Adjusting Device With Sealed Guide Cylinder

Abstract

An adjusting device having at least one tappet assembly. The at least one tappet assembly comprises a tappet, at least one guide cylinder, and a pole core. The tappet is arranged in the guide cylinder in a movable manner along a longitudinal axis, and a non-magnetic connection socket is arranged between the guide cylinder and the pole core. The guide cylinder and the pole core are arranged at a distance to each other in the longitudinal axis by means of the connection socket.

Claims

1. An adjusting device, comprising: a tappet assembly, wherein the tappet assembly comprises a tappet, a guide cylinder and a pole core, wherein the tappet is disposed such that the tappet is displaceable along a longitudinal axis in the guide cylinder, wherein between the guide cylinder and the pole core a non-magnetic connection bushing is disposed, and wherein that the guide cylinder and the pole core are disposed at a spacing in the longitudinal axis through the connection bushing.

2. The adjusting device of claim 1, wherein the connection bushing comprises a high-grade steel.

3. The adjusting device of claim 1, wherein the spacing between the guide cylinder and the pole core is up to 50% of a working stroke of the tappet.

4. The adjusting device of claim 1, wherein the connection bushing is connected pressure-tight with the pole core, the guide cylinder, or both the pole core and the guide cylinder, by a welded connection.

5. The adjusting device of claim 1, wherein the adjusting device comprises a first tappet assembly and a second tappet assembly, both of which are disposed in parallel and spaced apart on a connection plate, wherein the connection plate comprises a first cutout and a second cutout, wherein the first tappet assembly penetrates the cutout, wherein the second tappet assembly penetrates the second cutout, and wherein between at least one of the cutouts and one of the tappet assemblies a clearance is provided.

6. The adjusting device of claim 1, wherein the tappet assembly comprises an actuator that is in operational connection with a front end of the tappet.

7. The adjusting device of claim 6, wherein the actuator is magnetically controllable and encompassed by an actuator coil.

8. The adjusting device of claim 7, wherein in a nonactivated state of the tappet the connection bushing is disposed between the actuator coil and the actuator.

9. The adjusting device of claim 7, wherein between the guide cylinder and the pole core a magnetic flux flows through the connection bushing.

10. The adjusting device of claim 1, wherein the guide cylinder is formed of a first guide sleeve and a second guide sleeve which are connected pressure-tight with one another.

11. The adjusting device of claim 10, wherein the first guide sleeve is produced out of a non-magnetic material and supports the tappet in the longitudinal axis and the second guide sleeve is produced out of a soft magnetic material and supports the actuator in the longitudinal axis.

12. The adjusting device of claim 1, wherein a recuperating spring is provided which is stayed on the guide cylinder and is in operational contact with the tappet.

13. The adjusting device of claim 1, wherein the guide cylinder comprises a sealing on an outer surface.

14. The adjusting device of claim 5, wherein the guide cylinder comprises a contact face that is in contact on a connection side of the connection plate.

15. The adjusting device of claim 1, wherein a sliding bushing is provided by which a maximal working stroke of the tappet in the longitudinal axis is predetermined.

16. The adjusting device of claim 14, further comprising a housing opposite the connection side of the connection plate.

17. The adjusting device of claim 1, wherein the adjusting device is developed in a cartridge design.

18. A motor vehicle with an adjusting device of claim 1.

Description

[0026] In the following a preferred embodiment example of the invention will be described in detail with reference to the accompanying drawing. In the drawing depict:

[0027] FIG. 1 a perspective view of an adjusting device according to the invention with a tappet assembly with a guide cylinder closed as half-open cylinder by means of a lid-shaped pole core and a non-magnetic connection bushing, and

[0028] FIG. 2 a schematic and sectional view of the adjusting device according to FIG. 1.

[0029] In the following an adjusting device 1 according to a preferred embodiment example of the invention will be described in detail with reference to FIGS. 1 and 2.

[0030] FIG. 1 shows the adjusting device 1 with a first tappet assembly 3, a second tappet assembly 6 and a connection plate 10. The connection plate 10 is equipped to secure the adjusting device 1 on a not-shown cam shaft housing. The tappet assemblies 3, 6 are substantially of identical structure and parallel to one another and spaced apart and each comprises a tappet 31, 61 disposed such that it is longitudinally displaceable in a particular guide cylinder 34, 64 along a longitudinal axis 30, 60 by a working stroke 59, 89. The working stroke 59, 89 is depicted by means of double arrows in FIG. 2.

