Patents by Inventor Jan DE Ridder

Jan DE Ridder 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).

  • Arrangement including a metal vapor discharge tube provided with at least two internal electrodes
    Patent number: 4636691
    Abstract: An arrangement including a frequency converter (4) and a discharge lamp (10) connected thereto wherein the frequency converter (4) is of a type whose output frequency is at least 80 kHz, while the lamp is a low-pressure sodium vapor discharge lamp. This lamp supply system provides a high luminous efficacy for the lamp.
    Type: Grant
    Filed: December 16, 1983
    Date of Patent: January 13, 1987
    Assignee: U.S. Philips Corporation
    Inventors: Rolf E. de Man, Jan de Ridder, Leo M. Sprengers, Jozef I. C. Peeters
  • Apparatus for the provision of vertical drain channels in grass, fields, meadows etc.
    Patent number: 4422510
    Abstract: A frame is provided journalling a rotary shaft having a lever system for rectilinearly driving at least one set of pins into and out of the ground. The lever system has a pair of substantially parallel spaced rods connected pivotally at one end to the set of pins and at the other end pivotally to the frame and offset from each other. The lower rod is extendible in length when the pins are placed under load and automatically resumes its normal length when the load is removed.
    Type: Grant
    Filed: March 6, 1981
    Date of Patent: December 27, 1983
    Assignee: Redexim Holding S.A.
    Inventor: Arie-Jan de Ridder
  • Electric incandescent lamp
    Patent number: 4331901
    Abstract: In the electric incandescent lamps having an infrared radiation-reflecting filter which is pervious to visible light, the efficiency can be increased by adapting the geometry of the filter and the geometry of the filament to each other. According to the invention, the filter comprises a major portion of a prolate ellipsoid of revolution and a cylindrical filament extends between the foci thereof, the distance between focal points being from 1-2 times the length of the filament.
    Type: Grant
    Filed: April 14, 1980
    Date of Patent: May 25, 1982
    Assignee: U.S. Philips Corporation
    Inventors: Bertus de Vrijer, Leonard C. H. Eijkelenboom, Jan de Ridder
  • High-pressure discharge lamp
    Patent number: 4117369
    Abstract: A high-pressure discharge lamp having a hydrogen getter in a metal envelope of which only a part consists of a hydrogen-permeable metal. The getter is arranged in the lamp in such manner that the hydrogen-permeable part of the envelope faces the discharge.
    Type: Grant
    Filed: September 20, 1977
    Date of Patent: September 26, 1978
    Assignee: U.S. Philips Corporation
    Inventors: Gijsbert Kuus, Adriaan Jan DE Ridder
  • Gas-filled electric incandescent lamp having a cylindrical envelope and an axially arranged filament body
    Patent number: 3956659
    Abstract: In a two-pinch halogen lamp having an axial filament and an envelope diameter of less than 3.5 mm the envelope diameter is chosen as a function of the envelope and filament temperature, the coil diameter and the filling pressure.
    Type: Grant
    Filed: April 26, 1974
    Date of Patent: May 11, 1976
    Assignee: U.S. Philips Corporation
    Inventors: Friedrich Hermann Raymond Almer, Jan DE Ridder, Germain Remi T'Jampens