JP4410863B2 - Ceramic filter sealing device and method of manufacturing ceramic filter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to the manufacture of ceramic filters used in places where solids need to be separated from gas, such as exhaust systems of diesel engines. More specifically, the present invention relates to a sealing device and a manufacturing method for a ceramic filter that can seal the end portion of a ceramic filter formed into a honeycomb shape without protruding.
[0002]
[Prior art]
This type of honeycomb-structured ceramic filter is used by closing one opening of each cell in a zigzag manner with the same sealant. For this purpose, in the process of manufacturing the ceramic filter, after forming into a honeycomb structure and drying, a sealing agent is injected into the opening to be sealed in each cell. As a result, one end of each cell is sealed in a staggered manner. When this is fired, a ceramic filter is completed.
[0003]
Here, as shown in FIG. 7, a part of the sealing agent 2 injected into the opening of the cell protrudes from the ceramic filter 1 to form a mountain-shaped surplus 3. If this is fired as it is, the dimensions of the ceramic filter 1 will be out of order by the height of the surplus 3. The height of the surplus 3 is 0.5 mm or more, which is inconvenient because it is larger than the dimensional tolerance of the ceramic filter 1. Therefore, in the prior art, as shown in FIG.
[0004]
[Problems to be solved by the invention]
However, the conventional method described above must rely on manual work. In addition, both end faces of the ceramic filter 1 must be processed one by one. This is extremely inefficient. Further, when the excess sealing agent 2 is wiped off with the sponge 99, as shown in FIG. 13, a part of the wiped sealing agent 2 may enter the neighboring cell and be blocked. If this happens, the ceramic filter 1 becomes a defective product.
[0005]
The present invention has been made for the purpose of solving the problems of the prior art described above. That is, the problem is that a sealing device and a manufacturing method for a ceramic filter that can efficiently flatten the surplus portion of the sealing agent injected into the ceramic filter and that do not block the adjacent cells with the excess sealing agent. It is to provide a method.
[0006]
[Means for Solving the Problems]
In order to solve this problem, a sealing device for ceramic filter according to the present invention (this device) includes an injection means for injecting a fluid sealing agent into an end of a ceramic filter having a honeycomb structure, and a sealing agent is injected. The ceramic filter is vibrated in the cell direction, and has an excitation means such as a ball vibrator for flattening the sealing agent that is overlaid at the end. In the method for manufacturing a ceramic filter of the present invention, a fluid sealing agent is injected into a cell to be sealed at an end of a honeycomb structure ceramic filter, and the ceramic filter into which the sealing agent has been injected is vibrated in the cell direction. The end portion of the ceramic filter is sealed by flattening the sealing agent that is overfilled at the end, and firing the ceramic filter after the sealing agent is flattened.
[0007]
That is, first, a sealing agent is injected into a cell to be sealed at the end of a ceramic filter formed into a honeycomb structure. At this point, the ceramic filter is in a molded and dried state and has not yet been fired. The sealing agent is made of the same material as the ceramic filter and is a fluid containing a large amount of solvent. In this state, as shown in FIG. 7, a part of the sealing agent injected into the opening of the cell protrudes from the ceramic filter and forms a mountain-shaped surplus. The ceramic filter in this state is held by the work holder of the apparatus and is vibrated in the cell direction by the vibration means.
[0008]
Then, the vibration of the ceramic filter is also transmitted to the sealing agent. However, since the sealant is a fluid, it moves slightly later than the ceramic filter. For this reason, the sealing agent contacts the innermost part of the inner surface of the ceramic filter cell. Since the ceramic filter is originally dried from the same material as the sealing agent, the wettability between the ceramic filter and the sealing agent is good. Due to this and the surface tension of the sealing agent, which is a fluid, the sealing agent is drawn into the cell and the end of the ceramic filter becomes flat. Thereafter, drying the sealing agent, and you fired ceramic filter (and sealing agents).
[0009]
As a result, the end of the ceramic filter can be sealed flat without protruding without relying on manual work. In addition, if a sealing agent is injected into the ends of both sides of the ceramic filter, the end faces on both sides can be sealed with a single vibration treatment, and work efficiency is high. In addition, there is no possibility that the adjacent cells are blocked by the surplus sealing agent and become defective as shown in FIG. Note that the vibration of the ceramic filter only needs to include a component in a direction parallel to the cell. Components in other directions may be included.
