Disclosed is a heater including: an insulating base; a heating element buried in the insulating base and formed of a first linear section, a second linear section provided in parallel with the first linear section, and a folded section configured to connect the first linear section and the second linear section; a first lead buried in the insulating base and connected to the first linear section; and a second lead buried in the insulating base and connected to the second linear section. The first linear section is inclined relative to the first lead.

A ceramic heater wherein in at least one cross section of the ceramic heater orthogonal to the axial direction, a first resistor cross section has no protrusion on a first inner portion of the contour of a first resistor cross section, and has two or more protrusions on a first outer portion of the contour of the first resistor cross section and a method of manufacturing the ceramic heater.

A ceramic glow pug has a structure in which a portion of an embedded resistor is exposed on a portion of a substrate and forms an exposed surface of an electrode taking-out portion. The resistor formed of an electrically conductive ceramic is embedded in the substrate formed of an electrically insulating ceramic, and a portion of the resistor is exposed on the surface of the substrate and has an exposed surface. The exposed surface and the embedded portion differ in stress acting on the substrate, which may decrease the breakage resistance in the vicinity of the electrode taking-out portion. The shape of the exposed surface is such that dimensions, in the axial and circumferential directions, fall within a range of 1.0 mm to 1.8 mm.

The present disclosure is directed to a heater including: a resistor including a heat-generating portion; a lead joined to an end portion of the resistor; and an insulating base covering the resistor and the lead. The heater includes a connection portion in which the resistor and the lead overlap each other in a direction perpendicular to an axial direction of the lead, and a boundary between the resistor and the lead has a curved shape when the connection portion is seen in a cross section perpendicular to the axial direction.

A configuration and manufacturing steps of a ceramic heater-type glow plug are simplified when compared to a related art, and a fracture therein is prevented.

A ceramic heater-type glow plug that includes a ceramic heater, and a metallic outer cylinder, one end side of which holds the ceramic heater and the other end side of which is inserted in and fixed to an inner hole of a housing.

A ceramic heater includes a substrate containing a ceramic, and a resistor containing another ceramic and embedded in the substrate. The resistor includes two lead portions, a joint portion that connects the two lead portions, an electrode portion formed integrally with at least one lead portion, having one end portion connected to the one lead portion, extending in a direction crossing an axis of the one lead portion, and having the other end portion exposed at the surface of the substrate. In a cross section of the electrode portion taken along an imaginary plane passing through the axis of the one lead portion and parallel to an extending direction of the electrode portion, 0.1A/B0.8 is satisfied, where A is the length of the other end portion parallel to the axis, and B is the length of the one end portion parallel to the axis.

A ceramic heater includes a substrate containing a ceramic, and a resistor containing another ceramic and embedded in the substrate. The resistor includes two lead portions, a joint portion connecting the two lead portions, and an electrode portion formed integrally with at least one lead portion and extending in a direction crossing an axial line of the one lead portion. The electrode portion has a base end portion connected to the one lead portion, a distal end portion exposed at an outer surface of the substrate, and a connection portion disposed between the base end portion and the distal end portion and connecting the base end portion and the distal end portion together. A cross section of either the base end portion, the distal end portion, and the connection portion has an imaginary plane perpendicular to an extension direction of the electrode portion and has a streamline shape.

A heater of the disclosure includes: an insulating base including a rod-shaped portion; a heat generating resistor located inside the insulating base; a fixing member which is cylindrical, wherein the insulating base is inserted into the fixing member; and a spacer which is belt-shaped, located between the rod-shaped portion and the fixing member, and surrounds the rod-shaped portion in a circumferential direction. The spacer includes a first end and a second end which face the first end.

An electrode-embedded ceramic structure includes: a ceramic shaft, wherein an electrode is disposed on an outer circumference thereof; and a ceramic tube housing the ceramic shaft therein and coupled to the ceramic shaft. In this electrode-embedded ceramic structure, spaces are provided locally between the ceramic shaft and the ceramic tube.

A high-voltage ceramic electric heating element, comprising a body (9), the body (9) being hollow and having an open trailing portion, and a notch (7) being provided on the body (9) in the axial direction and extending through from left to right; a temperature control region (8) is provided at a position on an outer resistance layer (2) of the body (9), and the cross sectional area of the temperature control region (8) is smaller than the cross sectional area of the body (9). Using the high-voltage ceramic electric heating element can improve the ignition reliability and the service life.