DE102015110679B4 - Method for compensating tolerances between a stator and a rotor of a phase adjuster for an adjustable camshaft - Google Patents

Abstract

Method for compensating for tolerances between a stator (10) and a rotor (11) of a phase adjuster (1) for an adjustable camshaft (12), the stator (10) having an outer shaft (13) and the rotor (11) having an Inner shaft (14) of the adjustable camshaft (12) is connected, so that when the rotor (11) rotates in the stator (10), the phase position of the inner shaft (14) is adjusted relative to the phase position of the outer shaft (13), and a gap (5 ) is formed between at least one sliding surface (15) on the stator (10) and at least one sliding surface (16) on the rotor (11), and wherein the method comprises at least the following steps: - Coating at least one of the sliding surfaces (15, 16) with a removable coating (17), - assembling the phase adjuster (1) including the joining of the rotor (11) in the stator (10), - putting the phase adjuster (1) into operation by rotating the rotor (11) in the stator (10) and adjusting of the gap (5) between the stator (10) and the Rotor (11) by means of abrasion of at least part of the thickness of the coating (17), the coating (17) being partially or completely removed by wear caused in a controlled manner if there is a tolerance deviation.

Description

The invention relates to a method for compensating tolerances between a stator and a rotor of a phaser for an adjustable camshaft, the stator being connected to an outer shaft and the rotor to an inner shaft of the adjustable camshaft, so that when the rotor rotates in the stator, the phase position of the Inner shaft is adjusted relative to the phase position of the outer shaft, and wherein a gap is formed between at least one sliding surface on the stator and at least one sliding surface on the rotor.

STATE OF THE ART

For example, from the DE 11 2012 001 009 T5 a method for compensating tolerances between a stator and a rotor of a phase adjuster is known, in which a torsion drive mechanism is provided which allows the adjustment of the vertical position and axial alignment of the inner to the outer camshaft, while a torsionally rigid coupling between the camshaft adjuster and the inner or outer camshaft of the concentric camshaft is maintained. The torsion drive mechanism is formed either from a flexible shaft coupling, a transversely split driven wheel, a transversely split toothed ring gear, a transverse pin toothed wheel or a pin and slot combination drive. Disadvantageously, the torsion drive mechanism is complex and requires additional installation space.

WO 2011/133 452 A2 proposes the use of a flexible coupling element between the phase adjuster and the camshaft, which is shown differently with different exemplary embodiments. for example, the coupling forms a flexible disk or a flexible ring, whereby misalignment can be compensated for. Disadvantageously, the flexible coupling requires another component, and the flexible connection between the rotor or stator of the phaser and the inner shaft or the outer shaft can cause vibrations to build up in the overall connection between the camshaft and the phaser.

The stator is mostly designed like a pot and mostly has a first cover element and a second cover element. The rotor, which can be rotated relative to the stator, is received between the cover elements. If the rotor is fastened to the inner shaft, for example with a fastening means such as a screw, and the stator is brought into connection with the outer shaft, misalignment of the inner shaft relative to the outer shaft is also transferred to the position of the rotor within the stator of the phase adjuster. An addition of several tolerances, which are formed in particular by the connection points between the rotor and the inner shaft and between the stator and the outer shaft, but also by shape and position tolerances of the other components of the phase adjuster to one another, can lead to malfunctions and even blocking of the phase adjuster, so that the rotor is no longer freely rotatable in the stator. If the gap between the sliding surfaces of the rotor and the stator is chosen to be too large, the leakage flow of the oil with which the phase adjuster is operated is too great. In particular, it should be possible to form essentially oil-tight pressure spaces between vanes formed on the rotor and stators formed on the stator in order not to negatively influence the efficiency of the phase adjuster. If the gap is selected too large, the leakage flow of the oil between the rotor and stator is too large; if the gap is selected too small, the problem of jamming or blocking of the rotor in the stator, described above, arises.

