Patents by Inventor Christoph Loef

Christoph Loef has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20110075797
    Abstract: The invention provides a device for a computer tomography gantry (91) for transferring contactlessly electrical energy from a stationary part of the gantry (92) to a rotary part of the gantry (93), wherein the device comprises a first power transformer, a second power transformer, wherein the first and the second power transformers are adapted for transferring the electrical energy, wherein the first power transformer comprises a first winding (506, 507, 542, 602, 601, 1202, 1301, 1401) out of the group consisting of a first set of primary windings and a first set of secondary windings of the first power transformer, wherein the second power transformer comprises a second winding (508, 509, 543, 603, 604, 1204, 1302, 1402) out of the group consisting of a second set of primary windings and a second set of secondary windings of the second power transformer, wherein the first set of primary windings and the second set of primary windings being adapted to be mounted on the stationary part of the gantry, wherein
    Type: Application
    Filed: May 26, 2009
    Publication date: March 31, 2011
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Christoph Loef, Peter Luerkens, Bernd Ackermann
  • Publication number: 20110074534
    Abstract: The invention provides a transformer for a computer tomography gantry (91) for transfering contactlessly electrical energy from a stationary part of the gantry (92) to a rotary part of the gantry (93), wherein the transformer comprises a set of primary windings (103, 105, 203, 204), a set of secondary windings (103, 105, 203, 204), a set of first cores (101, 202, 301), a set of second cores (101, 202, 301), wherein the set of primary windings (103, 105, 203, 204) being arranged at the set of first cores (101, 202, 301) on the stationary part of the gantry (92), such that a winding of the set of primary windings (103, 105, 203, 204) is adapted to induce a magnetic flux into a core of the set of first cores (101, 202, 301), wherein the set of secondary windings (103, 105, 203, 204) being arranged at the set of second cores (101, 202, 301) on the rotary part of the gantry (93), such that a winding of the set of secondary windings (103, 105, 203, 204) is adapted to induce a magnetic flux into a core of the set of
    Type: Application
    Filed: May 27, 2009
    Publication date: March 31, 2011
    Applicant: Koninklijke Philips Electronics N.V.
    Inventors: Christoph Loef, Johannes Bathasar Maria Soetens
  • Publication number: 20110075796
    Abstract: The present invention refers to a high-voltage power supply circuit for inductively transmitting electrical energy from a stationary part to a load on a rotary part which requires a non-symmetrical voltage transfer, for example, an X-ray tube of an X-ray computed tomography device. The circuit may be realized as a resonant-type power converter circuit with a single rotary power transformer (500) or more than one such power transformer, where at least two separate DC/AC power inverter stages provide two individually controllable AC input voltages (U1, U2) to different windings (511, 512) of a multi-primary coil belonging to the rotary power transformer. Two output voltages supplied by the multi-secondary coil (521, 522, 523, 524) of said transformer which are derived from the two individually controllable AC input voltages are fed to the tube electrodes for powering the X-ray tube.
    Type: Application
    Filed: May 27, 2009
    Publication date: March 31, 2011
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Christoph Loef, Peter Luerkens
  • Patent number: 7852986
    Abstract: A power supply for generating a high output voltage for supplying an X-ray generator system with at least one X-ray source (17), especially for computer tomography (CT) applications is disclosed, wherein the high output voltage comprises at least two different high output voltage levels (U1; U1±U2) which are fast switchable so that spectral CT measurements can be conducted with one conventional X-ray tube (17). Furthermore, an X-ray tube generator system comprising such a power supply and at least one X-ray tube (17), as well as a computer tomography (CT) apparatus comprising such a power supply is disclosed.
    Type: Grant
    Filed: August 21, 2007
    Date of Patent: December 14, 2010
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Christoph Loef, Gereon Vogtmeier, Günter Zeitler
  • Patent number: 7830685
    Abstract: A power supply power supply (30) comprising a DC voltage supply, a control unit and a plurality of high voltage channels (33a-33d) is suggested. Each high voltage channel (33) includes an inverter (IKTV), a resonance circuit, a transformer (TR), and a rectifier (RECT). The resonance circuit cooperates with the inverter (INV). The inverter (INV) is formed by a first switching unit and a second switching unit whereby a voltage of a first polarity can be applied to the resonance circuit in a first switching state, whereas a voltage of a second polarity can be applied to the resonance circuit in a second switching state. The switching states can be switched by the control unit in such a manner that in a first mode of an operation for high output power, the output power can be adjusted by changing the switching frequency in the range of the resonance frequency.
