POSITION DETECTION DEVICE

• US 20140111228A1
• Filed: 07/09/2012
• Published: 04/24/2014
• Est. Priority Date: 07/14/2011
• Status: Active Grant

• Current Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Hartrampf, Ralf, Giefer, Andreas, Rake, Ludger
• Granted Patent: US 9,261,346 B2
• Time in Patent Office: Days
• US Class Current: 324/699
• CPC Class Codes: G01B 7/003 for measuring position, not involving coordinate determination coordinate measuring G01B7/004
• CPC Class Codes: G01D 5/24 by varying capacitance

Abstract

A position detection device having a first electrode pair, an electrically conductive body that forms an electrical resistor which is electrically connected to the electrodes of the first electrode pair and extends in a first direction (y), between them, and with a measurement electrode which is in electrically conductive contact with the surface of a measurement area of the body located between the electrodes of the first electrode pair and can move relative thereto. The body is electrically connected to the electrodes of a second electrode pair and extends between them in a second direction (x) such that the measurement area is located between the electrodes of the second electrode pair.

Claims

1-15. -15. (canceled)

16. A position detection device comprising:

first and second electrode pairs,

an electrically conductive body (10) that forms an electrical resistor which is electrically connected to electrodes (17, 18, 19, 20) of the first and the second electrode pairs and which extends in a first direction (y), between the electrodes (17, 18) of the first electrode pair, and in a second direction (x), between the electrodes (19, 20) of the second electrode pair, and

a measurement electrode (11) being in electrically conductive contact with a surface (12) of a measurement area (23) of the body (10) located between the electrodes (17, 18, 19, 20) of the first and the second electrode pairs and being movable in relation to the first and the second electrode pairs,

at least one voltmeter (24) being electrically connected to the measurement electrode (11), which voltmeter also being electrically connectable to at least one of a first electrode (18) of the first electrode pair and a first electrode (20) of the second electrode pair, for measuring an electric voltage between the first electrode (18;

20) concerned and the measurement electrode (11).

17. The position detection device according to claim 16, wherein the first and the second directions (x, y) are perpendicular to one another.

18. The position detection device according to claim 16, wherein the surface (12) of the measurement area (23) extends parallel to the first and the second directions (x, y).

19. The position detection device according to claim 16, wherein an operating voltage (UB) is applied by at least one operating voltage source (22) to the electrodes of at least one of the first electrode pair and the second electrode pair.

20. The position detection device according to claim 19, wherein a control unit (21) electrically connects, sequentially in time, the first and the second electrode pairs to the operating voltage source (22).

21. The position detection device according to claim 16, wherein an evaluation unit (25) either incorporates the voltmeter (24) or is coupled thereto, the position of the measurement electrode (11), on the surface (12) of the measurement area (23), is determined by the evaluation unit on a basis of the measured voltages.

22. The position detection device according to claim 16, wherein a first component is either connected to or comprises the body, and a second component is either connected to or comprises the measurement electrode which is mounted and movable on the first component.

23. The position detection device according to claim 21, wherein the position of the first and the second components, in relation to one another, can be determined by the evaluation unit (25).

24. The position detection device according to claim 23, wherein a shift lever device (1) for a vehicle, which comprises a support (2) forming one of the first and the second components and a shift lever (3) forming another of the first and the second components, which is movable relative to the support (2) to various shift lever positions (P, R, N, D) so that a currently engaged shift lever position is determinable by the evaluation unit (25).

25. The position detection device according to claim 24, wherein a vehicle transmission (5) is coupled to the evaluation unit (25), and the transmission is actuatable as a function of the currently engaged shift lever position.

26. The position detection device according to claim 16, wherein the position detection device is utilized for determining the position of the measurement electrode (11) on the surface (12) of the measurement area (23) such that, during a first step, an electric operating voltage (UB) is applied to the electrodes (17, 18) of the first electrode pair and a first electric voltage (Urn) is measured between the measurement electrode (11) and a first of the electrodes (18) of the first electrode pair,

during a second step, an electric operating voltage (UB) is applied to the electrodes (19, 20) of the second electrode pair and a second electric voltage (Um) is measured between the measurement electrode (11) and a first of the electrodes (20) of the second electrode pair, and

during a third step, the position (P1, P2, P3) of the measurement electrode (11) on the surface (12) of the measurement area (23) is calculated from the voltages measured.

27. The position detection device according to claim 26, wherein the second step is carried out later in time after the first step.

28. The position detection device according to claim 26, wherein the third step is either carried out at a same time as, or a later time than the second step.

29. The position detection device according to claim 26, wherein a currently engaged shift lever position (P, R, N, D) is determined by the evaluation unit (25).

30. A method of detecting a position with a position detection device having first and second electrode pairs, an electrically conductive body (10) that is electrically connected to electrodes (17, 18, 19, 20) of the first and the second electrode pairs and extends in a first direction (y), between the electrodes (17, 18) of the first electrode pair, and in a second direction (x), between the electrodes (19, 20) of the second electrode pair, a measurement electrode (11) which is in electrically conductive contact with a surface (12) of a measurement area (23) of the body (10) located between the electrodes (17, 18, 19, 20) of the first and the second electrode pairs and is movable in relation to the electrodes (17, 18, 19, 20) of the first and the second electrode pairs, at least one voltmeter (24) is electrically connected to the measurement electrode (11), the at least one voltmeter is electrically connectable to at least one of a first electrode (18) of the first electrode pair and a first electrode (20) of the second electrode pair so as to measure electric voltage between the measurement electrode (11) and the first electrode (18;

20) of either the first or the second electrode pair, the method comprising the steps of;

applying an electric operating voltage (UB) to the electrodes (17, 18) of the first electrode pair;

measuring a first electric voltage between the measurement electrode (11) and the first of the electrodes (18) of the first electrode pair;

applying an electric operating voltage (UB) to the electrodes (19, 20) of the second electrode pair;

measuring a second electric voltage between the measurement electrode (11) and a first of the electrodes (20) of the second electrode pair; and

calculating the position (P1, P2, P3) of the measurement electrode (11) on the surface (12) of the measurement area (23) from the measured first and the second voltages.