JP2018134761A - Method for producing ceramic molded body and ceramic molded body production device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a ceramic molded body and a ceramic molded body production device capable of increasing a degree at which the cross-sectional shape of a ceramic molded body recovers to a true circular shape and further swiftly drying the same.SOLUTION: Provided is a method for producing a ceramic molded body where a ceramic molded body 9 of 1.5 m or higher is arranged on a rotary roller 51 and is dried while being rotated. Then, upon the drying, the drying is performed in such a manner that ventilation is performed from the rear end side (root side) in the extrusion direction of the ceramic molded body 9 toward the tip side. In the ceramic molded body 9, immediately after being extruded, since the rear end side has a high true circle degree after that, by performing the ventilation from the rear end side of the ceramic molded body 9 toward its tip side, the rear end side can be dried early. Meanwhile, since the tip side is gradually collapsed by dead weight, while rotating the ceramic molded body 9, ventilation is performed from the rear end side of the ceramic molded body 9 toward its tip side.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method for manufacturing a ceramic molded body and an apparatus for manufacturing a ceramic molded body that can be applied to, for example, a cylindrical horizontal stripe type solid oxide fuel cell.

  Conventionally, a cylindrical horizontal stripe type solid oxide fuel cell is known as a solid oxide fuel cell. This cylindrical horizontal stripe type solid oxide fuel cell is a porous cylindrical insulator base tube (that is, a support) in which a large number of fuel cells are arranged side by side with an interconnector between them. Connected.

  The support of the cylindrical horizontal stripe type solid oxide fuel cell is usually formed using, for example, a clay-like extruded material, extruded into a cylindrical shape using an extruder, and cut to a desired length (that is, a ceramic body). (Molded body) is produced, and this is naturally left to dry or heat dried, and then fired.

  Of these, cutting is generally performed with a wire. For example, there is a method in which the wire is moved up and down in the vicinity of the die of the extrusion molding machine, and there is also a method in which the wire diameter is reduced in order to reduce the resistance applied at the time of cutting (see Patent Document 1 below). .

In addition, there are a method of correcting the shape of the ceramic molded body when the deformation occurs (see Patent Document 2 below) and a method of discarding the deformed portion of the ceramic molded body after drying.
Furthermore, in the case of a long cylindrical shape in which the length of the ceramic molded body exceeds 1.5 m, the tip of the ceramic molded body takes time from being extruded until it is cut, so it is crushed by its own weight. The cross section becomes elliptical.

  As a countermeasure against this, there is known a technique in which a ceramic molded body is rotated on a rotating roller and naturally dried while the cross-sectional shape of the ceramic molded body is restored to a certain degree of perfect circle (see Patent Documents 3 and 4 below).

  In addition, when drying a cylindrical ceramic molded body, there is a technology for uniformly drying the outside and inside of the ceramic molded body by sending air to the through hole at the center of the axis of the ceramic molded body that has been stationary. It is known (see Patent Document 5 below).

JP 2002-103324 A JP 2006-205526 A JP 2003-26466 A JP 2003-117717 A JP-A-6-335910

  However, in the above-described prior art, when drying by blowing while rotating with respect to the ceramic molded body after cutting, drying is promoted, but when the curing of the clay proceeds excessively, the aforementioned cross-sectional shape is a perfect circle shape. There is a risk of hindering recovery.

Insufficient recovery to the perfect circle shape is not preferable because it causes trouble when the ceramic molded body is processed while being rotated in a subsequent printing process or the like.
On the other hand, when delaying the start of drying of the ceramic molded body and emphasizing the recovery of the above-described cross-sectional shape to a perfect circle shape, the time required for sufficient drying becomes longer. Further, in an apparatus that transports while drying, the transport distance becomes long, and the apparatus becomes huge.

  In addition, when drying is inadequate, there exists a problem that the intensity | strength of a ceramic molded body will run short and handling will deteriorate in a subsequent baking process etc., or a failure | damage may occur depending on the case.

  The present invention has been made in order to solve the above-described problems, and the object thereof is to increase the degree to which the cross-sectional shape of the ceramic molded body recovers to a perfect circular shape (hereinafter referred to as “recovery degree”) and quickly. Another object of the present invention is to provide a method for producing a ceramic molded body and an apparatus for producing a ceramic molded body that can be dried.

(1) 1st aspect of this invention is related with the manufacturing method of the ceramic molded body which manufactures the cylindrical ceramic molded body whose axial direction length is 1.5 m or more.
This method of manufacturing a ceramic molded body includes an extrusion molding process for producing an extruded molded body by extrusion molding, a cutting process for producing a ceramic molded body by cutting the extruded molded body into a predetermined length, and rotating the ceramic molded body. A drying step of blowing and drying a plurality of ceramic molded bodies that rotate on a plurality of rotatable rollers that can be conveyed from the rear end side toward the front end side in the extrusion direction of the ceramic molded body. .

  In the first aspect, the ceramic molded body is placed on a rotating roller and dried while rotating. And in this drying, it blows and drys toward the front end side from the rear end side (namely, root side) in the extrusion direction of a ceramic molded body.

  The tip side of the ceramic molded body has elapsed since being extruded, and gradually collapses due to its own weight. Therefore, it takes time to recover the perfect circular shape by rotating the ceramic molded body.

On the other hand, the rear end side of the ceramic molded body is immediately after being extruded and substantially maintains its shape. That is, the back end side of the ceramic molded body has a high degree of perfect circle.
Therefore, in the first aspect, air is blown from the rear end side to the front end side of the ceramic molded body while rotating the ceramic molded body. Thereby, while it is possible to dry from the rear end side where the degree of perfect circle is high, the tip side can be dried after increasing the degree of recovery, and a ceramic molded body with a high degree of perfect circle can be efficiently obtained. Can be obtained.

  In addition, since the moisture volatilized from the material (that is, clay) of the ceramic molded body is sent to the front end side by the blowing, the atmosphere on the front end side changes (that is, the humidity increases). . Therefore, also from this point, since the flexibility of the material on the tip side can be maintained for a long time, the degree of recovery can be increased by rotating during this period.

