DE102013203951A1 - Control valve of a camshaft adjuster - Google Patents

Abstract

Proposed a control valve (1) of a camshaft adjuster, which has a designed as a screw multi-part housing (2).

Description

Field of the invention

The invention relates to a control valve of a camshaft adjuster.

Background of the invention

Camshaft adjusters are used in internal combustion engines to vary the timing of the combustion chamber valves in order to make the phase relation between a crankshaft and a camshaft in a defined angular range, between a maximum early and a maximum late position, variable. Adjusting the timing to the current load and speed reduces fuel consumption and emissions. For this purpose, camshaft adjuster are integrated into a drive train, via which a torque is transmitted from the crankshaft to the camshaft. This drive train may be formed for example as a belt, chain or gear drive.

In a hydraulic camshaft adjuster, the output element and the drive element form one or more pairs of mutually acting pressure chambers, which can be acted upon by hydraulic fluid. The drive element and the output element are arranged coaxially. By filling and emptying individual pressure chambers, a relative movement between the drive element and the output element is generated. The rotationally acting on between the drive element and the output element spring urges the drive element relative to the output element in an advantageous direction. This advantage direction can be the same or opposite to the direction of rotation.

One type of hydraulic phaser is the vane phaser. The vane cell adjuster comprises a stator, a rotor and a drive wheel with an external toothing. The rotor is designed as a driven element usually rotatably connected to the camshaft. The drive element includes the stator and the drive wheel. The stator and the drive wheel are rotatably connected to each other or alternatively formed integrally with each other. The rotor is coaxial with the stator and located inside the stator. The rotor and the stator are characterized by their, radially extending wings, oppositely acting oil chambers, which are acted upon by oil pressure and allow relative rotation between the stator and the rotor. The wings are either formed integrally with the rotor or the stator or arranged as "inserted wings" in designated grooves of the rotor or the stator. Furthermore, the vane cell adjusters have various sealing lids. The stator and the sealing lids are secured together via several screw connections.

Another type of hydraulic phaser is the axial piston phaser. Here, a displacement element is axially displaced via oil pressure, which generates a helical gear teeth relative rotation between a drive element and an output element.

The hydraulic camshaft phaser control valves control the flow of hydraulic fluid between the phaser and the oil pump or reservoir.

The control valve has a hollow cylindrical housing and a rotationally symmetrical control piston. Within the housing of the control valve, the control piston is arranged. The control piston is movable in the axial direction and guided by the housing. Thus, the control piston can be positioned to the housing in any axial position. The positioning is carried out by an electromagnet, which contacted with its actuating pin one end of the control piston and can move the control piston. A spring ensures the contact between the control piston and the actuating pin. By the axial positioning of the control piston, the various ports of the control valve are hydraulically connected to each other or separated from each other and can communicate with each other or not. For guiding the hydraulic fluid between the terminals are control piston and housing with openings, for. B. grooves and / or holes provided. The control piston has control edges which, together with the edges of the openings of the housing, control the flow. The control edges themselves are the edges of the respective opening, z. B. grooves, the control piston. To control the flow, the edges of the openings of the housing and the control edges are positioned to each other such that an opening of the housing with an opening of the control piston as far as possible faces and forms, over the axial positionability of the control piston, variable flow area for the hydraulic medium.

A control valve designed as a central valve is arranged coaxially to the axis of symmetry or rotation of the camshaft adjuster or the camshaft. In addition, the central valve is placed inside the camshaft adjuster, ie central valve and camshaft adjuster build on each other in the radial direction. Optionally, the camshaft can be arranged between the camshaft adjuster and the central valve. The housing of the central valve may be formed as a central screw, whereby the camshaft adjuster is braced against rotation with the camshaft. Of the Electromagnet is arranged as a central magnet largely aligned with the central valve and usually fixed to the frame, in particular on the cylinder head arranged.

Alternatively, a control valve with an electromagnet fixedly secured thereto may be disposed at any position in the hydraulic fluid gallery, outside the phaser and the camshaft, and control the flow of hydraulic fluid.

Summary of the invention

The object of the invention is to provide a control valve of a camshaft adjuster, which allows a more economical production.

According to the invention, this object is solved by the features of claim 1.

This object is achieved by a control valve of a camshaft adjuster, wherein the control valve for controlling the camshaft adjuster is flowed through by the hydraulic fluid and the control valve has an inflow port, a plurality of working ports and a tank port, wherein the control valve has a screw-shaped housing with a cylindrical cavity in which Control piston is axially bewegbar guided, wherein the housing designed as a screw is formed in several parts, which has a threaded body and a sleeve, wherein the threaded body is connected to the threaded body peripherally disposed sleeve solved.

