EP0554900B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electric motor with inductive position detector
Assignee: L3 Magnet Motor GmbH
•
Filing: 1993-02-05
•
Granted: 1998-08-05
•
Expires: 2013-02-05
Abstract
Abstract A position detector determining the relative position of the rotor of an electric motor with respect to its stator has a power transmission device in the form of a coil (S1) at the stator end. The power is received in a coil arrangement (R1) revolving with the rotor. The current flows through another coil arrangement (R2) which has rectangular or sinusoidal sections distributed over the circumference. At the stator end, two coils with sinusoidal variation are arranged over the circumference of a circular track. In these coils (S2,S3), two signals with sinusoidal variation dependent on the rotor position are generated which are phase-shifted with respect to one another. These phase-shifted signals are processed in evaluating electronics (16) to form position signals. <IMAGE>
Inventors
- 👤 Peter Dr. Ehrhart
- 👤 Werner Dr. Weck
- 👤 Andreas Dr. Gründl
- 👤 Bernhard Hoffmann
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 13:10
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/20; G01D5/204; G01D5/2073
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
239 words
An electric motor comprising an inductively
operating position detector for detecting the relative
position of the rotor (10) of the electric
motor (2) with respect to the stator (6), comprising
the following features: the stator (6) has an energy transmission means
(S1) attached thereto; attached to the rotor (10) are an energy receiving
means (R1) and an energy transmitting
means (R2) which delivers position-dependent
signals, the stator (6) has a signal receiving means (S2,
S3) attached thereto, with the transmitting
means on the rotor side and the signal receiving
means (R2; S2, S3) on the stator side, for generating
position-dependent signals, consisting
of coil windings extending in planes perpendicular
to the axis of rotation of the rotor (10),
and an evaluation unit (16) connected to the signal
receiving means (S2, S3), characterized in that the evaluation unit (16) is designed to evaluate
the mutually phase-shifted signals that are
delivered from the signal receiving means (S2, S3)
of the stator (6), and that the number of the wavelengths of the transmitting
coil windings (R2) on the rotor side, having
a sinusoidal or a rectangular pattern, and of the
receiving coil windings (S2, S3) on the stator side,
having a sinusoidal pattern, at the circumference
each is either equal to the pole pair number of the
excitation means of the rotor (10) or corresponds to
an integral fraction of the pole pair number of the
excitation means of the rotor (10).
Claim 2
Dependent Claim
44 words
The electric motor of claim 1, characterized in that the transmitting coil windings
(R2) on the rotor side have an approximately rectangular
pattern in circumferential direction and the
receiving coil windings (S2, S3) on the stator side
have a sinusoidal pattern in circumferential direction.
Claim 3
Dependent Claim
37 words
The electric motor of claim 1 or 2, characterized in that all transmitting and receiving
means on the stator side and all transmitting and
receiving means on the rotor side are accommodated
on one common disc each.
Claim 4
Dependent Claim
31 words
The electric motor of claim 3, characterized in that the transmitting and receiving
means are realized in the form of conductive tracks
on the discs designed as circuit boards (12, 14).
Claim 5
Dependent Claim
43 words
The electric motor of claim 4, characterized in that the two phase-shifted signals
of the receiving means (S2, S3) on the stator side
are generated by two mutually phase-shifted coil
conductive tracks on the front and rear sides of the
circuit board (12).
Claim 6
Dependent Claim
69 words
The electric motor of claim 4, characterized in that the two phase-shifted signals
of the signal receiving means (S2, S3) on the stator
side are generated by two mutually phase-shifted
coil conductive tracks, the respective first wavelength
halves thereof being located on the front and
rear sides, respectively, and the respective second
wavelength halves thereof being located on the rear
and front sides, respectively, of the circuit board
(12).
Claim 7
Dependent Claim
47 words
The electric motor of any of claims 1 to 6, characterized in that the transmitting and receiving
means on the stator side and on the rotor side are
spaced in the direction of the relative axis of rotation
by a distance of 30 mm at the most.
Claim 8
Dependent Claim
23 words
The electric motor of any of claims 1 to 7, characterized in that it is formed with a rotor excited
by permanent magnets.
Claim 9
Dependent Claim
44 words
The electric motor of any of claims 1 to 9, characterized in that the receiving means (S2 to S4)
on the stator side comprises receiving coil windings
(S4) for position-independent determination of a
reference quantity derived from the frequency of the
energy transmission signal.
Claim 10
Independent Claim
42 words
A method of positioning the rotor position and/or
for evaluating the speed of an electric motor
according to any one of claims 1 to 9, characterized in that the output signal of the
evaluation unit is processed for positioning and
evaluating, respectively.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.