| 摘要 |
1,226,789. Thermistors. GENERAL MOTORS CORP. 12 Dec., 1968 [22 Dec. 1967], No. 59132/68. Heading HlK. A thermistor 10 forming part of a printed circuit consists of a layer 18 of thermistor material sandwiched between upper and lower conductive films 20, 14 on an insulating substrate 12, both films and the layer being formed by printing techniques. The thermistor material consists of 20-60% by weight glass and a mixture of oxides of two or more of cobalt, manganese, copper, iron, chromium and nickel. The substrate is typically of glass or of a ceramic such as alumina, the electrodes of gold, silver-palladium, or gold-platinum and the glass of a low melting point lead-borosilicate glass. The preferred compositions which include specified proportions of cobalt and manganese oxides are applied in the form of a paste with ethyl cellulose and diethylene glycol monobutyl ether to a thickness of 1-10 mils. After application of the layer and electrode films the assembly is fired. The device resistanc is most readily varied by altering the area of upper electrode 20 through compositional and layer thickness changes are also possible. A voltage regulator circuit may be formed by simultaneously printing series or parallel connected resistors on the same substrate. |