[0010]
Here, if the vibration frequency of the vibrating means is too small (slow vibration), the delay of the sealing agent relative to the ceramic filter is relatively small. For this reason, the effect is insufficient, the extra portion of the sealing agent cannot be drawn inward, and the end of the ceramic filter does not become flat. On the other hand, if the frequency is too high (vibration is fast), the sealing agent is excessively drawn into the inner part of the inner surface of the cell, so that the sealing agent is drawn inward more than necessary. Since the amount of sealant injected at the end of the cell is finite, in this situation there is a hole in the center of the sealant. Therefore, the frequency of vibration is preferably in the range of 160 to 210 Hz (more preferably 170 to 200 Hz, more preferably 180 to 190 Hz) so that these problems do not occur.
[0011]
In this case, it is preferable that an elastic pad member for transmitting the vibration of the vibrating means to the ceramic filter is provided so that the pad member contacts the ceramic filter. This is because the ceramic filter which is vibrated by the vibration means is not fired and cannot be said to have sufficient mechanical strength. That is, if the portion of the vibrating means or work holder that contacts the ceramic filter is a metal or other rigid member, the ceramic filter may be deformed when contacting. By providing an elastic pad member at the portion in contact with the ceramic filter, the ceramic filter can be held and excited without fear of breaking.
[0012]
Further, it is preferable to use a pad member made of natural rubber. This is because if natural rubber is used, the vibration of the vibrating means can be reliably transmitted to the ceramic filter. That is, even if it is an elastic body, if it is quite hard such as urethane rubber, the adhesion in the state of holding the ceramic filter is insufficient. A ceramic filter having a honeycomb structure may have some unevenness on the outer surface reflecting the cell structure in the drying process. For this reason, a relatively hard rubber such as urethane rubber that does not easily deform is poorly adhered to the ceramic filter. For this reason, the vibration of the vibration means cannot be reliably transmitted to the ceramic filter. On the other hand, it is not good to use something too weak. This is because if the pad member is too weak, vibrations are absorbed by the pad member and are not transmitted to the ceramic filter.
[0013]
If a pad member having a suitable hardness such as natural rubber is used, when the ceramic filter is held, the pad member is appropriately deformed corresponding to the unevenness of the outer surface. For this reason, there is sufficient adhesion when the ceramic filter is held. On the other hand, it is too weak to absorb vibrations. For this reason, the vibration of the vibration means is reliably transmitted to the ceramic filter.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below in detail with reference to the accompanying drawings. Therefore, first, the ceramic filter 1 handled in the present embodiment will be briefly described. As shown in FIG. 1, the ceramic filter 1 has an honest rectangular shape. Its total length k is about 150 mm, and one side h of the cross section is about 33 mm. The dimensional tolerance for both the total length k and the side h is about ± 0.5 mm. The ceramic filter 1 has a large number of vertical and horizontal inner walls parallel to the total length k. Thereby, the inside of the ceramic filter 1 is divided into a large number of cells parallel to the total length k.
[0015]
The ceramic filter 1 is obtained by molding a slurry obtained by kneading ceramic powder with a solvent and drying the slurry. Since there is some deformation during the drying, the side surface of the ceramic filter 1 has irregularities corresponding to the internal cell structure as shown in FIG. However, the unevenness is within the range of dimensional tolerance (FIG. 2 is exaggerated). The sealing device according to the present embodiment seals the ends of each cell in a zigzag manner before firing the ceramic filter 1.
[0016]
As shown in the plan view of FIG. 3, the sealing device 10 according to the present embodiment includes a work transport path 11 through which the dried ceramic filter 1 is transported, and a ceramic that is a work on the work transport path 11. It has injection devices 12 and 12 for injecting a sealant into the filter 1 and a vibration part 13 for vibrating the ceramic filter 1 after the injection. That is, the ceramic filter 1 is received in the work conveyance path 11 and is poured downward in FIG. 3, while a sealing agent is injected into the end by the injection devices 12 and 12, and the end is flattened by the vibration unit 13. It is to become.
