JP6521437B2 - Firing furnace - Google Patents

Description

  BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a firing furnace, and more particularly, to an improvement of a firing furnace provided with a furnace door that is openably and closably attached to a furnace body.

  The baking furnace is a furnace for baking a molded body such as clay at a high temperature, and is used for the production of pottery goods, industrial goods and the like. For example, the firing furnace includes a furnace body having a furnace chamber surrounded by a heat insulating material, and a furnace door attached to the furnace body openably and closably and closing an opening of the furnace chamber. A furnace door is comprised by the door main body, the heat insulating material which opposes a furnace chamber, and the holding member holding a heat insulating material. In the case of a small desktop furnace, the furnace door is disposed on the front of the furnace body, and hinges are provided on either the left or right of the door body.

  The heat insulating material of the furnace door is in contact with the heat insulating material of the furnace main body with the peripheral portion of the back surface facing the furnace chamber when the furnace door is closed. If a gap is formed between the heat insulating material of the furnace door and the heat insulating material of the furnace main body due to the effects of shrinkage, distortion, damage, etc. of the heat insulating material, the heat in the furnace chamber leaks out of the furnace. Therefore, a firing furnace has been proposed that is provided with biasing means for biasing the heat insulating material of the furnace door toward the furnace chamber, and pressing the heat insulating material of the furnace door against the heat insulating material of the furnace main body suppresses the leakage of heat. (E.g., Patent Documents 1 and 2).

  In the door device of the ceramic furnace described in Patent Document 1, the screw member 212 around which the compression spring 24 is wound penetrates the lower hole of the holding plate 23 and is screwed to the outer peripheral flange 211 of the inner frame 21. The inner frame 21 surrounds the three layers of heat insulating materials 251 to 253. The heat insulators 251 to 253 are biased to the back side via the holding plate 23 by the action of the compression spring 24.

  In the baking furnace described in Patent Document 2, the heat insulating material wall 23 is biased toward the baking chamber 7 by processing the metal inner wall 21A of the open / close door 29 into a curved shape. The metal inner wall 21A contacts the central portion of the front surface of the heat insulating material wall 23, and biases the heat insulating material wall 23 to the baking chamber 7 side.

JP 2001-316166 A JP, 2006-46778, A

  In the door device described in Patent Document 1, since the compression spring 24 is a separate member from the holding plate 23 and the inner frame 21, the number of parts is increased and the number of mounting steps is increased, and the manufacture of the furnace door is complicated. There is a concern Further, in the baking furnace described in Patent Document 2, since the metal inner wall 21A is brought into contact with the central portion of the heat insulating material wall 23 having a high temperature, the metal inner wall 21A is covered on the cover 11A covering the outside of the metal inner wall 21A. The heat may be transferred through it, which may reduce the thermal efficiency. Further, in the baking furnace described in Patent Document 2, since the central portion of the front surface is pressed, the heat insulating material wall 23 may be deformed or the heat insulating material wall 23 may be damaged.

  This invention is made in view of the said situation, and it aims at providing the baking furnace which improved the sealing degree of the furnace chamber, suppressing that a number of parts increase. Moreover, it aims at providing the baking furnace which can improve the airtightness of a furnace chamber, suppressing that the heat insulating material of a furnace door deform | transforms or damage.

  A firing furnace according to the present invention comprises a furnace body having a furnace chamber surrounded by a first heat insulating material, and a furnace door attached to the furnace body openably and closably and closing an opening of the furnace chamber. The furnace door has a door body, a second heat insulating material facing the furnace chamber, and a holding member for holding the second heat insulating material. With the second heat insulating material, the peripheral edge portion of the back surface facing the furnace chamber contacts the first heat insulating material when the furnace door is closed. The holding member has a leaf spring that contacts the peripheral edge of the front surface of the second heat insulating material and biases the second heat insulating material toward the furnace chamber.

  The second heat insulating material of the furnace door closes the opening of the furnace chamber when the furnace door is closed, and contacts the first heat insulating material of the furnace main body at the peripheral portion of the opening of the furnace chamber. The second heat insulating material is urged toward the furnace chamber by the plate spring of the holding member. By the action of the leaf spring, the second heat insulating material is pressed against the first heat insulating material, and the degree of sealing of the furnace chamber can be increased. In addition, since the holding member has a plate spring, the number of parts can be reduced and the manufacture can be simplified as compared with the case where the urging means for urging the second heat insulating material is a separate member from the holding member. Can.