DISCLOSURE OF THE INVENTION

The object of the invention is to develop a method for compensating for tolerances between a stator and a rotor of a phase adjuster arranged on an adjustable camshaft, which method is simple and requires no additional components if possible. Furthermore, the object of the invention relates to the provision of a phase adjuster with easily balanced tolerances between the stator and the rotor.

This object is achieved by a method with the features of claim 1. Advantageous further developments of the invention are given in the dependent claims.

The invention includes the technical teaching that the method has at least the following steps: coating at least one of the sliding surfaces with a coating that can be removed; Assembling the phaser comprising joining the rotor in the stator; Commissioning of the phase adjuster by turning the rotor in the stator and adjusting the gap between the stator and the rotor by means of abrasion of at least a partial thickness of the coating.

The method according to the invention enables tolerances between a stator and a rotor of a phase adjuster to be compensated for in a simple manner, with the method according to the invention enabling play-free running between the rotor and the stator. In the event of deviations in shape and position between the stator and the rotor, the remaining thickness of the remaining after the removal occurs during the initial start-up of the phase adjuster Coating in such a way that the rotor in the stator just does not block and can rotate freely. The method according to the invention does not require that deviations in shape and position of the rotor in the stator in the arrangement on the inner shaft and on the outer shaft are corrected, but rather the desired gap that is as small as possible is set by itself so that the phase adjuster after the setting of the Gap enables the same functional effect as a phase adjuster with ideally dimensionally accurate rotor and stator.

If the camshaft is put into operation with the phase adjuster, the coating is partially or completely removed, at least if there is a tolerance deviation, according to the invention by wear which is caused in a controlled manner. This is because at least the partial thickness of the coating is removed until an ideal gap is formed and until the coating is no longer abraded by the opposite sliding surface or coating on the opposite surface.

It is particularly advantageous if the coating is removed by an abrasion process by means of the sliding surface opposite the coating when the camshaft is put into operation. The opposite surface can also be the surface of a further coating. The mechanically induced removal of the coating occurs primarily through an abrasion process and thus through wear. For this, the coating has a lower and, in particular, significantly lower hardness than the components of the phase adjuster, that is to say, for example, the material hardness of the rotor or the stator.

According to an advantageous embodiment, the coating is formed from a lubricating varnish or from another material that can be applied. The coating, for example the anti-friction varnish, is applied over the entire surface of the sliding surface of the component, with the coating advantageously also being able to be applied only to a limited extent to partial areas, in particular locally limited on the sliding surface that runs against the opposite sliding surface and the wear-based removal can occur . Thus, the stator does not have to be coated completely on the inside and the rotor does not have to be coated completely on the outside, and the coating is limited to partial areas which are used for later sliding movement on the opposite surface. For example, several partial areas can be provided, which are formed punctually or at least locally limited on segments of the, for example, circular sliding surface by the coating on the stator or the rotor.

The method according to the invention provides for the start-up of the phaser by activating the camshaft in order to at least partially remove the coating and to form the axial play, and the start-up of the camshaft, for example, is only carried out in the arrangement on a cylinder head of an internal combustion engine, i.e. in the later operating environment. For example, the coating can be removed by conventionally starting up the camshaft or a camshaft module in which the camshaft is received. Alternatively, the phase adjuster will also be put into operation with the camshaft on an internal combustion engine on a run-in stand before the actual start-up, especially if coating materials are used that should not later enter the internal combustion engine's oil circuit, although it is also conceivable to use a coating material to be selected that can be present in the oil circuit without this causing damage. However, the coating is advantageously formed by a substance which does not cause any damage due to the solid solution in the oil when an internal combustion engine is in operation. The removed components of the coating, which are produced as extremely fine particles, are then separated out, for example, via filter systems in the internal combustion engine.

Figure list

• 1 eine schematische Ansicht eines Phasenstellers in Anordnung an einer verstellbaren Nockenwelle mit idealisierter Lage- und Maßgenauigkeit,
• 2 ein Phasensteller in Anordnung an einer verstellbaren Nockenwelle mit einer Desaxierung des Rotors auf der Innenwelle,
• 3 ein Phasensteller mit einer Beschichtung auf der Innenseite des Stators zur Ausführung des erfindungsgemäßen Verfahrens, und
• 4 ein Phasensteller in Anordnung an einer Nockenwelle gemäß 3, wobei eine Beschichtung auf dem Rotor des Phasenstellers aufgebracht ist.

