Abstract: A device including: a command-generator outputting a drive command signal to a drive unit; a detector outputting a position-detection signal of the drive unit; a drive-current detector outputting a drive-current detection value; a controller receiving the drive command and position-detection signals to generate a drive-force command signal, and supplying the drive current according to the drive-force command signal and the drive-current detection value; a friction-characteristics-estimator receiving a drive force signal and the position-detection signal to output a friction-characteristics estimate value; a temperature-information acquirer outputting a temperature information value; a friction modeling unit having a set reference friction model having temperature-dependent characteristics, and outputting reference friction characteristics based on the temperature information value; and a friction-variation analyzer outputting a friction variation value based on variation of the friction-characteristics estima

Abstract: A device including: a command-generator outputting a drive command signal to a drive unit; a detector outputting a position-detection signal of the drive unit; a drive-current detector outputting a drive-current detection value; a controller receiving the drive command and position-detection signals to generate a drive-force command signal, and supplying the drive current according to the drive-force command signal and the drive-current detection value; a friction-characteristics-estimator receiving a drive force signal and the position-detection signal to output a friction-characteristics estimate value; a temperature-information acquirer outputting a temperature information value; a friction modeling unit having a set reference friction model having temperature-dependent characteristics, and outputting reference friction characteristics based on the temperature information value; and a friction-variation analyzer outputting a friction variation value based on variation of the friction-characteristics estima

Abstract: A configuration in which fixing is performed by inserting a rear end of a lead shaft member into an attachment hole of an external terminal at the rear of a glow plug and crimping an outer peripheral face of the external terminal. The outer peripheral face of a crimp formation region (78) of the external terminal (70) having a polygonal cross section is formed into a crimped portion (79) provided by round crimping toward a circle, and the external terminal (70) is fixed to the rear end (55) of the lead shaft member (50). Due to the configuration obtained from the round crimping of the polygon, plating breaks and the like are not easily produced in the plating layer on the surface of the external terminal.

Abstract: A configuration in which fixing is performed by inserting a rear end of a lead shaft member into an attachment hole of an external terminal at the rear of a glow plug and crimping an outer peripheral face of the external terminal. The outer peripheral face of a crimp formation region (78) of the external terminal (70) having a polygonal cross section is formed into a crimped portion (79) provided by round crimping toward a circle, and the external terminal (70) is fixed to the rear end (55) of the lead shaft member (50). Due to the configuration obtained from the round crimping of the polygon, plating breaks and the like are not easily produced in the plating layer on the surface of the external terminal.

Abstract: An object is to provide a glow plug in which a gap can be prevented from being generated between a ceramic heater and a cylindrical member even at the time of use in an internal combustion engine, etc. so that electrical conduction of the glow plug can be prevented from being lowered. A glow plug includes: a rod-shaped ceramic heater 2; a rod-shaped center pole 5 extending axially so as to electrically connect to the outside; and a cylindrical member 100 having a front end portion 101 bonded to an outer circumferential surface 2a of a rear end side of the ceramic heater 2, and a rear end portion 102 bonded to an outer circumferential surface of a front end side of the center pole 5, the cylindrical member 100 being made by a metal material for electrically connecting one of a pair of lead portions and the center pole 5 to each other, the glow plug characterized in that the cylindrical member 100 has a Vickers hardness of not lower than 200 HV at 25° C.

Abstract: An object is to provide a glow plug in which a gap can be prevented from being generated between a ceramic heater and a cylindrical member even at the time of use in an internal combustion engine, etc. so that electrical conduction of the glow plug can be prevented from being lowered. A glow plug includes: a rod-shaped ceramic heater 2; a rod-shaped center pole 5 extending axially so as to electrically connect to the outside; and a cylindrical member 100 having a front end portion 101 bonded to an outer circumferential surface 2a of a rear end side of the ceramic heater 2, and a rear end portion 102 bonded to an outer circumferential surface of a front end side of the center pole 5, the cylindrical member 100 being made by a metal material for electrically connecting one of a pair of lead portions and the center pole 5 to each other, the glow plug characterized in that the cylindrical member 100 has a Vickers hardness of not lower than 200HV at 25° C.