  Further, in the baking furnace, since the leaf spring contacts the peripheral portion of the second heat insulating material, the biasing member may not be in contact with the central portion where the temperature is high, and the heat from the second heat insulating material to the door main body Leak is small. Moreover, the peripheral part of the back of the 2nd heat insulating material of a furnace door contacts the 1st heat insulating material of a furnace main body. On the other hand, the leaf spring of the holding member contacts the peripheral edge of the front surface of the second heat insulating material. Therefore, in the baking furnace, the peripheral portion in contact with the first heat insulating material is pressed, and the second heat insulating material is deformed as compared with the case where the biasing member is in contact with the central portion of the second heat insulating material. Alternatively, damage can be suppressed.

  In the firing furnace according to the present invention, the degree of sealing of the furnace chamber can be improved while suppressing an increase in the number of parts. Moreover, in the baking furnace according to the present invention, the degree of sealing of the furnace chamber can be improved while suppressing the deformation or breakage of the heat insulating material of the furnace door.

FIG. 1 is an external view of a firing furnace 1 according to an embodiment. FIG. 2: is sectional drawing which shows the cut surface at the time of cut | disconnecting the kiln 1 by an AA cutting line. FIG. 3 is an external view showing the back of the furnace door 2. FIG. 4: is sectional drawing which shows the cut surface at the time of cut | disconnecting the furnace door 2 by BB cutting line. FIG. 5 is an exploded perspective view of the furnace door 2. FIG. 6 is an external view of the holding plate 22. As shown in FIG. FIG. 7 is a cross-sectional view showing a cross section of the holding plate 22 taken along the line C-C.

<Firing furnace 1>
FIG. 1 is an external view showing a configuration example of a firing furnace 1 according to an embodiment of the present invention, and a front view of the horizontal lid type firing furnace 1 is shown. FIG. 2: is sectional drawing which showed the cut surface at the time of cut | disconnecting the kiln 1 of FIG. 1 by AA cutting line. FIG. 2 shows the case where the cut surface is viewed from the direction of the arrow.

  The baking furnace 1 is a small table-top electric furnace, and is a furnace main body 10 having a furnace chamber 11 surrounded by a heat insulating material 12 and a furnace which is attached to the furnace main body 10 openably and closably. It is comprised by the door 2.

  The heat insulating material 12 is a first heat insulating material disposed in the furnace body 10. For example, as the heat insulating material 12, a plate-like heat insulating board formed of ceramic fibers is used. Moreover, the heat insulating material 12 is comprised by the laminated body on which three heat insulation boards were laminated | stacked.

  The furnace chamber 11 is a firing chamber for containing a firing target. The furnace chamber 11 has an opening 111 on the front surface, and has a substantially rectangular parallelepiped shape. The heat insulating material 12 is disposed on the upper surface, the lower surface, the left side surface, the right side surface, and the back surface of the furnace chamber 11. At the front of the furnace body 10, an operation panel 6 on which a power switch and the like are arranged is provided.

  The furnace door 2 is composed of a door main body 20, a heat insulating material 21 facing the furnace chamber 11, and holding plates 22 and 23 for holding the heat insulating material 21, and is a front door arranged at the front of the furnace main body 10. is there. The furnace door 2 is attached to the furnace body 10 via a hinge 5 provided at the left end of the door body 20.

  Further, the furnace door 2 is fixed to the furnace body 10 in a closed state by the lock portion 4 provided at the right end portion of the door body 20. The door main body 20 is a box-like outer frame that accommodates the heat insulating material 21 and the holding plates 22 and 23. At the right end of the front surface of the door main body 20, a handle portion 3 for opening and closing is provided.

  The heat insulating material 21 is a second heat insulating material disposed in the door main body 20. For example, as the heat insulating material 21, a heat insulating board similar to the heat insulating material 12 is used. Moreover, the heat insulating material 21 is comprised by the laminated body on which three heat insulation boards were laminated | stacked. The heat insulation board of the furnace door 2 is rectangular.

