Title:
グロープラグ
Document Type and Number:
Japanese Patent JP6996848
Kind Code:
B2
Abstract:
To provide a glow plug capable of restraining a temperature drop in the event of lowering applied voltage for saturating temperature, while ensuring durability and provision of higher heating-up temperature. A rearward coil connected to the rear end of a forward coil containing W or Mo as a main component has a resistance ratio R1 lower than a resistance ratio R2 of the forward coil, where the resistance ratio R1 is the ratio of the resistance of the rearward coil at 1,000°C to the resistance of the rearward coil at 20°C, and the resistance ratio R2 is the ratio of the resistance of the forward coil at 1,000°C to the resistance of the forward coil at 20°C. A tube has a tube forward portion ranging from the forward end of the tube to a position around the axial center of the forward coil and a tube rearward portion ranging from a position around the rear end of the rearward coil to a position around the forward end of the rearward coil. The wall thickness A of the tube forward portion is 0.5 mm or more; the wall thickness B of the tube rearward portion is 0.3 mm or more; and the minimal wall thickness B1 of the tube rearward portion is smaller than the wall thickness A of the tube forward portion.
Inventors:
Makoto Ejiri
Application Number:
JP2017018307A
Publication Date:
January 17, 2022
Filing Date:
February 03, 2017
Export Citation:
Assignee:
Nippon Special Ceramics Co., Ltd.
International Classes:
F23Q7/00
Domestic Patent References:
| JP5608292B2 | ||||
| JP2016075468A | ||||
| JP2004191040A | ||||
| JP2007298265A | ||||
| JP7190361A | ||||
| JP2008235034A | ||||
| JP8278027A | ||||
| JP2006125776A |
Foreign References:
| EP0438097A1 |
Attorney, Agent or Firm:
Patent Service Corporation Shinmei Century
Previous Patent: Package unloading device and textile machine
Next Patent: Manufacturing method of water absorbent
Next Patent: Manufacturing method of water absorbent