Abstract: A method of inspecting a glow plug including an inner conductor and an outer disposed member, where the inner conductor includes an electrically conductive heating unit and an energization member to provide an energization path to the heating unit, and the outer disposed member includes a housing for the heating unit and a metal tubular member disposed on an outer periphery of the energization member. The method includes inspecting for the presence of short circuit abnormality based on a value that varies in response to a current that flows through the inner conductor upon application of a high voltage higher than a voltage applied during normal use of the glow plug to the inner conductor for a time short enough to suppress a temperature rise of the inner conductor due to application of the high voltage.

Abstract: There is provided a control device for a glow plug, capable of controlling the energization of a resistance heater of the glow plug by a resistance control process while attaining good resistance control response under cooling of the heater by fuel injection and combustion gas and thereby stably controlling the amount of heat generated by the heater. The resistance heater includes a resistive heating element having a ratio of electrical resistance R1000 at 1000° C. to electrical resistance R20 at 20° C. of 6 or larger, and the glow plug is mounted with at least part of the resistive heating element being protrudingly located in an engine combustion chamber. Under such a condition, the control device controls energization of the resistance heater in a steady control mode to adjust electrical power supplied to the resistance heater in such a manner as to keep a resistance of the heater within a predetermined range.

Abstract: In a glow plug and a spark plug, the surface of a main metal shell is coated with a chromate film in which the quantity of trivalent chrome is 95 wt % or more of the contained chrome components and which has a thickness of 0.2 ?m to 0.5 ?m.

Abstract: To provide a glow plug capable of speedily increasing the temperature, a glow plug mounting structure, and a process for manufacturing the glow plug. In the invention, the glow plug (1) comprises: a cylindrical sheath tube (3) closed at its front end 3S) and opened at its base end (3K); a cylindrical metal shell (5) covering the side of the base end (3K); a heating coil (7) arranged in the sheath tube (3) along the axis thereof and connected at its front end portion (7S) to the front end (3S) of the sheath tube (3); and insulating powder (11) packed in the sheath tube (3). The front end side portion (7H) of the heating coil (7) farther than the foremost end (9T) of the lead member (9) has a coil length not larger than 15 mm in the axial direction from the front end (3S) of the sheath tube (3). The sheath front end portion (3C) enclosing the front end side portion (7H) has an outer diameter not larger than 4.4 mm.

Abstract: There is provided a control device for a glow plug, capable of controlling the energization of a resistance heater of the glow plug by a resistance control process while attaining good resistance control response under cooling of the heater by fuel injection and combustion gas and thereby stably controlling the amount of heat generated by the heater. The resistance heater includes a resistive heating element having a ratio of electrical resistance R1000 at 1000° C. to electrical resistance R20 at 20° C. of 6 or larger, and the glow plug is mounted with at least part of the resistive heating element being protrudingly located in an engine combustion chamber. Under such a condition, the control device controls energization of the resistance heater in a steady control mode to adjust electrical power supplied to the resistance heater in such a manner as to keep a resistance of the heater within a predetermined range.

Abstract: A glow plug energization control apparatus includes a unit for performing an energization control so that a sheath heater is quickly heated when a key switch is put in an on position, a unit for performing, subsequently to this, an energization control to prevent a drop in temperature of the sheath heater, a unit for performing, when the key switch is put in the start position during the energization control, an energization control to prevent a drop in temperature of the sheath heater during its period, and a unit for performing, after the engine is started, an energization control to keep the sheath heater at a second target temperature.

Abstract: A glow plug energization control apparatus includes a unit for performing an energization control so that a sheath heater is quickly heated when a key switch is put in an on position, a unit for performing, subsequently to this, an energization control to prevent a drop in temperature of the sheath heater, a unit for performing, when the key switch is put in the start position during the energization control, an energization control to prevent a drop in temperature of the sheath heater during its period, and a unit for performing, after the engine is started, an energization control to keep the sheath heater at a second target temperature.

Abstract: A glow plug 1 includes a metallic tube 3 having a closed distal end and extending axially, a rod-like insulator 14 disposed within the metallic tube 3 so as to form a clearance therebetween, a coil member 5 disposed so as to encircle an outer circumferential surface of the insulator 14, and insulating powder 15 charged into the metallic tube 3 so as to fill the interior of the metallic tube 3. The insulator 14 is formed of a material having thermal conductivity lower than that of the insulating powder 15. By rendering the thermal conductivity within the coil member 5 lower than the thermal conductivity in a region between the coil member 5 and the metallic tube 3, conduction of heat generated by the coil member 5 to the inside of the coil member 5 is suppressed, so that the heat is effectively conducted to the metallic tube 3.

