Patents by Inventor Roelf Van Der Wal

Roelf Van Der Wal 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).

  • Patent number: 11735957
    Abstract: A battery includes a first electronic circuit configured to operate in a transfer mode to wirelessly transfer power to a device and to operate in a receive mode to wirelessly receive power from the device. The first electronic circuit also configured to adapt a voltage gain of the first electronic circuit to compensate for a voltage drop between the battery and the device during any one or more of the wireless transfer of power to the device when the battery is operating in the transfer mode and the wireless receipt of power from the device when the battery is operating in the receive mode.
    Type: Grant
    Filed: June 26, 2019
    Date of Patent: August 22, 2023
    Assignee: Koninklijke Philips N.V.
    Inventors: Martijn Gerarda Lambertus Justinus Van Uden, Klaas Jacob Lulofs, Roelf Van Der Wal
  • Publication number: 20210249888
    Abstract: There is provided a battery (100). The battery (100) comprises a first electronic circuit (102) configured to operate in a transfer mode to wirelessly transfer power to a device and to operate in a receive mode to wirelessly receive power from the device. The first electronic circuit (102) is also configured to adapt a voltage gain of the first electronic circuit (102) to compensate for a voltage drop between the battery (100) and the device during any one or more of the wireless transfer of power to the device when the battery (100) is operating in the transfer mode and the wireless receipt of power from the device when the battery (100) is operating in the receive mode.
    Type: Application
    Filed: June 26, 2019
    Publication date: August 12, 2021
    Inventors: Martijn Gerarda Lambertus Justinus VAN UDEN, Klaas Jacob LULOFS, Roelf VAN DER WAL
  • Patent number: 9049395
    Abstract: A processing circuit for an X-ray sensor for collecting at least a first pixel information of a first pixel and a second pixel information of a second pixel is provided. The processing circuit comprises an amplifier (112), a feedback loop (113) and a first collecting device (111). It is provided a compensation for a non-linearity in the pixels or in the pixel circuits (100, 200) by applying an inverse non-linearity (125) in the periphery of the X-ray sensor. A processing circuit (110) may provide a copy of a pixel voltage and/or of a pixel charge. In the case of pixel charge a non-linear characteristic of a pixel capacitance may be compensated.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: June 2, 2015
    Assignee: Trixell
    Inventors: Roelf Van Der Wal, Lex Alving, Walter Ruetten
  • Publication number: 20120080606
    Abstract: A processing circuit for an X-ray sensor for collecting at least a first pixel information of a first pixel and a second pixel information of a second pixel is provided. The processing circuit comprises an amplifier (112), a feedback loop (113) and a first collecting device (111). It is provided a compensation for a non-linearity in the pixels or in the pixel circuits (100, 200) by applying an inverse non-linearity (125) in the periphery of the X-ray sensor. A processing circuit (110) may provide a copy of a pixel voltage and/or of a pixel charge. In the case of pixel charge a non-linear characteristic of a pixel capacitance may be compensated.
    Type: Application
    Filed: June 16, 2010
    Publication date: April 5, 2012
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Roelf Van Der Wal, Lex Alving, Walter Ruetten
  • Patent number: 8134352
    Abstract: A switched mode power supply assembly (1) is described, comprising at least two switched mode power supply units (10i) coupled to each other in parallel; each power supply unit (10i) having an output stage (50i, 60i) capable of selectively operating in a first mode wherein its output signal (IOUT,I) is increasing and operating in a second mode wherein its output signal (IOUT,i) is decreasing; a control device (100) receiving mode switch control signals from all power supply units (10i); wherein the control device (100), if it finds that the actual phase relationship between two power supply units deviates from an optimal phase relationship, is designed to generate synchronising control signals for at least one power supply unit (102), effectively changing the timing of at least one mode switch moment, such that the deviation between the actual phase relationship and said optimal phase relationship is reduced.
    Type: Grant
    Filed: December 3, 2004
    Date of Patent: March 13, 2012
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Roelf Van Der Wal, Jacobus Josephus Leijssen, Josephus Adrianus Maria Van Erp, Machiel Antonius Martinus Hendrix
  • Patent number: 8063581
    Abstract: A drive circuit (1) for driving a load (3) comprises: a power supply (10) for supplying an output current (IL); a controller (20) for controlling the power supply; a current sensor (25) for generating a current sense signal (V25); a controllable switch (30) in series with the output (2a, 2b), the switch being controlled by a mode controller (50); wherein the mode controller in a reduced brightness mode generates its switch control signal (SLC) for the switch for alternatively opening and closing the switch. At the end of a current pulse, an average current value averaged over the pulse duration is calculated, compared with a reference value (VREF), and, if said average value is larger than the reference value, a duration for the next pulse pause is calculated such that an average value averaged over the entire pulse period is equal to the reference value.
