Source: https://patents.google.com/patent/US5243257
Timestamp: 2018-03-21 04:02:42
Document Index: 445903428

Matched Legal Cases: ['art 1', 'art 1', 'art 1', 'art 1', 'art 1', 'art.\n1']

US5243257A - Surge voltage protector - Google Patents
Surge voltage protector Download PDF
US5243257A
US5243257A US07781584 US78158491A US5243257A US 5243257 A US5243257 A US 5243257A US 07781584 US07781584 US 07781584 US 78158491 A US78158491 A US 78158491A US 5243257 A US5243257 A US 5243257A
US07781584
Tha Do-Thoi
H01T1/20—Means for starting arc or facilitating ignition of spark gap
A surge voltage protector having a tubular ceramic part as an insulator, and having metal electrodes soldered onto the end faces thereof. Each electrode is electrically connected in each case to an ignition aid applied at least to the inside wall of the ceramic part. The inside edges of the surfaces joining the ceramic part to the electrodes are each provided with a chamfer whose chamfer angle is 15° to 60° relative to the plane of the joining surfaces. The width projected onto the plane of the joining surface is 0.05 to 0.4 mm.
The invention relates to a surge voltage protector which comprises a tubular ceramic part as an insulator having metal electrodes soldered onto the end faces, each metal electrode being electrically connected in each case to an ignition aid applied at least to the inside wall of the ceramic part.
Surge voltage protectors of the type mentioned are known. A disadvantage of these surge voltage protectors is that the preplacement of solder on the end surfaces of the tubular ceramic part, which preplacement is necessary for a solder joint to the metal electrodes, results in a solder overhang which extends into the interior space of the ceramic part at the inside edge of the joining surface. When the ignition aid, in general made of graphite, is applied to the inside wall of the ceramic part, the application device is damaged by the solder overhang, with the result that in many cases no electrical connection is produced between the ignition aid and the solder preplacement. In addition, the application device has to be realigned, and this is troublesome for an automated ignition aid application cycle.
The object of the invention is to provide a remedy in this connection. This object is achieved by a particular design of the surfaces joining the ceramic part to the metal electrodes, wherein the inside edges of the surfaces joining the ceramic part to the electrodes are each provided with a chamfer whose chamfer angle (α) is 15° to 60° and whose width (b) projected onto the plane of the joining surface is 0.05 to 0.4 mm.
Preferably, the chamfer angle α is 45° and the projected width b of the chamfer is 0.1 mm.
The design of the joining surfaces of the ceramic part avoids a solder overhang in the solder preplacement, which is carried out, for example, by the process disclosed by DE-A 3 824 900, with all its disadvantages for the application of the ignition aid with automated devices.
The invention is explained in greater detail below with reference to the drawings, which represent only one method of embodiment. In the drawings:
FIG. 1 shows the basic construction of a surge voltage protector in section, and
FIG. 2 shows the detail "Z" of FIG. 1 without electrode and with solder preplacement.
The surge voltage protector comprises a tubular ceramic part 1 composed, for example, of Al2 O3 as insulator. Soldered onto the annular end surfaces of the ceramic part 1 are metal electrodes 2. Said metal electrodes are electrically connected in each case to an ignition aid 3 which is applied to the inside wall of the ceramic part. The inside edges of the joining surfaces 4 of the ceramic part 1 are provided with chamfers 5. The angle α of the chamfer relative to the joining surface may be 15° to 60°, preferably 45°, and the width b of the chamfers 5 projected onto the plane of the joining surface 4 may be 0.05 to 0.4 mm, preferably 0.1 mm. The joining surfaces 4 of the ceramic part 1, and also in part on the chamfers 5, are metallized as usual by solder preplacement (solder layer 6) in order to ensure a gastight and firmly adhering solder joint between electrodes and ceramic. The inside space 8 of the surge voltage protector may be filled with a gas, for example a noble gas. 7 indicates the electrical terminals for the electrodes 2. The chamfers 5 on the inside edges of the ceramic part 1 avoid a solder overhang. The metallization 6 ends at the chamfers without reaching the edge of the inside wall of the ceramic part. In addition, the metallization/ceramic transition is almost continuous, with the result that a serviceable ignition aid 3 with electrical connection to the metallization can be applied to the inside wall of the ceramic part.