The housing has a plurality of openings and an axially movable in the cylindrical cavity of the housing control piston, wherein for controlling the hydraulic fluid flow between the inflow port, the working ports and the tank port, a control edge of the control piston is axially positionable to an opening of the housing, so as to the flow area for the Hydraulic fluid flow between the ports to change through the opening.

The control valve is preferably designed as a central valve and thus the housing as a central screw, whereby the camshaft adjuster is clamped against rotation with the camshaft.

By the invention is advantageously achieved that different threaded body can be combined with a sleeve or different sleeves with a threaded body. Another advantage is that the production and the heat treatment can be individually adapted to both components. In addition, different materials can be used for the threaded body and for the sleeve.

Different threaded bodies can vary in length, thread pitch and thread type and be adapted to an individually provided receptacle, for example the camshaft. The threaded body is preferably designed as a threaded rod and has a threaded portion, an expansion portion and a positive connection portion. The threaded portion is provided for anchoring, for example. With a camshaft. The expansion section is designed to provide the necessary for the screw connection elasticity. The positive connection section is designed for positive fastening with the sleeve. As an alternative to the form-fit section, it is also possible to provide a frictional connection section or a material connection section for frictional or cohesive and rotationally fixed attachment to the sleeve.

Different sleeves can vary in length, diameter and quality of manufacture and adapted to an individually provided for this purpose, for example. The hub of the camshaft adjuster.

The sleeve may have at one of its ends an attack body for an assembly tool, preferably for mounting the camshaft adjuster with the camshaft. The attack body is advantageously designed as a hexagon analogous to a hexagon screw. Alternative screw head shapes may be formed instead of the hex screw head.

In an advantageous embodiment of the invention, the threaded body on a positive locking element, which is received in a complementary receptacle of the sleeve, wherein by means of the positive connection, a connection between the sleeve and the threaded body is formed. The positive connection fixes the sleeve to the threaded body at least in the axial direction to each other. The complementary receptacle may preferably be arranged in the bottom of the sleeve or on an inner circumference or outer circumference of the sleeve.

Preferably, the positive-locking element additionally has surfaces on a peripheral surface, which mate with surfaces of the complementary receptacle of the sleeve such that a torque can be transmitted between the two components. For this purpose, as mentioned at the outset, an attack body for an assembly tool is formed by the sleeve.

Alternatively, the positive connection between the sleeve and the threaded body can not transmit sufficient torque for fastening the camshaft adjuster to the camshaft. For example, sleeve and threaded body are fixed axially and / or radially to each other, but leaves the positive connection a rotation between the sleeve and threaded body. In this case, the threaded body has an attack body for an assembly tool. The attack body is advantageously designed as a hexagon analogous to a hexagon screw. Alternative screw head shapes may be formed instead of the hex screw head. This rotation can be completely without resistance, so with game, be formed or at least up to a certain torque, which is not sufficient for attachment of the camshaft adjuster to the camshaft, be designed without play.

In a detailed embodiment of the invention, the complementary receptacle is disposed within the sleeve. Preferably, from an inner circumference or from the bottom at the surface facing the interior of the sleeve, the complementary receptacle can be arranged in the interior of the sleeve. Likewise, the sleeve may have a pin which has the complementary receptacle on its inner circumference.

In an alternative detailed embodiment of the invention, the complementary receptacle is located outside the sleeve. Preferably, from an outer periphery or from the bottom on the surface facing the outside of the sleeve, the complementary receptacle can be arranged in the interior of the sleeve. Likewise, the sleeve may have a pin which has on its outer circumference the complementary receptacle for the form-locking element of the threaded body.

In an advantageous embodiment of the invention, the sleeve has the cylindrical cavity with a guide surface, which axially movable leads the control piston, the guide surface may be formed by an inner peripheral surface of the sleeve itself or by an inner peripheral surface of an intermediate sleeve.

In a further embodiment of the invention, the sleeve is formed as a deep-drawn part or as a flow press. Advantageously, these manufacturing methods allow an improvement in economic production.

In a preferred embodiment of the invention, the threaded body is formed as a forming part. Advantageously, this manufacturing method allows an improvement in economic production.

In addition to forming, a machining process, preferably turning, may be used to form the final shape of the threaded body. Alternatively, the threaded body can be made exclusively by a machining process, preferably by turning. "

In a further embodiment, the threaded body has a central passage opening. Advantageously, this passage opening can be formed as an inlet connection, working connection or tank connection of the control valve.

