JP3698877B2 - Sealed container for electrical equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to sealed containers for electrical equipment provided with a seal packing between the case body and the lid member.
[0002]
[Prior art]
Japanese Utility Model Laid-Open No. 58-56251 discloses a case main body provided with an annular flange portion that is continuous over the entire circumference of the opening, an annular seal packing that is made of an elastic material and is fitted to the flange portion, There are disclosed a sealed container for an electric device including a lid member attached to a case body so as to press the seal packing against a flange portion and close an opening of the case body, and a seal packing used for the sealed container. In the structure shown in FIG. 4 of this publication, the flange portion has a curved cross-sectional shape that is convex upward, and the seal packing is bonded to the curved outer surface of the flange. It is pasted using. Furthermore, the seal packing shown in FIG. 7 (b) has a convex portion (thick portion) at the center of the outer surface. This convex portion is compressed and deformed to constitute a seal portion.
[0003]
FIGS. 1 to 3 of Japanese Utility Model Publication No. 2-19661 each show a seal packing fixed to an annular flange portion provided in an opening of a case body of a sealed container for oil-filled electrical equipment by a fitting structure. An example of is shown. The annular flange portion has a shape spreading in a trumpet shape, and a relatively deep annular groove portion into which the flange portion is inserted and fitted is formed in the seal packing.
[0004]
[Problems to be solved by the invention]
In the seal structure disclosed in Japanese Utility Model Laid-Open No. 58-56251, since an adhesive is required for fixing the seal packing, there is a problem that the mounting work of the seal packing becomes troublesome. In addition, the sealing structure as shown in Japanese Utility Model Publication No. 2-19661 has a low sealing performance. One of the causes is that the shape of the opening of the case body is distorted by the heat generated when the mounting brackets are welded to the outside of the case body, and the seal is formed between the flange portion and the seal packing fitted by this distortion. A gap that reduces the performance is formed. Another cause is that when the case body and the lid member are plated with zinc plating or the like and further coated with a resin paint, the surface becomes rough, and between these members and the seal packing, Adhesiveness is deteriorated.
[0005]
An object of the present invention, the mounting of the seal packing is easy, yet to provide a high have electrical equipment for sealed containers of sealability.
[0006]
[Means for Solving the Problems]
The present invention includes a case main body provided with an annular flange portion that is continuous over the entire circumference in the opening, an annular seal packing that is formed of an elastic material and is fitted to the flange portion, and presses the seal packing against the flange portion. In addition, a sealed container including a lid member attached to the case main body so as to close the opening of the case main body is an object. In the case where the sealed container is a sealed container for electrical equipment that houses electrical equipment such as a transformer, the case body and the lid member are made of metal. In this case, when the inside of the sealed container for electrical equipment is filled with insulating oil or the like, it is preferable that the shape of the flange portion has a cross-sectional shape curved so as to be convex upward. . And in order to improve corrosion resistance, the case main body and the lid member may each be coated by coating after being plated by galvanization or the like.
[0007]
The seal packing used in the present invention includes an annular flange-side facing surface portion that faces the annular outer surface of the flange portion, a lid-side facing surface portion that faces the flange-side facing surface portion and faces the inner wall surface of the lid member. And an engaging portion that engages with the annular edge of the flange portion. The flange-side facing surface portion of the seal packing has a plurality of concentrically arranged lower convex portions that extend along the entire circumference of the flange-side facing surface portion, that is, along the flange-facing surface portion and project toward the flange portion side. Are provided integrally. In addition, a plurality of concentrically arranged upper convex portions that extend along the lid side facing surface portion and project toward the lid member side are integrally provided on the lid side facing surface portion of the seal packing. The flange side facing surface part, the engaging part, and the plurality of lower convex parts are in a state where the engaging part is engaged with the edge of the flange part and the plurality of lower convex parts are in contact with the outer surface of the flange part. The shape is preferably determined so that the seal packing is fitted to the flange portion. Furthermore, the plurality of lower protrusions and the plurality of upper protrusions have a shape that forms a seal portion by being compressed and deformed in a state where the lid member is attached to the case body.
[0008]
According to the structure of the present invention, the seal packing can be attached to the flange portion of the case main body without using an adhesive by the engagement between the edge portion of the flange portion and the seal packing. In addition, the seal packing is integrally provided with a plurality of lower convex portions that come into contact with the flange portion and a plurality of upper convex portions that come into contact with the lid member. If the projecting dimensions and number of these lower and upper projections are set arbitrarily, even if the opening of the case body is distorted or the surface of the case body is rough, the flange portion and the seal packing A plurality of seals are formed concentrically between each other and between the lid member and the seal packing, thereby improving the sealing performance. Therefore, high sealing performance can be maintained even if a structure in which the seal packing is fitted to the flange portion of the case main body is employed. Further, when the seal portion is formed by the convex portion, the tightening force of the lid member to the case main body may be reduced, so that the stress applied to the seal packing is reduced correspondingly and the life of the seal packing is extended.
