EP3257061A1

EP3257061A1 - Central actuator system for an oscillating motor adjuster of a camshaft

Info

Publication number: EP3257061A1
Application number: EP16703506.2A
Authority: EP
Inventors: Dietmar Schulze; Volker Stenger
Original assignee: Hilite Germany GmbH
Current assignee: Hilite Germany GmbH
Priority date: 2015-02-13
Filing date: 2016-02-03
Publication date: 2017-12-20
Anticipated expiration: 2036-02-03
Also published as: CN107004487A; US20170345538A1; US10340069B2; DE102015102066A1; CN107004487B; WO2016128279A1; EP3257061B1

Abstract

The invention relates to a central actuator (10, 10', 10"), in particular for a solenoid valve of an oscillating motor camshaft adjuster, comprising a housing (46), which surrounds the central actuator (10, 10', 10"), a pole tube (12) and a pole core (14), which are arranged inside at least one coil (52) generating a magnetic field, and an actuating plunger (20, 20', 20"), which is arranged on an armature (28, 28', 28") designed to be movable in the axial direction L in an armature space (60). According to the invention an end element (18) for closing the armature space (60) is provided, which comprises at least one pole core insert (22) having a central bore (24) and a bearing bushing (26) arranged in the central bore (24) of the pole core insert (22), wherein the actuating plunger (20, 20', 20") is axially movably mounted in the bearing bushing (26) and wherein the end element (18) also comprises an end cover (42) and is provided as a unit which can be pre-assembled.

Description

Central actuator for a Schwenkmotorversteller a camshaft

Technical area

The invention relates to a central actuator, in particular for a solenoid valve of a Schwenkmotornockenwellenverstellers an internal combustion engine of a motor vehicle.

State of the art

From DE 10 2005 049 663 A1 an electromagnet with a cylindrical hollow magnet body is known, which has a yoke, a pole core with a characteristic influencing armature counterpart and a housing, and a cylindrical coil and a cylindrical armature with guide rod and armature piston, which is displaceable to the pole is arranged.

In the electromagnet of the armature piston is mounted axially displaceably in a bearing tube or a bearing sleeve, wherein the bearing tube or the bearing sleeve ends at one end within the pole core or within the armature counterpart of the pole core and at another end to over the yoke, in particular up to the local Transverse wall of the housing extends, and at this end in the case of training as a bearing sleeve has the sleeve bottom. The pole core or its armature counterpart, which is penetrated by the guide rod, closes the housing.

DISCLOSURE OF THE INVENTION An object of the invention is to provide a cost-effective to manufacture and easy to mount central actuator, in particular for a solenoid valve of a Schwenkmotornockenwellenverstellers. The above object is achieved according to one aspect of the invention with the features of the independent claim. Favorable embodiments and advantages of the invention will become apparent from the other claims, the description and the drawings.

It is proposed a central actuator, in particular for a solenoid valve of a Schwenkmotornockenwellenverstellers comprising a housing which surrounds the central actuator. Furthermore, the central actuator comprises a pole tube and a pole core, which are arranged within at least one coil generating a magnetic field, and an actuating tappet, which is arranged on an armature, which is displaceable in an armature space in the axial direction. According to the invention a closing element is provided for closing the armature space, which comprises at least one Polkerneinsatz with a central bore and arranged in the central bore of Polkerneinsatzes bearing bush, wherein the actuating plunger is mounted axially displaceably in the bearing bush and wherein the closure element further comprises a cover and is intended as a preassembled unit.

The pre-assembled unit allows easy installation with a simultaneous axial fixation of the Polkerneinsatzes. The actuating plunger is also safely guided in the bearing bush, so that a guide of the armature, on which the actuating plunger is arranged, is ensured.

Preferably, the end cover has a central bore in which the bearing bush is arranged, whereby the unit is easily positioned.

Conveniently, the bearing bush with a plastic injection molding process made and the end cover and the Polkerneinsatz are provided as inserts, which are provided in the region of their central holes encapsulated by the material of the bearing bush. The plastic injection molding process represents a simple and very cost-effective manufacturing process, which makes it possible to produce the closure element simply and inexpensively.

According to an advantageous embodiment of the invention, the bearing bush in the axial direction arranged recesses for pressure equalization between the armature space and the outer space of the central actuator.

