JP2007016812A - Joint sheet gasket - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint sheet gasket capable of keeping excellent airtightness without being affected by troubles of an adhesive such as application quantity of the adhesive, contraction of the adhesive, and also having excellent fitting workability. <P>SOLUTION: Ends 12a and 12b of a plurality of annular split body 12 formed by punching a plate-like gasket material is assembled with each other to form a joint sheet gasket 10. One end 12a and the other end 12b in the annular split body 12 are formed as a dovetail groove 20 in an almost mutually complementary shape. Each projection end surface containing the dovetail groove is formed to have inclination angles α and β obliquely toward the thickness direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a joint sheet gasket.

  For example, when manufacturing a large-diameter joint sheet gasket that is difficult to create by punching from a single sheet, first, form a plurality of annular segments, and then combine the ends of these segments. By doing so, a joint sheet gasket of a desired size is created.

  Here, as shown in FIG. 5 (A), the shape of the joining end portion of the annular divided body to be combined includes the combination of the end portions 2a and 4a formed at right angles to each other, as well as the same figure (B). As shown in FIG. 2, a butt end face having a tapered surface 6 or a joint portion having a groove 8 as shown in FIG. ).

In general, an appropriate adhesive is interposed in these joint portions.
However, in the case shown in FIG. 5 (A) or FIG. 5 (C), even if tightened in the thickness direction for sealing, a strong compressive force is not applied between the end faces of the joint, so that sufficient sealing performance is obtained. There is no familiarity that can be obtained. In addition, when applying an adhesive to bond between both members, the applied adhesive shrinks after curing, or a predetermined amount of adhesive is not applied at the time of application, resulting in poor adhesion, and long-term use When the adhesive deteriorates due to the above, a minute gap is generated in the thickness direction of the butt end face, and leakage easily occurs from this gap during sealing. In fact, it is generally recognized that joint sheet gaskets made from a split body are inferior in terms of room temperature and airtightness when compared to an integral joint sheet gasket that has not been created by joining. There is a problem in getting.

  That is, in the prior art, as shown in FIG. 5 (C), with the dovetail 8, one annular segment 2 is fitted over the other annular segment 4 as shown in FIG. 6. However, at the time of this fitting, as shown in FIG. 6, a clearance S was secured between the lower end 2 b of the upper annular divided body 2 and the upper end 4 b of the lower annular divided body 4. It will fit in the state. This gap S maintains the same dimensions after being fitted. If the clearance S is set to be small in advance, the annular divided bodies 2 and 4 are closely joined to each other, so that the sealing performance as a gasket is good, but the working efficiency at the time of fitting is remarkably lowered, and the fitting work is performed. There is a risk of causing loss and damage.

On the other hand, if the gap S is set large in advance, the workability of joining the annular divided bodies 2 and 4 is good, but the sealing performance as a gasket is remarkably lowered and the function of the gasket is not achieved.
Japanese Patent No. 3118588

  By the way, among FIGS. 5 (A), (B), and (C), the most frequently used method is a fitting method provided with the dovetail groove 8 shown in FIG. 5 (C). When the two annular divided bodies 2 and 4 are assembled to each other by this fitting method, the dimensional accuracy between the assembled members 2 and 4 is quite important. If the gap S for assembling both the members 2 and 4 is widened, leakage from the joint portion increases, which causes a problem in terms of sealing performance. Further, if the gap S between the two members is too narrow, it is difficult to fit the two members, resulting in an increase in production cost.

Therefore, nowadays, it is eager to provide a new joining method for a joint sheet gasket having a particularly large diameter.
In view of such a conventional situation, the present invention can maintain high airtightness without being affected at all by problems of the adhesive such as the amount of adhesive applied, shrinkage of the adhesive, and the fitting workability. It also aims to provide a good joint sheet gasket.

The joint sheet gasket according to the present invention is:
A joint sheet gasket configured by assembling together ends of a plurality of annular divided bodies formed by punching plate-shaped gasket material,
While forming one end and the other end of the annular divided body as a dovetail groove having a shape substantially complementary to each other,
Each butt end face including these dovetail grooves is characterized in that the end face of at least one divided body is formed to be inclined obliquely in the thickness direction.