  The holding plates 22 and 23 are divided holding members attached to the door main body 20 respectively, and are respectively positioned at different end faces of the heat insulating material 21. The holding plate 22 holds the left and right sides of the heat insulating material 21 and is disposed on the left end surface and the right end surface of the heat insulating material 21 respectively. On the other hand, the holding plate 23 holds the upper and lower sides of the heat insulating material 21 and is disposed on the upper end surface and the lower end surface of the heat insulating material 21 respectively. With the heat insulating material 21, the peripheral portion of the back surface 212 facing the furnace chamber 11 contacts the heat insulating material 12 when the furnace door 2 is closed.

<Furnace door 2>
FIG. 3 is an external view showing the back of the furnace door 2. FIG. 4: is sectional drawing which shows the cut surface at the time of cut | disconnecting the furnace door 2 of FIG. 3 by BB cutting line. FIG. 4 shows the case where the cut surface is viewed from the direction of the arrow. FIG. 5 is an exploded perspective view of the furnace door 2 of FIG.

  The door main body 20 includes a front plate 200 facing the front surface 211 of the heat insulating material 21 and a side frame portion 201 surrounding the heat insulating material 21 in a vertical plane, an upper frame portion 202, and a lower frame portion 203. The front plate 200, the side frame portion 201, the upper frame portion 202, and the lower frame portion 203 are integrally formed by bending or pressing a metal plate.

  The side frame portion 201 is a peripheral portion facing the left end surface or the right end surface of the heat insulating material 21 and extends in the vertical direction. The upper frame portion 202 is a peripheral portion facing the upper end surface of the heat insulating material 21 and extends in the left-right direction. The lower frame portion 203 is a peripheral portion facing the lower end surface of the heat insulating material 21 and extends in the left-right direction.

  The holding plate 22 is attached to the side frame portion 201 of the door main body 20 using a fastening part 24 such as a screw. The holding plate 22 disposed on the right side is attached to the side frame portion 201 on the right side. On the other hand, the holding plate 22 disposed on the left side is attached to the side frame portion 201 on the left side. That is, the right holding plate 22 and the left holding plate 22 are disposed opposite to each other with the heat insulating material 21 interposed therebetween in the left-right direction.

  The holding plate 23 disposed on the upper side is disposed between the upper frame portion 202 of the door main body 20 and the upper end surface of the heat insulating material 21. On the other hand, the holding plate 23 disposed on the lower side is disposed between the lower frame portion 203 of the door main body 20 and the lower end surface of the heat insulating material 21. That is, the upper holding plate 23 and the lower holding plate 23 are disposed to face each other with the heat insulating material 21 interposed therebetween in the vertical direction.

  The holding plates 22 and 23 constitute an inner frame surrounding the heat insulating material 21. The back surface 212 of the heat insulating material 21 is provided with one step by reducing the thickness of the peripheral portion. The step extends along the end face of the heat insulating material 21 and surrounds the opening 111 of the furnace chamber 11.

<Retaining plate 22>
FIG. 6 is an external view showing one configuration example of the holding plate 22 of FIG. FIG. 7 is a cross-sectional view showing a cross section of the holding plate 22 of FIG. 6 taken along the line C-C. FIG. 7 shows the case where the cut surface is viewed from the direction of the arrow.

  The holding plate 22 includes a side plate 221, a plate spring 222, a support portion 223, and an attachment portion 225. The side plate 221 is a flat plate that faces the end face of the heat insulating material 21 and extends in the vertical direction.

  The plate spring 222 is a biasing member that contacts the peripheral portion of the front surface 211 of the heat insulating material 21 and biases the heat insulating material 21 toward the furnace chamber 11. The plate spring 222 extends from the front end of the side plate 221 toward the door main body 20 more than the heat insulating material 21, and contacts the peripheral edge of the front surface 211 of the heat insulating material 21. In addition, the plate spring 222 contacts the heat insulating material 21 at the center side of the heat insulating material 21 than the support portion 223.