Abstract: To provide a glow plug capable of speedily increasing the temperature, a glow plug mounting structure, and a process for manufacturing the glow plug.

Abstract: In a glow plug and a spark plug, the surface of a main metal shell is coated with a chromate film in which the quantity of trivalent chrome is 95 wt % or more of the contained chrome components and which has a thickness of 0.2 &mgr;m to 0.5 &mgr;m.

Abstract: In a glow plug and a spark plug, the surface of a main metal shell is coated with a chromate film in which the quantity of trivalent chrome is 95 wt % or more of the contained chrome components and which has a thickness of 0.2 &mgr;m to 0.5 &mgr;m.

Abstract: A glow plug 1 includes a sheathed heater 3 and a metallic shell 2. The sheathed heater 3 is configured such that a resistance wire coil 3b having a heating coil portion 30b and an insulating MgO powder 3d are placed in a sheath 3a and such that a bar electrode 3c is inserted into the sheath 3a. The heating coil portion 30b is formed of a coil base material 31b and a coating layer 32b, which covers the surface of the coil base material 31b. The coating layer 32b is formed of Pt, Pd, Rh, or an alloy of two or more of Pt, Pd, and Rh.

Abstract: A heater 1 has a seal structure formed by inserting a shaft-like member 4 into a stepped bore 8 formed in a tubular member 2, and setting an O-ring 16 on an upper surface of a stepped portion of the stepped bore 8, a clearance 15 between the shaft-like member 4 and tubular member 2 being thereby sealed with this seal structure. A seal region 17 is formed on the upper surface of the stepped portion of the stepped bore 8, and a conical introduction port portion 18 extending divergently in the rearward direction from the seal region toward an opening of the stepped bore 8 is provided. Moreover, a cone angle &agr; of the introduction port portion 18 with respect to an axis L of the tubular member 2 is set to not larger than 35°.

Abstract: A heater 1 has a seal structure formed by inserting a shaft-like member 4 into a stepped bore 8 formed in a tubular member 2, and setting an O-ring 16 on an upper surface of a stepped portion of the stepped bore 8, a clearance 15 between the shaft-like member 4 and tubular member 2 being thereby sealed with this seal structure. A seal region 17 is formed on the upper surface of the stepped portion of the stepped bore 8, and a conical introduction port portion 18 extending divergently in the rearward direction from the seal region toward an opening of the stepped bore 8 is provided. Moreover, a cone angle &agr; of the introduction port portion 18 with respect to an axis L of the tubular member 2 is set to not larger than 35°.

Abstract: In a glow plug and a spark plug, the surface of a main metal shell is coated with a chromate film in which the quantity of trivalent chrome is 95 wt % or more of the contained chrome components and which has a thickness of 0.2 &mgr;m to 0.5 &mgr;m.

Abstract: In a glow plug and a spark plug, the surface of a main metal shell is coated with a chromate film in which the quantity of trivalent chrome is 95 wt % or more of the contained chrome components and which has a thickness of 0.2 &mgr;m to 0.5 &mgr;m.

Abstract: The invention provides a glow plug with an electric resistor made of a material comprising 20 to 60% by weight nickel and less than 5% by weight iron and the balance of cobalt and unavoidable impurities. The glow plug pf the invention attains an excellent quick heating ability, a self-temperature control function, high oxidation resistance, long durability and good workability.

Abstract: The invention provides a glow plug with an electric resistor made of a material comprising 20 to 60% by weight nickel and less than 5% by weight iron and the balance of cobalt and unavoidable impurities. The glow plug of the invention attains an excellent quick heating ability, a self-temperature control function, high oxidation resistance, long durability and good workability.

Abstract: In a glow plug and a spark plug, the surface of a main metal shell is coated with a chromate film in which the quantity of trivalent chrome is 95 wt % or more of the contained chrome components and which has a thickness of 0.2 &mgr;m to 0.5 &mgr;m.

Abstract: In a glow plug and a spark plug, the surface of a main metal shell is coated with a chromate film in which the quantity of trivalent chrome is 95 wt % or more of the contained chrome components and which has a thickness of 0.2 &mgr;m to 0.5 &mgr;m.