A system for testing an insulative material for a spark plug comprises a test spark plug having at least a center electrode and an insulator comprised of an insulative material surrounding at least a portion of the center electrode, wherein the insulator has an end that is closed, whereby the closed end of the insulator encloses an end of the center electrode. The system further includes a test engine that simulates engine conditions, wherein a conventional spark plug is installed in a first ignition port of the test engine and the test spark plug is installed in a second ignition portion of the test engine and a control system for controlling ignition signals to the test spark plug and the conventional spark plug.

A method of manufacturing a spark plug including a cylindrical tubular metallic shell having a screw portion on an outer surface thereof and a ground electrode attached to an end surface at one end of the metallic shell in the direction of the center axis thereof comprises a measurement step of measuring a surface of the screw portion which passes through a measurement region located at a predetermined position in the direction of the center axis, while rotating the metallic shell about the center axis thereof; an attachment position calculation step of calculating, on the basis of information obtained in the measurement step, an attachment position at which the ground electrode is attached to the end surface; and a joining step of joining the ground electrode to the end surface at the attachment position, wherein the measurement step includes a step of measuring a displacement of the surface of the screw portion by using a non-contact-type displacement sensor.

A method of manufacturing a spark plug including a cylindrical tubular metallic shell having a screw portion on an outer surface thereof and a ground electrode attached to an end surface at one end of the metallic shell in the direction of the center axis thereof comprises a measurement step of measuring a surface of the screw portion which passes through a measurement region located at a predetermined position in the direction of the center axis, while rotating the metallic shell about the center axis thereof; an attachment position calculation step of calculating, on the basis of information obtained in the measurement step, an attachment position at which the ground electrode is attached to the end surface; and a joining step of joining the ground electrode to the end surface at the attachment position, wherein the measurement step includes a step of measuring a displacement of the surface of the screw portion by using a non-contact-type displacement sensor.

The present application provides a spark plug testing tool for a spark plug assembly of a gas turbine engine combustor. The spark plug testing tool may include a dielectric tube attached to the spark plug assembly and a first support bracket to support the spark plug assembly and the dielectric tube therein such that the spark plug assembly remains electrically connected to the gas turbine engine combustor during testing.

The present application provides a spark plug testing tool for a spark plug assembly of a gas turbine engine combustor. The spark plug testing tool may include a dielectric tube attached to the spark plug assembly and a first support bracket to support the spark plug assembly and the dielectric tube therein such that the spark plug assembly remains electrically connected to the gas turbine engine combustor during testing.

In the spark plug heat rating measurement method and system based on spark discharge current active heating, the spark plug is installed in a constant-temperature water jacket cooling chamber with a specific torque. A constant spark discharge current control module is connected to the high-voltage terminal of the spark plug, to provide real-time controlled discharge current to heat up the high-voltage central electrode of the spark plug. During the spark discharge process, the temperature change of the high-voltage central electrode and the surrounding ceramic insulator are measured by a temperature detection module and used to determine the heat rating of the spark plug. By real time adjusting the discharge current level of the spark plug, or providing a same amount of spark energy to the spark gap, the heat ratings of spark plugs with different ceramic insulation structures can be evaluated through the temperature changes during discharge or after discharge.

A spark plug heat up method via transient control of the spark discharge current. The high temperature plasma channel is used to heat up the central electrode, and the temperature and energy of the plasma channel are realized via transient control of the discharge current. The heating up process takes place before firing the engine, using discharge current to actively heat up the spark plug from inside. By monitoring the discharge current amplitude and discharge duration, the temperature change of the central electrode and the ceramic insulator can be carefully measured and controlled within a proper window. This method can be used to measure the heating range of the spark plug, and to prevent or remove the carbon deposit on the central electrode and the ceramic insulator generated under various engine operation conditions, such as engine cold start, full load operation, and heavy EGR condition, as well as realize self-cleaning.

A spark plug heat up method via transient control of the spark discharge current. The high temperature plasma channel is used to heat up the central electrode, and the temperature and energy of the plasma channel are realized via transient control of the discharge current. The heating up process takes place before firing the engine, using discharge current to actively heat up the spark plug from inside. By monitoring the discharge current amplitude and discharge duration, the temperature change of the central electrode and the ceramic insulator can be carefully measured and controlled within a proper window. This method can be used to measure the heating range of the spark plug, and to prevent or remove the carbon deposit on the central electrode and the ceramic insulator generated under various engine operation conditions, such as engine cold start, full load operation, and heavy EGR condition, as well as realize self-cleaning.

The present disclosure relates to voltage sensing mechanisms. One example embodiment includes a voltage-measurement device. The voltage-measurement device includes a housing. The voltage-measurement device also includes an extendible gripper configured to be removably attached to a wire under test. Additionally, the voltage-measurement device includes at least one power supply. Further, the voltage-measurement device includes a power management chip electrically coupled to the at least one power supply and configured to manage a range of input voltages from the at least one power supply. The power management chip comprises a synchronous boost voltage regulator. Additionally, the voltage-management device has a microprocessor electrically coupled to the power management chip and the extendible gripper. The microprocessor is configured to receive electrical power from the power management chip. The microprocessor is also configured to receive an electrical signal from the extendible gripper indicative of a voltage associated with the wire under test.

The present disclosure relates to voltage sensing mechanisms. One example embodiment includes a voltage-measurement device. The voltage-measurement device includes a housing. The voltage-measurement device also includes an extendible gripper configured to be removably attached to a wire under test. Additionally, the voltage-measurement device includes at least one power supply. Further, the voltage-measurement device includes a power management chip electrically coupled to the at least one power supply and configured to manage a range of input voltages from the at least one power supply. The power management chip comprises a synchronous boost voltage regulator. Additionally, the voltage-management device has a microprocessor electrically coupled to the power management chip and the extendible gripper. The microprocessor is configured to receive electrical power from the power management chip. The microprocessor is also configured to receive an electrical signal from the extendible gripper indicative of a voltage associated with the wire under test.