Abstract: A glow plug comprising: a ceramic heater which houses a heating element defined herein in a tip end side of said ceramic heater, and which elongates in an axial direction; a cylindrical metal shell which has a shaft hole, which houses a rear end portion of said ceramic heater in said shaft hole, and which holds said ceramic heater in said shaft hole directly or via another member; and a center pole including a center-pole rear end portion as defined herein and a center-pole tip end portion as defined herein, said ceramic heater being mechanically rigidly joined to said heater connecting portion, wherein a stress releasing portion in which a diameter is smallest in an area between said heater connecting portion and said center-pole rear end portion is formed in said center pole.

Abstract: A heater including: a rod-shaped ceramic heater including: a ceramic heater body extending in an axial direction and having a heating-element at its leading end portion for generating heat when energized; and first and second energizing lead terminals extending from the heating element and exposed to an outer circumference of a trailing end side of the ceramic heater body; a cylindrical outer cylinder for holding the ceramic heater while protruding a leading end portion and a trailing end portion of the ceramic heater; and a core rod arranged on said trailing end side of the ceramic heater in an axial direction and connected electrically with the first lead terminal, wherein the heater further includes: a ring member including: a ring leading end portion fixed by a tight fitting on an outer circumference of a trailing end side of the ceramic heater and connected electrically with the first lead terminal; and a ring trailing end portion protruding backward from a trailing end of the ceramic heater; and a metal

Abstract: A glow plug comprising: a ceramic heater which houses a heating element defined herein in a tip end side of said ceramic heater, and which elongates in an axial direction; a cylindrical metal shell which has a shaft hole, which houses a rear end portion of said ceramic heater in said shaft hole, and which holds said ceramic heater in said shaft hole directly or via another member; and a center pole including a center-pole rear end portion as defined herein and a center-pole tip end portion as defined herein, said ceramic heater being mechanically rigidly joined to said heater connecting portion, wherein a stress releasing portion in which a diameter is smallest in an area between said heater connecting portion and said center-pole rear end portion is formed in said center pole.

Abstract: A glow plug includes a ceramic heater having a resistance-heating element embedded at its end portion. In order to supply electricity to the resistance-heating element, first and second heater terminals are exposed on the surface of the ceramic heater. First and second terminal rings, which serve as metallic fitting members, are shrink-fitted to the surface of the ceramic heater in such a manner as to cover and be electrically connected to the exposed first and second heater terminals. A metal layer not higher than Ni in ionization tendency is formed on the inner circumferential surface of each of the first and second terminal rings.

Abstract: A heater comprising: a rod-shaped ceramic heater including: a ceramic heater body extending in an axial direction and having a heating element at its leading end portion for generating heat when energized; and first and second energizing lead terminals extending from said heating element and exposed to an outer circumference of a trailing end side of said ceramic heater body; a cylindrical outer cylinder for holding said ceramic heater while protruding a leading end portion and a trailing end portion of said ceramic heater; and a core rod arranged on said trailing end side of said ceramic heater in an axial direction and connected electrically with said first lead terminal, wherein said heater further comprises: a ring member including: a ring leading end portion fixed by a tight fitting on an outer circumference of a trailing end side of said ceramic heater and connected electrically with said first lead terminal; and a ring trailing end portion protruding backward from a trailing end of said ceramic heater;

Abstract: A glow plug includes a ceramic heater having a resistance-heating element embedded at its end portion. In order to supply electricity to the resistance-heating element, first and second heater terminals are exposed on the surface of the ceramic heater. First and second terminal rings, which serve as metallic fitting members, are shrink-fitted to the surface of the ceramic heater in such a manner as to cover and be electrically connected to the exposed first and second heater terminals. A metal layer not higher than Ni in ionization tendency is formed on the inner circumferential surface of each of the first and second terminal rings.