  According to the present invention having such a configuration, the butt area of the joint portion is widened, and when tightened from both sides with a bolt or the like, conformability is imparted between the joint end surfaces, and sufficient sealing performance can be exhibited. Further, it is possible to prevent slipping by a dovetail groove. Accordingly, the adhesion can be maintained without depending on the adhesive, and in some cases, the use of the adhesive can be omitted.

Here, in the case where both the divided bodies of the butt end surfaces are formed to be inclined obliquely, the inclination angles directed to the thickness direction are preferably in the range of 45 ° to 85 °, respectively.
If the inclination angle is set in such a range, an excessive compressive force acts on the joint portion and partial damage does not occur, and sufficient sealing performance can be exhibited.

In the present invention, it is preferable that a phase difference is provided in advance in the inclination angle so that the butt end faces of the annular divided body wrap in a state before tightening.
If such a phase difference is provided, even if the density of the fitting portion increases when compressed and a gap is generated between both members, the gap can be eliminated.

Furthermore, in the present invention, the phase difference is preferably in the range of 5 ° to 25 °.
If the phase difference in such a range is provided, the density of the overlapping portion will not be excessively increased in hardness and will not be damaged.

In addition, when the split body on only one side of the butt end face is inclined obliquely and the other is formed at a right angle, the inclination angle on the obliquely inclined side is preferably in the range of 65 ° to 85 °.
Even with such a configuration, substantially the same operational effects as described above can be obtained.

According to the joint sheet gasket according to the present invention, when tightened, the two can be reliably brought into close contact with each other, and the dovetail groove can be used to prevent the joint sheet gasket from coming off.
Moreover, if the inclined surfaces which wrap around each other are provided, the density of the portion is improved, so that the sealing performance can be further improved.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows an embodiment of a joint sheet gasket according to the present invention.
This joint sheet gasket 10 is composed of a large-diameter divided body, and is formed by preparing four annular divided bodies 12 having the same shape and fitting the ends of each. That is, one end portion (front end portion) 12a and the other end portion (rear end portion) 12b of one annular divided body 12 are formed in substantially complementary shapes. Then, by combining these end portions, a substantially trapezoidal dovetail groove 20 is formed. The shape of the dovetail groove 20 is not limited to the shape of the embodiment, and may be, for example, a shape close to a substantially semicircular shape. Further, in this embodiment, no adhesive is applied to the fitting portion of the divided body, but an adhesive can also be interposed.

  On the other hand, the cross-sectional shapes of both end portions 12a and 12b of the annular divided body 12 according to this embodiment are not cut at right angles in the thickness direction. That is, as shown in FIG. 2, it is formed to have an inclination angle α. When the processing for obtaining the inclined surface is referred to as edge processing, the inclination angle α in the natural state of edge processing is set in the following range.

  That is, as shown in FIG. 3, the thickness t of the annular divided body 12 used in the large-diameter joint sheet gasket 10 is in the range of 0.5 to 5 mm. On the other hand, the edge width u of the annular divided body 12 is 0.5 mm or more. The inclination angle α is set under such conditions. A preferable inclination angle α is in a range of 45 ° to 85 °.

  If the inclination angle α is set in such a range, both high airtightness and fitting workability can be achieved. In addition, when the range of the inclination angle α is less than this, the edge portion tends to be an acute angle, and is easily damaged when performing the joining process. On the other hand, if the inclination angle α is greater than this, the effect of edge processing cannot be expected sufficiently.

  That is, as shown in FIG. 3, when edge processing is applied to both end portions 12 a and 12 b of the annular divided bodies 12 and 12, the upper annular divided body 12 is fitted to the lower annular divided body 12. Both end portions 12a and 12b always come into contact during fitting. Moreover, once contacted, they are guided to each other along the inclined surface with the inclination angle α, so that the gap S that has been initially generated is eliminated when the assembly is completed. In addition, when the joint surface has an inclination angle α, if the joint sheet gasket 10 shown in FIG. 1 is tightened for sealing, the conformability between the joint surfaces is improved and the degree of adhesion is improved.