    Type: Grant
    Filed: June 20, 2007
    Date of Patent: November 22, 2011
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Roelf Van Der Wal, Zadok Vitalis Socrates Kroeze
  • Publication number: 20090195184
    Abstract: A drive circuit (1) for driving a load (3) comprises: a power supply (10) for supplying an output current (IL); a controller (20) for controlling the power supply; a current sensor (25) for generating a current sense signal (V25); a controllable switch (30) in series with the output (2a, 2b), the switch being controlled by a mode controller (50); wherein the mode controller in a reduced brightness mode generates its switch control signal (SLC) for the switch for alternatively opening and closing the switch. At the end of a current pulse, an average current value averaged over the pulse duration is calculated, compared with a reference value (VREF), and, if said average value is larger than the reference value, a duration for the next pulse pause is calculated such that an average value averaged over the entire pulse period is equal to the reference value.
    Type: Application
    Filed: June 20, 2007
    Publication date: August 6, 2009
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Roelf Van Der Wal, Zadok Vitalis Socrates Kroeze
  • Patent number: 7521910
    Abstract: A method and device for measuring a switched current (IH) comprises: sensing the switched current (IH) with an AC current transformer to obtain an intermediate measuring signal (VHM); receiving a timing signal indicating on and off periods of the switched current (IH); during an off period, generating an auxiliary signal such that the sum of the intermediate measuring signal and the auxiliary signal is equal to zero; and during an on period, adding the intermediate measuring signal and said the auxiliary signal and providing the sum signal as the output measuring signal, the output measuring signal reflecting an actual value of the AC part and the DC part of the switched current (IH).
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: April 21, 2009
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Roelf Van Der Wal, Antonius Jacobus Johannes Werner
  • Publication number: 20090067199
    Abstract: A switched mode power supply assembly (1) is described, comprising at least two switched mode power supply units (10i) coupled to each other in parallel; each power supply unit (10i) having an output stage (50i, 60i) capable of selectively operating in a first mode wherein its output signal (IOUT,I) is increasing and operating in a second mode wherein its output signal (IOUT,i) is decreasing; a control device (100) receiving mode switch control signals from all power supply units (10i); wherein the control device (100), if it finds that the actual phase relationship between two power supply units deviates from an optimal phase relationship, is designed to generate synchronising control signals for at least one power supply unit (102), effectively changing the timing of at least one mode switch moment, such that the deviation between the actual phase relationship and said optimal phase relationship is reduced.
    Type: Application
    Filed: December 3, 2004
    Publication date: March 12, 2009
    Applicant: KONINKLIJKE PHILIPS ELECTRONIC, N.V.
    Inventors: Roelf Van Der Wal, Jacobus Josephus Leijssen, Josephus Adrianus Maria Van Erp, Machiel Antonius Martinus Hendrix
  • Patent number: 7394232
    Abstract: A switched mode power supply assembly that has a plurality of power supply modules cyclically coupled to each other. Each power supply module has a synchronization control module for generating a synchronization control signal for a next neighboring module and for receiving a synchronization control signal from a previous neighboring module to ensure interleaved operation of all modules.
    Type: Grant
    Filed: July 1, 2004
    Date of Patent: July 1, 2008
    Assignee: Koninkljke Philips Electronics N.V.
    Inventors: Machiel Antonius Martinus Hendrix, Roelf Van Der Wal, Jacobus Josephus Leijssen, Josephus Adrianus Maria Van Erp
  • Publication number: 20070103132
    Abstract: A switched mode power supply assembly (1) is described, which comprises a plurality of at least two, power supply modules (10). Each power supply module (10) cyclically coupled to each other. Each power supply module (10i) comprises synchronisation control means for generating a synchronisation control signal for a next neighbouring module (10i+1) and for receiving a synchronisation control signal from a previous neighbouring module (10i+1) in order to ensure interleaved operation of all modules. Low power modules are relatively easily manufacturable in high volume.
    Type: Application
    Filed: July 1, 2004
    Publication date: May 10, 2007
    Inventors: Machiel Hendrix, Roelf Van Der Wal, Jacobus Leijssen, Josephus Van Erp
  • Publication number: 20060158166
    Abstract: In a method for synchronizing a mobile station with the base station in a mobile communication system, a reference-frequency oscillator is re-adjusted. To enable an inexpensive reference-frequency oscillator of simple construction to be used, the frequency variations resulting from a change in the temperature of the mobile station and a change in its location are determined and/or predicted separately. When the frequency variations are large, the mobile station is synchronized with the base station more frequently than when they are small.
    Type: Application
    Filed: July 2, 2004
    Publication date: July 20, 2006
    Inventor: Roelf Van Der Wal
  • Publication number: 20050285814
    Abstract: A driver circuit drives an electroluminescent display (1) which comprises a matrix of display pixels (10) associated with intersections of data electrodes (12) and select electrodes (11). The driver circuit comprises a select driver (2) which supplies a select signal (VS) comprising non-overlapping select pulses (VSP) with a predetermined repetition frequency to a selected one (11?) of the select electrodes (11). The data driver (3) supplies data signals (DS) comprising data pulses (DSP) with the same predetermined repetition frequency to the data electrodes (12). The data pulses (DSP) occur during the select pulses (VSP) for data electrodes (12) of which associated pixels (10) should not produce light. The data pulses (DSP) occur in-between the select pulses (VSP) for data electrodes (12) of which associated pixels (10) should produce light.
