GB1457171A - Piezoelectric burner igniters and systems - Google Patents

Abstract

1457171 Spark generator; burners A C MERCER and O R HILLIARD 22 Jan 1974 [22 Jan 1973] 02986/74 Headings F4F and F4T A spark generator comprises a cylinder 29, Fig. 1, with an inlet at one end, a piezoelectric crystal 35 secured to the opposite end, a piston 51 having a hammer 50 secured thereto and being slidable within the cylinder and arranged to strike the crystal in response to fluid pressure applied at the inlet and a return spring 52 acting on the piston to return it to the inlet end of the cylinder. Crystal 35 is keyed to the cylinder 29 at 36, the assembled igniter is located on a propane-type torch 10 by an adaptor 26, and piston 51 is held in the armed position by a spring-urged detent 71. In operation, a valve 12 is opened and gas from container 11 flows through an orifice 18, a Venturi-section 17, and metal fins 24, to the discharge end of the torch. When the gas pressure at inlet 57 reaches a predetermined value detent 71 is released and hammer 50 strikes crystal 35 to thus ignite the torch. In a modification, pilot burner 16 and single-shot igniter 25, Fig. 4, are incorporated in a heating device having a main burner 76, and a valve assembly 78 connected to a gas container 80. In operation, liquid fuel is supplied to burner 76 through a conduit 85 and this fuel is also supplied to a chamber 106 in valve 78. Piston 91 is moved downwardly to close passage 97 and open outlet 100, so that gas which has accumulated in a chamber 107 passes through a passage 113 and outlet 100 to pilot burner 16 and igniter 25, so that the pilot burner and subsequently the main burner 76 are ignited. In a further modification, a multiple-shot igniter (134), Fig. 5 (not shown), is provided.