The pressure balance ensures a volume balance of the trapped hydraulic fluid or trapped air between the armature space and an outer space of the central actuator. Such pressure equalization is important both in dry operation, ie air-filled armature space, and thus also in operation with hydraulic fluid in the armature space. Even if hydraulic fluid has to be kept out of the area outside the pole tube, this hydraulic fluid within the pole tube is nevertheless of great advantage, since it can create a pressure equalization on both sides of the anchor. Likewise, the lubricating effect of the hydraulic fluid is advantageous, so that in this way a reduction of friction and wear is achieved.

For this purpose, in a particularly advantageous embodiment, recesses are provided in the bearing bush, which guide the hydraulic fluid from the hydraulic part of a solenoid valve to the electromagnetic part of the solenoid valve, that is to say the central actuator, in such a way that the end element is subjected to the same hydraulic pressure on both sides. It is also conceivable, however, to arrange the recesses in Polkerneinsatz and the end cap.

The bushing preferably has on its side facing the armature on a collar as a stop of the armature in its axial movement. Such a fixed stop holds the end face of the armature at a certain distance from the disc-shaped pole core insert and thus prevents sticking of the armature to the end face of the armature on the Polkerneinsatz. Gluing would change the movement behavior of the armature and necessitate the operation of the armature Significantly affect magnetic forces, thereby changing the overall dynamic behavior of the central actuator. Therefore, such a covenant as an anti-stick disc can positively influence the dynamic behavior as well as the energy consumption of a central actuator operated by magnetic forces.

Advantageously, the actuating tappet can be pressed into a central bore of the armature. Anchors and actuating tappets are usually made of different materials. The armature is preferably formed of soft iron, while the actuating plunger is made for example of non-ferrous metal, to also have the necessary material properties such as hardness for the operation of a solenoid valve. However, the armature must have substantially the correct magnetic properties to operate in the magnetic circuit of the coil. Therefore, for example, the armature can be provided with a bore into which the actuating tappet can be inserted, wherein it can preferably be pressed in, which produces a cost-effective and permanent connection between armature and actuating tappet.

According to an advantageous embodiment of the invention, the actuating plunger for pressure equalization between a front and a back of the armature between the armature and the bearing bush have one or more transverse bores, which open into a central, leading into the bore of the anchor longitudinal bore.

Another advantageous embodiment of the invention, on the other hand, provides for the actuating tappet to have flattenings which extend on both sides beyond an insertion region of the bore, and the bore is stepped and has an enlarged inner diameter beginning in the region of the flats. The flats and the enlarged inner diameter can be easily and inexpensively manufactured, so that the volume and pressure compensation can be ensured in a simple and cost-effective manner.

Alternatively, the actuating tappet and the armature can be provided in one piece, resulting in the elimination of the bore for receiving the plunger, a high Magnetic force results in a compact design. Furthermore, this can improve the coaxiality of the two components.

The anchor can be inexpensively manufactured from a free-cutting steel in this embodiment.

According to an advantageous embodiment of the invention, the armature can be designed to be displaceable in a non-magnetic sleeve in the axial direction pointing towards the pole core insert.

If this sleeve has an inner diameter extending over the entire working area passing over the armature, the armature can be guided over its entire length and it is ensured that the armature can not tilt, which would otherwise lead to high magnetic radial forces on the armature and thus would cause a high friction against the pole tube. If the pole tube and the pole core are made in one piece and the armature is designed to be displaceable therein in the axial direction pointing towards the pole core insert, according to an alternative embodiment, guidance of the armature can likewise be ensured. Preferably, the armature has at a end facing the end element as a guide surface on a diameter shoulder for guidance in the armature space. With the storage of the actuating plunger in the bearing bush as a second bearing this two-point bearing allows long bearing distance good guidance of the armature, since small Koaxialfehler can be compensated by an outer diameter of the Polkerneinsatzes to an inner diameter of the bearing bush and an outer armature diameter and a tappet outer diameter.

The guide surface of the armature may be formed polygonal according to an embodiment and circumferentially uniformly distributed flats for pressure equalization between a front and a back of the armature have.

A particularly inexpensive alternative embodiment provides that To provide guide surface of the armature as a cylindrical diameter paragraph with an enlarged outer diameter.

Advantageously, the housing can be produced by a plastic injection molding process. In this way, it is possible in a cost effective manner to manufacture the housing of the central actuator of injection-molded plastic, provided that the various components of the yoke are inserted in the injection molding process, which ensure the closed magnetic flux. The conclusion of the housing against an outer space of the Zentralaktuators forms the end cover, which is preferably secured by means of ultrasonic rivets to the housing.