[0031] The particular tappet 31, 61 comprises a front end 32, 62 and a rear end 33, 63, wherein the front end 32, 62 projects through a guide cylinder opening 59 [sic: 49], 79, worked into the particular guide cylinder 34, 64, and at the rear end 33, 63 is disposed an actuator 35, 65.

[0032] For the purpose of connecting with the cam shaft housing, the adjusting device 1 or the connection plate 10 comprises several bolts 16. Furthermore, the first tappet assembly 3 and the second tappet assembly 6 are encompassed on the side, facing away from the connection side 15, of the connection plate 10 by a housing 8. The adjusting device 1 is consequently developed in a cartridge design that is distinguished thereby that the adjusting device 1 can be emplaced and secured on a cam shaft housing with low effort.

[0033] In FIG. 2 is evident that the connection plate 10 comprises a first cutout 11 and a second cutout 12, wherein the first cutout 11 is provided for the first tappet assembly 3 and the second cutout 12 for the second tappet assembly 6. The longitudinal axis 30 of the first tappet assembly 3 and the longitudinal axis 60 of the second tappet assembly 6 are oriented vertically with respect to the connection plate 10 and extend at a spacing from one another.

[0034] The particular tappet 31, 61 is guided through the cutout 11, 12 by means of the particular guide cylinder 34, 64, wherein the second tappet assembly 6 is held floatingly with a clearance 7 in the second cutout 12 so as to avoid a double fit with the cam shaft housing (not shown). The second tappet assembly 6 is correspondingly held movably, preferably by 0.5 mm, in the plane of the connection plate 10.

[0035] The clearance 7 can be realized either by a larger dimensioned cutout 11, 12 or through a smaller dimensioned outer circumference or diameter of the particular guide cylinder 34, 64. In the mounted state of the adjusting device 1 in the cutout 12, the clearance 7 is an annular gap between the connection plate 10 and the guide cylinder 34, 64. The clearance 7 or the floating bearing, moreover, during the mounting of the adjusting device 1 onto the cam shaft enables the self-centering of the guide cylinders 34, 64 by means of guide faces 55, 85 provided for this purpose. The guide faces 55, 85 are developed, for example, as bevels.

[0036] The particular guide cylinder 34, 64 is developed as two parts comprising a first guide sleeve 41, 71 and a second guide sleeve 42, 72 which are plugged pressure-tight together with a plug connection 51, 81. The first guide sleeve 41, 71 is produced of a non-magnetic material and comprises on an inner jacket surface 52, 82 an inner offset 50, 80. The second guide sleeve 42, 72 is set under form closure into the first guide sleeve 41, 71 up to the inner offset 50, 80. The second guide sleeve 42, 72 is produced of a soft magnetic material and is typically provided with a non-magnetic metal coating on the side facing the actuator 35, 65 or the tappet 31, 61, through which metal coating the friction during the axial movement of the tappet 31, 61 or of the actuator 35, 65 is stabilized. The metal coating is preferably a chromium-nickel alloy.

[0037] It is furthermore shown in FIG. 2 that the end of the particular guide cylinder 34, 64, associated with the rear end 33, 63, is closed by means of a lid-like pole core 44, 74 and a connection bushing 43, 73. The pole core 44, 74 is produced of a soft magnetic material. On the side, facing away from the guide cylinder 34, 64, of the pole core 44, 74 a permanent magnet 56, 86 is disposed.

[0038] Between the pole core 44, 74 and the guide cylinder 34, 64 or the second guide sleeve 42, 72 the connection bushing 43, 73 is disposed by which the particular guide cylinder 34, 64 is indirectly connected with the pole core 44, 74. The connection bushing 43, 73 is produced of a non-magnetic material, preferably a high-grade metal of an austenitic alloy, and welded to the guide cylinder 34, 64, or the particular second guide sleeve 41, 71 [sic: 42, 72], and the particular pole core 44, 74 to form a pressure-tight, gas-tight and fluid-tight connection. The guide cylinder 34, 64 is accordingly a half-open cylinder with a closed end and an open end that comprises the guide cylinder opening 49, 79.

