Electromagnetic positioning system and operating method

Patent metadata

Field	Value
Publication number	US-10910137-B2
Application number	US-201716337024-A
Country	US
Kind code	B2
Filing date	Sep 6, 2017
Priority date	Sep 27, 2016
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

An electromagnetic positioning system (1), including a valve train adjustment system for combustion engines, including a bistable electromagnetic positioning device (2) having a positioning element (3) for interacting with a positioning partner, the positioning element being adjustable between a retracted position (E) and an extended position (A) along an axis of adjustment (A) and having permanent magnet means (5) at least in sections.

First claim

The invention claimed is:

1. An electromagnetic positioning system ( 1 ), in particular a valve train adjustment system for combustion engines, comprising a bistable electromagnetic positioning device ( 2 ) having a positioning element ( 3 ) for interacting with a positioning partner, said positioning element ( 3 ) being adjustable between a retracted position (E) and an extended position (A) along an axis of adjustment (V) and having permanent magnet means ( 5 ) at least in sections, the permanent magnet means ( 5 ) being adjustable between axially spaced first and second core parts ( 8 , 9 ) by adjustment of the positioning element ( 3 ) along the axis of adjustment (V) and adhering to the first core part ( 8 ) with a permanent-magnetic holding force when the positioning element ( 3 ) is in the retracted position (E) and adhering to the second core part ( 9 ) with a permanent-magnetic holding force when the positioning element ( 3 ) is in the extended position (A), and the positioning device ( 2 ) having first and second coils which can be controlled via control means, and the control means being configured to control the first and second coil means ( 10 , 11 ) in such a manner that, in a first operating mode for adjusting the positioning element ( 3 ) from the retracted position (E) into the extended position (A), the first coil ( 10 ) responds to an electrical control signal of the control means by generating a counterforce which counteracts the holding force of the permanent magnet means ( 5 ), repels the permanent magnet means ( 5 ) and detaches them from the first core part ( 8 ), and in a second operating mode for adjusting the positioning element ( 3 ) from the extended position (A) into the retracted position (E), the second coil ( 11 ) responds to an electrical control signal of the control means by generating a counterforce which counteracts the holding force of the permanent magnet means ( 5 ), repels the permanent magnet means ( 5 ) and detaches them from the second core part ( 9 ), wherein
evaluating means ( 13 ) for detecting an induction signal which can be generated by adjustment of the positioning element ( 3 ) from the retracted position (E) into the extended position (A) along the axis of adjustment (V) are assigned to the second coil ( 11 ), and the control means are configured in such a manner that they de-energize the second coil ( 11 ) in the first operating mode at least during a detection phase for detecting the induction signal,
and/or
that evaluating means ( 13 ) for detecting an induction signal which can be generated by adjustment of the positioning element ( 3 ) from the extended position (A) into the retracted position (E) along the axis of adjustment (V) are assigned to the first coil ( 10 ), and the control means are configured in such a manner that they de-energize the first coil ( 10 ) in the second operating mode at least during a detection phase for detecting the induction signal.

2. The electromagnetic positioning system according to claim 1 , wherein the evaluating means ( 13 ) are configured to respond to the absence of an induction signal and/or to a delayed induction signal by outputting an error signal and/or by storing error information and/or wherein the evaluating means are configured to respond to an induction signal by outputting an acknowledgement signal and/or by storing acknowledgement information.

3. The electromagnetic positioning system according to claim 1 , wherein the control means ( 12 ) are configured to respond to the absence of an induction signal by outputting a new control signal to the first or second coil ( 10 , 11 ).

4. The electromagnetic positioning system according to claim 1 , wherein the positioning element ( 3 ) is disposed so as to have a tappet portion ( 4 ) axially passing through the second core part ( 9 ).

5. The electromagnetic positioning system according to claim 1 , wherein the positioning element ( 3 ) is disposed so as to interact with a positioning partner which is configured and disposed so as to not exert any mechanical restoring force for adjusting the positioning element ( 3 ) from the extended position (A) into the retracted position (E).

6. The electromagnetic positioning system according to claim 1 , wherein the first coil ( 10 ) is configured to generate a stronger magnetic field than the second coil ( 11 ) when both coils are energized to the same degree.

7. The electromagnetic positioning system according to claim 1 , wherein the permanent magnet means ( 5 ) are at least partially disposed axially between the axially spaced coils ( 10 , 11 ).

8. The electromagnetic positioning system according to claim 1 , wherein the evaluating means ( 13 ) and the control means are formed by shared logic means.

9. A method for operating an electromagnetic positioning system ( 1 ) according to claim 1 , wherein in the first operating mode, the control means supply a control signal to the first coil ( 10 ), which causes the positioning element ( 3 ) to be adjusted from the retracted position (E) into the extended position (A), and during said adjustment movement an induction signal generated in the second coil ( 11 ) by the adjustment of the positioning element ( 3 ) is detected by the evaluating means ( 13 ) assigned to the second coil ( 11 ), and that the control means de-energize the second coil ( 11 ) in the first operating mode at least during a detection phase for detecting the induction signal, and/or in the second operating mode, the control means supply a control signal to the second coil ( 11 ), which causes the positioning element ( 3 ) to be adjusted from the extended position (A) into the retracted position (E), and that during said adjustment movement an induction signal generated in the first coil ( 10 ) by the adjustment of the positioning element ( 3 ) is detected by the evaluating means ( 13 ) assigned to the first coil ( 10 ), and the control means de-energize the second coil ( 10 ) in the second operating mode at least during a detection phase for detecting the induction signal.

10. A use of an electromagnetic positioning system ( 1 ) according to claim 1 for adjusting a cam follower of a valve train of a combustion engine, in a motor vehicle.

11. The electromagnetic positioning system according to claim 1 , wherein the evaluating means ( 13 ) are assigned to the second coil ( 11 ) and are configured in such a manner that they de-energize the second coil ( 11 ) during the entire first operating mode.

12. The electromagnetic positioning system according to claim 1 , wherein the evaluating means ( 13 ) are assigned to the first coil ( 10 ) and are configured in such a manner that they de-energize the first coil ( 10 ) during the entire second operating mode.

13. The electromagnetic positioning system according to claim 2 , wherein the evaluating means are configured to respond to a timely induction signal.

14. The electromagnetic positioning system according to claim 4 , wherein the tappet portion ( 4 ) axially passes through only the second core part.

15. The electromagnetic positioning system according to claim 5 , wherein the positioning partner is a cam follower.

16. The electromagnetic positioning system according to claim 7 , wherein the permanent magnet means ( 5 ) are entirely disposed axially between, at an axial distance from, the axially spaced coils ( 10 , 11 ).

17. The electromagnetic positioning system according to claim 8 , wherein the shared logic means is an engine control unit.

18. The method according to claim 9 , wherein the control means de-energize the se

Assignees

• Eto Magnetic Gmbh

Inventors

• Bürssner Jörg
• Vincon Peter

Classifications

• H01F2007/1692

  Electromagnets or actuators with two coils · CPC title

• H01F7/1646 Primary

  Armatures or stationary parts of magnetic circuit having permanent magnet · CPC title

• H01F2007/1669

  Armatures actuated by current pulse, e.g. bistable actuators · CPC title

• H01F7/1872

  Bistable or bidirectional current devices (relays H01H47/226) · CPC title

• H01F7/064 Primary

  Circuit arrangements for actuating electromagnets (circuit arrangements for obtaining special operating characteristics H01F7/18; driving circuits for electromagnets making use of a switching regulator H01H47/325) · CPC title