Brief Description of the Drawings Further advantages will be apparent from the following description of the drawings. In the drawings, embodiments of the invention are shown. The drawings, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into meaningful further combinations.

They show by way of example:

1 shows a section through a central actuator after a first

Embodiment of the invention;

Fig. 2 section through the end element of the Zentralaktuators according to

3 shows a section through a central actuator after a second

Embodiment of the invention; 4 shows an armature of the second embodiment according to FIG. 3;

Fig. 5 is a section through a central actuator after a third

Embodiment of the invention and

Fig. 6 is an enlarged view of the armature with pressed-in

Actuating tappet of the third embodiment of FIG. 5.

Embodiments of the invention

In the figures, the same or similar components are numbered with the same reference numerals. The figures are merely examples and are not intended to be limiting.

Fig. 1 shows a section through a Zentralaktuator 10 according to a first embodiment of the invention. The central actuator 10, which is suitable in particular for a solenoid valve of a Schwenkmotornockenwellenverstellers, while comprising a pole tube 12 which is disposed within a cylindrically shaped, a magnetic field generating coil 52, and a housing 46 which surrounds the central actuator 10. The housing 46 is manufactured by a plastic injection molding process, so that it is possible in a cost-effective manner to manufacture the housing 46 and at the same time insert various components of a pole yoke 50 in the injection molding process, which ensure the closed magnetic flux.

Furthermore, the central actuator 10 comprises an enlarged in Fig. 2 illustrated end member 18, which closes the housing 46, wherein the end member 18 includes a Polkerneinsatz 22 with a central bore 24 and disposed in the central bore 24 of the Polkerneinsatzes 22 bushing 26. Furthermore, it includes a cover plate 42 and is provided as a preassembled unit. The end cover 42 is provided fastened to the housing 46, for example by means of ultrasonic rivets. For this, the housing 46 has an ultrasonic geometry in the form of a plurality of projections 62, which project through bores 64 of the end cover 42. The protrusions 62 are melt-deformed by the ultrasonic riveting so that the end cover 42 is securely fixed to the housing 46.

As can be seen in particular from FIG. 2, the end cover 42 also has a central bore 43, in which the bearing bush 26 is arranged.

Conveniently, while the bearing bush 26 is made with a plastic injection molding process and the end cover 42 and the Polkerneinsatz 22 are provided as inserts, which are inserted in the manufacture of the bearing bush 26 in the injection mold and encapsulated in the region of their central holes 24, 43 of the material of the bearing bush , As a result, a permanent sealing of the bearing bush 26 against the Polkerneinsatz 22 and the end cover 42 is given.

An actuating tappet 20 is arranged on an armature 28, which is designed to be displaceable within an armature space 60 in an axial direction L pointing to the pole core insert 22, and is mounted axially displaceably in the bearing bush 26, while the armature 28 is mounted in a non-magnetic sleeve 29 , This is stored in the pole tube 12 and a pole core 14. As can be seen, the sleeve 29 extends to a closed end of the cover 42 end of an armature space 60 and has a running over the entire armature 28 working area continuous inner diameter, so that it can be guided over its entire length. In addition, this ensures that the armature 28 can not be inclined, which would otherwise lead to high magnetic radial forces on the armature 28 and thus to a high friction against the pole tube 12. The sealing of the sleeve 29 takes place by means of an annular sealing element 56 which is arranged between a collar 58 of the sleeve 29 and the housing 46 and sealingly abuts against the end cover 42 and a part of the pole yoke 50. According to an embodiment, not shown, the pole tube 12 and the pole core 14 may be made in one piece. The sleeve 29 can be omitted in this case and the armature 28 is designed to be displaceable herein in the direction of the pole core insert facing axial direction. The bearing bush 26 has recesses 32 arranged in the axial direction for pressure equalization between the armature space 60 and the outer space 54 of the central actuator 10. The pressure balance ensures a volume balance of trapped hydraulic fluid or trapped air between the armature space 60 and an exterior space of the central actuator 10. Such a pressure equalization is important both in dry operation, ie air-filled armature space 60, ie also when operating with hydraulic fluid in the armature space 60.