In a very advantageous embodiment of the invention, the threaded body has an external thread which can be brought into engagement with an internal thread of a camshaft. Alternatively, the threaded body has an internal thread which can be brought into engagement with an external thread of a camshaft. Advantageously, so the thread, internal or external thread, the threaded body can be adapted to the thread of the camshaft or different threads of the threaded body can be adapted to different camshaft, without design or manufacturing engineering changes to the sleeve, preferably with the control piston arranged therein make to have to.

In a particularly preferred embodiment of the invention, the sleeve has a screw head on an end face of the sleeve, which is designed as a flange. Advantageously, both a stop for the camshaft adjuster and an attack body for an assembly tool are formed on the flange and thus arranged to save space. Alternatively, the screw head may be formed on an end face of the threaded body, wherein nevertheless the sleeve has a stop, preferably a flange, for the camshaft adjuster.

The inventive design of the control valve is on the one hand a more economical production of the control valve possible and on the other diverse configurations of different sleeves with different threaded bodies especially in the assembly developed which allow high flexibility in terms of a wide range of applications.

Brief description of the drawings

Embodiments of the invention are illustrated in the figures.

Show it:

1 a control valve designed as a central valve and

2 an inventive multi-part housing designed as a central valve control valve.

Detailed description of the drawings

1 shows a trained as a central valve control valve 1 ,

The control valve 1 has a multi-part housing 2 , a plastic sleeve 15 , a guide sleeve 3 , a control piston 4 , two compression springs 18 and 20 , a valve seat sheet 21 , a ball 19 , a control piston 4 , a spring support plate 33 and possibly a spacer 22 , All of the aforementioned components are coaxial with each other and to a common axis of rotation 34 arranged, which at the same time the axis of rotation 34 a camshaft adjuster or a camshaft.

The multi-part housing 2 , which is designed as a screw, is provided for the rotationally fixed attachment of the camshaft adjuster with the camshaft. The multi-part housing 2 consists of a sleeve 6 and a threaded body 5 , The plastic sleeve 15 is from an inner peripheral surface of the sleeve 6 added. The plastic sleeve 15 has channels and openings to supply hydraulic fluid from an inlet port P of the control valve 1 to the working connections A and B. The working ports A and B are at different, angularly offset positions as radial bores 24 and 25 the sleeve 6 arranged. The inlet port P is from a through hole 10 of the threaded body 5 educated. The passage opening 10 is as one to the axis of rotation 34 formed coaxial bore and passes completely through the threaded body 5 , The tank connection is located on the opposite side of the inlet port P. 13 of the control valve 1 ,

The control piston 4 is from the compression spring 18 subjected to force and against the circlip 17 pressed. The circlip 17 secures the axial position of the plastic sleeve 15 and the control piston 4 inside the sleeve 6 , The compression spring 18 supported on the one hand on the control piston 4 and on the other hand on the Federabstützblech 33 from. The spring support plate 33 is, as well as the guide sleeve 16 and the valve seat sheet 21 , with the plastic sleeve 15 firmly connected. The ball 19 is from the compression spring 20 against the valve seat sheet 21 pressed. These three components form a check valve, which the hydraulic fluid from the inlet port P in the interior of the control valve 1 allows, but prevents backflow.

The control piston 4 is about its outer periphery of a guide surface 9 the guide sleeve 16 guided. The housing 2 , or the sleeve 6 , has a hole 23 on which of the spacer 22 is closed. The spacer 22 positioned on the one hand, the plastic sleeve 15 so that the hydraulic fluid from the holes 24 and 25 to the control piston 4 can get. On the other hand, the spacer 22 in addition to its coaxial with the axis of rotation 34 arranged passage opening having a plurality of radial bores, which may include hydraulic fluid from the bore 23 to the control piston 4 can guide and thus the bore 23 as an additional inlet connection, working connection or tank connection can be available.

The control of the hydraulic fluid flow between ports P, T, A and B is known to those skilled in the art. The control of the hydraulic fluid to the working ports A and B, which lead to the working chambers of the camshaft adjuster are also known from the prior art and generate the relative displacement between the camshaft and crankshaft. The control piston 4 According to the prior art, it is displaced in its axial position by an actuating pin of an electromagnet, in particular a central magnet, so that the hydraulic medium can be distributed from the inlet port P to the working ports A and B.

The sleeve 6 has at the front 13 , on which the tank connection T is arranged, a flange 14 and at the front 13 opposite end face 30 a perforated bathing 35 , The inner peripheral surface 36 of the perforated floor 35 is circular and coaxial with the axis of rotation 24 arranged. This inner peripheral surface 36 is part of the complementary admission 8th for the positive-locking element 7 , wherein this inner peripheral surface 36 an outer peripheral surface 37 the positive connection section 27 of the threaded body 5 contacted and the threaded body 5 radial to the axis of rotation 34 fixed. Between the inner peripheral surface 36 and the outer peripheral surface 37 one or no radial play can be provided.