  In this way, in the first aspect, there is a remarkable effect that the ceramic molded body can be quickly dried while ensuring the degree of recovery of the cross-sectional shape. In addition, this makes it easy to work while rotating the ceramic molded body, and there is an advantage that the apparatus can be made compact in an apparatus that conveys the ceramic molded body while drying it.

In particular, when the ceramic molded body has a length of 1.5 m or more, crushing on the tip side due to its own weight is significant, and the shape recovery step is essential.
Moreover, in this 1st aspect, the component of rotating rollers, such as iron, is hard to adhere to a ceramic molded object by shortening drying time. Therefore, it is possible to suppress a decrease in performance of the ceramic molded body due to the adhered substance. For example, when a ceramic molded body is fired to form a sintered body and then a film is formed on the surface, the film can be suitably formed on the surface of the sintered body.

  Here, the ceramic molded body is formed by extruding and cutting a material of a ceramic molded body (for example, clay), and has a softness that can be shaped by a rotating roller before drying. , A molded body that cures by drying (thus, a molded body before firing).

  Moreover, in this 1st aspect, after rotating a ceramic molded object, ventilation can be started at a predetermined timing. As a timing (timing) for starting the blowing, an appropriate timing after the ceramic molded body is rotated can be adopted. By adjusting this timing, it is possible to dry quickly while realizing a high degree of recovery of the cross-sectional shape.

  In addition, when the timing of a ventilation start is early, quick drying is realizable, and when the timing of ventilation is late, the high recovery | restoration degree of cross-sectional shape is realizable. As for the wind speed in the case of the said ventilation, 0.5 m / s or more is desirable.

  Furthermore, it is preferable that the blowing is started after the roundness of the ceramic molded body is restored to 70% or less by the rotation. Thereby, it can dry quickly, implement | achieving the high recovery degree of cross-sectional shape.

  Here, the roundness ratio [%] is the degree of the perfect circle of the ceramic molded body, which is the longest diameter when the ceramic molded body is viewed from the extrusion direction (that is, the axial direction) (that is, the maximum through hole extending in the axial direction). (Diameter) and a short diameter (that is, the minimum diameter of the through-hole), and are expressed by the following formula (1).

Roundness rate [%] =
{(Difference between major axis and minor axis after drying for a certain period of time / Difference between major axis and minor axis immediately after molding)} × 100 (1)
Here, the “certain time” is the time from when the extruded molded body is cut to the start of blowing, and “immediately after molding” is the time when the extruded molded body is cut into a ceramic molded body. .

In addition, when the perfect circle ratio is small, it can be regarded that the true circle has been sufficiently recovered immediately after extrusion when it is close to a perfect circle, for example, when it is 60% or less.
The roundness varies depending on the measurement position in the extrusion direction. Usually, the roundness on the front end side in the extrusion direction is larger than that on the rear end side, and its value increases with time.

  (2) A second aspect of the present invention is the method for manufacturing a ceramic molded body according to the first aspect, wherein the cutting step is a step of cutting the extruded molded body with a cutting blade, and the cutting process of the extruded molded body. The cutting load is controlled by changing the speed of the cutting blade.

If the load for cutting the extruded molded body is too large, the ceramic molded body after cutting may be deformed and the amount of deformation may be increased.
On the other hand, in the second aspect, the amount of deformation of the ceramic molded body can be reduced by controlling the load applied to the press-formed body during cutting (that is, the cutting load). Specifically, as will be apparent from experimental examples described later, the amount of deformation of the ceramic molded body can be reduced by reducing the cutting load (for example, by reducing it to a predetermined value or less).

  As a result, since the degree of the perfect circle on the rear end side of the ceramic molded body can be kept high, it is also suitable for drying by blowing air from the rear end side to the front end side while rotating the ceramic molded body. .

  Further, the deformation amount is a deformation amount on the rear end side of the cut ceramic molded body, but the front end side of the extruded molded body left after the cutting is similarly deformed. Therefore, the tip side of the ceramic molded body from which the extruded molded body is cut is also deformed. As a result, there is also an effect that the deformation of the tip side of the ceramic molded body can be suppressed.

  (3) A third aspect of the present invention is a method for manufacturing a ceramic molded body according to the first or second aspect, and in the extrusion molding step, a molding die for molding the extruded molded body includes an outer die, An inner die having a tip projecting in the extrusion direction from the tip of the outer die, and in the cutting step, the cutting blade is moved from the outer peripheral side of the inner die toward the inner die to cut the extrusion molded body. .

  In the prior art, when a ceramic molded body is cut with a wire, the ceramic molded body is deformed because it is crushed at the beginning of cutting or pulled at the end of cutting. In particular, when the ceramic molded body has a cylindrical shape, it cannot be supported by the surface, and is easily deformed. For this reason, in the subsequent drying process, printing process, etc., there may be a problem when the ceramic molded body is processed while being rotated.

  On the other hand, in the third aspect, a cylindrical extrusion molded body (for example, ceramic) is formed by extrusion molding using a molding die having an inner die (inner die) and an outer die (outer die). Extruded product made of material) is formed. And with respect to this extrusion molded body, the cutting blade is moved from the outer peripheral side of the inner die toward the inner die to cut the extrusion molded body, so that deformation during cutting can be suppressed.

  That is, in the third aspect, since the inner die protrudes downstream in the extrusion direction from the outer die, a part of the front end side of the extruded molded body is located on the outer peripheral side of the inner die. Therefore, when the cutting blade is pushed into (pressed into) the extrusion molded body positioned on the outer peripheral side, an inner die is provided to support the extrusion molded body from the inside in the direction of pushing the cutting blade. Therefore, since the extrusion molded body does not deform to the inner side (axis center side) from the inner die, deformation of the extrusion molded body during cutting (and hence deformation of the ceramic molded body after cutting) is suppressed.

  Further, since the deformation of the ceramic molded body is suppressed at the time of cutting, there is an advantage that it is possible to reduce work such as cutting the deformed portion of the end portion again after drying and curing the ceramic molded body, and to reduce material loss and the like. .

