Patents by Inventor Tomas Jonsson

Tomas Jonsson 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: 6499100
    Abstract: When decoding instructions of a program to be executed in a central processing unit comprising pipelining facilities for fast instruction decoding, part of the decoding is executed or the decoding in pipelining units is prepared in a remapping unit during loading a program into a program or primary memory used by the central processor, the remapping or predecoding operation resulting in operation codes which can be very rapidly interpreted by the pipelining units of the central processor. Thus, the operation code field of an instruction is changed to include information on e.g., instruction length, jumps, parameters, etc., this information indicating the instruction length, whether it is a jump instruction or has a parameter etc. respectively, in a direct way that allows the use of simple combinatorial circuits in the pipelining units.
    Type: Grant
    Filed: May 30, 2000
    Date of Patent: December 24, 2002
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Dan Halvarsson, Tomas Jonsson, Per Holmberg
  • Patent number: 6457145
    Abstract: For fault testing in a digital system, a processor unit is made available from other activities and the logical units to be tested are set to a predetermined state. An output response analyze is activated and the processor unit generates a set of stimuli, influencing the appropriate logical units. The output response analyzer collects responses to the stimuli at different nodes in the digital system and creates signatures from them. The signals are verified and if a fault is noticed, this error is noticed. The present state of the processor and other logical units are stored in a storage device prior to the test and recovered after the testing is finished. This fault testing can be performed both at chip and board levels, and on systems with several units.
    Type: Grant
    Filed: July 16, 1999
    Date of Patent: September 24, 2002
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Per Anders Holmberg, Dan Olov Halvarsson, Tomas Jonsson
  • Patent number: 6404656
    Abstract: Thyristor-controlled series capacitor equipment (CEQ), intended for connection between an ac network (NET) and a converter (CONV), connected thereto, for conversion between alternating current ((IT) and high-voltage direct current (Id), with a controllable semiconductor valve (TYSW), has control equipment with control means (32) which, in dependence on a synchronization signal (&PHgr;SYNC), form firing pulses (TP1,TP2) for control of the semiconductor valve. The converter has a control device (CTR1) which forms a control-angle order (&agr;-ORD) for phase-angle control of the converter, related to the phase position for a voltage (U12) at a chosen connection point (J2).
    Type: Grant
    Filed: July 11, 2001
    Date of Patent: June 11, 2002
    Assignee: ABB AB
    Inventors: Tomas Jonsson, Lennart Angquist
  • Patent number: 6361148
    Abstract: A direct electrostatic printing device and method print an image to an information carrier with improved alignment between printed part images from two or more print stations. The improved alignment is based on a basic mechanical alignment with a basic accuracy between the print stations which is improved by an electronic alignment of the corresponding bitmaps. The electronic alignment is made possible by the capability of at least one print station to print at least one additional dot in relation to the corresponding bitmap. The minimum number of additional dots being dependent on the attained basic accuracy of the basic mechanical alignment.
    Type: Grant
    Filed: June 15, 1999
    Date of Patent: March 26, 2002
    Assignee: Array Printers AB
    Inventors: Tomas Jonsson, Anders Ingelhag, Göran Nybom, Henrik Gustavsson, Krister Uvnäs, Lennart Sjöstedt, Lennart Thålin
  • Patent number: 6361147
    Abstract: A direct electrostatic printing device and method print an image to an information carrier with increased density during printing. This is attained by measuring undesired image density variations in a direction parallel to the relative movement between an image receiving member and a printhead structure. The density variations are caused by distance variations between the printhead structure and a pigment particle source during printing, which at least in part is caused by a relative movement between at least a part of the pigment particle source and the printhead structure. A control unit is arranged to control the transport of pigment particles in such a way as to compensate for these undesired image density variations during printing, thus attaining a percepted uniform image density along a printed image for a specific desired image density.
    Type: Grant
    Filed: June 15, 1999
    Date of Patent: March 26, 2002
    Assignee: Array Printers AB
    Inventor: Tomas Jonsson
  • Patent number: 6102525
    Abstract: A direct electrostatic printing device and method for printing an image to an information carrier with increased density harmonization. By continuously keeping track of the amount of pigment particles each aperture has available and thereafter using this information and the desired print density to control the control electrodes of the individual apertures, a harmonization of the printed density from different apertures is attained.
    Type: Grant
    Filed: March 19, 1998
    Date of Patent: August 15, 2000
    Assignee: Array Printers AB
    Inventor: Tomas Jonsson
  • Patent number: 6082850
    Abstract: A direct electrostatic printing device and method for printing an image to an information carrier with improved harmonization of the printed density from a plurality of rows of apertures. The harmonization of the printed density from apertures from different rows is accomplished by an improved method of controlling the amount of pigment particles transported through the apertures of each row. The method takes into account which row the aperture belongs to and how the rows are positioned in relationship to the pigment particle feed.
    Type: Grant
    Filed: March 19, 1998
    Date of Patent: July 4, 2000
    Assignee: Array Printers AB
    Inventor: Tomas Jonsson
  • Patent number: 6081283
    Abstract: A direct electrostatic printing device and method for printing an image to an information carrier with increased density harmonization. This is attained by measuring the behavior of the apertures and subsequently adjusting the control parameters of at least the diverging apertures. The measurement of the behaviour of the apertures is suitably performed by scanning a known print sample with a predetermined density. The scanned values are inverted around a predetermined value for which no compensation is done to create a compensation function. At least the apertures which have a behavior which diverges from a predetermined behaviour are compensated according to the compensation function, thereby enabling an increased density harmonization. The compensation function can preferably be signal processed by, for example, a low pass filtering.
