A gas burner for food cooking apparatus

Abstract: The gas burner for open-fire food cooking apparatus comprises a nozzle (1) from which combustible gas issues, a mixer tube (2) composed of a converging portion (20), a gulley (21) and a diverging portion (22), in which the gas issuing from the nozzle (1) is mixed with a portion of combustion air, and also comprises a gas ring provided with flame holes, wherein an axis of the mixer tube (2) is inclined with respect to a vertical.

Description: Specifically, though not exclusively, the invention is usefully applied to gas burners of a type comprising a nozzle from which combustible gas issues; the gas is then mixed with a portion of combustion air in a mixer tube or Venturi tube, above which a burner ring is provided, horizontally arranged in one or more rings. In the commonest prior art applications, the mixer tube, also known as a Venturi tube, is located vertically above the nozzle from which the gas issues. This tube, however, is inevitably prone to being directly hit by particles of dirt which can seriously compromise its functionality and efficiency. An attempt to solve this problem has been made by designing dogleg-shaped burners in which the mixer tube and therefore the nozzle are arranged upstream of a 90° elbow in the vertical tract of the tube taking the mixture of air and gas to the gas ring. This solution, however, has the drawback that on removal of the gas ring the nozzle is not visible and cannot be inspected simply and safely from above. A further drawback is that residues of dirt might collect in the elbow, a difficult place to reach and therefore to clean. US-A-5 401 164 discloses a gas burner for a cooking apparatus which comprises : - a nozzle from which combustible gas issues; - a mixer tube, inclined with respect to a vertical axis, and composed of a converging portion, a gulley, and a diverging portion, in which the gas issuing from the nozzle is mixed with combustion air;- a gas ring provided with flame holes. GB-A-1 243 814 disclose a gas burner for a cooking apparatus which differs from US-A-5 401 164 since the axis of the mixer tube is horizontal. JP-A- 61086507 discloses a gas burner which comprises : - a nozzle; a gas ring and a dogleg-shaped mixer tube. The main aim of the present invention is to obviate the limitations and drawbacks inherent in the prior art. An advantage of the invention is that the nozzle is very easily inspected and cleaned from the outside when the gas ring is removed. These aims and advantages and others besides are all attained by the invention as it is characterised in the appended claims. Further characteristics and advantages of the present invention will better emerge from the detailed description that follows of a preferred but non-exclusive embodiment of the invention, illustrated purely by way of nonlimiting example in the accompanying figure of the drawing, in which: figure 1 is a schematic section made according to a plane containing the axis of the mixer tube. With reference to figure 1, 1 denotes a nozzle from which combustible gas issues, being part of a gas burner for food cooking apparatus, especially for cooking foodstuffs on an open flame. The burner, of the atmospheric type, apart from the nozzle 1 comprises a burner body 31 and an injector or mixer tube, or Venturi tube 2, made up of a converging portion 20, a gulley 21 and a diverging portion 22, in which the gas exiting from the nozzle 1 is mixed with a portion of combustion air A gas ring 3 with flame holes, which are arranged in one or more horizontal rings, is provided at the top of said burner body 31. Said mixer tube 2, which issues a gas-air mixture to said burner body 31, has a straight axis and is coupled to the burner body 31 in a seating 4 which is located at the bottom of said burner body 31. The special quality of the burner is that the mixer tube 2 has an inclined axis with respect to the vertical of an angle α. The entity of the inclination is such that the vertical projection of none of the internal sections of the mixer tube 2 comprised between the outlet mouth of the diverging portion 22 and the gulley 21 intercepts the nozzle 1. The mixer tube 2 has a straight axis and is coupled coaxially in a seating 4 which is coaxial to the nozzle 1. This means that once the gas ring 3 is removed the nozzle 1 is perfectly visible from outside and can be inspected. At the same time the nozzle 1 is protected from the fall of dirt coming from the exit section of the diverging portion 22 of the mixer tube 2 since, thanks to the inclination of the mixer tube 2, the nozzle 1 cannot be directly hit.

Claims: A gas burner for open-fire food cooking apparatus comprising burner body (31), a nozzle (1) for issuing combustible gas, a mixer tube (2) being composed of a converging portion (20), a gulley (21) and a diverging portion (22), in which the gas issuing from the nozzle (1) is mixed with a portion of combustion air, said mixer tube (2) issuing a gas-air mixture to said burner body (31), a gas ring (3) with flame holes being provided at the top of said burner body, said mixer tube (2) having a straight axis and being coupled to said burner body (31) in a seating (4) which is located at the bottom of said burner body (31), characterized in that said seating (4) is coaxial with the axis of the mixer tube (2). The gas burner of claim 1, characterised in that the axis of the mixer tube (2) is inclined such that a vertical projection of no section comprised between an exit mouth of the diverging portion (22) and the gulley (21) intercepts the nozzle (1).

Inventors: SILVESTRI NELLO, VEZZANI WILLIAM, SILVESTRI, NELLO, VEZZANI, WILLIAM
Applicants: GRANDI ANGELO CUCINE SPA, ANGELO PO GRANDI CUCINE S.P.A.
Application year: 2001
Main classification: F23D14
IPC codes: F23D14