    Type: Application
    Filed: July 17, 2003
    Publication date: December 29, 2005
    Applicant: Koninklijke Philips Electronics N.V.
    Inventors: Roelf Van Der Wal, Willibrordus Dijkman, Josephus Erp, Klaas Lulofs
  • Patent number: 6051818
    Abstract: Electric toaster with a first heating element arranged at one side of a toasting compartment and a second heating element arranged at an opposed side of the toasting compartment. The first heating element is divided into two sub-elements. Two diodes and a switch provide the possibility to switch over from a normal two-sided toasting mode to an asymmetric single-sided toasting mode. In the normal mode the switch is closed and the sub-elements receive power only during different half-waves of the mains supply voltage, so that the effective radiant power of the sub-divided first element is equal to the radiant power of the second heating element. In the asymmetric mode the switch is opened and the resistance of the first heating element is greater than the resistance of the second element, as a consequence of which relatively more radiant power is emitted by the first heating element than by the second heating element.
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: April 18, 2000
    Assignee: U.S. Philips Corporation
    Inventors: Roelf Van Der Wal, Jacob H. Botma, Wai H. E. Li, Lawrence S. K. Lai, Peter S. Viet
  • Patent number: 6044002
    Abstract: A flyback converter based on a switcher IC with Pulse Width Modulation control of the switching transistor. The pulse width is controlled by changing the input current at the control input. Under normal operating conditions the voltage at the control input is maintained at a fixed level, which voltage also serves as a supply voltage for the control unit. A charge pump provides extra charge for the smoothing capacitor at the control input when the load would cause the voltage across the smoothing capacitor to collapse below the fixed level, thereby preventing the control unit from entering the auto-restart mode of the switcher IC. In this way the flyback converter can be used as a constant power source for charging rechargeable batteries with a working voltage lower than the nominal operating output voltage of the converter.
    Type: Grant
    Filed: January 22, 1999
    Date of Patent: March 28, 2000
    Assignee: U.S. Philips Corporation
    Inventors: Roelf Van Der Wal, Wilhelmus G.M. Ettes
  • Patent number: 6016261
    Abstract: A switching power supply with synchronous rectification by means of a diode and a parallel-connected electronic switch. By means of a one-shot circuit the electronic switch is driven into conduction during a fixed portion of the time period during which the diode would be conductive without the electronic switch.
    Type: Grant
    Filed: February 1, 1999
    Date of Patent: January 18, 2000
    Assignee: U.S. Philips Corporation
    Inventors: Johannes De Wit, Wilhelmus G. M. Ettes, Roelf Van Der Wal, Jacob H. Botma
  • Patent number: 6006656
    Abstract: A toaster has heating elements (H1, H2) arranged at opposite sides of a product (5) to be toasted. The size of the product to be toasted (5) is detected by a sensor, for example a mechanical sensor (2.1, 2.2, 2.3) or an optical sensor device with a photo-emitter and a photo-receiver. The power delivered by the heating elements (H1, H2) is controlled in dependence on the detected size. Thus, the power consumption of the toaster is adapted to the size of the product to be toasted and overheating of the product is avoided and a constant toasting time is obtained.
    Type: Grant
    Filed: April 2, 1998
    Date of Patent: December 28, 1999
    Assignee: U.S. Philips Corporation
    Inventors: Klaas J. Lulofs, Roelf Van Der Wal
  • Patent number: 5819637
    Abstract: A Toaster having heating elements whose heating area depends on the slice size. A toaster has heating elements (H1, H2) divided into sub-elements (H1A, H1B; H2A, H2B) which can be activated individually. The size of the product to be toasted (5) is detected by means of a sensor, for example a mechanical sensor (2) or an optical sensor device with a photo-emitter and a photo-receiver. The sub-elements are activated selectively in dependence on the detected size. Thus, the power consumption of the toaster is adapted to the size of the product to be toasted and overheating of the product in the proximity of the unused heating area of the heating elements is avoided.
    Type: Grant
    Filed: April 14, 1997
    Date of Patent: October 13, 1998
    Assignee: U.S. Philips Corporation
    Inventors: Jacob H. Botma, Roelf Van Der Wal, Klaas J. Lulofs
  • Patent number: 5758567
    Abstract: A toaster has electrical parts which are energized from a mains voltage. The bread is conveyed to a toasting chamber (4) by means of a lift (6) and a handle (12). In the end position of the handle (12) a main switch (SW5) is turned on, as a result of which the electrical parts can be powered from the mains voltage. The heating elements receive mains voltage via triacs controlled by a microcontroller. After completion of the toasting cycle the microcontroller turns off the heating elements, which precludes burning of the bread, even if the main switch remains in its on-position as a result of a mechanical defect. Subsequently, the microcontroller checks the presence of the mains voltage. In that case a signalling device is activated to warn the user that the mains voltage supply to the toaster has not yet been turned off.
    Type: Grant
    Filed: April 17, 1997
    Date of Patent: June 2, 1998
    Assignee: U.S. Philips Corporation
    Inventors: Roelf Van Der Wal, Jacob H. Botma