[0017]
As shown in the front view of FIG. 4, the excitation unit 13 is provided with a ball vibrator 15 that is a vibration drive source. The ball vibrator 15 incorporates a cylindrical drum, and has a spherical ball therein. The ball is rotated in the drum by blowing compressed air into the drum, and vibration is generated by the reaction of the rotation. The degree of vibration (frequency, etc.) can be adjusted by the pressure of the compressed air. The ball vibrator 15 is attached to the pillar 16 in such a manner that the vibration includes a component in a direction parallel to the cell of the ceramic filter 1 and can be moved up and down on the pillar 16. A wire rope vibration isolator 17 is provided between the ball vibrator 15 and the pillar 16 so that the vibration of the ball vibrator 15 is not transmitted to the pillar 16.
[0018]
A vibration plate 18 for transmitting vibration to the ceramic filter 1 is attached to the lower portion of the ball vibrator 15. As shown in FIG. 5, two rubber pads 19 made of natural rubber are attached to the lower surface of the vibration plate 18. Each rubber pad 19 is a plate-like member having a thickness of 3 mm, a width of 33 mm (the same as one side h of the cross section of the ceramic filter 1), and a length of 30 mm. The rubber pads 19 are members that directly contact the ceramic filter 1. The vibration of the ball vibrator 15 is transmitted from the vibration plate 18 to the ceramic filter 1 through the rubber pads 19 and 19. Each rubber pad 19 is disposed so as to be positioned at both ends of the ceramic filter 1.
[0019]
Returning to FIG. 4, chucks 20, 20 for holding the ceramic filter 1 are provided on both sides below the ball vibrator 15. As shown in FIG. 6, each chuck 20 has a pair of claws 21 and 21 that move in parallel to open and close. Further, urethane chuck rubbers 22 and 22 are attached to the inner surfaces of the claws 21 and 21. Thereby, the unfired ceramic filter 1 can be held without breaking.
[0020]
The sealing device 10 seals the ceramic filter 1 by the following method. First, the sealing agent is injected by the injection devices 12 and 12 into the molded and dried ceramic filter 1 flowing down the workpiece conveyance path 11 in FIG. The sealing agent to be injected is a slurry obtained by kneading ceramic powder of the same material as the ceramic filter 1 with a solvent. However, compared with the slurry for forming the ceramic filter 1, it contains a large amount of solvent and is a fluid. The sealing agent is injected into one end of each cell of the ceramic filter 1. And the edge part into which sealing agent is inject | poured is an other side in the mutually adjacent cells. This state is shown in FIG. In this state, a part of the sealing agent 2 injected into the opening of the cell protrudes from the ceramic filter 1 to form a mountain-shaped surplus 3.
[0021]
Vibration is applied to the ceramic filter 1 in this state by the vibration unit 13. For this reason, the ceramic filter 1 is held by the chucks 20 and 20. At the time of holding, the member on the side of the chucks 20 and 20 that directly contacts the ceramic filter 1 is the urethane chuck rubber 22 described in FIG. For this reason, the ceramic filter 1 is not destroyed.
[0022]
Then, the ball vibrator 15 descends and comes into contact with the ceramic filter 1 held by the chucks 20 and 20 (see FIG. 4). At this time, the member on the ball vibrator 15 side that directly contacts the ceramic filter 1 is the rubber pad 19 made of natural rubber described in FIG. For this reason, the ceramic filter 1 is not destroyed. In addition, because of the flexibility of natural rubber, the rubber pad 19 contracts according to the unevenness (see FIG. 2) of the side surface of the ceramic filter 1, and the ceramic filter 1 and the rubber pad 19 come into close contact as shown in FIG. If the rubber pad 19 is not provided, or if it is provided, it is made of a relatively hard material such as urethane, a gap may be formed due to the unevenness on the side surface of the ceramic filter 1, or otherwise. In this case, the ceramic filter 1 is destroyed.
[0023]
In this state, the ball vibrator 15 is driven to vibrate. Then, the vibration plate 18 also vibrates together with the ball vibrator 15. Further, the vibration is transmitted to the ceramic filter 1 through the rubber pad 19. At this time, since the ceramic filter 1 and the rubber pad 19 are in close contact with each other, the transmission of vibration to the ceramic filter 1 is reliable. If there is a gap between the ceramic filter 1 and the vibration plate 18, reliable vibration transmission is not possible.