The bushing 26 has on its armature 28 side facing a collar 40 as a stop of the armature 28 in its axial movement. Such a fixed stop holds the end face of the armature 28 at a certain distance from the disc-shaped pole core insert 22 and thus prevents sticking of the armature 28 with the end face of the armature 28 on the Polkerneinsatz 22. An adhesive would change the movement behavior of the armature 28 and the significantly affect the operation of the armature 28 necessary magnetic forces, so that the entire dynamic behavior of the central actuator 10 would be changed thereby. Therefore, such a collar 40 as an anti-glare disk can positively influence the dynamic behavior as well as the power consumption of a central actuator 10 which is operated with magnetic forces. The actuating plunger 20 can be pressed into a central bore 30 of the armature 28. If the actuating plunger 20 is made of a different material than the armature 28, this represents a favorable solution of the connection between the two components. The yoke 50, which may be formed of a plurality of plates and / or tubes, surrounds the coil 52 on its outer sides, whereby the coil 52 as completely surrounded by magnetic material, since inside the coil 52, the pole tube 12 is formed. As a result, the magnetic flux generated by the coil 52 is as low as possible concentrated on the volume range in which the armature 28 can move.

A pressure equalization between a front and a back of the armature 28 is made possible in that the actuating plunger 20 between the armature 28 and the bearing book 26 has one or more transverse bores 71 which in a central, leading into the bore 30 of the armature 28 longitudinal bore 72nd open, so that the armature 28 is acted upon on both sides with the same hydraulic pressure. The armature 28 can also be mounted by means of a two-point bearing, as described for a subsequent embodiment.

Fig. 3 shows a section through a central actuator 10 'according to a second embodiment of the invention. This differs from the first embodiment only in that the armature 28 'and the actuating plunger 20' are made in one piece. The two components shown in Fig. 4 are formed of the same material and the actuating plunger 20 'may be formed as well as the armature 28' of a soft magnetic material. This makes it possible to build the most compact central actuator 10 'possible.

A guide surface 66 at an end of the armature 28 'facing away from the end element 18 is polygonal as a diameter shoulder 75 and has circumferentially uniformly distributed flats 68, by means of which a pressure equalization between the front and the back of the armature 28' is made possible.

Serving as a guide surface 66 diameter paragraph 75 forms a first bearing point of the armature 28 '. As a second bearing point of the armature 28 'is the storage of the actuating pin 20' in a stepped recess 70 of the bearing bush 26, which in particular in Fig. 2 can be seen. This two-point bearing with a large bearing distance allows a good guidance of the armature 28 ', since small coaxial errors can be compensated by an outer diameter of the Polkerneinsatzes 22 to an inner diameter of the bearing bush 26 and a Ankeraußendurchmesser and a tappet outer diameter.

5 and 6, a further embodiment of the invention can be seen, which differs from the first embodiment, essentially by the design of the pressure equalization between the front and the back of the armature 28 ".

As also described for the first exemplary embodiment, the actuating tappet 20 "is pressed into a central bore 30" of the armature 28 ". In contrast to this, the essentially cylindrical actuating tappet 20" has flattenings 73 in the press-in region, which are designed, for example, milled or hammered to illustrate a volume or pressure equalization between the front and the rear side of the armature 28 ". The exemplary embodiment shown has, by way of example, three flattenings 73 distributed on the circumference.

As can be seen in particular from Fig. 6, which shows the armature 28 "with the pressed-in actuating plunger 20" in an enlarged view in section, the flats 73 extend on both sides beyond the press-in area of the bore 30 "beyond the actuating plunger 20" without a center The flats 73 do not extend as far as an end 74 of the actuating tappet 20 ", and the bore 30" is of stepped design and has an enlarged inner diameter beginning in the region of the flats 73 in order to compensate the volume over the Allow flattening 73 and the end 74. As a result, axial bores in the armature 28 "or longitudinal flat areas on the outside of the armature 28" can be dispensed with, which must be provided at the armature at high cost and, moreover, have a negative effect on the magnetic force. In order to provide the advantageous two-point bearing described above, the armature 28 "has in one end region a cylindrical diameter shoulder 75", which forms the guide surface 66 "with an enlarged outside diameter.

