Patent Application
20120301836
1. Field of the Invention
The present invention relates to a plate type burner including a box-shaped burner main body with an upper surface formed as an open surface and burning plates mounted on the open surface of the burner main body for burning a mixture gas by jetting the mixture gas from the inside of the burner main body to the outside thereof through a multiplicity of burner ports formed in the burning plates.
2. Description of the Related Art
Conventionally, as this type of plate type burner, the following one is known (see, for example, Japanese Patent Application Laid-Open Publication No. 2004-333099). That is, a flange portion enclosing the open surface is formed on the upper surface of the burner main body; the outer edge of each of the burning plates is placed on the flange portion with an annular sheet of packing put between them; and the sealing property between the burner main body and each of the burning plates is secured by pressing the outer edge of each of the burning plates downward with a pressing plate to compress the packing.
Moreover, a plurality of burning plates is sometimes mounted by being arranged on the open surface of the burner main body in such a plate type burner. In this case, in order to prevent gas leakage from the butting parts of the burning plates, it becomes necessary to press the burning plates situated on both the outer sides in the arrangement direction of the plurality of burning plates to the inner side in the arrangement direction with spring members. Consequently, the number of parts increases and an increase in cost is brought about.
In view of the above-mentioned problems, it is an advantage of the present invention to provide a low cost plate type burner capable of preventing any gas leakage from butting (butt joint) parts of burning plates without using any spring members.
According to an aspect of the present invention, there is provided a plate type burner, comprising: a burner main body shaped in a box with an upper surface thereof being formed as an open surface; and a plurality of burning plates mounted side by side in the open surface so that a mixture gas is jetted for combustion from inside the burner main body through a multiplicity of burner ports formed in each of the burning plates. The burner main body has formed on the upper surface thereof a flange portion in a manner to enclose the open surface. Each of the burning plates is placed on the flange portion at an outer edge thereof with an annular packing being interposed therebetween such that, by pressing downward the outer edge of each of the burning plates by a pressing plate to compress the packing, sealing property is secured between the burner main body and each of the burning plates. The flange portion is formed in a stepped shape with an inner part on a side of the open surface being lower than an outer part. A vertical stepped part between the inner part and the outer part is formed at a position where a gap narrower than a thickness of the packing in a free state thereof is produced between an end face of the outer edge of each of the burning plates and the stepped part. The packing is formed in a size large enough to project from the inner part of the flange portion to the outer part thereof beyond the stepped part.
According to the aspect of the present invention, when the outer edge of each of the burning plates is pressed downward with the pressing plate, the packing is compressed between the inner part of the flange portion and the under surface of each of the burning plates. Furthermore, also between the end face of the outer edge of each of the burning plates and the stepped part of the flange portion, the packing is compressed, and consequently the sealing property between the burner main body and each of the burning plates becomes good. Moreover, the burning plates situated on both the outer sides in the arrangement direction of the plurality of burning plates are pressed to the inner sides in the arrangement direction by the reaction forces of the compression of the packing between the outer edges on the outer sides in the arrangement direction of the burning plates and the stepped portion. Consequently, the gas leakage from the butting parts of the burning plates can be prevented without using any spring members, and the number of parts can be decreased to enable cost reduction.
Now, the open surface of the burner main body and each of the burning plates are generally formed in a square in plan view. In this case, if the corner parts formed by the end faces of the outer edges on the outer sides in the arrangement direction of the burning plates situated on both the outer sides in the arrangement direction of the plurality of burning plates and the end faces of the outer edges parallel to the arrangement direction are angular, excess thickness parts of the packing produced at the time of drawing the packing between the corner parts of the burning plates and the corner parts of the stepped part situated on the outer side of the corner parts of the burning plates by pressing the burning plates downward gathers together on the under surfaces of the corner parts of the burning plates to wrinkle, and the sealing property is deteriorated.
Accordingly, the corner parts of the burning plates situated on both the outer sides in the arrangement direction of the plurality of burning plates is preferably formed in chamfered shapes. The gap between the corner parts of the burning plates and the corner parts of the stepped part situated on the outer side of the corner parts of the burning plates consequently becomes wide, and the excess thickness parts of the packing can be received in the gap. Consequently, the excess thickness parts of the packing do not gather together and wrinkle on the under surface of the corner parts of the burning plates, and good sealing property between the burner main body and the burning plates can be secured.
Moreover, in the present invention, it is preferable that a chamfered portion is formed on an upper edge of the stepped part. When the packing is drawn between the stepped part and the end face of the outer edge of each of the burning plates by pressing each of the burning plates downward, it can consequently be prevented that the packing is caught by the corner on the upper edge of the stepped part and is damaged.
Moreover, in the present invention, it is preferable that an adhesive is coated on an under surface of the packing, and the packing is adhered to at least one of the inner part and the outer part of the flange portion. When the burning plates are set on the packing, the packing can thereby be prevented from being displaced, and the working property of the assembling of the burner is improved.
Advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention, in which drawings:
Embodiments of the present invention will be described with reference to the accompanying drawings.
With reference to
A flange portion 3 enclosing the open surface 1a is formed on the upper surface of the burner main body 1. Then, the outer edge of each of the burning plates 2 is placed on the flange portion 3 with a square annular sheet of packing 4, made of “Kaowool” (trade name of ceramic fibers produced by ISOLITE INSULATING PRODUCTS CO., LTD. of Japan) or the like, put between the outer edge and the flange portion 3, and the packing 4 is compressed by pressing the outer edge of each of the burning plates 2 with a square annular pressing plate 5 downward to secure the sealing property between the burner main body 1 and each of the burning plates 2. Incidentally, although a sheet of packing punched into a square annular shape can be used as the packing 4, two sheets of packing punched in a letter L may be combined with each other to constitute the square annular sheet of packing 4. Moreover, another sheet of packing 6 is provided between the butting parts of the burning plates 2.