    Type: Grant
    Filed: January 26, 2006
    Date of Patent: November 9, 2010
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Bernhard Wagner, Bernd Freiheit-Jensen, Christian Vollertsen, Christoph Loef, Cornelius Paul, Frank Mueller, Klaus Hoffmann, Marc Klingelhoeller, Wolfgang Rexhausen
  • Publication number: 20100277095
    Abstract: The present invention relates to a power supply device for supplying power to a load, preferably a LED, comprising a first circuitry (12) with an inverter unit (24) adapted to provide an AC voltage, preferably a rectangular voltage, and a resonant circuit (30) with a capacitance (32) and an inductance (34), a second circuitry (14) with a rectifier unit (42), a switch (64) and said load (60), said switch being adapted to switch said load on and off, a controller unit (16) adapted to control said switch (64) as to adjust the power provided to said load (60) without any measurement signal from said primary circuitry (12), and a transformer (18) with a primary side (20) and a secondary side (22), said primary side being connected to said first circuitry (12) and said secondary side (22) being connected to said second circuitry (14), preferably said rectifier, so that said first and second circuitries are galvanically isolated.
    Type: Application
    Filed: August 29, 2007
    Publication date: November 4, 2010
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N V
    Inventors: Christoph Loef, Matthias Wendt
  • Patent number: 7782999
    Abstract: Systems and methods for data acquisition in computed tomography (CT) applications are provided. The systems and methods are particularly adapted for scanning and acquiring/processing data in connection with high-power cone-beam CT applications. The electron beam is moved/scanned along the anode surface to multiple focal positions. Data acquisition for a full projection at one focus position and one view angle is achieved by activating each focus position multiple times during the data acquisition for one angle of the gantry. The detector array and associated data processing system are adapted to rapidly switch between the different focus positions during the acquisitions for one view angle and to collect all data belonging to the same projection into the same data set. Adaptive electron optics are utilized to move/scan the electron beam along the anode surface to the various focus positions.
    Type: Grant
    Filed: September 16, 2006
    Date of Patent: August 24, 2010
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Astrid Lewalter, Rainer Pietig, Guenter Zeitler, Kai Eck, Christoph Herrmann, Rainer Kiewitt, Christoph Loef, Oliver Muelhens, Carolina Ribbing, Georg Rose, Matthias Simon, Olaf Wischhusen
  • Patent number: 7746208
    Abstract: The present invention describes a winding for a transformer comprising first (60) and second (70) planar sections which are arranged parallel to each other. First (1, e.g., from 602 to 603)) and second (2, e.g., from 703 to 704)) current paths are arranged on the first and second planar sections. The first and second current paths are connected to each other by means of an interconnection (603/703). The first and second current (603/703) paths are respectively angled with respect to a direction along which the first and second planar sections are extending.
    Type: Grant
    Filed: December 8, 2006
    Date of Patent: June 29, 2010
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Christoph Loef, Bernd Ackermann
  • Publication number: 20100027306
    Abstract: A primary circuit (1) for feeding a secondary circuit (2) comprises a switch circuit (10) with switches (11-14) controlled by a control circuit (40) for bringing the primary circuit (1) into first or second modes and comprises a resonance circuit (20) for, in the first mode, increasing an energy supply from a source (4) to the secondary circuit (2) via in-phase resonance circuit voltages and currents and for, in the second mode, not increasing the energy supply to the secondary circuit (2) via not-in-phase resonance circuit voltages and currents and comprises (basic idea) a converter circuit (30) for converting a primary circuit signal into a control signal for the control circuit (40) for bringing the primary circuit (10) into the first mode or into the second mode in dependence of the control signal, according to a zero current switching strategy for reducing losses and electromagnetic interference.
    Type: Application
    Filed: October 9, 2007
    Publication date: February 4, 2010
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N V
    Inventors: Christoph Loef, Thomas Scheel, Christian Hattrup
  • Publication number: 20100008558
    Abstract: The invention relates to an X-ray imaging device (100), particularly a Spectral-CT scanner, that comprises an X-ray source (10) for generating X-radiation with an energy spectrum (P(E,t)) which varies continuously during an observation period (T). In a preferred embodiment, the radiation (X) is attenuated in an object (1) according to an energy-dependent attenuation coefficient ?(E,r), the transmitted radiation is measured by sensor units (22) of a detector (20, 30), and the resulting measurement signal (i(t)) is sampled and A/D converted. This is preferably done by an oversampling A/D converter, for example a ??-ADC. The tube voltage (U(t)) that drives the X-ray source is sampled with high frequency. In an evaluation system (50), these sampled measurement values can be associated with corresponding effective energy spectra (?(E)) to determine the energy dependent attenuation coefficient ?(E,r).