  The contact position of the plate spring 222 with the heat insulating material 21 is formed at a position overlapping the contact area of the heat insulating material 21 of the furnace door 2 and the heat insulating material 12 of the furnace main body 10 as viewed from the front and rear direction. That is, the plate spring 222 contacts the position on the front surface 211 of the heat insulating material 21 corresponding to the position on the back surface 212 of the heat insulating material 21 in contact with the heat insulating material 12.

  The support portion 223 is a claw member for sandwiching the heat insulating material 21 together with the plate spring 222, extends from the rear end of the side plate 221 to the furnace chamber 11 side of the heat insulating material 21 and contacts the peripheral portion of the back surface 212 of the heat insulating material 21. Do. The side plate 221, the plate spring 222 and the support portion 223 are integrally formed by bending or pressing a metal plate.

  The attachment portion 225 is a plate member for fixing the side plate 221 to the side frame portion 201 of the door main body 20, and is attached to the side plate 221. The mounting portion 225 has a shape extending from the rear end of the side plate 221 to the opposite side to the support portion 223, and is provided with a through hole 226 for allowing the fastening component 24 to pass therethrough.

  The holding plate 22 is provided with a slit 224 extending in the direction from the tip of the plate spring 222 to the end face of the heat insulating material 21. The slit 224 is a notch extending in a direction perpendicular to the end face of the heat insulating material 21, that is, in the left-right direction. Four slits 224 are formed in the holding plate 22 at regular intervals in the vertical direction. The slits 224 may be inclined with respect to the end face of the heat insulating material 21.

  The support portion 223 of the holding plate 22 contacts the back surface 212 of the heat insulating material 21 on the end face side of the heat insulating material 21 more than the step of the heat insulating material 21 described above. On the other hand, the plate spring 222 of the holding plate 22 contacts the front surface 211 of the heat insulating material 21 at the center side of the step. The cross-sectional shape of the plate spring 222 is an S-shaped curve. The slit 224 is formed to a position deeper than the S-shaped root of the plate spring 222.

  Although the shape of the holding plate 22 has been described with reference to FIGS. 6 and 7, the shape of the holding plate 23 is the same as that of the side plate 221 of the holding plate 22, the plate spring 222, and the support 223. That is, the holding plate 23 is configured of a side plate, a plate spring, and a support. The side plate of the holding plate 23 is a flat plate that faces the end face of the heat insulating material 21 and extends in the left-right direction.

  The plate spring of the holding plate 23 is a biasing member that contacts the peripheral portion of the front surface 211 of the heat insulating material 21 and biases the heat insulating material 21 rearward. The leaf spring extends from the front end of the side plate toward the door main body 20 more than the heat insulating material 21, and contacts the peripheral edge of the front surface 211 of the heat insulating material 21. The supporting portion of the holding plate 23 is a claw member for sandwiching the heat insulating material 21 together with the plate spring, extends from the rear end of the side plate to the furnace chamber 11 side more than the heat insulating material 21. Contact.

  These side plates, leaf springs and support portions are integrally formed by bending or pressing a metal plate. However, the holding plate 23 has no attachment portion for fixing the side plate to the upper frame portion 202 or the lower frame portion 203 of the door main body 20. Further, the holding plate 23 has no slit.

  Movement of the holding plate 22 in the front-rear direction is restricted by fixing the mounting portion 225 to the side frame portion 201 of the door main body 20 using the fastening component 24. For this reason, when the furnace door 2 is closed and the heat insulating material 21 of the furnace door 2 is pressed against the heat insulating material 12 of the furnace main body 10, the heat insulating material 12 is pushed forward by the heat insulating material 12; Only 12 moves forward. Even in such a situation, the plate spring 222 of the holding plate 22 biases the heat insulating material 21 rearward with a predetermined pressing force against the door main body 20, so that the degree of sealing of the furnace chamber 11 can be maintained. .

  On the other hand, the holding plate 23 is not fixed to the upper frame portion 202 or the lower frame portion 203 of the door main body 20. For this reason, the holding plate 23 is not a biasing means for biasing the heat insulating material 21 toward the furnace chamber 11 with respect to the door main body 20.

  Each component which comprises the baking furnace 1 by this Embodiment is as having mentioned above. In the following, the relationship between these parts and the effects produced thereby will be described in detail.