[0024]
For this reason, the ceramic filter 1 also vibrates. The vibration includes a component parallel to the cell direction. Due to this vibration, the phenomenon shown in FIG. 9 occurs in the sealing agent 2 injected into the end of each cell. That is, since the sealing agent 2 is a fluid, its movement is delayed from the movement of the ceramic filter 1. Therefore, immediately after the ceramic filter 1 moves leftward in FIG. 9, the state shown in FIG. 9B is obtained. FIG. 9A shows a state before starting vibration.
[0025]
In the state of (b), although the ceramic filter 1 has moved to the left but the sealing agent 2 has not yet moved, the sealing agent 2 has entered a little from the inside of the ceramic filter 1. Then, since the sealing agent 2 is made of the same material as the ceramic filter 1 and the wettability of both is good, the sealing agent 2 comes into contact with the deeper part of the wall surface of the ceramic filter 1 ((c) of FIG. 9). Thereafter, when the ceramic filter 1 moves rightward this time, the state of FIG. In this state, both the left and right surfaces of the sealing agent 2 are curved surfaces. For this reason, strong surface tension works and the sealing agent 2 moves to the right side. That is, it is drawn into the inside of the ceramic filter 1 to be in the state of FIG. Thus, surplus 3 disappears. Since this phenomenon occurs at both ends of the ceramic filter 1, the ends of the ceramic filter 1 are flattened as shown in FIG.
[0026]
The chuck rubber 22 is interposed between the ceramic filter 1 and the chuck 20 as described above. For this reason, the vibration of the ceramic filter 1 is not transmitted to the chuck 20. Therefore, the chuck 20 together with the ceramic filter 1 does not vibrate and no extra load is applied to the chuck 20.
[0027]
The frequency of this vibration should not be too small or too large. If the frequency is too small (slow vibration), the effect is insufficient and the end of the ceramic filter 1 does not become flat. If the frequency is too large (vibration is fast), the effect is excessive, and the sealing agent 2 is drawn inward more than necessary, and a hole is formed in the center of the sealing agent 2 as shown in FIG. Considering these, the preferable range of the vibration frequency is 160 to 210 Hz (more preferably 170 to 200 Hz, and still more preferably 180 to 190 Hz). The amplitude of the vibration is suitably about 1 to 2 mm, which is slightly larger than the height of the surplus 3. The vibration time is suitably about 5 to 20 seconds.
[0028]
For example, in the case of using a pneumatic ball vibrator UH13 manufactured by EXEN as the ball vibrator 15, a preferable frequency of about 187 Hz can be obtained by operating at an air pressure of ² kgf / cm ² . However, when operating at an air pressure of 3 kgf / cm ² , the frequency becomes about 230 Hz, which is excessive. Moreover, when operating at an air pressure of 1.5 kgf / cm ² , only a frequency of about 150 Hz can be obtained, which is insufficient. Therefore, when this type of ball vibrator 15 is used, it is preferable to operate at an air pressure of about ² kgf / cm ² .
[0029]
In this way, the end portions on both sides of the ceramic filter 1 are flattened. Thereafter, after the sealing agent 2 is dried, the entire ceramic filter 1 (including the sealing agent 2 at this time) may be fired.
[0030]
As described in detail above, in the sealing device 10 according to the present embodiment, the vibration of the ball vibrator 15 is applied to the ceramic filter 1 that has been injected with the sealing agent 2 by the injection devices 12, 12. By doing so, the portion of the surplus 3 of the sealing agent 2 is drawn inward. For this reason, it is possible to seal the cells in a zigzag manner in a state in which the end portions of the respective cells of the ceramic filter 1 are flattened without manual work. Therefore, the sealing process of the ceramic filter 1 can be performed efficiently. In addition, the neighboring cells are not blocked, and it is difficult for defective products to occur.
[0031]
Here, a rubber pad 19 made of natural rubber is attached to the vibration plate 18 below the ball vibrator 15, and the rubber pad 19 is brought into contact with the ceramic filter 1. Therefore, the dried and unfired ceramic filter 1 is brought into close contact with it without breaking, and the vibration of the ball vibrator 15 is reliably transmitted. Further, a chuck rubber 22 is provided on the chuck 20 that holds the ceramic filter 1 to be applied with vibration, and the ceramic filter 1 is held by the chuck rubber 22. For this reason, the ceramic filter 1 can be held without being destroyed. Further, the vibration of the ceramic filter 1 is not transmitted to the chuck 20.