1. A surge voltage protector comprising a tubular ceramic part as an insulator having end faces, and inside walls, and having metal electrodes soldered onto the end faces, each metal electrode being electrically connected to an ignition aid applied at least to the inside wall of the ceramic part, wherein inside edges of surfaces joining the ceramic part to the metal electrodes are each provided with a chamfer whose chamfer angle (α) is 15° to 60° relative to the plane of said surfaces joining the ceramic part to the electrodes and whose width (b) projected onto said plane of the surfaces joining the ceramic part to the electrodes is 0.05 to 0.4 mm.
2. The surge voltage protector as claimed in claim 1, wherein the chamfer angle (α) is 45° and the projected width (b) is 0.1 mm.
3. The surge voltage protector as claimed in claim 1, wherein said inside walls of the ceramic part form an inside space.
4. The surge voltage protector as claimed in claim 3, wherein said inside space is filled with a noble gas.
5. The surge voltage protector as claimed in claim 1, wherein the surfaces joining the ceramic part to the electrodes are metallized by solder preplacement.
6. The surge voltage protector as claimed in claim 5, wherein said chamfers avoid a solder overhang.
US07781584 1990-10-25 1991-10-23 Surge voltage protector Expired - Fee Related US5243257A (en)
DE19904033927 DE4033927A1 (en) 1990-10-25 1990-10-25 surge arresters
DE4033927 1990-10-25
US5243257A true US5243257A (en) 1993-09-07
ID=6417020
US07781584 Expired - Fee Related US5243257A (en) 1990-10-25 1991-10-23 Surge voltage protector
US (1) US5243257A (en)
EP (1) EP0482542B1 (en)
JP (1) JPH0698459A (en)
CA (1) CA2054121A1 (en)
DE (1) DE4033927A1 (en)
US5491381A (en) * 1991-12-18 1996-02-13 Yazaki Corporation Discharge tube
WO1982001792A1 (en) * 1980-11-13 1982-05-27 Ag Siemens Protection device against discharge overvoltages in a gas with concentric enclosing sleeve
EP0087820A1 (en) * 1982-03-03 1983-09-07 Siemens Aktiengesellschaft Surge arrester with a gas-filled housing
US4491893A (en) * 1982-05-25 1985-01-01 Reliance Electric Company Gas filled surge arrester
US4628399A (en) * 1985-03-27 1986-12-09 Kabushiki Kaisha Sankosha Anti-overvoltage protector
DE3824900A1 (en) * 1988-07-22 1990-01-25 Hoechst Ceram Tec Ag A process for producing a solder coating on metallized ceramic
US4996111A (en) * 1988-07-22 1991-02-26 Hoechst Ceramtec Aktiengesellschaft Process for the production of a solder coating on metallized materials
CA2054121A1 (en) 1992-04-26 application
DE4033927A1 (en) 1992-04-30 application
EP0482542A1 (en) 1992-04-29 application
EP0482542B1 (en) 1995-07-19 grant
JPH0698459A (en) 1994-04-08 application
US3878423A (en) 1975-04-15 Electrical surge arrestor having fail-safe properties
US5577935A (en) 1996-11-26 Coaxial, angular connector for installation on a printed circuit board
US5936822A (en) 1999-08-10 Coaxial surge arrester
US5159158A (en) 1992-10-27 Electrical assembly with insulating collar for coupling sections of weathershed housings
DE3415625A1 (en) 1985-10-31 Electrical detonating element having a desired spark gap
JPH0364979A (en) 1991-03-20 Electrostrictive effect element
US3993387A (en) 1976-11-23 Electrical connector and method of making same
Owner name: HOECHST CERAMTEC AKTIENGESELLSCHAFT
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:DIETRICH, VOLKER;DO-THOI, THA;STINGL, PETER,;REEL/FRAME:005893/0888