is reliably avoided by its deformation under the biasing force of the screw, so that jamming, in particular that on a thrust bearing, is no longer possible. The stresses in the respective rotor component are further reduced by optimizing the force flow in the rotor components from the screw head to the camshaft.

Further advantageous embodiments are claimed in the subclaims and explained in more detail below.

The screw is advantageously designed as a central valve or as a central screw.

It is particularly advantageous if the contact surface and / or the counter-contact surface are concave, i. viewed in the axial direction in the radial direction inwardly away from the other surface, extending or convex, i. viewed in the axial direction in the radial direction inwardly toward the other surface extends.

If the abutment surface is planar (i.e., running (straight) in a radial plane / in the radial direction with respect to the axis of rotation) and the counter abutment surface is again inclined, preferably concave, then a rotor with a particularly deformation resistance is implemented. In particular, bears the contact surface of the screw, which is preferably formed on a screw head of the screw, before screwing predominantly on the outer diameter. After screwing the screw head is axially elastically deformed by the rotary member as well as full surface on the concave counter-surface / rotor surface. An edge support on the inner diameter of the screw head and thus also the deformation of the rotor on the thrust bearing are thereby avoided. The flow of forces takes place above the inner step profile in the components. As a result, a full support of the biasing force is achieved on the camshaft and reduces the bending of the cross section under the Schraubenvorspannkraft and even completely avoided.

If the concave surface on the screw head, ie the contact surface of the screw is concave, and the counter-contact surface is flat, such a low-stress bond is theoretically possible as well.

It is also possible in principle to provide a combination of a concave and a convex surface on the screw or on the rotary component. For example, a convex surface could be provided by the abutment surface on the screw to reinforce the screw head or to reduce the stresses in the screw head under the action of the biasing force. A concave contact surface would then be on the rotating member, i. in the form of the counter-contact surface, implemented for stress optimization and deformation reduction of these parts in the region of a thrust bearing and to avoid jamming under the biasing force of the central valve / the screw after the motor assembly.

Furthermore, it is advantageous if the counter-contact surface runs continuously obliquely in the circumferential direction, preferably concave. As a result, the counter-contact surface is particularly easy to produce.

If the counter-contact surface has a continuous (uniform) oblique, preferably concave, extension / configuration in the radial direction, the counter-contact surface is particularly simple.

It is also advantageous if the rotational component either itself directly as a rotor of the camshaft adjuster or as an adapter for a spring suspension, which adapter is rotatably connected in operation with the rotor is formed. In both cases, the camshaft adjuster is then preferably designed as a hydraulic camshaft adjuster.

It is again expedient if the rotary component is designed as a cover / end wheel to be used preferably in an electric camshaft adjuster, in particular in an adjusting gear in the electric camshaft adjuster.

In other words, in order to reduce the problem, voltages and deformations in the region of the screw connection for mounting the camshaft adjuster on a camshaft to solve, according to the invention at least one concave / oblique surface (contact surface and / or counter-contact surface) is used.

The invention will now be explained with reference to figures, in which context also different embodiments are shown.

• 1 eine Längsschnittdarstellung eines erfindungsgemäßen Nockenwellenverstellers nach einem ersten Ausführungsbeispiel, wobei eine als Zentralventil ausgestaltete Schraube vorgesehen ist, einen mit einem Rotor drehfest verbundenen Adapter mit einer Nockenwelle im Betrieb zu verbinden,
• 2 eine Detailansicht eines in 1 mit „II“ gekennzeichneten Kontaktbereiches zwischen einer an dem Adapter vorgesehenen Gegenanlagefläche und einer an der Schraube ausgebildeten Anlagefläche,
• 3 eine Vorderansicht des Nockenwellenverstellers nach 1,
• 4 eine Längsschnittdarstellung des in dem Nockenwellenversteller der 1 und 2 eingesetzten Adapters,
• 5 eine Vorderansicht des Adapters nach 4,
• 6 eine Längsschnittdarstellung eines für einen Nockenwellenversteller nach einem zweiten Ausführungsbeispiel vorbereiteten Rotors, wobei eine Gegenanlagefläche zur Abstützung der Schraube nun unmittelbar an dem Rotor ausgebildet ist,
• 7 eine Vorderansicht des Rotors nach 6,
• 8 eine Längsschnittdarstellung eines Nockenwellenverstellers nach einem weiteren dritten Ausführungsbeispiel, wobei die die Schraube abstützende Gegenanlagefläche an einem Abschlussdeckel ausgebildet ist,
• 9 eine Detailansicht eines in 8 mit „IX“ gekennzeichneten Kontaktbereiches zwischen der Anlagefläche der Schraube und der Gegenanlagefläche seitens des Abschlussdeckels,
• 10 eine Vorderansicht des Nockenwellenverstellers nach 8,
• 11 eine Längsschnittdarstellung des Abschlussdeckels, wie er in 8 eingesetzt ist, sowie
• 12 eine Vorderansicht des Abschlussdeckels der 11.

