GAS COMBUSTION APPARATUS

Abstract: A gas heating cooker to be used as a grill or an oven, wherein the blow-off air current of the blowing apparatus blows along the flames of the lower burner to get the hot current to reach far, so that the heating chamber becomes superwide enough to allow a lot of cookings, with the result that the heating operation may be effected with uniform heat distribution in the full face of the heating chamber, and superior cooking property from the uneven cooking is provided.

Description: The invention relates to a gas combustion apparatus in a heating chamber comprising a gas burner having substantially horizontal flame ports, and a blowing apparatus for blowing air along the gas flames in order to lengthen it. The invention further relates to a gas heating cooker comprising a heating chamber including such a gas combustion apparatus. From EP-A-200 626, a combustion apparatus is known in which a blowing apparatus is provided in order to lengthen the flames of a burner. By such a measure, the heat distribution of such a combustion apparatus is more even. This known combustion apparatus uses a plurality of separate gas burner units and a blowing apparatus which are individually mounted within an elongated baking oven or baking line. It is an object of the present invention to provide a gas combustion apparatus having a gas burner and a blowing apparatus for blowing air along the gas flames in order to lengthen it, which is of compact construction in order to facilitate its use in a gas heating cooker. According to the invention the gas combustion apparatus is characterized by a bulkhead for partitioning the integral member into the burner member and the blowing member. Preferable embodiments of the invention are defined in the appended dependent claims. The present invention will become clear from the following description taken in conjunction with the preferred embodiments thereof with reference to the accompanying drawings, in which: Fig. 1 is a front-face section view of a heating chamber of a gas heating cooker with a gas combustion apparatus; Fig. 2 is a perspective view of a blowing apparatus thereof; Fig. 3 is a front-face sectional view of a heating chamber of a gas heating cooker with a combustion apparatus according to the present invention; Fig. 4 is a side sectional view of Fig. 3; Fig. 5 is a perspective view of a burner unit integrated with a lower burner and a blowing apparatus of the embodiment of Fig. 3; Fig. 6 is a partial sectional view in portion A of the burner unit of Fig. 5; Fig. 7 is a system diagram showing the construction of a gas heating cooker in the embodiment of Fig. 3; Fig. 8 is a plan view of the (a) burner member, (b) bulkhead, (c) blowing member of the exploded lower burner to be used in the gas heating member of the present invention shown in Fig. 3, and the exploded burner unit of the blowing apparatus; Fig. 9 is a plan view of the (a) burner lower plate, (b) combustion plate, (c) burner upper plate of the exploded upper burner shown in Fig. 3; Fig. 10 is a graph showing the temperature distribution of the toasting net portion; and Fig. 11 is a graph showing the temperature distribution of a toasting net portion using a blowing apparatus with the duty control being effected likewise. Before the description of the present invention proceeds, it is to be noted that like parts are designated by like reference numerals throughout the accompanying drawings. In the gas heating cooker of Fig. 1, a blowing apparatus 11 is provided at the lower portion of a lower burner 8. The blowing apparatus 11 blows, through the rotation of a fan blade 15' by a fan motor 15 of a blower 14, onto a pipe 13 having numerous air exhaust ports 12 near the lower burner 8 as shown in Fig. 2. The hot air of the lower burner 8 is carried to the desired far position by the air current blowing off in the horizontal direction from the blowing apparatus 11. Also, the lower vector component is put into the blowing air current to make it possible to carry the hot air much farther. If the blowing apparatus 11 were provided at the upper portion of the lower burner 8, combustion gas would be pushed so that it may come to the central portion of the heating chamber. When the blowing apparatus 11 is provided at the lower portion of the lower burner 8, the combustion gas is pulled so that it may be brought to the central portion. The thermal distribution in a toasting net 6 portion becomes approximately uniform as shown in Fig. 10 even above or below the lower burner 8. However, when the blowing apparatus 11 is mounted on the lower portion of the lower burner 8, the temperature of a stock saucer 9 is prevented from rising. Oil falling down from food 5 to be cooked is not evaporated even if the saucer is not filled with water and the oil is not burned. Conventionally, water 10 filled in the saucer causes vapor to dampen the food 5 and to deteriorate the taste. If the stock saucer 9 is filled with water 10, the temperature rise is less, with the same effect being provided. Also, when the blowing apparatus 11 is mounted in the upper portion of the lower burner 8, the rising air current of the combustion gas is efficiently controlled, so that the hot current may be positively controlled with less blow amount. A gas heating cooker of the present invention will now be described with reference to Fig. 3 through Fig. 9. The difference in Fig. 3 and Fig. 4 with respect cooker of Fig. 1 is that the lower burner 8 is integrally combined with the blowing apparatus 11, with flame ports 75, 81 of the upper burner 7, the lower burner 8 being connected to provide a continuous combustion face. A burner unit 16 having the lower burner 8 and the blowing apparatus 11 integrally combined is shown in detail in Fig. 5, Fig. 6, Fig. 8(a), (b), (c). It is composed of a burner member 17 having numerous flame ports 81 arranged in one row or a