  The material of the cutting blade is preferably made of a material softer than the material of the inner die. Thereby, even when the cutting blade hits the inner die, there is an effect that the deformation and damage of the inner die are small, and therefore the dimensional accuracy of the ceramic molded body is hardly lowered.

(4) A fourth aspect of the present invention relates to a ceramic molded body manufacturing apparatus for manufacturing a cylindrical ceramic molded body having an axial length of 1.5 m or more.
This ceramic molded body manufacturing apparatus includes an extrusion molding machine that produces an extruded molded body by extrusion molding, a cutting machine that cuts the extruded molded body into a predetermined length to produce a ceramic molded body, and a rotating ceramic molded body. A plurality of rotating rollers that can be transported and a blower that blows air from the rear end side to the front end side in the extrusion direction of the ceramic molded body and dries the plurality of ceramic molded bodies that rotate on the rotating roller. And comprising.

The fourth aspect has the same effects as the first aspect.
(5) A fifth aspect of the present invention is the ceramic molded body manufacturing apparatus according to the fourth aspect, wherein the cutting machine has a cutting blade for cutting the extruded molded body, and in the cutting process of the extruded molded body. A mechanism for controlling the cutting load is provided by changing the speed of the cutting blade.

The fifth aspect has the same operational effects as the second aspect.
(6) A sixth aspect of the present invention is the ceramic molded body manufacturing apparatus according to the fourth or fifth aspect, wherein the extrusion molding machine has the tip of the inner die protruding in the extrusion direction from the tip of the outer die. The cutting machine is provided with a molding die, and the cutting machine has a cutting blade for cutting the extrusion molded body extruded from the molding die, and the cutting blade moves from the outer peripheral side of the inner die toward the inner die. It has a mechanism for cutting.

  The sixth aspect has the same operational effects as the third aspect.

  According to the present invention, a cylindrical ceramic molded body having an end portion with little deformation is obtained. Further, by blowing air from the base side of the ceramic molded body, the ceramic molded body can be dried in a short time while obtaining the self-weight crush recovery effect on the tip side.

<Each configuration of the present invention will be described below>
The ceramic molded body is a cylindrical member having ceramic as a main component (that is, the maximum content of solid components). Examples of the ceramic type include alumina, zirconia, mullite, and spinel. In addition to ceramics, other components such as glass may be included.

  -An extrusion molding is a cylindrical (for example, cylindrical shape) molded body which has ceramic as a main component and was formed by extruding an extrusion material (for example, clay) having a predetermined viscosity by an extruder. In addition, since this extrusion molded object is a molded object before the cutting | disconnection of a ceramic molded object, the material is the same as that of a ceramic molded object.

-A cutting blade is a member for cutting which cuts an extrusion-molded body and forms a ceramic molded body, for example, a plate-like member made of resin or metal.
A molding die is a die that molds an extruded product from an extruded material (for example, clay) having a predetermined viscosity. The outer die is a cylindrical mold that forms the outer peripheral surface of the extruded molded body, and the inner die is a mold that is disposed on the axial center side of the outer die and forms the inner peripheral surface of the extruded molded body. is there.

  A rotating roller is a roller that can rotate around the axis center, and is a roller that can carry a ceramic molded body as a part of a conveyor or the like by mounting the ceramic molded body on itself. . Examples of the material of the rotating roller include metals such as iron and aluminum, and materials such as ceramic.

It is a front view which shows the manufacturing apparatus of 1st Embodiment. It is a top view which shows a manufacturing apparatus. It is a perspective view which shows a ceramic molded object. It is explanatory drawing which shows the arrangement | positioning of a cutting machine while cut | disconnecting and showing a shaping | molding metal mold | die in the perpendicular direction. It is explanatory drawing which shows the state which looked at the cutting machine, the inner die | dye, etc. from the front-end | tip of the extrusion direction. It is explanatory drawing which shows the state which looked at the mounting part, the cutting machine, a part of conveyor, etc. from the front-end | tip of the extrusion direction. It is a flowchart which shows the cutting process by a cutting machine. It is explanatory drawing which shows a part of manufacturing process of a ceramic molded body. It is explanatory drawing which shows the state which looked at the cutting machine in 2nd Embodiment, an internal die, etc. from the front-end | tip of the extrusion direction. It is explanatory drawing which shows the state which looked at the cutting machine in 3rd Embodiment, an internal die, etc. from the front-end | tip of the extrusion direction. It is a graph which shows an experimental result.

Next, embodiments of the method for manufacturing a ceramic molded body and the apparatus for manufacturing a ceramic molded body according to the present invention will be described.
[1. First Embodiment]
[1-1. Configuration of manufacturing apparatus for ceramic molded body]
First, a ceramic molded body manufacturing apparatus (hereinafter simply referred to as a manufacturing apparatus) used in the ceramic molded body manufacturing method of the first embodiment will be described.

  As shown in FIG.1 and FIG.2, the manufacturing apparatus 1 of 1st Embodiment mainly has the extrusion machine 5 which performs the extrusion molding of the extrusion molding 3, and the cutting machine 7 which cuts the extrusion molding 3, The mounting part 11 (refer FIG. 2) which mounts the cut | disconnected ceramic molded object 9 (refer FIG. 3), the conveyor 13 which conveys the ceramic molded object 9, and the air blower 15 which ventilates the ceramic molded object 9 (FIG. 2). The conveyor 13 and the blower 15 constitute a rotary dryer 16.

  Among these, as shown in FIG. 2, the cutting machine 7 is disposed on the distal end side (right side in FIG. 2) of the extrusion molding machine 5, and the mounting portion 11 is disposed on the distal end side of the cutting machine 7. Yes. The conveyor 13 is disposed parallel to the ground in one lateral direction (upper side in FIG. 2) of the placement unit 11, and the blower 15 is perpendicular to the conveyance direction (arrow B direction) of the conveyor 13. Are arranged on one side (left side in FIG. 2).

Hereinafter, each configuration will be described in detail.
<Extruder>
The extrusion molding machine 5 is an apparatus for extruding a cylindrical (that is, cylindrical) 3 and includes a cylindrical cylinder 17 and a molding die 19 disposed on the tip side of the cylinder 17.