(1) Improvement of sealing degree The heat insulating material 21 of the furnace door 2 closes the opening of the furnace chamber 11 in a state where the furnace door 2 is closed, and the heat insulating material 12 of the furnace main body 10 at the peripheral portion of the furnace chamber opening Contact. Further, the heat insulating material 21 is urged toward the furnace chamber 11 by the plate spring 222 of the holding plate 22. In the baking furnace 1 according to the present embodiment, the heat insulating material 21 is pressed against the heat insulating material 12 by the action of the plate spring 222, and the degree of sealing of the furnace chamber 11 can be enhanced.

  In particular, in the firing furnace 1 according to the present embodiment, the pressing force is appropriate when the plate spring 222 is in contact with the heat insulating material 21 on the center side of the heat insulating material 21 with respect to the support 223. Is obtained. Further, since the plurality of divided holding members urge the heat insulating material 21 uniformly along the peripheral edge of the heat insulating material 21, the heat insulating material 12 of the furnace main body 10 can be pressed. Further, since the holding plate 22 is disposed to face each other with the heat insulating material 21 interposed therebetween, the heat insulating material 21 of the furnace door 2 can be pressed to the heat insulating material 12 of the furnace main body 10 in a balanced manner.

  Further, in the firing furnace 1 according to the present embodiment, the pressing force applied by the plate spring 222 of the holding plate 22 to the front surface 211 of the heat insulating material 21 can be adjusted by the number and size of the slits 224. For this reason, the heat insulating material 21 of the furnace door 2 can be more uniformly pressed against the heat insulating material 12 of the furnace main body 10.

(2) Ease of manufacture The assembly of the furnace door 2 is performed as follows. First, two holding plates 22 and two holding plates 23 are respectively attached to the upper, lower, left, and right end faces of the heat insulating material 21. Next, the heat insulating material 21 is accommodated in the door main body 20 with the holding plates 22 and 23 attached. The furnace door 2 is completed by fixing the mounting portion 225 of the holding plate 22 to the side frame portion 201 of the door main body 20 using the fastening component 24.

  In the firing furnace 1 according to the present embodiment, since the biasing member is integrated with the holding plate 22 as the plate spring 222, the number of parts is reduced as compared with the case where the biasing member is a separate member from the holding member, Manufacturing can be facilitated. In particular, since the holding members are constituted by two or more holding plates 22 and 23 attached respectively to the door main body 20, the holding plates 22 and 23 are attached to the heat insulating material 21 and accommodated in the door main body 20. The furnace door 2 is completed only by screwing 23 from the back side. For this reason, a holding member is comprised by one frame which surrounds the heat insulating material 21, and assembly of the furnace door 2 is facilitated compared with the case where the fastening component which wound the coiled spring is attached to a holding member. Moreover, replacement of the heat insulating material 21 is easy.

(3) Suppression of Heat Leakage In the firing furnace 1 according to the present embodiment, since the plate spring 222 contacts the peripheral portion of the heat insulating material 21, the biasing member does not have to be in contact with the central portion where the temperature is high. Leakage of heat from the heat insulating material 21 to the door main body 20 can be suppressed.

(4) Crack prevention of heat insulation material The peripheral part of back 212 of heat insulation material 21 of furnace door 2 contacts heat insulation material 12 of furnace main part 10. On the other hand, the plate spring 222 of the holding plate 22 contacts the peripheral portion of the front surface 211 of the heat insulating material 21. For this reason, in the baking furnace 1 according to the present embodiment, the peripheral portion in contact with the heat insulating material 12 is pressed, and the heat insulating material 21 is deformed as compared with the case where the biasing member is in contact with the central portion of the heat insulating material 21. Or damage can be suppressed.

  The heat insulating material 21 is deteriorated and easily broken by repeating the normal temperature state and the high temperature state in which the temperature is higher than the normal temperature. In the baking furnace 1 according to the present embodiment, the heat insulating material 21 is made less likely to be broken, thereby preventing the leakage of heat.

(5) Space saving In the firing furnace 1 according to the present embodiment, the holding member is constituted by the plate spring 222, the side plate 221, and the support portion 223. Therefore, the space for disposing the biasing member outside the side plate 221 And the furnace door 2 can be prevented from increasing in size.