[0039] The pole core 44, 74 and the guide cylinder 34, 64 are disposed such that they are spaced apart from one another through the connection bushing 43, 73, whereby through the connection bushing 43, 73 a magnetically permeable gap 45, 75 for a magnetic side flux is formed. The height of the particular gap 45, 75 in the longitudinal axis 30, 60 corresponds substantially to the maximal working stroke 59, 89 of the particular tappet 31, 61. However, discrepancies of 50% are feasible.

[0040] The second guide sleeve 42, 72 has an offset 38, 68, in contact on which a spring element 37, 67 rests. The spring element 37, 67 is, on the one hand, stayed on the offset 38, 68 and, on the other hand, is in operational connection with the tappet 31, 61 or with a spring plate 40, 70 of the tappet 31, 61. The first spring element 37 is a helical spring wound in the left-hand direction and the second spring element 67 is a helical spring wound in the right-hand direction, wherein the spring elements 37, 67 can be implemented as fiber glass-reinforced synthetic springs.

[0041] The spring plate 40, 70 in this embodiment example is developed as a flanged adapter disposed between an actuator 35, 65 and the particular tappet 31, 61. The actuator 35, 65 is in operational connection with the particular rear end 33, 63 of the tappet [31, 61]. About the actuator 35, 65 is disposed in each instance an electrically controllable actuator coil 36, 66 which can be activated for the advancing of the particular actuator 35, 65.

[0042] The permanent magnet 56, 86 exerts a force of attraction onto the actuator 35, 65 along the longitudinal axis 30, 60 such that the actuator 35, 65 is pulled into a retracted position or is pulled by the permanent magnet 56, 86 and consequently is in contact on the pole core 44, 74. This state corresponds to the nonactivated state. The spring element 37, 67 is hereby compressed, whereby a prestress force is provided that is lower than the force of attraction of the particular permanent magnet 56, 86. The actuator 35, 65 and the tappet 31, 61 assume the retracted position or the nonactivated state.

[0043] To advance the particular actuator 35, 65, the actuator coil 36, 66 is energized and a magnetic field is build up which induces a magnetic force onto the actuator 35, 65. The magnetic force acts in the same direction as the prestress force provided by the spring element 37, 67, which prestress force acts against the force of attraction of the permanent magnet 56, 86. The sum of the magnetic force and the prestress force is greater than the force of attraction exerted by the permanent magnet 56, 86. The particular actuator 35, 65 and the particular tappet 31, 61 are consequently advanced under guidance in the corresponding guide cylinder 34, 64 axially along the longitudinal axis 30, 60 until the front end 32, 62 of the particular tappet 31, 61 engages into a groove of a cam shaft (not shown). The cam shaft (not shown) herein rotates about an axis extending perpendicularly to the particular longitudinal axis 30, 60 of the tappets 31, 61. The tappet 31, 61 is in the activated state.

[0044] The maximal working stroke 59, 89 of the particular tappet 31, 61 is set by means of a sliding bushing 39, 69, which is disposed within the particular guide cylinder 34, 64 and is stayed on an inner offset 50, 80 in the longitudinal axis 30, 60 and is set up so as to establish at the maximal working stroke 59, 89 an operational connection with the spring plate 40, 70.

[0045] For resetting the particular tappet 31, 61 the current of the particular actuator coil 36, 66 is turned off and the permanent magnet [56, 86] pulls the actuator 35, 65 together with the tappet 31, 61 back into the guide cylinder 34, 64 until the actuator 35, 65 is in contact on the pole core 44, 74. The spring element 37, 67 is consequently again compressed and the prestress force is provided. In this nonactivated state the gap 45, 75 for the magnetic side flux is disposed in a plane between the actuator coil 36, 66 and the actuator 35, 65.

[0046] The first guide sleeve 41, 71 and the second guide sleeve 42, 72 herein regionally encompass the particular tappet 31, 61, wherein the second guide sleeve 42, 67 [sic: 72] is disposed in the region of the rear end 33, 63 and regionally supports the particular actuator 35, 65 along the longitudinal axis 30, 60. For this purpose, the actuator 35, 65 is developed in the form of a cylinder and emplaced on the particular rear end 33, 63 of the particular tappet 31, 61. The connection between the particular actuator 35, 65 and the particular tappet 31, 61 can be one of form closure, force closure, adhesion connection or the like.