[0032]
In addition, the said embodiment is only a mere illustration and does not limit this invention at all. Therefore, the present invention can naturally be improved and modified in various ways without departing from the gist thereof. For example, instead of the ball vibrator 15 which is the vibration means, another type of vibration generator may be used.
[0033]
【The invention's effect】
As is apparent from the above description, according to the present invention, the surplus portion of the sealing agent injected into the ceramic filter can be efficiently flattened and the surplus sealing agent does not block the adjacent cells. A filter sealing device and a manufacturing method are provided.
[Brief description of the drawings]
FIG. 1 is an overall view of a ceramic filter.
FIG. 2 is a diagram showing irregularities on the side surface of a ceramic filter.
FIG. 3 is a plan view showing a schematic configuration of the sealing device according to the embodiment.
FIG. 4 is a front view showing a schematic configuration of the sealing device according to the embodiment.
FIG. 5 is a diagram illustrating a rubber pad between a ball vibrator and a ceramic filter.
FIG. 6 is a diagram illustrating a chuck that holds a ceramic filter.
FIG. 7 is a view showing a state immediately after a sealing agent is injected into a ceramic filter.
FIG. 8 is a diagram showing a state in which a flexible rubber pad is in close contact with a ceramic filter.
FIG. 9 is a diagram showing a state in which the sealing agent is drawn into the ceramic filter by vibration.
FIG. 10 is a diagram showing a ceramic filter in a state in which an end portion is flattened.
FIG. 11 is a view showing a state in which a hole is formed in the sealing agent.
FIG. 12 is a view showing a conventional example in which an excess of a sealing agent is removed by wiping with a sponge.
FIG. 13 is a diagram showing a state in which cells are blocked by a part of the excess sealing agent wiped off.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Ceramic filter 10 Sealing apparatus 15 Ball vibrator 19 Rubber pad 20 Chuck

Claims (10)

Injection means for injecting a fluid sealing agent into the end of the honeycomb structure ceramic filter;
A ceramic filter comprising a vibrating means for vibrating the ceramic filter in which the sealing agent is injected by the injection means in the cell direction and flattening the sealing agent that is overlaid at the end. Sealing device. The sealing device for a ceramic filter according to claim 1,
A sealing device for a ceramic filter, wherein the vibration frequency of the vibrating means is in a range of 160 to 210 Hz. In the sealing device of the ceramic filter of Claim 1 or Claim 2,
A sealing device for a ceramic filter, comprising an elastic pad member for transmitting the vibration of the vibrating means to the ceramic filter. The sealing device for a ceramic filter according to claim 3,
A sealing device for a ceramic filter, wherein the pad member is made of natural rubber. In the sealing device of the ceramic filter as described in any one of Claim 1- Claim 4,
A sealing device for a ceramic filter, wherein the vibration means is a ball vibrator. In a manufacturing method of a ceramic filter formed by sealing an end of a ceramic filter having a honeycomb structure,
Injecting a fluid sealant into the cell to be sealed at the end of the ceramic filter;
The ceramic filter into which the sealing agent is injected is vibrated in the cell direction to flatten the sealing agent that is overfilled at the end (step 1),
A method for producing a ceramic filter, comprising firing the ceramic filter after the sealing agent has been flattened . In the manufacturing method of the ceramic filter of Claim 6,
The method for producing a ceramic filter, wherein the vibration frequency in the step 1 is in a range of 160 to 210 Hz. In the manufacturing method of the ceramic filter of Claim 6 or Claim 7,
In the step 1, vibration is transmitted to the ceramic filter through an elastic pad member. In the manufacturing method of the ceramic filter of Claim 8,
A method for producing a ceramic filter, wherein the pad member is made of natural rubber. In the manufacturing method of the ceramic filter as described in any one of Claim 6- Claim 9,
A method of manufacturing a ceramic filter, wherein the vibration in the step 1 is performed by a ball vibrator.

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