  The ceramic molded body 9 formed by cutting the extruded molded body 3 has a cylindrical shape, and the ceramic molded body 9 is formed with a cylindrical through-hole 9a (see FIG. 3) extending along the center of the axis. ing.

  Here, the dimensions of the ceramic molded body 9 are, for example, 2.0 m in the range of 1.5 m to 2.5 m in length, for example 25 mm in the range of outer diameter 15 mm to 30 mm, and 20 mm in the range of inner diameter 10 mm to 30 mm, for example. Can be adopted.

  Among these, an extrusion screw (not shown) is arranged inside the cylinder 17 coaxially with the cylinder 17. This extrusion screw is a screw that pushes clay filled in the cylinder 17 in the extrusion direction (right direction in FIG. 1: arrow A direction) by rotation.

  Further, as shown in FIG. 4, the molding die 19 is coaxial with the outer die 21 inside the cylindrical outer die 21 disposed coaxially with the cylinder 17 and inside the outer die 21 (that is, on the axial center side). And a cylindrical inner die 23 arranged on the inner side.

The outer die 21 has an inner diameter of φ12 mm, for example, and the outer peripheral surface of the ceramic molded body 9 is formed by the inner peripheral surface of the outer die 21.
On the other hand, the inner die 23 has an outer diameter of φ9.8 mm, for example, and the inner peripheral surface of the ceramic molded body 9 is formed by the outer peripheral surface of the inner die 23.

The inner die 23 is partly covered with the outer die 21 at its outer peripheral surface, and the tip of the inner die 23 protrudes, for example, 10 mm tip side (right side in FIG. 4) from the tip of the outer die 21. .
The inner die 23 and the outer die 21 are made of, for example, a metal material such as stainless steel. When the metal material is, for example, SUS304, the hardness is HB160.

<Cutting machine>
As shown in FIG. 5, the cutting machine 7 is an apparatus that cuts the extruded body 3 extruded from the extruder 5 perpendicular to the extrusion direction.

  The cutting machine 7 detects a pair of upper and lower cutting blades 25 (25a, 25b), each driving device 27 (27a, 27b) that drives each cutting blade 25 in the vertical direction, and a load applied to each cutting blade 25. A load sensor 29 (29a, 29b) and a control device 31 for controlling the operation of the drive device 27 are provided.

  The control device 31 is an electronic control device provided with a known microcomputer or the like, and controls the operation of each drive device 27 based on a signal from each load sensor 29 to control the speed of each cutting blade 25. . Thereby, the load which each cutting blade 25 applies to the extrusion molding 3 is controlled, and the cutting state of the extrusion molding 3 is adjusted. As the driving device 27, a device using a known motor, air pressure, or the like can be adopted.

  Each cutting blade 25 is a plate material made of nylon (for example, MC nylon: registered trademark) having a thickness of 2 mm, for example. The hardness of the cutting blade 25 made of nylon is Rockwell hardness R120. Therefore, the cutting blade 25 is softer than the inner die 23.

  In addition, semicircular cutting edges 33a and 33b (33) are formed on the distal end side (inner die 23 side) of each cutting blade 25, respectively. The cutting edge 33 is a portion that cuts the extruded molded body 3 and has a shape that abuts the outer peripheral surface of the inner die 23 in a circumferential direction (that is, surrounds) after cutting. Specifically, each cutting edge 33 of each cutting blade 25 has a shape that abuts a half-circumferential portion in the circumferential direction of the outer peripheral surface of the inner die 23. That is, the radius of each cutting edge 33 is the same as the radius of the inner die 23.

  In the cutting machine 7 having such a configuration, the upper cutting blade 25 moves to the axial center O side of the inner die 23, and the cutting edge 33 comes into contact with the outer peripheral surface (that is, the upper semicircular portion) of the inner die 23. At the same time, the lower cutting blade 25 moves to the axial center O side of the inner die 23, and the cutting edge 33 comes into contact with the outer peripheral surface (that is, the lower semicircular portion) of the inner die 23. Disconnect.

<Placement part>
As shown in FIG. 2, the mounting portion 11 has a long and flat upper surface extending in the extrusion direction, and a base 37 on which the extruded product 3 is placed, and a base 37. A moving mechanism 39 that pushes and moves the placed ceramic molded body 9 in the direction of arrow B is provided.

  The moving mechanism 39 includes a long plate member 41 and a pair of drive units (for example, a drive unit driven by a motor, air pressure, or the like) 43 that moves the plate member 41 in the direction of arrow B. Therefore, as shown in FIG. 6, the ceramic molded body 9 can be moved in the transport direction and mounted on the conveyor 13 by moving the plate 41 in the direction of the arrow B by the drive unit 43 in the horizontal direction. .

<Conveyor>
As shown in FIG. 2, the conveyor 13 is a device that has a rectangular shape in plan view and is arranged in parallel with the ground, and is mounted with one or a plurality of ceramic molded bodies 9 and moves in the transport direction.

  As shown in FIG. 6, the conveyor 13 includes a chain 47 in which a number of substantially T-shaped individual members 45 are connected, a drive roller 49 (see FIG. 1) that rotates the chain 47 in the direction of arrow C, Each individual member 45 includes a plurality of 51 attached to the outer peripheral side thereof.

  The rotating roller 51 is a cylindrical member made of metal such as iron, for example, and is arranged horizontally and in parallel as shown in FIG. That is, they are attached so as to extend in the left-right direction in FIG. 2 and be sandwiched between the left and right chains 47.

  Here, the adjacent rotating rollers 51 are arranged at intervals that do not come into contact with each other, and held by the pair of adjacent rotating rollers 51 so that the ceramic molded bodies 9 do not fall, so that the ceramic molded bodies 9 can be rotated. Has been placed. In addition, since the rotation roller 51 is arrange | positioned in parallel, the width | variety of this space | interval is constant in every position in a longitudinal direction.

  As will be described later, the rotating roller 51 rotates the ceramic molded body 9 disposed between the rotating rollers 51 by being rotated by a driving mechanism (not shown). The rotating roller 51 is configured to be transported in the transport direction along with the operation of the conveyor 13 while rotating at the same rotational speed in the same direction.

