Federal-mogul Ignition Company

Frederick James Quitmeyer

Kevin J Kowalski

Richard L Keller

Nathan A Thomson

Curtis W Verhoff

Mark McMurray

Richard Llope

A spark plug has a firing pad attached to a center electrode or to a ground electrode. The firing pad is attached via laser welding and has a sparking surface with an overall fused area and an unfused area. In one or more embodiments, the overall fused area is located in part or more inboard of a peripheral edge of the firing pad.

Spark plug having firing pad

A welding system for welding small precious metal firing tips to spark plug electrodes, such as ground and/or center electrodes. According to one embodiment, the welding system includes a firing tip storage assembly and a firing tip welding assembly, where the firing tip storage assembly uses pressurized gas introduced at the bottom of a part container to float or lift the firing tips so that the firing tip welding assembly can more easily acquire them with a vacuum-driven nozzle that also doubles as a welding electrode. The firing tip welding assembly is mounted to a robotic apparatus that can index or move the firing tip welding assembly between the firing tip storage assembly, a welding station and/or any other suitable positions.

Welding system for attaching firing tips to spark plug electrodes

A spark plug having a metal shell, an insulator, a center electrode, a ground electrode, and a multi-layer sparking component. The multi-layer sparking component is attached at a firing end of the ground electrode and includes a thin precious metal layer formed overtop a base metal layer and, according to some embodiments, overhangs the end of the ground electrode. The precious metal and base metal layers may be pre-manufactured together as a bi-metal ribbon, sheet or laminate before the multi-layer sparking component is attached to the ground electrode.

Spark plug having multi-layer sparking component attached to ground electrode

A spark plug has a firing pad attached to a center electrode or a ground electrode by way of a fused portion. In one or more embodiments, the firing pad is composed of a precious metal material. The fused portion can be formed in such a way that a material composition thereof at a sparking surface of the firing pad has a greater percentage of the precious metal material than a material of the underlying electrode to which the firing pad is attached.

A capacitive discharge welding method is used to join firing tips, such as those made from various precious metals, to spark plug electrodes. In one embodiment, charged capacitors or other energy storage devices coupled to welding electrodes quickly release stored energy so that a peak weld power and maximum interface temperature is quickly established, followed by a rapid decline in weld power and interface temperature. The resulting capacitive discharge weld joint may include solidified molten material from both the firing tip and the electrode and possess a number of other desirable qualities.

Method of capacitive discharge welding firing tip to spark plug electrode

A spark plug includes a metallic shell, an insulator, a center electrode, a ground electrode, and a thin firing pad. The thin firing pad is made from a noble metal and can be attached to the center electrode, the ground electrode, or to both. In some examples, the thin firing pad possesses certain geometric properties and relationships that can improve ignitability and durability of the thin firing pad.

Spark plug having a thin noble metal firing pad

A spark plug has a metal shell, an insulator, a center electrode, and a ground electrode. One or more firing tips can be attached to the center electrode, to the ground electrode, or to both electrodes. The metal shell and ground electrode are attached together by way of one or more laser keyhole welds at an interface of the shell and electrode. Before the laser keyhole welds, resistance welding can be executed for a temporary attachment.

Spark plug with laser keyhole weld attaching ground electrode to shell

A spark plug has a shell, an insulator, a center electrode, a ground electrode, and a firing pad. The firing pad is made of a precious metal material and is attached to the ground electrode. The firing pad has a side surface at a peripheral edge that can be flush or nearly flush with a free end surface of the ground electrode. This construction can help improve ignitability and flame kernel growth of the spark plug during a sparking event, and can provide better thermal management at the attached ground electrode and firing pad.

A method of manufacturing a spark plug that includes a metallic shell, an insulator, a center electrode, a ground electrode, and a firing pad. The method may include the steps of: applying a first laser beam to attach the firing pad to the ground electrode, and then using a second laser beam from the same laser beam welder to attach the ground electrode to the metallic shell. The laser beam welder may include a high energy density fiber laser for forming key-hole laser welds, as well as a programmable focusing optic (PFO) assembly for redirecting laser beams from one welding site to the other.

Spark plug and method of manufacturing the same

A spark ignition device has a ceramic insulator surrounded by a metal shell. The metal shell extends along a longitudinal axis to a distal end. A center electrode is received in the ceramic insulator and extends along the longitudinal axis. A ground electrode has an attachment end fixed by a weld joint to the distal end of the shell and a free end extending from the distal end to provide a spark gap. The weld joint includes a capacitive pulse discharge weld joint and a laser weld joint, which in combination inhibit material expulsion; provide a reliable, strong attachment of the ground electrode to the shell; provide an improved heat transfer path between the ground electrode and the shell, and facilitate repeatable and accurate positioning of the ground electrode to the shell. The weld joint includes a homogeneous mixture of the metal shell and the ground electrode.

Spark ignition device and ground electrode therefor and methods of construction thereof

A spark ignition device, metal shell, and methods of construction are provided. The spark ignition device has a ceramic insulator extending along a longitudinal axis and a metal shell. The metal shell extends along the longitudinal axis to a distal end. A center electrode is received in the ceramic insulator and extends along the longitudinal axis. A ground electrode has an attachment end fixed by a weld joint to the distal end of the shell and a free end extending from the distal end to provide a spark gap. The weld joint includes a resistance weld joint and a laser weld joint, which in combination inhibit material expulsion; provide a reliable, strong attachment of the ground electrode to the shell; provide an improved heat transfer path between the ground electrode and the shell, and facilitate repeatable and accurate positioning of the ground electrode to the shell.

Spark ignition device for an internal combustion engine, metal shell therefor and methods of construction thereof

A spark ignition device, ground electrode therefor, and methods of construction thereof are provided. The spark ignition device includes a generally annular ceramic insulator with a metal shell surrounding at least a portion of the ceramic insulator. A center electrode is received at least in part in the ceramic insulator and a ground electrode extends from the shell to a free end portion. A firing tip is attached adjacent the free end portion of the ground electrode to provide a spark gap between the center electrode and the firing tip. The free end portion is at least partially bounded by at least one 'as laser cut' peripheral side extending adjacent the firing tip.

Spark ignition device and ground electrode therefor and methods of  construction thereof

A spark plug includes an electrode tip assembly located at an axially-facing free end surface of an electrode body. The electrode tip assembly includes an electrode tip body and a firing tip and has a longitudinal axis that is generally perpendicular to a longitudinal axis of the electrode body. The electrode tip body may be a Ni-alloy piece and is attached to the electrode body, and the firing tip may be an Ir-alloy piece with a sparking surface that faces a spark gap. The electrode body may include a groove formed in the axially-facing free end surface that is useful to help position the electrode tip assembly for attachment. The spark gap can be formed between opposing electrode tip assemblies, and the size of the spark gap can be adjusted during assembly without the need for bending the electrode body.

Growing community of inventors

Rochester Hills, MI, United States of America

Frederick James Quitmeyer