plurality of rows, a blowing member having numerous air exhaust ports 111 arranged in one row or a plurality of rows, and a bulkhead 19 for partitioning off between the burner member 17 and the blowing member 18. A tubular portion which is formed into an approximate H-shape with the burner member 17 and the bulkhead 19, with the burner member 17, the blowing member 18, the bulkhead 19 being formed in an approximate H-shape, is turned into a burner tube 82 into which fuel and primary air flows. A gas feed portion 83 having a gas entrance from one way and a mixing tube portion with the primary air sucked with the gas is provided at both the ends of the burner tube 82, a fire transfer flame-port portion 84 is provided at the center, and a heating flame-port portion 85 is provided on both the sides. The fire transfer flame portion 84 and the heating flame-port portion 85 make the continuous combustion flame. Also, a tubular portion which has been formed into an approximate U-shape with the blowing member 18 and the bulkhead 19 is turned into an air tube 112 with air being flown therein. An air entrance 113 which is coupled to the blowing machine 14, a branch portion 114 onto both the sides and an exhaust portion 115 having an air exhaust port 111 on both the sides are provided at the center of the air tube 112. A burner member 17, a blowing member 18, a bulkhead 19 are integrally engaged by caulking or welding. The burner tube 82 and the air tube 112 are cut off by the bulkhead 19 respectively into an independent passage. A wind direction controlling member 20 (not shown in Fig. 5) which is mounted on a blowing member 18 is adapted to regulate the wind direction with respect to the flame of the lower burner 8 so that the hot current may positively reach farther. Also, the similar effect is provided even at the upper portion and the lower portion when the blowing apparatus 11 of the burner unit 16 is provided near the lower burner 8 as described. As shown in Fig. 9 (a), (b), (c), the upper burner 7 has a U-shaped opening 72 and a gas entrance 73, which become the combustion face, in the burner lower portion 71. The flame ports 75 with the combustion plate 74 composed of metal gauze, ceramic perforated plate or the like being mounted thereon are formed to cover the opening 72. The burner upper plate 76 has a burner tube 78 mutually communicated with the gas entrance 77 and the combustion plate 74. The burner lower plate 71 is integrally fixed to the burner upper plate 76, a mixing tube 79 is formed of gas entrances 73, 77, with combustion plate 74 and the burner tube 78 forming the flame port 75 to make the continuous combustion face. The front portion of the heating chamber 4 may be opened, closed by a door 21, with the rear upper portion of the heating chamber 4 becoming the exhaust port 22. Fig. 7 is a system diagram showing the construction of a gas heating cooker in one embodiment of the present invention. As described hereinabove, in a burner unit 16 integrally provided with the lower burner 8 and the blowing apparatus 11 as described hereinabove, the heat flame-port portion 85 of the lower burner 8 and the flame ports 81 of the fire transfer flame-port portion 84 forms the continuous combustion face, furthermore the flame ports 75 form the continuous combustion face as in the upper burner 7, so that a pair of right and left burners of the upper and lower burners 7, 8 are constructed so that the fire may be transferred. A firing burner 23 is confronted with the combustion face of the upper burner 7 and the lower burner 8 for ignition. A firing detector 24 to detect the existence of the ignition and an ignition plug 25 are engaged with the firing burner 23. A blowing machine 14 is connected with the air entrance 113 of the blowing apparatus 11, an electromagnetic valve adapted to open or close the gas is provided on the upper, lower and the firing burners 7, 8, 23. The gas is fed from the gas tube 27 through electromagnetic valves 261, 262, 263 corresponding to the respective burner from the main electromagnetic valve 26. An operation portion 28 is adapted to select in advance and set the heating operation by the upper and lower burners 7, 8. The gas is inputted from the operation portion 28, the firing detector 24 by the controlling portion 29. It is outputted through the respective electromagnetic valves 26, 261, 262 and 263. A controlling portion 29 controls the gas heating cooker. Reference character 30 refers to a power supply. When the size, shape, amount and so on of the food to be cooked 5 are varied, and further the applying operation is effected in the wide heating chamber 4, control of the blow amount of the blowing apparatus 11 and much more effect are provided so that uniform heating for better thermal distribution is provided. The gas burner is operated as follows. (1) Effect the duty control by the on/off of the blowing machine 14 with the heating of the central portion being increased during the blowing time, and the strong heating portion is moved from right to left, so that uniform heating is provided. In addition, methods of obtaining the similar effect to that of (1) are as follows. (2) Control for effecting the blowing operation from one way of the blowing apparatus 11 so as to effect the alternate operation. (3) Control for pulsating the blow amount from maximum to minimum. (4) Control for adjusting the wind-direction angle of the wind direction control member 20. Better cooking results are provided even in any control method of the above description. Fig. 10 and 11 show the temperature distribution of the toasting net 6 portion by the duty control of the above-described (1). 