<Blower device>
As shown in FIG. 2, the blower 15 connects the blower 53 that is a fan that generates wind, the blower 55 that sends the wind from the blower 53 to the ceramic molded body 9, and the blower 53 and the blower 55. A blower tube 56 is provided.

  In addition, a plurality of nozzles 57 are provided at the tip of the air blowing unit 55. Each nozzle 57 is arrange | positioned at predetermined intervals along the conveyance direction so that it can each blow to many ceramic molded objects 9 mounted in the conveyor 13, and its circumference | surroundings.

  Specifically, the nozzles 57 are set in the direction of blowing air in the direction of arrow A, and are arranged at intervals at which the rotating rollers 51 are arranged. Further, the nozzle 57 is not arranged in the entire range along the conveyance direction of the conveyor 13 but is arranged on the rear end side in the conveyance direction in order to perform natural drying at the start of conveyance.

  Specifically, the nozzle 57 is not arranged in the range from the mounting unit 11 to the end of the conveyor 13 (the upper end in FIG. 2) from the mounting unit 11 to about ３ of the conveyor 13, and the conveyor 57 For example, 8 lines are arranged in a range from about 1/3 of 13 to the end.

And from this nozzle 57, it blows | blows toward the front end side from the rear end side in the extrusion direction (namely, toward arrow A direction) with respect to the ceramic molded object 9 and its periphery. That is, the ceramic molded body 9 is dried by blowing air from the nozzle 57 along the extrusion direction.
[1-2. Manufacturing method of ceramic molded body]
Next, a method for manufacturing the ceramic molded body 9 will be described.
<Raw material preparation process>
As a raw material for clay to be the ceramic molded body 9, a ceramic powder, a resin powder, and a liquid component mixed at a predetermined ratio are used as is well known.

The ceramic powder is variously selected depending on the application. For example, zirconia is generally selected as a support for a fuel cell.
Cellulose resin and acrylic resin are generally selected as the resin powder. This resin powder is a binder that changes to a liquid state by mixing liquid components.

As a liquid component, water (pure water) is a main component, and well-known dispersants, lubricants, lubricants, and the like are added thereto.
<Kneading process>
Next, clay is produced by kneading the clay raw material with a kneader. In addition, you may knead | mix with the extrusion molding machine 5. FIG.

<Extrusion process>
Next, as shown in FIG. 1, this clay is put into the cylinder 17 from the hopper 5 a (see FIG. 1) of the extruder 5.

In the cylinder 17, the extrusion screw is rotated to gradually extrude the clay toward the tip side while kneading the clay.
By this extrusion, clay is passed through the molding die 19 to form the cylindrical extruded body 3. The extruded molded body 3 is placed on a base 37 (see FIG. 6) and gradually moves to the distal end side with extrusion.

<Cutting process>
Then, when the extruded molded body 3 is extruded to a predetermined length (for example, 1500 mm or more), the pair of cutting blades 25 of the cutting machine 7 are used to form a ceramic molded body 9 having a length of 1500 mm, for example. Cut at the position (cutting position). Thereby, the ceramic molded body 9 is obtained.

As described above, the cutting machine 7 is equipped with the load sensor 29 for measuring the load applied to the cutting blade 25, and adjusts the speed of the cutting blade 25 while detecting the load at the time of cutting.
Here, for example, a case where cutting is performed by the control shown in FIG. 7 will be described.

In step (denoted as S in the drawing) 100 in FIG. 7, the cutting blade 25 is moved at an initial set speed.
In subsequent step 110, the load applied to the cutting blade 25 is detected by the load sensor 29.

  In subsequent step 120, it is determined whether or not the load applied to the cutting blade 25 is within a predetermined range. If an affirmative determination is made here, the process proceeds to step 140, while if a negative determination is made, the process proceeds to step 130.

  In step 130, the speed of the cutting blade 25 is controlled so that the load applied to the cutting blade 25 falls within the target predetermined range, and the process returns to step 110. For example, when the load is too large, the speed is decreased to reduce the load. Conversely, if the load is too small, increase the speed to increase the load.

  Since there is a certain relationship (for example, a proportional relationship) between the speed of the cutting blade 25 and the load (that is, the cutting load), the target load can be obtained by obtaining the relationship between the speed and the load in advance. Can be set.

On the other hand, in step 140, it is determined whether or not the cutting is finished. If an affirmative determination is made here, the process proceeds to step 150. If a negative determination is made, the process returns to step 110.
Note that whether or not the cutting has been completed is, for example, whether or not the cutting blade has reached a target position (a position where the cutting blade contacts the inner die 23), or whether or not the load has increased rapidly due to the contact with the inner die 23. It can be determined by

In step 150, since the cutting is completed, a process for returning the cutting blade 25 to the original position is performed, and this process is temporarily terminated.
Since the cutting load with which the deformation amount of the ceramic molded body 9 (that is, the deviation from the target outer diameter) is 0.5 mm or less is about 130 gf or less, the cutting blade is set so as to have this cutting load. Control the speed of 25. The amount of deformation is the amount of deformation at the end face on the rear end side in the longitudinal direction of the ceramic molded body 9 as will be described later.
<Drying process>
Next, as shown in FIG. 6, the ceramic molded body 9 is pushed out to the conveyor 13 side (arrow B direction) by the moving mechanism 39 and transferred onto the conveyor 13 (accordingly to the rotary drying device 16). Is placed on the rotating roller 51 and dried while being transferred.

Hereinafter, a drying process for performing drying using the rotary drying device 16 will be described in order.
First, as shown in FIGS. 8A and 8B, the ceramic molded body 9 is placed on the pair of rotating rollers 51 with the long direction aligned. At this time, it arrange | positions so that the rear end side of the ceramic molded body 9 may turn into the air blower 15 side (namely, nozzle 57 side).

  Next, the ceramic molded body 9 is rotated by rotating the rotating roller 51. For example, as shown in FIG. 8C, the ceramic molded body 9 is rotated in the direction of arrow E by rotating the rotating roller 51 in the direction of arrow D. In this stage, drying is performed by natural drying without blowing air.