(6) Facilitation of Response to Thermal Expansion The heat insulating material 12 of the furnace body 10 expands by heating, and pushes the furnace door 2 forward. In the conventional baking furnace, it was necessary to provide a play in the hinge 5 to absorb the movement of the furnace door 2. On the other hand, in the baking furnace 1 according to the present embodiment, since the leaf springs 222 of the holding plate 22 allow the heat insulating material 21 to move forward, it is not necessary to provide the hinge 5 with a play.

  In the present embodiment, an example in which the left and right end portions of the heat insulating material 21 are biased toward the furnace chamber 11 by the holding plate 22 has been described, but the present invention relates to the configuration of the holding member It is not limited. For example, the holding plate 23 holding the upper and lower ends of the heat insulating material 21 has the same function as the holding plate 22 and the upper and lower ends of the heat insulating material 21 are biased toward the furnace chamber 11 by the holding plate 23 It may be of such a configuration. Further, even if one frame body surrounding the heat insulating material 21 is used as a holding member, a plate spring for biasing the heat insulating material 21 toward the furnace chamber 11 is provided on two or more sides of the frame body. good.

  Moreover, although the example of the horizontal lid type baking furnace 1 was demonstrated in this Embodiment, this invention is applicable also to a top lid type baking furnace. In the present embodiment, an example in which the shape of the opening 111 of the furnace chamber 11 is rectangular and the shape of the heat insulating material 21 of the furnace door 2 is also rectangular has been described. And the shape of the heat insulating material 21 is not limited to this. For example, the shape of the opening 111 of the furnace chamber 11 may be octagonal, dodecagonal or circular.

DESCRIPTION OF SYMBOLS 1 burning furnace 10 furnace main body 11 furnace room 111 opening 12, 21 heat insulating material 2 furnace door 20 door main body 200 front plate 201 side frame 202 upper frame 203 upper frame 203 lower frame 22, 23 holding plate 221 side plate 222 flat spring 223 support Part 224 Slit 225 Attachment part 24 Fastening parts 5 Hinge

Claims (8)

A furnace body having a furnace chamber surrounded by a first heat insulating material,
And a furnace door which is attached to the furnace body so as to be openable and closable and closes an opening of the furnace chamber,
The furnace door includes a door main body, a second heat insulating material facing the furnace chamber, and a holding member holding the second heat insulating material.
When the furnace door is closed, the second heat insulating material is in contact with the first heat insulating material with the peripheral edge portion of the back surface facing the furnace chamber.
The said holding member contacts the peripheral part of the front surface of the said 2nd heat insulating material, and has a leaf | plate spring which biases the said 2nd heat insulating material toward the said furnace chamber, The baking furnace characterized by the above-mentioned. The holding member extends from the rear end of the side plate to the furnace chamber side of the second heat insulating material from the rear end of the side plate and contacts the peripheral edge of the back surface of the second heat insulating material. And a support portion,
2. The furnace according to claim 1, wherein the leaf spring extends from the front end of the side plate toward the door main body more than the second heat insulating material, and contacts the peripheral portion of the front surface of the second heat insulating material.   The said plate spring contacts the said 2nd heat insulating material in the center side of the said 2nd heat insulating material rather than the said support part, The baking furnace of Claim 2 characterized by the above-mentioned.   The plate spring is in contact with a position on the front surface of the second heat insulating material corresponding to a position on the back surface of the second heat insulating material in contact with the first heat insulating material. The burning furnace as described in any.   The said holding member is comprised by the 2 or more division | segmentation holding member each attached to the said door main body, and the said division | segmentation holding member is located in the different end surface of the said 2nd heat insulating material, respectively. The burning furnace as described in any.   The said division holding member is opposingly disposed on both sides of the said 2nd heat insulating material, The baking furnace of Claim 5 characterized by the above-mentioned.   The firing furnace according to claim 5 or 6, wherein the divided holding member has a slit extending in a direction from an end of the plate spring to an end face of the second heat insulating material. The second heat insulating material has a rectangular shape,
The said dividing holding member hold | maintains at least one side of the said 2nd heat insulating material, The baking furnace in any one of the Claims 5-7 characterized by the above-mentioned.

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