15 seconds on condition of the blowing machine 14, and 5 seconds off condition are alternately repeated. One-dot chain line (A) of the drawing shows the temperature distribution of the off condition in the blow machine, with two-dot chain line (B) being the on condition in the blowing machine 14. They are averaged, showing the temperature distribution of the solid line (C) as the result, so that the uniform thermal distribution is provided. A heat shielding plate 31 which is shown in Fig. 1, Fig. 3, Fig. 7 is detachably mounted under the toasting net 6 of the heating chamber 4. It is used in the oven for cooking, while it is removed for grill cooking, so that the cooking versatility is widened. In the construction, the upper burner 7 and the lower burner 8 are ignited. Air flow which has horizontal or lower vector components is jetted along the flame directed from the air jetting ports 111 of the blowing apparatus 11 into the horizontal direction of the lower burner 8, so that hot current reaches so far as the lower central portion of the toasting net 6 to heat the entire face with uniform thermal distribution. At this time, simultaneous heating is effected from both the upper and lower surfaces forces of the food 5 by the radiation heat from the combustion of the upper burner 7, so that fast and even cooking property is ensured even in a superwide heating chamber 4. The wind direction is controlled by the wind direction control member 20 near the blowing apparatus 11, the blow amount of the blowing apparatus 11 is controlled to sequentially move the strong heating portion, thus resulting in uniformed thermal distribution in the superwidened heating chamber 4, which improves much better cooking effect. As a firing burner 23 provided with a firing detector 24 is confronted with the upper burner 7 and the lower burner 8 with a pair of right and left burners being formed of the continuous combustion face, the fire may be positively moved, so that the heating operation may be effected by a burner selected by the operation portion 28, with no risk of raw gas to leak out.

Claims: A gas combustion apparatus in a heating chamber (4) comprising a gas burner (8) having in use subtstantially horizontal flame ports (81), and a blowing apparatus (11) for blowing air along the gas flames in order to lengthen it, whereby the gas burner (8) and the blowing apparatus (11) are formed as an integral unit (16) of a burner member (17) having numerous combustion flame ports (81) arranged in one row or in a plurality of rows, a blowing member (18) having numerous air jetting ports (111) arranged in one row or in a plurality of rows characterized by a bulkhead (19) for partitioning the integral unit (16) into the burner member (17) and the blowing member (18). Apparatus according to claim 1, characterized in that a tubular portion formed by the burner member (17) and the bulkhead (19) is turned into a burner tube (82) through which premixed gas between fuel and primary air flows, and that a tubular portion formed by the bulkhead (19) and blowing member (18) is turned into an air tube (112). Apparatus in accordance with claim 2, characterized in that two burner tubes (82) are provided oppositely to each other at a distance and each comprising a gas supply portion (83) and a heating flame-port portion (85) connected with each other, both burner tubes being connected with each other by a fire transfer flame-port portion (84); and the air tube (112) of the blowing member (18) has a branch portion (114) having an air entrance (113) connected with a blowing machine (14) and air jetting portions (115) provided opposite on both sides. Apparatus in accordance with any of claims 1 to 3, characterized by a plurality of air jetting ports (111), a wind direction controlling member (20) near the blowing member (18) for regulating the wind direction. Apparatus in accordance with any of claims 1 to 4, wherein the air jetting ports (111) of the blowing member (18) are provided under the burner member (17). Apparatus in accordance with any of claims 1 to 4, wherein the air jetting ports (111) of the blowing member (18) are disposed above the burner member (17). Apparatus in accordance with claim 5, wherein the air blow-off direction of the blowing member (18) has a downward vector component. A gas heating cooker comprising a heating chamber (4), a gas combustion apparatus according to any preceding claim as a lower gas burner (8), a toasting net (6) having the food (5) to be cooked at a vertically intermediate portion of the heating chamber (4) so as to effect the toasting operation, an upper gas burner (7) provided above the toasting net (6), and the lower gas burner (8) being provided below the toasting net (6). Gas heating cooker according to claim 8, characterized by a firing burner (23) which is confronted with the combustion face of the upper gas burner (7) and the lower gas burner (8) to ignite, a firing detector (24) which is confronted with the firing burner (23) to detect the existence of the ignition, electromagnetic gas valves (261, 262, 263) for turning on/off the gas to be fed to the upper gas burner (7), the lower gas burner (8) and the firing burner (23), an operation board (28) for controlling the heating by the upper gas burner (7) and the lower gas burner (8), a control portion (29) controlled by the operating board (28), the firing detector (24) and controlling electromagnetic gas valves (261, 262, 263) and the blowing machine (14). Gas heating cooker in accordance with claim 9, wherein the blowing apparatus is switched on and off with a certain duty cycle in accordance with the output of the control portion (29). Gas heating cooker in accordance with any of claims 8 to 10, characterized by a detachable heat shielding plate (31) which can be selectively placed between the toasting net (6) and the lower gas burner (8) for selecting between the functions of an oven and a grill.

Inventors: KAGOMOTO, YOSHITERU, SHIMADA, YOSHIHARU, TAKATA, MANABU, TANAKA, JUNZO
Applicants: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
Application year: 1988
Main classification: F24C3
IPC codes: F24C15, F24C3