When drying by natural drying, the rotary drying device 16 is preferably in a state separated from the surroundings, that is, in a state of drying in, for example, an airtight container.
And when it becomes a predetermined timing after rotation starts, the ventilation by the air blower 53 is started, and air is blown from the nozzle 57 toward the front end side from the rear end side of the ceramic molded body 9 to be dried. In addition, as a wind speed in the case of ventilation, 0.5 m / s or more is employable, for example.

  Specifically, as shown in FIG. 2, the ceramic molded body 9 is dried by moving the ceramic molded body 9 to the position where the nozzle 57 is disposed by the conveyor 13 and blowing air from the nozzle 57. .

  Here, as a timing for starting the blowing, it is preferable that the roundness ratio on the tip side of the ceramic molded body 9 becomes a predetermined value (for example, 70% or less). For example, the speed at which the ceramic molded body 9 is moved according to the position of the nozzle 57 is adjusted to match this timing.

  Then, when the ceramic molded body 9 has been dried to such an extent that it can be handled, the ceramic molded body 9 is taken out of the conveyor 13. In addition, the handling timing can employ | adopt the dry timing to such an extent that it does not break or break even if the ceramic molded body 9 is lifted. Alternatively, a drying time (completely drying time: hereinafter sometimes referred to as a complete drying time) that does not deform even when the ceramic molded body 9 is lifted is obtained by experiments and the like, and this complete drying time is obtained. The structure of the rotary drying device 16 (for example, the length of the conveyor 13) is designed so as to be discharged in some cases.

Moreover, after the drying described above, warm air may be blown to further promote drying.
<Measurement process>
Next, the measurement process for measuring the outer diameter of the ceramic molded body 9 will be described.

During the drying described above, the outer diameter of the ceramic molded body 9 is measured by the following method.
Here, as shown in FIG. 8C, for example, laser distance measuring devices 61a and 61b (61) are arranged above and below the ceramic molded body 9 (that is, above and below the center of the axis). .

  In order to measure the outer diameter of the ceramic molded body 9 on the front end side, the laser distance measuring device 61 is arranged to measure the outer diameter at a measurement position near the rear end, for example, 100 mm from the front end.

  And immediately after producing the ceramic molded body 9 by cutting (within 10 seconds after cutting) and after drying for a certain time, each distance from the upper and lower laser distance measuring devices 61 to the surface of the ceramic molded body 9 is set to 0.1 second. Measure multiple times each time. That is, 60 measurements are made per rotation.

Here, the “certain time” is the time from when the ceramic molded body 9 is rotated to when the blowing is started.
Thus, a plurality of outer diameters at the measurement position of the rotating ceramic molded body 9 can be obtained in a non-contact manner. Here, among the plurality of outer diameters obtained in one rotation, the largest one is the major axis and the smallest one is the minor axis.

Therefore, the roundness can be calculated from the above equation (1) using the above-described calculated values (major axis, minor axis).
<Post process>
After drying, the completely dried ceramic molded body 9 is fired to obtain a ceramic tube (for example, an alumina tube) which is a ceramic support.
[1-3. effect]
Next, effects of the first embodiment will be described.

  (1) In the first embodiment, the ceramic molded body 9 of 1.5 m or more is disposed on the rotating roller 51 and dried while rotating. And in the case of this drying, it blows and dries from the rear end side (root side) in the extrusion direction of the ceramic molded body 9 toward the front end side.

  The front end side of the ceramic molded body 9 has elapsed since being pushed out, and is gradually crushed by its own weight. Therefore, it takes time to restore the perfect circular shape by rotating the ceramic molded body 9.

On the other hand, the rear end side of the ceramic molded body 9 is immediately after being extruded and substantially maintains its shape. That is, the rear end side of the ceramic molded body 9 has a high degree of perfect circle.
Therefore, in the first embodiment, air is blown from the rear end side to the front end side of the ceramic molded body 9 while rotating the ceramic molded body 9. Thereby, while it is possible to dry from the rear end side where the degree of the perfect circle is high, the tip side can be dried after increasing the degree of recovery, and the ceramic molded body 9 having a high degree of perfect circle efficiently. Can be obtained.

  In addition, since the moisture volatilized from the material (that is, clay) of the ceramic molded body 9 is sent to the front end side by blowing, the atmosphere on the front end side changes (that is, the humidity is high). Become). Therefore, also from this point, since the flexibility of the material on the tip side can be maintained for a long time, the degree of recovery can be increased by rotating during this period.

  Thus, in the first embodiment, there is a remarkable effect that the ceramic molded body 9 can be quickly dried while ensuring the degree of recovery of the cross-sectional shape. This also has the advantage that the work of processing the ceramic molded body 9 while rotating it becomes easy and the manufacturing apparatus 1 can be made compact.

  In addition, by shortening the drying time, components of the rotating roller 51 such as iron are less likely to adhere to the ceramic molded body 9. Therefore, it is possible to suppress a decrease in performance of the ceramic molded body 9 due to the adhered substance. For example, when the ceramic molded body 9 is fired to form a sintered body and then a film is formed on the surface, the film can be suitably formed on the surface of the sintered body.

Further, according to the first embodiment, for example, a support for a fuel cell having a cut end portion that is less crushed can be mass-produced.
(2) Moreover, in this 1st Embodiment, after rotating the ceramic molded body 9, it can dry quickly, implement | achieving high recovery | restoration of a cross-sectional shape by starting ventilation by the predetermined | prescribed appropriate timing. .

  (3) Furthermore, in the first embodiment, when cutting the extrusion molded body 3, the cutting load is controlled by changing the speed of the cutting blade 25, so the deformation amount of the ceramic molded body 9 is reduced. be able to.

  The amount of deformation is the amount of deformation on the rear end side of the cut ceramic molded body 9, but the front end side of the extruded molded body 3 left on the molding die 19 side after cutting is similarly deformed. The distal end side of the ceramic molded body 9 from which the extruded molded body 3 has been cut is also deformed. Therefore, as a result, there is an effect that the deformation of the ceramic molded body 9 on the front end side can also be suppressed.

