Abstract: Mechanical pressure exerted by a spring on the diaphragm of a pressure regulator is adjusted by an inclined cam surface on a linearly movable slide member.Flow of gases to a gas-fired torch is controlled by a valve which is operatively connected to an inclined cam surface on a linearly movable slide member.A gas-fired torch assembly has a housing, a tip base extending laterally of the housing and connected thereto for swivelling movement by a connector with male and female portions. A spring retainer clip on the exterior of the female portion extends through slots in the female portion and into a circumferential groove in the male portion. Upon separation of the connector elements, a safety cutoff valve closes the gas outlet of the housing.A burner tip base has a passage provided with a dust plug which prevents contaminants from entering the burner tip when it is detached from a torch assembly. In use, gas pressure moves the dust plug to a passage-opening position.