Ngk Spark Plug Company, Limited

Chiaki Kumada

Wataru Matsutani

Hiroaki Nasu

Katsunari Ninomiya

Takayuki Sakurai

Shunsuke Gotou

Shunsuke Gotoh

Hiroyuki Kimata

Naoto Terada

Shunsuke Goto

Yukifumi Chiba

Seigo Muramatsu

Hisashi Higuchi

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&#xb0; C. to electrical resistance R20 at 20&#xb0; 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.

Controller and glow plug for controlling energization modes

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 &#x3bc;m to 0.5 &#x3bc;m.

Glow plug and spark plug, and manufacturing method therefor

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 () comprises: a cylindrical sheath tube () closed at its front endS) and opened at its base end (K); a cylindrical metal shell () covering the side of the base end (K); a heating coil () arranged in the sheath tube () along the axis thereof and connected at its front end portion (S) to the front end (S) of the sheath tube (); and insulating powder () packed in the sheath tube (). The front end side portion (H) of the heating coil () farther than the foremost end (T) of the lead member () has a coil length not larger than 15 mm in the axial direction from the front end (S) of the sheath tube (). The sheath front end portion (C) enclosing the front end side portion (H) has an outer diameter not larger than 4.4 mm.

Glow plug, glow plug mounting structure, and glow plug manufacturing method

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.

Glow plug energization control apparatus and glow plug energization control method

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.

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

Heater and glow plug

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.

Glow plug with Ni-Fe-Co resistor

Spark plug with specific metal shell coating

A glow plug has a sheath heater, a heating coil and a control coil. The sheath heater has a sheath tube having a closed leading end. The heating coil is disposed adjacent to the leading end of a projection of the sheath tube beyond a main metal shell. The control coil is connected in series to the rear end of the heating coil and arranged to be heated by the heating coil to raise the electrical resistance to control the supply of electric power to the heating coil. The projection of the sheath tube has a substantially uniform outer diameter in the axial direction and the outer diameter is between 3.0 mm to 4.4 mm. Therefore, a temperature rising characteristic at the surface of the leading end of the sheath tube has a peak temperature TP in an initial stage of energization and saturates at a temperature not higher than the peak temperature TP.

Glow plug with small-diameter sheath tube enclosing heating and control

A sheathed heater comprises a heater disposed in a sheath tube by way of an insulation powder and is connected in series with a heat resistor and a current regulation resistor. The current regulation resistor is made from a cobalt-copper alloy which contains a copper component in the range from 1.0% to 14% by weight.

Growing community of inventors

Gifu, Japan

Chiaki Kumada