  (4) In addition, in the first embodiment, the molding die 19 has an outer die 21 and an inner die 23 that protrudes from the tip of the outer die 21 in the extrusion direction. The cutting blade 25 is moved from the outer peripheral side of the inner die 23 toward the inner die 23 to cut the extruded product 3.

  That is, when the cutting blade 25 is pushed into the extruded body 3, the inner die 23 is provided so as to support the extruded body 3 from the inside in the direction in which the cutting blade 25 is pushed. The body 3 is not deformed inward (axial center side) from the inner die 23. As a result, deformation of the extruded molded body 3 during cutting (and hence deformation of the ceramic molded body 9 after cutting) is suppressed.

Further, since the deformation of the ceramic molded body 9 is suppressed at the time of cutting, it is possible to reduce work such as cutting the deformed portion of the end portion again after drying / curing the ceramic molded body 9 and to reduce material loss and the like. There is.
[1-4. Correspondence with Claims]
Here, the correspondence of the wordings between the first embodiment and the claims will be described.

The ceramic molded body 9, the extrusion molded body 3, the rotating roller 51, the cutting blade 25, the molding die 19, the outer die 21, the inner die 23, the manufacturing apparatus 1, the extrusion molding machine 5, and the blower 15 of the first embodiment. Respectively correspond to an example of a ceramic molded body, an extruded molded body, a rotating roller, a cutting blade, a molding die, an outer die, an inner die, a manufacturing apparatus, an extrusion molding machine, and a blower of the present invention.
[2. Second Embodiment]
Next, the second embodiment will be described, but the description of the same content as the first embodiment will be omitted. In addition, about the number of each structure, the same number is used for the same thing as the said 1st Embodiment.

As shown in FIG. 9, in the second embodiment, three cutting blades 71 (71a, 71b, 71c) are used.
The planar shape of each cutting blade 71 is a shape that surrounds the periphery of the inner die 23 at an angle of 120 degrees when viewed from the front end side in the extrusion direction when the three cutting blades 71 are in contact with the inner die 23. It is said that.

Specifically, on the cutting side of each cutting blade 71, a cutting edge 73 that is curved corresponding to the outer shape of the inner die 23 (that is, along the outer periphery of the inner die 23) is formed.
Therefore, when cutting the extrusion-molded body 3, the extrusion-molded body 3 can be suitably cut by moving the respective cutting blades 71 to the axial center O side of the inner die 23 in the same manner.
[3. Third Embodiment]
Next, a third embodiment will be described, but a description of the same contents as those of the second embodiment will be omitted.

As shown in FIG. 10, in the third embodiment, four cutting blades 81 (81a, 81b, 81c, 81d) are used.
The planar shape of each cutting blade 81 is a shape that surrounds the periphery of the inner die 23 at an angle of 90 degrees when viewed from the front end side in the extrusion direction when the four cutting blades 81 are in contact with the inner die 23. It is said that.

Specifically, on the cutting side of each cutting blade 81, a cutting edge 83 that is curved corresponding to the outer shape of the inner die 23 (that is, along the outer periphery of the inner die 23) is formed.
Therefore, when cutting the extrusion-molded body 3, the extrusion-molded body 3 can be suitably cut by moving the respective cutting blades 81 to the axial center O side of the inner die 23 in the same manner.
[4. Experimental example]
Next, experimental examples conducted for confirming the effects of the present invention will be described.

<Experimental example 1>
In Experimental Example 1, the method of manufacturing the ceramic molded body of the first embodiment is used, and the ceramic of the inventive example used in the experiment with the following materials and the conditions shown in Table 1 (air blowing direction, wind speed). Samples of the molded bodies (Sample Nos. 2 to 5, 8, and 9) were produced.

And the roundness ratio at the start of air blowing (A), time until complete drying (complete drying time), final roundness ratio (B) (roundness ratio when completely dried: perfect circle when fully dry Rate).
In addition, samples of comparative examples (samples Nos. 1, 6, and 7) used in the experiment were prepared in the same manner as in the above-described invention examples except for the conditions shown in Table 1 below, and the characteristics were similarly examined. .

This will be specifically described below.
As a sample clay material used in the experiment, 10 to 50 wt% (for example, 30 wt%) of methylcellulose-based resin powder and 10 wt% of pure water with respect to 100 wt% of zirconia powder and 10 wt% of pure water are used. A clay was prepared by kneading a mixture of ˜25 wt% (for example, 15 wt%) with a kneader.

  This clay was extruded and cut in the same manner as in the first embodiment to produce a ceramic molded body having a specified size (1500 mm). The outer diameter of the ceramic molded body is about φ25 mm on average and the inner diameter is about φ20 mm on average.

And the ceramic molded object was mounted on the conveyor of the rotary drying apparatus, and it put on the rotating roller and dried.
When the ceramic molded body was dried, the blowing direction was set and the wind speed was set under the conditions shown in Table 1 below.

  The laser distance measuring device measures the outer diameter at the measurement position on the tip side of the ceramic molded body at the start of blowing and at the time of complete drying, and the roundness (A) and final roundness at the start of blowing. (B) was obtained. Furthermore, the difference (roundness difference: AB) between the roundness rate (A) at the start of air blowing and the final roundness rate (B) was obtained. The results are also shown in Table 1 below.

  Here, air blowing was started when the roundness (A) shown in Table 1 below was reached. The complete drying time is a time when a sufficient strength for lifting the ceramic molded body is obtained, and can be confirmed by actually lifting.

  As shown in Table 1, sample No. 1 and sample No. 2, sample No. 7 and sample No. 8 were compared for roundness difference (A-B), respectively. It can be seen that the roundness difference (AB) of sample No. 2 and sample No. 8 of the present invention example is larger than that of sample No. 7.

  This roundness difference (A-B) indicates the degree of improvement in the roundness, and from the rear end side of the ceramic molded body rather than blowing from the front end side to the rear end side of the ceramic molded body. It can be seen that the roundness difference (AB) is larger when the air is blown toward the tip side. That is, it can be seen that the degree of recovery of the cross-sectional shape of the ceramic molded body can be increased by blowing air from the rear end side to the front end side of the ceramic molded body.