LIST OF REFERENCE NUMBERS

10, 10 ', 10 "central actuator

12 poles tube

14 pole core

18 end element

20, 20 ', 20 "actuating plunger

22 Polkernereinsatz

24 hole

26 bearing bush

28, 28 ', 28 "anchor

29 sleeve

30, 30 "bore

32 recess

40 fret

42 end cover

43 hole

46 housing

50 poljoch

52 coil

54 outdoor space

56 sealing element

58 fret

60 anchor space

62 advantage

64 hole

66, 60 "guide surface

68 flattenings

70 recess

71 cross bore

72 longitudinal bore

73 flattening 74 end

75, 75 "diameter paragraph L direction

Claims

claims

Central actuator (10, 10 ', 10 "), in particular for a solenoid valve of a swivel camshaft adjuster, comprising a housing (46) which encloses the central actuator (10, 10', 10"), a pole tube (12) and a pole core (14) which are arranged within at least one coil (52) generating a magnetic field, and an actuating tappet (20, 20 ', 20 ") which is arranged on an armature (28, 28', 28") which is located in an armature space (60 ) in the axial direction (L), characterized in that a closing element (18) for closing the armature space (60) is provided, which at least one Polkerneinsatz (22) with a central bore (24) and in the central bore ( 24) of the Polkerneinsatzes (22) arranged bearing bush (26), wherein the actuating plunger (20, 20 ', 20 ") in the bearing bush (26) is axially displaceably mounted and wherein the closing element (18) further comprises a cover (42) and as a preassemblable unit it is provided.

Central actuator (10, 10 ', 10 ") according to claim 1, characterized in that the end cover (42) has a central bore (43) in which the bearing bush (26) is arranged.

Central actuator (10, 10 ', 10 ") according to claim 2, characterized in that the bearing bush (26) is produced by a plastic injection molding process and the end cover (42) and the Polkerneinsatz (22) are provided as inserts, which in the region of its central Holes (24, 43) of the material of the bearing bush (26) are provided encapsulated.

Central actuator (10, 10 ', 10 ") according to one of the preceding claims, characterized in that the bearing bush (26) arranged in the axial direction (L) recesses (32) for pressure equalization between the armature chamber (60) and outer space (54) of the central actuator having.

Central actuator (10, 10 ', 10 ") according to one of the preceding claims, characterized in that the bearing bush (26) on its side facing the armature (28) a collar (40) as a stop of the armature (28, 28', 28 ") in its axial movement.

Central actuator (10, 10 ") according to any one of the preceding claims, characterized in that the actuating plunger (20, 20") in a central bore (30, 30 ") of the armature (28, 28") can be pressed.

Central actuator (10,

10 ") according to any one of the preceding claims, characterized in that the actuating plunger (20, 20") is formed of a soft magnetic material.

Central actuator (10) according to any one of the preceding claims, characterized in that the actuating plunger (20) for pressure equalization between a front and a back of the armature (28) between the armature (28) and the bearing bush (26) one or more transverse bores ( 71), which in a central, in the bore (30) of the armature (28) leading longitudinal bore (72) open.

Central actuator (10 ") according to one of the preceding claims 1 to 7, characterized in that the actuating plunger (20") has flats (73) which extend on both sides beyond an insertion region of the bore (30 "), and the bore (30 ") is stepped and has a beginning in the region of the flats (73), enlarged inner diameter.

Central actuator (10 ') according to one of the preceding claims 1 to 5, characterized in that the actuating plunger (20') and the armature (28 ') are integrally provided.

1 1. Central actuator (10, 10 ', 10 ") according to any one of the preceding claims, characterized in that armature (28, 28', 28") in a non-magnetic sleeve (29) in the direction of the pole core (22) axial direction (L ) executed displaceable.

12. Zentralaktuator (10, 10 ', 10 ") according to one of the preceding claims 1 to 10, characterized in that the pole tube (12) and the pole core (14) are made in one piece and the armature (28, 28', 28" ) is slidably configured therein in the axial direction (L) facing the pole core insert (22).

13. central actuator (10 ', 10' ') according to one of the preceding claims, characterized in that the armature (28', 28 ") at a the end element (18) facing end as a guide surface (66, 66") has a diameter shoulder (75 , 75 ") for guiding in the armature space (60).

14. Zentralaktuator (10 ') according to claim 13, characterized in that the

Guide surface (66) of the armature (28 ') is polygonal and circumferentially evenly distributed flats (68) for pressure equalization between a front and a back of the armature (28').

15. Zentralaktuator (10 ") according to claim 13, characterized in that the

Guide surface (66 ") of the anchor (28") is provided as a cylindrical diameter shoulder (75 ") with an enlarged outer diameter.

16. central actuator (10, 10 ', 10 ") according to any one of the preceding claims, characterized in that the housing (46) is made by a plastic injection molding process.

17. central actuator (10, 10 ', 10' ') according to claim 16, characterized in that the end cover (42) is secured by means of ultrasonic rivets to the housing (46).