Patents Assigned to Oy Helvar
  • Patent number: 5844516
    Abstract: The invention relates to a method and apparatus for wireless remote control. A transmitter (1) with no batteries receives its operating power from a generator (3) which produces electrical energy inductively upon turning or pressing an operating element (4) manually. The same operating element can also be used for determining the direction and degree of control.
    Type: Grant
    Filed: November 7, 1995
    Date of Patent: December 1, 1998
    Assignee: Oy Helvar
    Inventor: Teijo Viljanen
  • Patent number: 5698950
    Abstract: A suppressor for an electronic ballast in a discharge lamp, which is connected between a ballast (A2) and a mains supply, including a supply-voltage rectifier (D2-D5) and a charging capacitor (C6). The suppressor includes at least one energy-storing inductance (L1) and at least two electronic switch elements (Q1, Q2) connected such that, when said switch elements are conducting simultaneously, a current path extends from the positive terminal of the rectifier through said switches and inductance to its negative terminal as well as two diodes (D6, D7) connected such that, when the switches (Q1, Q2) are non-conducting, a current path extends from the negative terminal of the rectifier through said diodes and inductance to its positive terminal.
    Type: Grant
    Filed: November 15, 1995
    Date of Patent: December 16, 1997
    Assignee: OY Helvar
    Inventor: Teijo Viljanen
  • Patent number: 5691604
    Abstract: The invention relates to a method and a circuit system for controlling an appliance used in lighting electronics, especially an electronic ballast or an electronic light controller included in a discharge lamp. An analog or digital type of signal for controlling the operation of an appliance to be controlled is connectable to a common control circuit and. The appliance to be controlled identifies the type of control signal and deciphers the contents of information received thereby on the basis of the signal type.
    Type: Grant
    Filed: November 15, 1995
    Date of Patent: November 25, 1997
    Assignee: Oy Helvar
    Inventor: Teijo Viljanen
  • Patent number: 5552676
    Abstract: The invention relates to a control device for an appliance consuming electric power, especially for the control of lighting or heating. The control element includes a sensor element (V8) for producing a control current or voltage as a result of a light or heat flux received thereby. An amplifier element (V4-V1) boosts the control current of said sensor element (V8) to a sufficient level for controlling one or a plurality of electronic ballasts, which is e.g. a current limiter for a discharge lamp, a regulator for a filament lamp or a heating effect regulator. The electric power required by the amplifier element (V4-V1) of the control device is supplied from said ballast by means of conductors, which also serve as a control line between the control device and the ballast.
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: September 3, 1996
    Assignee: Oy Helvar
    Inventor: Teijo Viljanen
  • Patent number: 5410220
    Abstract: The invention relates to an electronic ballast for a discharge lamp, comprising a drive circuit supplying high-frequency current to the lamp and including two power switches (V1, V2) and control circuits therefor for controlling the power switches, such that the parallel half-waves of the lamp current pass through a first power switch (V1) and the reverse half-waves through a second power switch. Each power switch (V1; V2) is provided with its own, independently operating control circuit and each control circuit is provided with means (R1, R3, R8, R7) for sensing a current passing through and a voltage prevailing across the appropriate power switch (V1; V2) as well as with means (V3; V4) for controllably bringing the appropriate power switch (V1; V2) to a conducting state as a certain voltage prevails thereacross and to a non-conducting state as soon as a current passing therethrough reaches a certain threshold value (Ik; Ikl).
    Type: Grant
    Filed: September 16, 1993
    Date of Patent: April 25, 1995
    Assignee: Oy Helvar
    Inventor: Kari von Hertzen
  • Patent number: 5034660
    Abstract: A method of and apparatus for supplying high frequency alternating current to a fluorescence lamp. For eliminating a so-called striation phenomenon, a direct current component is induced in the high frequency alternating current passing through a lamp (8). The circuit means inducing said direct current component comprise a capacitor (3), connected in series with the lamp and having a diode (4) or the like connected in parallel therewith.
    Type: Grant
    Filed: January 20, 1988
    Date of Patent: July 23, 1991
    Assignee: Oy Helvar
    Inventor: Martti Sairanen
  • Patent number: 4603378
    Abstract: An inverter circuit, comprising a control circuit for improving the switching off of transistors (1 and 2). The control circuit includes a secondary winding (16) for an inductive winding (7) included in a load circuit, said secondary winding being connected in series with a winding (17) for a base control transformer (3) of transistors (1 and 2). The control circuit closes itself by way of a diode (21 or 20) and transistor (1 or 2). Thus, a voltage induced in secondary winding (16) indicating the rate of decrease of the collector current of transistor (1 or 2) improves or accelerates the switching off of transistor (1 or 2) when the hazard of simultaneous conduction of transistors increases e.g. as a result of the reversal of loading state or variation of individual characteristics (such as storage time) of transistors.
    Type: Grant
    Filed: May 2, 1985
    Date of Patent: July 29, 1986
    Assignee: Oy Helvar
    Inventor: Matti Virta
  • Patent number: 4553070
    Abstract: An electronic ballast for a discharge lamp (8) for restricting and stabilizing the lamps current. The ballast comprises a high frequency oscillator for connection to a D.C. supply which consists of two transistors (1,2) connected in series, with a base drive transformer (3) coupled between them to bring the transistors (1,2) into alternating phase operation. A resonance circuit connected in series with the primary winding (4) of the transformer (3), comprises an inductor (7), resonance capacitors (10 and 11) and a capacitor (9) coupled in parallel with the lamp (8). The lamp (8) is, in turn, connected in series with the resonance circuit. In addition, a filter capacitor (c) having a high charging ability is coupled between the terminals of the D.C. supply. The resonance capacitors (10 and 11) are connected in series between the terminals of the D.C.
    Type: Grant
    Filed: July 6, 1982
    Date of Patent: November 12, 1985
    Assignee: Oy Helvar
    Inventors: Martti Sairanen, Matti Virta
  • Patent number: 4456855
    Abstract: Intensity regulator, especially a light regulator which can be adapted to the regulation of the light intensity of both compensated and uncompensated illuminators connected to the alternating-current mains. The regulator comprises one or more switch elements (S1, S2) disposed in a circuit between the mains and an illuminator (L) as well as a control logic circuit (4) for the switch element or elements, said circuit upon the intensity regulation breaking the supply current at least once on each half-cycle when current has been conducted from the O-moment of a half-cycle to the moment according to a set value. On one hand, a problem is the elimination of current peaks produced by voltage differences at a switch-on moment and, on the other hand, the arrangement of a control for the switch elements.
    Type: Grant
    Filed: May 24, 1982
    Date of Patent: June 26, 1984
    Assignee: Oy Helvar
    Inventor: Martti Sairanen
  • Patent number: 4296545
    Abstract: A plurality of hooks, which are of one-piece construction with a casing substantially enclosing a transformer or choke, are engaged by a suspension means which allows the casing, exclusive of the hooks, to be immersed in an impregnating agent. After impregnation, the casing and enclosed choke or transformer are removed from the impregnant and air dried. The hooks and suspension means are not immersed in the impregnating agent.
    Type: Grant
    Filed: March 31, 1980
    Date of Patent: October 27, 1981
    Assignee: Oy Helvar
    Inventors: Esko Lampinen, Kari Kajavo