[0047] An especially simple mounting of the adjusting device 1 results from the shaping of the guide cylinders 34, 64 of the first tappet assembly 3 and the second tappet assembly 6. The particular first guide sleeve 41, 71 is introduced from the connection side 15 into the first cutout 11 or the second cutout 12 and is in each instance in contact, by means of a contact face 46, 76, on the connection side 15 of the connection plate 10. The contact face 46, 76 is worked or molded in the manner of a projecting flange onto the particular first guide sleeve 41, 71. On one of the outer surfaces 47, 77 of the particular first guide sleeve 41, 71 a sealing 48, 78 is disposed through which the particular outer surface 47, 77 of the particular tappet assembly 3, 6 cooperates with a cam shaft housing. Consequently, a connection is established that is liquid-, gas- and pressure-tight with respect to the outer surface 47, 77 between the particular tappet assembly 3, 6 and the cam shaft housing. According to definition, the outer surface 47, 77 is, on the one side, the outer jacket surface and the surface of the front side between the contact face 46, 76 and the guide cylinder opening 49, 79.

[0048] In particular, from the cooperation of the tappet assemblies 3, 6 that are closed pressure-tight at the rear end and the sealings 48, 78 there results the advantage that the adjusting device 1 can be placed pressure-tight onto a cam shaft housing even in the presence of generous fabrication tolerances. The clearance 7 between at least one of the cutouts 11, 12 and at least one of the tappet assemblies 3, 6 compensates generous tolerances without a liquid leakage developing between the adjusting device 1 and the cam shaft housing.

[0049] According to the invention, an adjusting device 1 can consequently be provided that enables generous tolerances in the fabrication of the adjusting device 1 as well as of the cam shaft housing and thus is cost-effective of production and mounting and simultaneously realizes a reliable sealing. Simple compensation of fabrication tolerances is enabled through the clearance 7 between the at least one tappet assembly 3, 6, whereby through the cooperation of the tappet assembly 3, 6, sealed by means of the connection bushing 43, 73, and the sealings 48, 78 a reliable sealing effect is accomplished which can be realized in an especially simple manner.

LIST OF REFERENCE NUMBERS

[0050] 1 Adjusting device

[0051] 3 First tappet assembly

[0052] 6 Second tappet assembly

[0053] 7 Clearance

[0054] 8 Housing

[0055] 10 Connection plate

[0056] 11 First cutout

[0057] 12 Second cutout

[0058] 15 Connection side

[0059] 16 Bolts

[0060] 30 Longitudinal axis

[0061] 31 Tappet

[0062] 32 Front end

[0063] 33 Rear end

[0064] 34 Guide cylinder

[0065] 35 Actuator

[0066] 36 Coil

[0067] 37 Spring element

[0068] 38 Offset

[0069] 39 Sliding bushing

[0070] 40 Spring plate

[0071] 41 First guide sleeve

[0072] 42 Second guide sleeve

[0073] 43 Connection bushing

[0074] 44 Pole core

[0075] 45 Gap

[0076] 46 Contact face

[0077] 47 Outer surface

[0078] 48 Sealing

[0079] 49 Guide cylinder opening

[0080] 50 Inner offset in 41

[0081] 51 Plug connection

[0082] 52 Inner jacket surface

[0083] 55 Guide face

[0084] 56 Permanent magnet

[0085] 59 Working stroke

[0086] 60 Longitudinal axis

[0087] 61 Tappet

[0088] 62 Front end

[0089] 63 Rear end

[0090] 64 Guide cylinder

[0091] 65 Actuator

[0092] 66 Coil

[0093] 67 Spring element

[0094] 68 Offset

[0095] 69 Sliding bushing

[0096] 70 Spring plate

[0097] 71 First guide sleeve

[0098] 72 Second guide sleeve

[0099] 73 Connection bushing

[0100] 74 Pole core

[0101] 75 Gap

[0102] 76 Contact face

[0103] 77 Outer surface

[0104] 78 Sealing

[0105] 79 Guide cylinder opening

[0106] 80 Inner offset in 71

[0107] 81 Plug connection

[0108] 82 Inner jacket surface

[0109] 85 Guide face

[0110] 86 Permanent magnet

[0111] 89 Working stroke