Further measures improving the invention are shown in more detail below together with the description of an advantageous exemplary embodiment of the invention with reference to the figures. It shows:

• 1 a schematic view of a phase adjuster arranged on an adjustable camshaft with idealized positional and dimensional accuracy,
• 2 a phase adjuster arranged on an adjustable camshaft with a de-axing of the rotor on the inner shaft,
• 3 a phase adjuster with a coating on the inside of the stator for carrying out the method according to the invention, and
• 4th a phaser arranged on a camshaft according to FIG 3 , wherein a coating is applied to the rotor of the phaser.

The 1 and 2 each show a phase adjuster 1 in arrangement on an adjustable camshaft 12th according to the state of the art. In 1 is the phaser 1 shown with an idealized structure, and 2 shows the phaser 1 with dimensional deviations of the components in the position to one another, so that the inventive A method to compensate for the occurring tolerances is used to correct the dimensional deviations shown and the associated positional errors for the actual function, ie to render them harmless without correcting the actual geometric positional errors, for example between rotor and stator.

The phaser 1 and the adjustable camshaft 12th are shown schematically simplified, and the phase adjuster 1 has a stator 10 and a rotor 11 on. The stator 10 is constructed as an example with a first cover element 20th and a second cover element 21 , and between the cover element 20th and 21 there is an intermediate element 22nd , which can also be formed in one piece with the first cover element 20th or with the second cover element 21 .

The adjustable camshaft 12th has an outer shaft 13 and an inner shaft 14th on, and the outer shaft 13 and the inner shaft 14th as well as the stator 10 and the rotor 11 are around a common longitudinal axis 18th rotatable. The arrangement of the stator 10 on the outer shaft 13 is shown in simplified form about the first cover element 20th . The connection between the rotor 11 and the inner shaft 14th has a fastener 19th on, and the fastener 19th is designed, for example, as a screw element.

A comparative consideration of the 1 and 2 of the prior art shows that by a simple dimensional deviation of the end face 23 the inner shaft 14th already a considerable positional deviation of the rotor 11 in the stator 10 The result is. Becomes the phaser 1 put into operation, it either only functions to a limited extent or even blocks it completely. The restricted function lies in the deviation of the gap 5 who is in 1 idealized and is therefore the same everywhere and in 2 at the point shown, for example, by the positional deviation of the rotor 11 in the stator 10 can lead to a blockage.

The stator 10 has sliding surfaces on the inside 15th on, and the rotor 11 has sliding surfaces on the outside 16 on. The sliding surfaces 15th and 16 run while the phaser is in operation 1 on each other, and between the sliding surfaces 15th and 16 is the gap 5 required to allow the sliding surfaces to slide off when lubricated with oil 15th and 16 allow each other. Is the gap 5 does not exist and the rotor jams 11 for example only at one point or at opposite points in the stator 10 , the phase adjuster blocks 1 .

3 shows a first embodiment of the phaser 1 with a coating 17th on the inside sliding surfaces 15th on the stator 10 . This is where the rotor is located 11 in an arrangement on the inner shaft 14th , fastened with the fastener 19th , with the rotor 11 has a positional error. Due to the applied coating 17th on the inside sliding surface 15th of the stator 10 the rotor works 11 when commissioning the phase adjuster 1 into the coating 17th one by the coating 17th Abrasive over at least a partial thickness due to the movement of the rotor 11 Will get removed. As a result, there is a gap 5 one that includes a minimal gap air, so that despite the positional deviation of the rotor 11 in the stator 10 trouble-free operation of the phase setter 1 he follows. The necessary removal of part or all of the thickness of the coating 17th takes place automatically, since the coating is removed during commissioning 17th is carried out with exactly the partial thickness until the required gap 5 arises.

