Abstract: A method of welding a noble metal tip to a spark plug center electrode comprises the steps of placing a plurality of spark plug center electrodes into a plurality of carriers so that each carrier carries one spark plug center electrode, one by one moving each carrier into a weld station, lifting the one spark plug center electrode carried in the carrier located in the weld station out of the carrier into a weld position, clamping the one spark plug center into the weld position with a single clamp located in the weld station, and welding the noble metal tip to the one spark plug center electrode, wherein the single clamp eliminates clamp-to-clamp process variations.

Abstract: Apparatus and method for welding a platinum wire to a ground electrode of a spark plug to form a contact pad of platinum material that is welded to the ground electrode. The ground electrode is attached to and extends from a metallic spark plug shell. The apparatus includes a pivotally mounted nest for receiving and supporting the spark plug shell. A movable welding electrode can be moved into engagement with a lower surface of the ground electrode. The welding electrode has a spherical end surface that engages the ground electrode. The apparatus has opposed gripping fingers that can be moved toward or away from each other. The gripping fingers each have an inclined surface. When the gripping fingers are moved toward each other their inclined surfaces engage the ground electrode to force it into tight engagement with the spherical end surface of the welding electrode. A source of welding current is connected to the wire and to the welding electrode to weld an end portion of the wire to the ground electrode.

Abstract: A laser transmitter emits a beam which scans about a scanning axis to effect a curtain of light which defines a boundary of a working space. Photosensors mounted on the outboard portion of a crane or other construction equipment generate warning signals to the construction equipment operator and other nearby personnel whenever these photosensors move into the light curtain. Additional curtain sensing equipment positioned to intercept the rotating laser beam with each cycle of rotation develops an alarm signal which activates an alarm horn and/or alarm light whenever the laser transmitter fails to provide the light curtain.

Abstract: A chain for engagement with a double sprocket has alternate pin links and center, or bushing, links. The bushing links comprise a single center bar with two laterally extending bushings tightly received therein. The pin links have side bars parallel to the center bars, and the side bars are connected together by laterally extending pins. The pins of each pin link are rotatably received in the near bushings of each of the adjacent bushing links. Rollers are received on each bushing, on each side of the center bar, to define pockets with the side bars and center bars, on each side of the center bars, to receive the teeth of a double sprocket.

Abstract: A roller chain that includes a series of alternately arranged roller links and pin links is manufactured by welding side bars to separately formed bushings and pins. Each roller link has a pair of laterally spaced side bars extending in a direction longitudinally of the chain. A pair of bushings extend transversely of the chain between the side bars and a pair of rollers are rotatably mounted on the bushings. Welds fuse each end portion of each bushing to an adjacent side bar end portion. Each pin link has a pair of laterally spaced side bars extending in a direction longitudinally of the chain, with one side bar being located on one side of an adjacent pair of roller links and the other side bar being located on the opposite side of the roller links. A pair of pins extend transversely between the side bars, through bore openings in the bushings of each roller link. Welds fuse each end portion of each pin to an adjacent side bar end portion.

Abstract: A blank, having a pair of parallel bushing forming strips that are intermediately connected by a web, is formed from stock. The blank is bent and curled in a progressive die to form a bushing link that includes a pair of cylindrical bushings integral with the web. Rollers can be slipped longitudinally over the bushing ends opposite from the web and an inside plate is welded to the bushing ends to form a roller link. Such roller links are alternately arranged with pin-links to form a roller chain. A bushing chain can be formed in essentially the same manner as the roller chain by omitting the rollers from the bushing links.

Abstract: A blank, having a pair of parallel bushing forming strips that are intermediately connected by a web, is formed from stock. The blank is bent and curled in a progressive die to form a bushing link that includes a pair of cylindrical bushings integral with the web. Rollers can be slipped longitudinally over the bushing ends opposite from the web and an inside plate is welded to the bushing ends to form a roller link. Such roller links are alternately arranged with pin-links to form a roller chain. A bushing chain can be formed in essentially the same manner as the roller chain by omitting the rollers from the bushing links.