Show it:

• 1 a longitudinal sectional view of a camshaft adjuster according to the invention according to a first embodiment, wherein designed as a central valve screw is provided to connect a rotatably connected to a rotor adapter with a camshaft in operation,
• 2 a detailed view of an in 1 "contact area" marked with "II" between a countercontact surface provided on the adapter and a contact surface formed on the screw,
• 3 a front view of the camshaft adjuster after 1 .
• 4 a longitudinal sectional view of the in the camshaft adjuster the 1 and 2 inserted adapter,
• 5 a front view of the adapter after 4 .
• 6 a longitudinal sectional view of a prepared for a camshaft adjuster according to a second embodiment rotor, wherein a counter-contact surface for supporting the screw is now formed directly on the rotor,
• 7 a front view of the rotor after 6 .
• 8th a longitudinal sectional view of a camshaft adjuster according to a further third embodiment, wherein the screw supporting the counter-bearing surface is formed on a cover plate,
• 9 a detailed view of an in 8th with "IX" marked contact area between the contact surface of the screw and the counter-contact surface on the part of the end cover,
• 10 a front view of the camshaft adjuster after 8th .
• 11 a longitudinal sectional view of the end cover, as in 8th is used, as well
• 12 a front view of the end cap of the 11 ,

The figures are merely schematic in nature and are for the sole purpose of understanding the invention. The same elements are provided with the same reference numerals.

In the 1 to 5 is a first embodiment of a camshaft adjuster according to the invention 1 shown. The camshaft adjuster 1 is in its basic structure in 1 clearly visible. The camshaft adjuster 1 serves in its operation for adjusting a relative phase position of a 1 the sake of clarity not shown camshaft to a crankshaft of an internal combustion engine.

The camshaft adjuster 1 This first embodiment is as a hydraulic camshaft adjuster 1 of the wing cell type. The camshaft adjuster 1 Therefore, in known manner, a rotor 7 up, relative to a stator 8th around a rotation axis 2 is rotatable. Rotationally with the rotor 7 is a rotary component 3 in the form of an adapter 9 , connected. The rotary component 3 / the adapter 9 is with a return spring 10 further connected in the form of a coil spring. The return spring 10 serves to reset the rotor 7 relative to the stator 8th in a certain initial rotational position. The return spring 10 is for it with a first end firmly with the adapter 9 with a second end opposite the first end fixed to the stator 8th connected. The return spring 10 is under bias of the rotor 7 in the direction of rotation in the output rotational position relative to the stator 8th clamped.

For fastening the camshaft adjuster 1 namely the rotor 7 , on the camshaft is a screw 4 , The screw 4 is here designed in the form of a central valve, thus includes in addition to the function of the pure screw on the camshaft that of a valve for controlling a plurality of not shown here for clarity sake working chambers between the rotor 7 and the stator 8th ,

According to the invention, for optimized installation / support of the screw 4 from the rotor component 3 , is on the screw 4 a contact surface 5 designed, which at a Gegenanlagefläche 6 on the rotor component 3 / Adapter 9 is applied. The counter-investment area 6 runs (considered in the unloaded state, in which the screw 4 the rotor component 3 not yet fully attached to the camshaft) obliquely to a radial direction of a rotation axis 2 of the camshaft adjuster 1 / of the rotor component 3 , In particular, one speaks here of a concave counter-surface 6 because it runs in the radial direction so that it increases in the radial direction inwards increasingly from the contact surface 5 spaced. The contact surface 5 is again on a screw head 11 the screw 4 arranged. The contact surface 5 from the screw head 11 , in the attached state at the counter contact surface 6 to the adapter 9 is pressed, is just configured, ie this contact surface 5 extends only in a radial direction of the axis of rotation 2 straight to the outside.

As then again in the detail view 2 it can be seen, is the counter-investment surface 6 configured concave / obliquely so that a gap 12 between the screw head 11 and the adapter 9 in the unloaded state / unfastened state extended inwards. An angle α, the inclination of the counter-bearing surface 6 to an imaginary vertical / radial direction of the axis of rotation 2 extending line defined, is preferably between 0.1 ° and 1 °, more preferably about 0.2 °.

