Patents by Inventor Axel Schnell

Axel Schnell 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: 4692289
    Abstract: A voltage-dependent resistor having a low operational field strength with a ceramic sintered body on the basis of a polycrystalline alkaline earth metal titanate doped with a small quantity of a metal oxide so as to produce an N-type conductivity, in which the sintered body comprises at its grain boundaries insulating layers formed by in-diffusion of at least a metal oxide or at least a metal oxide compound and comprises of an alkaline earth metal titanate having Perowskite structure of the general formula:(A.sub.1-x Ln.sub.x)TiO.sub.3 .multidot.yTiO.sub.2 or A(Ti.sub.1-x Me.sub.x)O.sub.3 .multidot.yTiO.sub.2wherein: A=alkaline earth metal; Ln=rare earth metal; Me=metal having a valency of 5 or more; 0.0005<x<solubility limit in the Perowskite phase; y=0.001 to 0.02.
    Type: Grant
    Filed: July 11, 1985
    Date of Patent: September 8, 1987
    Assignee: U.S. Philips Corporation
    Inventors: Detlev Hennings, Axel Schnell, Herbert Schreinemacher
  • Patent number: 4606116
    Abstract: A non-linear resistor having an operational field strength which optionally is formed as a VDR- or as an NTC-resistor having a ceramic sintered body on the basis of a polycrystalline alkaline earth metal titanate doped with a small quantity of a metal oxide so as to produce an N-type conductivity, in which the sintered body comprises at its grain boundaries insulating layers formed by re-oxidation of the sintered body and consists of an alkaline earth metal titanate having a Perowskite structure of the general formula(A.sub.1-x Ln.sub.x)TiO.sub.3.yTiO.sub.2 or A(Ti.sub.1-x Me.sub.x)O.sub.3.yTio.sub.2,wherein: A=alkaline earth metal; Ln=rare earth metal; Me=metal having a valency of 5 or more; 0.0005<x<solubility limit in the Perowskite phase; y=0.001 to 0.02.
    Type: Grant
    Filed: July 11, 1985
    Date of Patent: August 19, 1986
    Assignee: U.S. Philips Corporation
    Inventors: Detlev Hennings, Axel Schnell, Herbert Schreinemacher
  • Patent number: 4581159
    Abstract: A voltage-dependent resistor having a low operational field strength with a ceramic sintered body on the basis of a polycrystalline alkaline earth metal titanate doped with a small quantity of a metal oxide so as to produce an N-type conductivity, in which the sintered body comprises at its grain boundaries insulating layers formed by in-diffusion of at least a metal oxide or at least a metal oxide compound and comprises of an alkaline earth metal titanate having Perowskite structure of the general formula:(A.sub.1-x Ln.sub.x)TiO.sub.3.yTiO.sub.2 or A(Ti.sub.1-x Me.sub.x)O.sub.3.yTiO.sub.2wherein: A=alkaline earth metal; Ln=rare earth metal; Me=metal having a valency of 5 or more; 0.0005<x<solubility limit in the Perowskite phase; y=0.001 to 0.02.
    Type: Grant
    Filed: May 28, 1982
    Date of Patent: April 8, 1986
    Assignee: U.S. Philips Corporation
    Inventors: Detlev Hennings, Axel Schnell, Herbert Schreinemacher
  • Patent number: 4551269
    Abstract: A non-linear resistor having an operational field strength which optionally is formed as a VDR- or as an NTC-resistor having a ceramic sintered body on the basis of a polycrystalline alkaline earth metal titanate doped with a small quantity of a metal oxide so as to produce an N-type conductivity, in which the sintered body comprises at its grain boundaries insulating layers formed by re-oxidation of the sintered body and consists of an alkaline earth metal titanate having a Perowskite structure of the general formula(A.sub.1-x Ln.sub.x)TiO.sub.3.yTiO.sub.2 or A(Ti.sub.1-x Me.sub.x)O.sub.3.yTiO.sub.2,wherein: A=alkaline earth metal; Ln=rare earth metal; Me=metal having a valency of 5 or more; 0.0005<.times.<solubility limit in the Perowskite phase; y.times.0.001 to 0.02.
    Type: Grant
    Filed: May 28, 1982
    Date of Patent: November 5, 1985
    Assignee: U.S. Philips Corporation
    Inventors: Detlev Hennings, Axel Schnell, Herbert Schreinemacher
  • Patent number: 4533849
    Abstract: A bistable ceramic deflection element includes an assembly of two ceramic plates of a ferroelectric ceramic material which can be easily polarized and which has a low coercive field strength, one plate thereof being polarized so that the deflection element is deflected. The other plate is not polarized. The depolarization of the polarized plate can be performed simultaneously with the polarization of the plate non-polarized thus far, because the interchanging of the polarization condition can be simply performed by briefly applying a direct voltage via two extreme electrodes, provided on the plates. The direct voltage causes polarization of the plate not polarized thus far.
    Type: Grant
    Filed: October 24, 1983
    Date of Patent: August 6, 1985
    Assignee: U.S. Philips Corporation
    Inventor: Axel Schnell
  • Patent number: 4417227
    Abstract: A lead germante phase, (Pb.sub.5 Ge.sub.3 O.sub.11) is added to a ceramic sintered body formed from a polycrystalline alkaline earth metal titanate which has been doped with a small quantity of metal oxide to produce a N-type conductivity. A thin insulating layer of this germante is formed at the grain boundaries of the polycrystalline semiconducting alkaline earth metal titanate because of the formation of a liquid phase during sintering. Thus, the varistor effect is immediately available in the overall volume of the resistance body and need not first be induced by means of a forming procedure, as is the case for known resistors formed from N-doped barium titanate.
    Type: Grant
    Filed: May 13, 1981
    Date of Patent: November 22, 1983
    Assignee: U.S. Philips Corporation
    Inventors: Detlev Hennings, Axel Schnell, Herbert Schreinemacher
  • Patent number: 4359892
    Abstract: A surface testing apparatus includes a bilaminar ceramic flexure element provided with means for generating a voltage which is proportional to the deflection of the flexure element. This voltage is compared with a reference voltage. After amplification the difference voltage is applied to the flexure element so that the applied force remains constant, independently of the deflection.
    Type: Grant
    Filed: December 15, 1980
    Date of Patent: November 23, 1982
    Assignee: U.S. Philips Corporation
    Inventors: Axel Schnell, Heinrich Oepen