The inner peripheral surface 36 closes in the axial direction along the axis of rotation 34 and towards the front 13 an annular inner surface 40 on, acting as an axial stop for the threaded body 5 for axial positioning of the threaded body 5 to the sleeve 6 is trained. The circular inner surface 40 is part of the complementary admission 8th for the positive-locking element 7 and contacts an annular outer surface 41 the positive connection section 27 of the threaded body 5 ,

In addition, the complementary recording indicates 8th the sleeve 6 another inner peripheral surface 38 on, which has a larger diameter than the inner peripheral surface 36 Has. The inner peripheral surface 38 closes in the axial direction along the axis of rotation 34 and towards the front 13 to the annular inner surface 40 at. This inner peripheral surface 38 contacts an outer peripheral surface 39 the positive connection section 27 of the threaded body 5 and fixes the threaded body 5 in the radial direction to the axis of rotation 34 with the sleeve 6 , Between the inner peripheral surface 38 and the outer peripheral surface 39 one or no radial play can be provided.

At least either between the inner peripheral surface 38 and the outer peripheral surface 39 or between the inner peripheral surface 36 and the outer peripheral surface 37 the positive connection formed rotatably.

Alternatively, the inner peripheral surface 38 and the outer peripheral surface 39 and / or the inner peripheral surface 36 and the outer peripheral surface 37 each having a cylindrical shape and be provided with or without radial play. If no radial play is provided for at least one surface pairing, this frictional connection, preferably an interference fit, can form the rotationally fixed connection. If a radial play is provided for both surface pairings, then the rotationally fixed connection can be formed by shitting, gluing or soldering.

The threaded body 5 is in three sections, the form-fitting section 27 , the stretch section 26 and the threaded portion 31 , divided. The form-fitting section 27 has the cylindrical outer peripheral surface 37 , the circular outer surface 41 and the cylindrical outer peripheral surface 39 on. In the direction of the axis of rotation 34 closes to the cylindrical outer peripheral surface 39 the positive connection section 27 the stretch section 26 on, which has a smaller cross section, as a positive connection portion 27 or the threaded portion 31 , The stretch section 26 is formed in its length and in its cross section such that the desired biasing force can be realized. Continue in the axial direction along the axis of rotation 34 joins the stretch section 26 the threaded section 31 which has an external thread for engagement with an internal thread of a camshaft.

The threaded body 6 is formed as a formed part. The form-fitting section 27 with its surfaces for complementary recording 8th , the stretch section 26 and the threaded portion 31 are formed by material displacements. The external thread of the threaded section 31 is rolled. The passage opening 10 can either be drilled or formed by an extrusion process. Machining processes, for example, such as turning or grinding, can additionally find application for the formation of desired tolerance ranges.

The sleeve 6 points from that of the threaded body 5 interspersed soil 35 and then to the complementary recording 8th the cylindrical cavity 3 on, in which the aforementioned components are arranged. At the front 13 the sleeve 6 is a flange 14 formed, which is designed as a radially projecting collar. The flange 14 has an attack corpus 32 with a screw head 12 on and a stop surface 28 for contacting with a camshaft adjuster, the attack body 32 points on the outer circumference of the flange 14 several surfaces on which the screw head 12 form. The arrangement of the surfaces corresponds to an external hexagon. The stop surface 28 is designed as an annular surface and the other end face 30 oriented.

The sleeve 6 is formed as a forming part, preferably as a deep-drawn part or extruded part. The structure of the screw head 12 trained attack body 32 of the flange 14 as well as the cylindrical cavity 3 and the complementary recording 8th can be advantageously formed by this method. The hole in the ground 35 as well as the radial bores 23 . 24 . 25 can be formed by a stamping process. Machining processes, for example, such as turning or grinding, can additionally find application for the formation of desired tolerance ranges.

Due to the rotationally fixed connection between the positive connection section 27 of the threaded body 5 and the complementary recording 8th the sleeve 6 is a torque from a mounting tool, which on the screw head 12 trained attack body 32 acting on the threaded portion 31 of the threaded body 5 transfer. As a result, the control valve designed as a central valve 1 with its designed as a screw multi-part housing 2 be used for the rotationally fixed connection of a camshaft adjuster with a camshaft.

2 shows an inventive multi-part housing 2 a control valve designed as a central valve 1 , The structure is similar to the housing 2 from the 1 Therefore, only the differences will be discussed below.