In 4 is good to see that the counter-investment surface 6 Part of a radial shoulder 13 of the rotary component 3 / Adapters 9 is. It can also be seen that the inclination of the counter bearing surface 6 remains the same in the radial direction. In a radial outer side, the counter-contact surface goes 6 finally in an outlet area 14 over in the assembled state outside the screw head 11 is arranged and in turn extends straight only in the radial direction.

In principle it should be mentioned that it is also possible to use the screw head 11 , instead of with the flat surface / contact surface 5 , also with an oblique, preferably with a convex, alternatively with a concave surface / contact surface 5 embody. In this case, a convex surface is in turn meant a surface which extends in the radial direction so as to extend radially outward from the other surface, here the counter-abutment surface 6 , spaced. The counter-investment area 6 would then preferably just run.

In connection with the 6 and 7 is a second embodiment of the camshaft adjuster according to the invention 1 illustrated, wherein the rotary member 3 at which the oblique counter investment surface 6 for supporting the screw head 11 is formed, directly on the rotor 7 is trained. The remaining designs as well as interactions with the screw 4 This second embodiment corresponds to those of the first embodiment.

In conjunction with the 8th to 12 is a third embodiment of the camshaft adjuster according to the invention 1 shown. Here is the camshaft adjuster 1 no more than hydraulic camshaft adjuster 1 but as an electric phaser 1 executed. A finishing cover 15 forms the rotary component 3 out, in turn, rotatably with the camshaft now shown 16 connected is. As in particular in 9 such as 11 to recognize, has the end cap 15 the oblique / oblique extending counter-investment surface 6 for supporting the screw head 11 on. The end cover 15 is preferably arranged in the region of a thrust bearing. Also, the camshaft adjuster points 1 an adjusting gear on.

It is particularly advantageous if the counter bearing surface 6 is produced in the respective embodiment in a sintering process in such a sintering tool that they already in the original molding of the rotary component 3 is fully formed. For this purpose, the respective rotational component 3 in the form of the rotor 7 , the adapter 9 or the end cap 15 each made of a sintered material. For example, the counter-investment surface 6 then be formed by a simple overpressing.

The inclination of the counter-contact surface 6 , more preferably also the contact surface 5 , It can be seen in particular that this is preferably concave and not convex over the entire surface. The camshaft adjuster 1 can thus either as a hydraulic camshaft adjuster 1 be executed, in which case the counter-contact surface on the rotor 7 yourself or on the adapter 9 intended for spring suspension, or as an electric camshaft adjuster 1 be formed, in which case a cover 15 is provided in an adjusting the camshaft adjuster.

The inclination results in a total of a smaller dispersion of Anschraubmomentes during engine assembly of the camshaft adjuster 1 Furthermore, a reduction of the influence of the preload force on the functional risks after the motor assembly (clamps, leakage, component stresses and / or deformations), a guarantee of the quality of the screw connection and a reduction of the reject rate after the motor assembly.

LIST OF REFERENCE NUMBERS

1

Phaser

2

axis of rotation

3

rotating member

4

screw

5

contact surface

6

Anvil surface

7

rotor

8th

stator

9

adapter

10

Return spring

11

screw head

12

gap

13

shoulder

14

outdoor area

15

End cover

16

camshaft

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008032031 A1 [0002]
• DE 102014209003 A1 [0003]

Claims (4)

Camshaft adjuster (1) for an internal combustion engine, with a rotation member (3) rotatably disposed about a rotation axis (2) and a camshaft for mounting the rotation member (3), the rotation member (3) in an axial direction of the rotation axis (2) penetrating screw (4), wherein the screw (4) with a bearing surface (5) on a counter-bearing surface (6) on the rotary member (3) is supported, characterized in that at least one of the two surfaces (5, 6) obliquely to a Radial direction of the axis of rotation (2) is designed to extend. Camshaft adjuster (1) to Claim 1 , characterized in that the abutment surface (5) is planar and the counter abutment surface (6) is formed obliquely. Camshaft adjuster (1) to Claim 1 or 2 , characterized in that the counter abutment surface (6) extends continuously obliquely in the circumferential direction. Camshaft adjuster (1) according to one of Claims 1 to 3 , characterized in that the counter-bearing surface (6) seen in the radial direction has a continuous oblique extent.

Images