The flange portion 3 is formed in a stepped shape in which the inner part 3a on the side of the open surface 1a is lowered than the outer part 3b, and a stepped part 3c shaped in the vertical direction is formed between the inner part 3a and the outer part 3b. Moreover, a plurality of screw holes 3d is formed in the outer part 3b.
The packing 4 is formed in a size to cover the screw holes 3d in the state of extending from the inner part 3a of the flange portion 3 and exceeding the stepped part 3c thereof to project to the outer part 3b thereof. Moreover, through-holes 4a are formed at the parts of the packing 4 agreeing with the positions of the screw holes 3d.
Through-holes are formed also at the positions in the pressing plate 5 agreeing with those of the screw holes 3d, and the pressing plate 5 is fastened to the flange portion 3 with screws 5a screwed into the screw holes 3d through the through-holes formed in the pressing plate 5 and the through-holes 4a of the packing 4. Moreover, a clamping plane 2b lower than the upper surface of the burner port forming region of each of the burning plates 2 is formed by cutting work on the upper surface of the outer edge of each of the burning plates 2. Then, an engaging portion 5b rising upward to engage with the clamping plane 2b is formed in the inner edge part of the pressing plate 5, and the outer edge of each of the burning plates 2 is thereby pressed downward by the engaging portion 5b at the time of fastening the pressing plate 5 to the flange portion 3. Incidentally, the above configuration of forming the clamping planes 2b to be lower than the burner port forming regions enables the engaging portion 5b of the pressing plate 5 engaging the clamping plane 2b to be distant from the flames produced on the burner port forming regions. Thereby, the thermal deformation of the pressing plate 5 is suppressed to enable the pressing plate 5 to stably press the burning plates 2.
The stepped part 3c of the flange portion 3 is here formed at positions where a gap “a” between the end face of the outer edge of each of the burning plates 2 and the stepped part 3c is formed which gap “a” is narrower than the thickness t of the packing 4 in the free state thereof. For example, if the thickness t of the packing 4 in the free state thereof is 2 mm, the position of the stepped part 3c is set in order that the gap “a” between the end face of the outer edge of each of the burning plates 2 and the stepped part 3c may be 1 mm.
Furthermore, a chamfered portion 3e in an inclined surface is formed at the upper edge of the stepped part 3c. Moreover, as shown in
At the time of assembly of the plate type burner, first, as shown in
At this time, the packing 4 is compressed between the inner part 3a of the flange portion 3 and the under surface of the outer edge of each of the burning plates 2, and the packing 4 is compressed also in the gap “a” between the end face of the outer edge of each of the burning plate 2 and the stepped part 3c of the flange portion 3 because the gap “a” is narrower than the thickness t of the packing 4 in the free state thereof. The sealing property between the burner main body 1 and each of the burning plates 2 thus becomes good. Moreover, each of the burning plates 2 is pressed to the inner part in the arrangement direction by the reaction force of the compression of the packing 4 between the end face of the outer edge on the outer side in the arrangement direction and the stepped part 3c. Consequently, without using any spring members pressing each of the burning plates 2 onto the inner side in the arrangement direction, the packing 6 provided between the butting parts of the burning plates 2 is sufficiently compressed, and gas leakage from the butting parts can be prevented. Consequently, no spring members become necessary, and the number of the parts can be reduced to achieve cost reduction.
Moreover, because the chamfered portion 3e is formed at the upper edge of the stepped part 3c, it can be prevented that the packing 4 is caught by the corner of the upper edge of the stepped part 3c to be damaged at the time of drawing the packing 4 into the gap “a” between the stepped part 3c and the end face of the outer edge of each of the burning plates 2 by pressing each of the burning plates 2 downward.
Furthermore, because the corner parts 2c on the outer side in the arrangement direction of each of the burning plates 2 are formed in chamfered shapes, the gaps between the corner parts 2c and the corner parts 3f of the stepped part 3c which corner parts 3f are situated on the outer side of the corner parts 2c become wide. Then, the excess thickness parts of the packing 4 produced along with the drawing of the packing 4 into the corner parts 3f of the stepped part 3c are received in the gaps. Consequently, the excess thickness parts of the packing 4 does not gather together to wrinkle on the under surface of the corner parts 2c of the burning plates 2. Thus, the sealing property between the burner main body 1 and the burning plates 2 can be secured to be good.
Next, a second embodiment shown in
By this configuration, the positional displacement of the packing 4 at the time of setting each of the burning plates 2 on the packing 4 can be prevented, and the workability of the assembling of the parts is improved. Incidentally, the packing 4 may previously be adhered to either the inner part 3a or the outer part 3b of the flange portion 3.
Although the embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is no limited to those embodiments. For example, in the embodiments, the number of the burning plates 2 is two, and the burning plates situated on both the outer sides in the arrangement direction correspond to these two burning plates 2. Consequently, the corner parts 2c of each of the burning plates 2 on the outer sides in the arrangement direction are formed in the chamfered shapes. But, if three or more burning plates are mounted by being arranged on the open surface 1a of the burner main body 1, the corner parts of only the two burning plates situated on both the outer sides in the arrangement direction are formed in the chamfered shapes.
Moreover, although the upper surface of the burner main body 1 is formed as the open surface 1a in the embodiments, the vertical direction does not regulate the directions of the burner at the time of its use, and the present invention includes also the burners used in a downward posture turning the burning plates 2 downward and a lateral posture turning the burning plates 2 into a lateral direction in addition to the burner used in the upward posture turning the burning plates 2 upward.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