  Table 1 shows that when the wind speed is 0.5 m / s or more, the complete drying time is 5 hours or less, that is, the higher the wind speed, the shorter the drying time. Further, it can be seen that the final roundness ratio (B) is smaller when the roundness ratio (A) at the start of air blowing is 70% or less than when the roundness ratio exceeds 70%.

On the other hand, the sample No. 6 of the comparative example which does not blow is not preferable because the time until complete drying is as long as 24 hours and the surface is discolored due to adhesion of iron.
<Experimental example 2>
Further, as Experimental Example 2, the relationship between the load of the cutting blade and the deformation amount of the ceramic molded body caused thereby was examined.

Specifically, a plurality (18 pieces) of ceramic molded bodies were manufactured by the same method as in the first embodiment.
At this time, the load applied to the cutting blade was adjusted as shown in FIG. 11 to cut the extruded molded body, and the amount of deformation (that is, the amount of deformation on the rear end side) of the ceramic molded body obtained thereby was examined.

  The amount of deformation is a value obtained by subtracting the minimum outer diameter from the maximum outer diameter on the rear end side (root side) of the ceramic molded body. The measurement position on the rear end side was a position about 10 mm from the rear end, and the laser distance measuring device was arranged at the measurement position for measurement of the outer diameter.

  The result is shown in FIG. 11, and it can be seen that the amount of deformation increases as the load (ie, cutting load) increases. Specifically, since the cutting load at which the deformation amount is 0.5 mm or less is about 130 gf or less, it can be seen that it is preferable to control the speed of the cutting blade so as to be this cutting load.

Here, as shown in FIG. 11, the regression line of the experimental data is y = 0.0062x−0.3309, and the determination coefficient R ² is 0.9142.
In addition, it is estimated that the reason why the deformation occurs on the rear end side of the ceramic molded body despite the presence of the inner die is the retention of clay inside the die.
[5. Other Embodiments]
It goes without saying that the present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the present invention.

  (1) For example, in the first embodiment, a pair of cutting blades are arranged in the vertical direction and the extrusion-molded body is cut in the vertical direction, but a pair of cutting blades are arranged in the horizontal direction and the extrusion-molding body is oriented horizontally. It may be cut into pieces.

(2) The materials of the inner die, the outer die, and the cutting blade are not limited to the first embodiment described above, and various known materials can be used.
(3) The shape and arrangement of the conveyor, the rotating roller, and the nozzle are not limited to the above-described first embodiment, and various shapes and arrangements can be adopted within the scope of the present invention.

For example, you may mount an extrusion molding directly on a conveyor, without providing a mounting part.
(4) The configurations of the embodiments can be combined as appropriate.
(5) The present invention is not limited to a ceramic molded body that is a cylindrical support for a cylindrical horizontal stripe type solid oxide fuel cell or the like, and can be applied to other various methods of manufacturing a ceramic molded body.

  For example, the present invention can be applied to the production of a fuel cell support of another type of solid oxide form. Further, for example, the present invention can be applied to the production of long ceramic tubes such as a roller of a firing furnace, a support used for ceramic filtration, and a protective tube of a thermocouple.

DESCRIPTION OF SYMBOLS 1 ... Manufacturing apparatus 3 ... Extrusion molding 5 ... Extrusion molding machine 7 ... Cutting machine 9 ... Ceramic molding 15 ... Blower 19 ... Molding die 21 ... Outer die 23 ... Inner die 25, 71, 81 ... Cutting blade 51 ... Rotating roller

Claims (6)

A method for producing a ceramic molded body for producing a cylindrical ceramic molded body having an axial length of 1.5 m or more,
An extrusion process for producing an extruded product by extrusion;
A cutting step of cutting the extruded molded body into a predetermined length to produce a ceramic molded body,
The ceramic molded body is blown from the rear end side to the front end side in the extrusion direction of the ceramic molded body with respect to the plurality of ceramic molded bodies that rotate on a plurality of rotating rollers that can rotate and convey the ceramic molded body. A drying process to dry;
A method for producing a ceramic molded body. A method for producing a ceramic molded body according to claim 1,
The cutting step is a step of cutting the extruded product with a cutting blade,
A method for producing a ceramic molded body, wherein a cutting load is controlled by changing a speed of a cutting blade in a cutting process of the extruded molded body. A method for producing a ceramic molded body according to claim 1 or 2,
In the extrusion molding step, a molding die for molding the extrusion-molded body includes an outer die, and an inner die having a tip protruding in the extrusion direction from the tip of the outer die,
The method of manufacturing a ceramic molded body, wherein in the cutting step, a cutting blade is moved from the outer peripheral side of the inner die toward the inner die to cut the extruded molded body. A ceramic molded body manufacturing apparatus for manufacturing a cylindrical ceramic molded body having an axial length of 1.5 m or more,
An extruder for producing an extruded product by extrusion;
A cutting machine for producing a ceramic molded body by cutting the extruded molded body into a predetermined length;
A plurality of rotating rollers capable of rotating and conveying the ceramic molded body;
A blower that blows air from the rear end side in the extrusion direction of the ceramic molded body toward the front end side and dries the ceramic molded body that rotates on the rotating roller, and
An apparatus for producing a ceramic molded body. An apparatus for producing a ceramic molded body according to claim 4,
The cutting machine has a cutting blade for cutting the extrusion molded body,
An apparatus for manufacturing a ceramic molded body, comprising a mechanism for controlling a cutting load by changing a speed of a cutting blade in a cutting process of the extruded molded body. An apparatus for producing a ceramic molded body according to claim 4 or 5,
The extrusion molding machine includes a molding die in which the tip of the inner die protrudes in the extrusion direction from the tip of the outer die,
The cutting machine has a cutting blade for cutting the extruded body extruded from the molding die,
An apparatus for manufacturing a ceramic molded body, having a mechanism for moving the cutting blade from the outer peripheral side of the inner die toward the inner die to cut the extruded molded body.