The stator 10 has a first cover element 20th and a second cover element 21 on, and the coating 17th is an example on the inner sliding surface 15th of the two cover elements 20th and 21 applied, ie that the stator 10 with one the receiving space for the rotor 11 reducing allowance is mounted.

4th shows in modification of 3 an embodiment in which the coating 17th on the sliding surfaces 16 of the rotor 11 is applied, ie the rotor 11 is mounted with an allowance. The sliding surfaces 16 point to the opposite inner surfaces of the stator 10 that according to 3 are coated. Of course, there is also the possibility of combining the exemplary embodiments of 3 and 4th a coating of both the sliding surfaces 15th on the stator 10 as well as the sliding surfaces 16 on the rotor 11 to be provided.

The material removed from the coating 17th is in the oil of the phase adjuster 1 transported away. The removal of the abrasively removed coating 17th enables subsequently functionally reliable operation of the phase setter 1 .

The coatings shown 17th on the sliding surface 15th on the stator 10 according to 3 and on the sliding surface 16 of the rotor 11 according to 4th are only possible exemplary designs for the application of a coating 17th . In the context of the invention, there is also the possibility of using the intermediate element, for example 22nd of the stator 10 to be provided with a coating on the inside or the rotor 11 has an outside coating. Such a coating that can be removed, in particular compensates for a radial run, is required, for example, in the case of a de-axed stator arrangement 10 on the outer shaft 13 or the rotor 11 on the inner shaft 14th .

The embodiment of the invention is not limited to the advantageous exemplary embodiments specified above. Rather, a number of different variants are conceivable which make use of the solution shown even in the case of fundamentally different designs. All of the features and / or advantages arising from the claims, the description or the drawings, including structural details or spatial arrangements, can be essential to the invention both individually and in a wide variety of combinations.

List of reference symbols

1

Phase adjuster

5

gap

10

stator

11

rotor

12th

adjustable camshaft

15th

Outer shaft

14th

Inner shaft

15th

Sliding surface (on the stator)

16

Sliding surface (on rotor)

17th

Coating

18th

Longitudinal axis

19th

Fasteners

20th

first cover element

21

second cover element

22nd

Intermediate element

23

Face

Claims (5)

Method for compensating tolerances between a stator (10) and a rotor (11) of a phase adjuster (1) for an adjustable camshaft (12), the stator (10) having an outer shaft (13) and the rotor (11) having an Inner shaft (14) of the adjustable camshaft (12) is connected, so that when the rotor (11) rotates in the stator (10), the phase position of the inner shaft (14) is adjusted relative to the phase position of the outer shaft (13), and a gap (5 ) is formed between at least one sliding surface (15) on the stator (10) and at least one sliding surface (16) on the rotor (11), and wherein the method comprises at least the following steps: - Coating at least one of the sliding surfaces (15, 16) with a removable coating (17), - Assembling the phase adjuster (1) including the joining of the rotor (11) in the stator (10), - Commissioning of the phase adjuster (1) by turning the rotor (11) in the stator (10) and - Setting the gap (5) between the stator (10) and the rotor (11) by means of abrasion of at least a partial thickness of the coating (17), wherein - If there is a tolerance deviation, the coating (17) is partially or completely removed by wear which is caused in a controlled manner. Procedure according to Claim 1 , characterized in that the coating (17) is removed by an abrasion process by means of the sliding surface (15, 16) opposite the coating (17) when the camshaft (12) is put into operation. Procedure according to Claim 1 or 2 , characterized in that the coating (17) is applied to the sliding surface (15, 16) from an applicable lacquer, in particular from a lubricating lacquer. Method according to one of the Claims 1 to 3 , characterized in that the coating (17) is applied limited to a partial area of the stator (10) and / or the rotor (11), in particular locally limited to at least one of the sliding surfaces (15, 16). Method according to one of the preceding claims, characterized in that the phase adjuster (1) is started up when the camshaft (12) is started up in an arrangement on a cylinder head of an internal combustion engine.

Images