The attack corpus 32 is from the positive connection section 27 of the threaded body 5 educated. The screw head 12 of the attacking body 32 is designed here as a hexagon socket. The flange 14 has a cylindrical outer surface and functionally has only the stop surface 28 which is provided for contacting with a camshaft adjuster. In addition, the flange 14 from the frontal area 13 spaced apart. The stretch section 26 and the threaded portion 31 have a largely uniform outer diameter. The arrangement and the design of the connections (inlet connection, working connection, tank connection) are neglected here in favor of clarification of the invention. The surface pairing of the inner peripheral surface 38 and the outer peripheral surface 39 may be formed as shown. The inner peripheral surface 38 is as hexagon socket and the outer peripheral surface 39 cylindrically shaped. Again, little or no play can be provided in this surface pairing.

The formed as a hexagon inner peripheral surface 38 Alternatively, a trained as an external hexagon outer peripheral surface 39 be paired, creating a rotationally fixed connection between the sleeve 6 and the threaded body 5 can be trained.

In contrast to the design of the control valve 1 to 1 according to the training 2 first the multi-part housing 2 mounted with a camshaft adjuster and a camshaft, which is followed by the assembly of the arranged in the cylindrical cavity member. The guide surface 9 of the cylindrical cavity 3 can directly from a control piston 4 be contacted.

LIST OF REFERENCE NUMBERS

1

control valve

2

casing

3

cylindrical cavity

4

spool

5

threaded body

6

shell

7

Form-fitting element

8th

Complementary recording

9

guide surface

10

Through opening

11

external thread

12

screw head

13

front

14

flange

15

Plastic sleeve

16

guide sleeve

17

circlip

18

compression spring

19

Bullet

20

compression spring

21

Valve seat plate

22

spacer

23

drilling

24

drilling

25

drilling

26

expansion portion

27

Form-fitting section

28

stop surface

29

Outer circumferential surface

30

front

31

threaded portion

32

attack body

33

Federabstützblech

34

axis of rotation

35

ground

36

Inner circumferential surface

37

Outer circumferential surface

38

Inner circumferential surface

39

Outer circumferential surface

40

palm

41

outer surface

A

working port

B

working port

P

inflow connection

T

tank connection

Claims (10)

Control valve ( 1 ) of a camshaft adjuster, - wherein the control valve ( 1 ) is flowed through to control the camshaft adjuster of hydraulic fluid and - the control valve ( 1 ) has an inflow port (P), a plurality of working ports (A, B) and a tank port (T), - wherein the control valve ( 1 ) a trained as a screw housing ( 2 ) with a cylindrical cavity ( 3 ), in which a control piston ( 4 ) is guided axially bewegbar, characterized in that the housing designed as a screw ( 2 ) is formed in several parts, which has a threaded body ( 5 ) and a sleeve ( 6 ), wherein the threaded body ( 5 ) with the threaded body ( 5 ) peripherally arranged sleeve ( 6 ) connected is. Control valve ( 1 ) according to claim 1, characterized in that the threaded body ( 5 ) a form-locking element ( 7 ), which in a complementary receptacle ( 8th ) of the sleeve ( 6 ), wherein by means of the positive connection, a connection between the sleeve ( 6 ) and the threaded body ( 5 ) is trained. Control valve ( 1 ) according to claim 2, characterized in that the complementary receptacle ( 8th ) within the sleeve ( 6 ) is arranged. Control valve ( 1 ) according to claim 2, characterized in that the complementary receptacle ( 8th ) outside the sleeve ( 6 ) is arranged. Control valve ( 1 ) according to claim 1, characterized in that the sleeve ( 6 ) the cylindrical cavity ( 3 ) with a guide surface ( 9 ), which the control piston ( 4 ) leads axially movable. Control valve ( 1 ) according to claim 1, characterized in that the sleeve ( 6 ) is designed as a deep-drawn part or extruded part. Control valve ( 1 ) according to claim 1, characterized in that the threaded body ( 5 ) is formed as a formed part. Control valve ( 1 ) according to claim 1, characterized in that the threaded body ( 5 ) a central passage opening ( 10 ) having. Control valve ( 1 ) according to one of claims 1 to 8, characterized in that the threaded body ( 5 ) an external thread ( 11 ), which is engageable with an internal thread of a camshaft. Control valve ( 1 ) according to one of claims 1 to 9, characterized in that the sleeve ( 6 ) a screw head ( 12 ) on a front side ( 13 ) of the sleeve ( 6 ), which as a flange ( 14 ) is trained.

Images