  In general, the annular divided body 12 is formed by punching with a Thomson type or an iron type, but it is impossible to form the inclination angle α only by these punching processes. Therefore, first, it is only necessary to perform punching perpendicular to the gasket surface with a Thomson type or the like, and then form a necessary inclination with a cutter knife or a grinder. However, the formation of the inclination angle α is not limited to this.

  As mentioned above, although the joint sheet gasket by one Example of this invention was demonstrated, this invention can be variously deformed. For example, the uneven shape of the dovetail is not limited to the shape of the above embodiment.

  Further, the shape of the joint sheet gasket 10 is not limited to an annular shape, and may be a rectangular shape, that is, a frame shape. Further, the present invention is particularly suitable for a large-diameter joint sheet gasket containing graphite, but is not limited to materials and calibers.

  Moreover, in the said Example, although the inclination angle (alpha) of the one edge part 12a and the other edge part 12b of the cyclic | annular division body 12 is both set to the same angle, it replaces with this, and it overlaps partially. A phase difference may be provided in the inclination angle.

FIG. 4 shows another embodiment of the present invention in which a phase difference is provided so as to partially wrap.
In this embodiment, the inclination angle α of one end 12a and the inclination angle β of the other end 12b are different from each other and a phase difference is provided. Under such conditions, when the upper annular divided body 12 is assembled to the lower annular divided body 12, a portion 16 that wraps around the combined end face is generated, and the density of the portion 16 increases. Therefore, the sealing performance of the combined part of the divided bodies is improved. Such a phase difference (α−β) or (β−α) is desirably in the range of 5 ° to 25 °. If the phase difference in such a range is provided, they can be combined with each other without deformation, and no deformation or the like occurs during the combination.

  Moreover, in the said Example, although the inclination | tilt angle (alpha) is each provided in the butt | matching surface of both the cyclic | annular division bodies 12 and 12 mutually attached, the butt | matching surface of one cyclic | annular division body 12 shall be a right angle, It is also possible to provide the inclination angle α only on the butt end face of the other annular divided body 12.

  When the inclination angle is provided only on one side, the inclination angle α is in the range of 65 ° to 85 °. As described above, when edge processing is performed only on one side, the workability can be simplified even though the sealing performance may be slightly inferior to the case where edge processing is provided on both sides.

  In order to investigate the effect of the present invention, a joint sheet gasket actually composed of a plurality of annular divided bodies 12 was created, and the joint processability (workability at the time of combination) and sealability of the joint sheet were investigated. .

Hereinafter, experimental results of the present invention will be described.
First, Experiment 1 was performed in order to investigate the joining workability and the sealing performance when the inclination angles α and β were the same. The results of Experiment 1 are shown in Table 1. In Experiment 1, no adhesive was used.

  Further, a phase difference was provided between the inclination angles α and β, and Experiment 2 was performed in order to examine how the phase difference differs in joining workability and sealing performance. The results of Experiment 2 are shown in Table 2. In Experiment 2, a sheet having a thickness t of 3.0 mm was used, and a rubber-based adhesive was applied to the bonded cross section, and then fitted. Further, in Experiment 1 and Experiment 2, a dovetail groove 20 as shown in FIG. 1 is formed between one end 12a and the other end 12b.

In Table 1, the inclination angles α of Examples 1, 2, and 3 were set to 72 °, 45 °, and 81 °. In each of Comparative Examples 1, 2, and 3, the inclination angle α is 90 °.
The gap S between the end portions before fitting was set to 1.0 mm, 3.0 mm, and 0.5 mm in Examples 1, 2, and 3, respectively. Thus, in Examples 1, 2, and 3, the gap S was changed, but after fitting, all the gaps became 0.0 mm. Further, the bonding processability and sealing performance of Examples 1, 2, and 3 were examined, but all of these were good and could be fitted without any problem.