    Type: Application
    Filed: December 11, 2007
    Publication date: January 14, 2010
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N. V.
    Inventors: Christian Baeumer, Roger Steadman Booker, Gereon Vogtmeier, Thomas Scheel, Christoph Loef
  • Publication number: 20090290683
    Abstract: A power supply for generating a high output voltage for supplying an X-ray generator system with at least one X-ray source (17), especially for computer tomography (CT) applications is disclosed, wherein the high output voltage comprises at least two different high output voltage levels (U1; U1±U2) which are fast switchable so that spectral CT measurements can be conducted with one conventional X-ray tube (17). Furthermore, an X-ray tube generator system comprising such a power supply and at least one X-ray tube (17), as well as a computer tomography (CT) apparatus comprising such a power supply is disclosed.
    Type: Application
    Filed: August 21, 2007
    Publication date: November 26, 2009
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N. V.
    Inventors: Christoph Loef, Gereon Vogtmeier, Guenter Zeitler
  • Publication number: 20090161819
    Abstract: Systems and methods for data acquisition in computed tomography (CT) applications are provided. The systems and methods are particularly adapted for scanning and acquiring/processing data in connection with high-power cone-beam CT applications. The electron beam is moved/scanned along the anode surface to multiple focal positions. Data acquisition for a full projection at one focus position and one view angle is achieved by activating each focus position multiple times during the data acquisition for one angle of the gantry. The detector array and associated data processing system are adapted to rapidly switch between the different focus positions during the acquisitions for one view angle and to collect all data belonging to the same projection into the same data set. Adaptive electron optics are utilized to move/scan the electron beam along the anode surface to the various focus positions.
    Type: Application
    Filed: September 16, 2006
    Publication date: June 25, 2009
    Applicant: Koninklijke Philips Electronics N.V.
    Inventors: Astrid Lewalter, Rainer Pietig, Guenter Zeitler, Kai Eck, Christoph Herrmann, Rainer Kiewitt, Christoph Loef, Oliver Muelhens, Carolina Ribbing, Georg Rose, Matthias Simon, Olaf Wischhusen
  • Publication number: 20090002116
    Abstract: The present invention describes a winding for a transformer comprising first (60) and second (70) planar sections which are arranged parallel to each other First (1, e.g., from 602 to 603)) and second (2, e.g., from 703 to 704)) current paths are arranged on the first and second planar sections. The first and second current paths are connected to each other by means of an interconnection (603/703). The first and second current (603/703) paths are respectively angled with respect to a direction along which the first and second planar sections are extending.
    Type: Application
    Filed: December 8, 2006
    Publication date: January 1, 2009
    Applicant: Koninklijke Philips Electronics, N.V.
    Inventors: Christoph Loef, Bernd Ackermann
  • Publication number: 20080297300
    Abstract: Primary (4, 8) and secondary (10) windings are subjected to a significant heat stress during operation of a high voltage transformer. The present invention describes a high voltage transformer which is believed to have good temperature properties. This transformer may have a planar primary winding and a Litz secondary winding. The planar primary winding may abut against a planar face of the core (2) therefore allowing for a good heat exchange between these two elements. The Litz secondary winding and the planar primary winding may be cooled by means of a cooling medium.
    Type: Application
    Filed: December 6, 2006
    Publication date: December 4, 2008
    Applicant: Koninklijke Philips Electronics, N.V.
    Inventors: Bernd Ackermann, Christoph Loef
  • Patent number: 7444530
    Abstract: The invention relates to a standby circuit, an electrical device with a standby circuit, a method for the control of the electrical device and a power supply assembly. Whereas the power supply unit and the control electronics are in permanent operation when conventional devices are in the standby mode and consequently have a high power consumption, the invention proposes a solution for saving energy while retaining convenience of operation by which the power supply unit is switched off in the standby mode. A standby circuit, preferably fed by an energy buffer element, remains active in the standby mode and monitors signal inputs for activation events. When an activation event occurs, the standby circuit switches on the power supply unit.
    Type: Grant
    Filed: February 6, 2002
    Date of Patent: October 28, 2008
    Assignee: NXP B.V.