    Type: Grant
    Filed: March 19, 1998
    Date of Patent: June 27, 2000
    Assignee: Array Printers AB
    Inventor: Tomas Jonsson
  • Patent number: 5701239
    Abstract: An installation for transmission of electric power by means of high-voltage direct current has two converters (SRI, SRII), each of which is connected to an alternating-voltage network (NI, NII) and which are connected to each other through a dc connection (L). One converter (SRI) is controlled as a rectifier and another converter (SRII) is controlled as an inverter. One converter (SRI) is current-controlling and another converter (SRII) is voltage-controlling. The installation has means (VARC.sub.rect) adapted, at such a change of the control angle (.alpha..sub.rect) of the current-controlling converter (SRI) that the angle reaches a limit of a predetermined interval (.alpha..sub.max nom rect -.alpha..sub.min nom rect) to control, by means of the voltage-controlling converter (SRII), the direct voltage (Ud) of the transmission in such a way that said change is limited.
    Type: Grant
    Filed: February 8, 1996
    Date of Patent: December 23, 1997
    Assignee: Asea Brown Boveri AB
    Inventors: Per-Erik Bjorklund, Tomas Jonsson, Lars-Erik Juhlin
  • Patent number: 5694306
    Abstract: Control equipment (CE1) generates an ordered value (AOL) of a control angle (.alpha.) in dependence on a limiting signal (AMINL, AMAXL), capable of being influenced, for a converter included in a series-compensated converter station. A calculating value (AFIRL) of a control angle is calculated continuously according to a predetermined relationship (H'1, H'2) which at least approximately imitates a relationship according to which, at a firing voltage (Ufir) for the valves of the converter equal to a preselected value (Uvref), said control angle is a function (G'0) of a current (Id1) and a voltage (Un1) in the converter station and the limiting signal is formed in dependence on the calculating value. (FIG.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: December 2, 1997
    Assignee: Asea Brown Boveri AB
    Inventors: Per-Erik Bjorklund, Tomas Jonsson
  • Patent number: 5666277
    Abstract: A series-compensated converter station in an installation for transmission of high-voltage direct current is connected to an alternating-voltage network (N) with three phases (A, B, C, respectively). The converter station comprises at least two direct-voltage series-connected six-pulse converter bridges (SR1, SR2, respectively), a three-phase transformer coupling with two secondary windings (SW1, SW2, respectively), and a star-connected primary winding (PW) with a neutral point (NP) connected to ground as well as a series capacitor unit (CN) for each one of the three phases. Each one of the converter bridges is connected to a respective secondary winding and the primary winding is connected to the alternating-voltage network via the series-capacitor units. The transformer coupling exhibits a high impedance to zero-sequence currents through the primary winding of the transformer coupling.
    Type: Grant
    Filed: September 11, 1995
    Date of Patent: September 9, 1997
    Assignee: Asea Brown Boveri AB
    Inventors: Per-Erik Bjorklund, Tommy Holmgren, Tomas Jonsson, Urban strom
  • Patent number: 5657213
    Abstract: Control equipment (CE2) generates an ordered value (AOL) of a control angle (.alpha.) in dependence on a limiting signal (AMAXL), capable of being influenced, for a converter included in a series-compensated converter station. A calculating value (AMARG) of a control angle is calculated continuously according to a predetermined relationship (M0, M1, M2, M3) which at least approximately resembles a relationship according to which, at a commutating margin (.gamma..sub.m) equal to a preselected value (.gamma..sub.p), said control angle is a function (F0) of a current (Id2) and a voltage (Un2) in the converter station and the limiting signal is formed in dependence on the calculating value.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: August 12, 1997
    Assignee: Asea Brown Boveri AB
    Inventors: Per-Erik Bjorklund, Tomas Jonsson
  • Patent number: 5627735
    Abstract: A series-compensated converter station included in an installation for transmission of high-voltage direct current comprises a converter (SR1, SR2) with at least one 6-pulse bridge (BR). Via series capacitors (SCR, SCS, SCT) the 6-pulse bridge is connected to a three-phase alternating-voltage network (N1, N2) with a fundamental frequency (f.sub.01, f.sub.02). Control equipment (CE1, CE2) generates an ordered value (AOL) of a control angle (.alpha.) for valves (V1-V6) included in the 6-pulse bridge in dependence on a limiting signal (AMAXL) capable of being influenced. An amplitude signal (AMPL) is formed which corresponds to the amplitude (C.sub.1) for a component (C.sub.1 cos(2.pi.f.sub.0 t+.phi..sub.1)) of the fundamental frequency in the direct voltage (Udb) of the 6-pulse bridge and a compensating signal (ACOMP) is continuously calculated in dependence on a sensed voltage (Un1, Un2) at the converter station and on the amplitude signal.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: May 6, 1997
    Assignee: Asea Brown Boveri AB
    Inventors: Per-Erik Bjorklund, Tomas Jonsson, Lars-Erik Juhlin
  • Patent number: 5621626
    Abstract: An installation for transmission of high-voltage direct current comprises a first and a second converter (SR1, SR2, respectively), each one controlled by a separate piece of control equipment (CE1, CE2, respectively). Each one of the pieces of control equipment comprises a current controller (CC). The current controller of the second converter is supplied with a second current reference value (IOL2) and a current margin (IOM). The control equipment of the second converter comprises a function-forming member (11), which in dependence on an applied measured value (UD) of the direct voltage forms the current margin such that, when the direct voltage exceeds a first preselected voltage level (Udf), it assumes a first value (IOMf) and, when the direct voltage is lower than the first voltage level, it assumes a second value (IOMs), the magnitude of the second value being greater than the magnitude of the first value.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: April 15, 1997
    Assignee: Asea Brown Boveri AB
    Inventors: Per-Erik Bjorklund, Tomas Jonsson, Lars-Erik Juhlin