  On the other hand, in Comparative Examples 1, 2, and 3, the clearance S before fitting was set to 0.0 mm, 0.5 mm, and 1.0 mm. These gaps did not change after fitting. Further, in Comparative Examples 1, 2, and 3, in the case of Comparative Example 1 in which the gap S before fitting is 0.0 mm, there is a problem in joining workability, and there is a possibility that the work may be damaged if work is not performed with care.

  Moreover, in the case of the comparative example 2 with a clearance of 0.5 mm and the comparative example 3 with a clearance of 1.0 mm, a problem arises in the sealing performance. In particular, in the comparative example 3, the internal pressure can hardly be sealed. It was.

Next, the results of Experiment 2 will be described with reference to Table 2.
In Experiment 2, as in Example 1 used in Experiment 1, a sample having both inclination angles α and β of 72 ° was prepared as a reference, and Example 1 was used.

  Further, as Examples 4, 5, 6, and 7 of Experiment 2, the inclination angle α (left member edge angle) and the inclination angle β (right member edge angle) were set as shown in Table 2.

  As can be seen from Table 2, in Examples 4 to 7 in which a phase difference is provided between α and β, the bonding processability and sealability are both good, and no defects are generated, especially in comparison with the comparative example. Sufficient sealing performance was confirmed. Moreover, even if it contrasted with Example 1 with the same inclination | tilt angle (alpha) at 72 degrees, the direction of Examples 4-7 was favorable.

On the other hand, in Experiment 2, it was confirmed that in Comparative Examples 4 and 5, bonding workability was also inferior to Examples 4, 5, 6, and 7. In particular, under the conditions of Comparative Example 5, the wrap portion was too large to perform the fitting operation. Therefore, in this case, the sealability could not be obtained. Further, under the conditions of Comparative Example 6, since the wrap portion is too small, only the same effect as in the case where there is no phase difference between α and β (for example, Example 1) can be obtained, and the sealing performance by providing the phase difference. The improvement effect could not be confirmed.

  From Experiments 1 and 2, it was confirmed that the portion with the portion 16 that wraps within an appropriate range has better sealing performance.

FIG. 1 is a plan view of a joint sheet gasket according to an embodiment of the present invention. FIG. 2 is a schematic view showing a cross-sectional shape of the combined end portion of the annular divided body constituting the joint sheet gasket shown in FIG. FIG. 3 is a schematic view showing a cross-sectional structure before and after assembly of the joint sheet shown in FIG. FIG. 4 is a schematic view showing a cross-sectional structure before and after assembly of a joint sheet according to another embodiment of the present invention. 5 (A), (B), and (C) are cross-sectional views of combined end portions of a joint sheet made of a conventional divided body. FIG. 6 is a schematic view showing a cross-sectional structure before and after assembly of a conventional divided body.

Explanation of symbols

10 Joint sheet gasket 12a, 12b End portion 16 Lapping portion 20 Dovetail groove α, β Inclination angle t Thickness u Edge width

Claims (5)

A joint sheet gasket configured by assembling together ends of a plurality of annular divided bodies formed by punching plate-shaped gasket material,
While forming one end and the other end of the annular divided body as a dovetail groove having a shape substantially complementary to each other,
Each butted end face including these dovetail grooves is formed such that the end face of at least one of the divided bodies is inclined obliquely in the thickness direction.   2. The joint sheet according to claim 1, wherein when the two divided bodies of the butt end faces are formed to be inclined obliquely, the inclination angles in the thickness direction are in the range of 45 ° to 85 °, respectively. gasket.   The joint sheet gasket according to claim 1 or 2, wherein a phase difference is provided in advance in the inclination angle so that each butted end face of the annular divided body wraps in a state before tightening.   The joint sheet gasket according to claim 4, wherein the phase difference is in a range of 5 ° to 25 °. The inclined angle on the side inclined obliquely is in the range of 65 ° to 85 ° when the split body on only one side of the butt end surface is inclined obliquely and the other is formed at a right angle. The joint sheet gasket described.

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