    Inventors: Carsten Deppe, Peter Luerkens, Thomas Duerbaum, Matthias Wendt, Christoph Loef, Georg Sauerlaender
  • Publication number: 20080218300
    Abstract: The invention relates to a transformer (12) with a planar primary winding and a planar secondary winding. In order to support the heat dissipation during operation, each winding is integrated on a substrate in at least one dedicated PCB (30, 40). The PCBs (30, 40) are separated from each other by a non-ferromagnetic and electrically insulating material (50). The material: (50) transfers heat better than the substrates. The invention relates equally to an apparatus comprising such a transformer (12).
    Type: Application
    Filed: September 19, 2005
    Publication date: September 11, 2008
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS, N.V.
    Inventors: Christoph Loef, Bernd Ackermann
  • Publication number: 20080198634
    Abstract: A resonant DC/DC converter for supplying an output power comprises a switching device (18) for supplying a switched voltage (UWR) to a resonant circuit (20) having a transformer (T). The switched voltage (UWR) is derived from an intermediate circuit voltage (Uz) having a fixed pulse width and frequency so that the zero crossings of the resonant current (Ires) generated in the resonant current are defined. The switching configuration of an inverter circuit (18) is selected by a control device (31) to either increase, decrease or maintain at a substantially constant level the resonant current according to the polarity of the switched voltage, so as to control the output power as required.
    Type: Application
    Filed: April 13, 2006
    Publication date: August 21, 2008
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N. V.
    Inventors: Thomas Scheel, Peter Luerkens, Christoph Loef
  • Publication number: 20080186120
    Abstract: Abstract: The invention relates to a winding arrangement (31) for a planar transformer, in particular for high frequency AC transformation, or for an inductor. In order to provide a winding arrangement (31) for a planar transformer or for an inductor which exhibits the advantages of planar winding arrangements and reduces or avoids the skin-effect, a winding arrangement (31) for a planar transformer, in particular for high frequency AC transformation, or for an inductor is proposed including at least two conduction layers (37, 39), each conduction layer (37, 39) having an inner hole (45) and comprising a plurality of conductor paths (19, 27), which are electrically insulated from each other and which lead from an outer circumference (21) of said conduction layer (37, 39) to an inner circumference (23) of said conduction layer (37, 39) adjacent to said inner hole (45) in a spiral form.
    Type: Application
    Filed: April 28, 2006
    Publication date: August 7, 2008
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS, N.V.
    Inventor: Christoph Loef
  • Publication number: 20080130323
    Abstract: A power supply power supply (30) comprising a DC voltage supply, a control unit and a plurality of high voltage channels (33a-33d) is suggested. Each high voltage channel (33) includes an inverter (IKTV), a resonance circuit, a transformer (TR), and a rectifier (RECT). The resonance circuit cooperates with the inverter (INV). The inverter (INV) is formed by a first switching unit and a second switching unit whereby a voltage of a first polarity can be applied to the resonance circuit in a first switching state, whereas a voltage of a second polarity can be applied to the resonance circuit in a second switching state. The switching states can be switched by the control unit in such a manner that in a first mode of an operation for high output power, the output power can be adjusted by changing the switching frequency in the range of the resonance frequency.
    Type: Application
    Filed: January 26, 2006
    Publication date: June 5, 2008
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS, N.V.
    Inventors: Bernhard Wagner, Bernd Freiheit-Jensen, Christian Vollertsen, Christoph Loef, Cornelius Paul, Frank Mueller, Klaus Hoffmann, Marc Klingelhoeller, Wolfgang Rexhausen
  • Patent number: 7050539
    Abstract: A power supply for X-ray generators which includes at least one inverter (11, 12, 13), at least one transformer (111, 121, 131) and at least one voltage cascade (112, 122, 132) for generating a supply voltage for an X-ray tube (15). In order to increase the output power that can be achieved with a comparatively small weight and a low ripple or output capacitance, the voltage cascade is conceived in respect of its capacitances and the stray inductance of the transformers (111, 121, 131) in such a manner that it can be made to operate in the resonance mode by appropriate control of the inverter. In respect of the properties mentioned it is notably advantageous to integrate a two-phase embodiment or three-phase embodiment with an X-ray system so as to form a compact tank generator.
    Type: Grant
    Filed: December 5, 2002
    Date of Patent: May 23, 2006
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Christoph Loef, Arne Lunding, Heiko Osterholz, Heinz Van Der Broeck