[0009]
In particular, when the flange portion has a cross-sectional shape curved so as to be convex upward, the plurality of upper convex portions has the number of upper convex portions located on the inner side of the apex of the flange portion. It is preferable to provide more than the number of the upper convex parts located outside the apex of the flange part. This is due to the following reason. First, a bending error is inherent in the bending process of the flange portion, and the seal packing may be partially pulled outward due to the processing error. In the portion where the seal packing is partially pulled outward, one or more upper convex portions which are originally inside the apex of the flange portion are often moved outward from the apex. When the number of the upper convex portions located inside the apex of the flange portion is smaller than the number of the upper convex portions located outside the apex of the flange portion, the sealing performance is obtained by the movement of the one or more upper convex portions. Decreases. Therefore, as described above, if the number of the upper convex portions positioned on the inner side of the apex of the flange portion is increased, it is possible to prevent the sealing performance from being deteriorated even if the upper convex portion is moved as described above.
[0010]
If the cross-sectional shape of the flange portion is almost arc-shaped, the cross-sectional shape of the lid-side facing surface portion and flange-side facing surface portion of the seal packing before fitting into the flange portion is the same as the cross-sectional shape of the flange portion. It is preferable to define a substantially arc shape so as to be substantially concentric. In this way, even if there is some processing error in the flange portion, the projecting dimension of the upper convex portion from the seal packing in a state where it is fitted to the flange portion hardly changes. In other words, even if the seal packing is partially pulled outward and the upper convex portion moves outward, the projecting dimension of the next upper convex portion that comes to a position corresponding to the apex of the flange portion is substantially the same. Therefore, the sealing performance does not change.
[0011]
In particular, when the cross-sectional shape of the flange portion has an arcuate cross-sectional shape that is convex upward, a plurality of lower convex portions are configured by the first and second convex portions, In the case where the upper convex portion is constituted by the third and fourth convex portions, it is preferable to arrange the first to fourth convex portions as follows. That is, in a state where the seal packing is fitted to the flange portion, the first convex portion and the second convex portion are substantially equal from the virtual cylindrical surface to the both sides of the virtual cylindrical surface passing through the apex of the flange portion. Arrange so that the gap dimension is opened. The virtual cylindrical surface is substantially concentric with the case body. Further, in a state where the seal packing is fitted to the flange portion, the third convex portion and the fourth convex portion are opened on both sides of the above-described virtual cylindrical surface with a second interval dimension substantially equal from the virtual cylindrical surface. Arrange as follows. When the first to fourth convex portions are arranged in this manner, the first to fourth convex portions and the opposing member (flange portion or lid member) can be brought into contact with each other. In particular, in this case, if the first gap dimension is smaller than the second gap dimension, the first to fourth protrusions are surely secured when the seal packing is sandwiched between the flange portion and the lid member. Compressive deformation to improve sealing performance.
[0012]
It is possible to adopt a structure in which the engaging part is constituted by a plurality of engaging pieces and is engaged with the edge of the flange part at intervals, but the engaging part is continuously engaged with the edge of the flange part. If it is formed in an annular shape so as to match, the sealing performance is further enhanced since the sealing portion is also formed in this engaging portion.
[0013]
Each of the first and second convex portions and the third and fourth convex portions only needs to constitute a seal portion. However, in consideration of moldability and sealability, the first and second convex portions are preferably arranged concentrically.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a partially omitted cross-sectional view of a main part of an example of an embodiment in which the present invention is applied to a sealed container (a sealed container for electrical equipment) of a transformer. 2 is a partially omitted cross-sectional view of the seal packing used in this embodiment, and FIG. 3 is an enlarged cross-sectional view of a part of this seal packing.
[0015]
In FIG. 1, reference numeral 1 denotes an iron case main body, and an annular flange portion 2 that is continuous over the entire circumference is integrally provided in an opening portion of a cylindrical tube portion 1a. After the case body is galvanized, a resin paint is cationically coated thereon. Although not shown, an iron fitting such as a fitting is fixed to the outside of the case body by welding. The flange portion 2 has a cross-sectional shape curved in an arc shape so as to protrude upward (in the direction in which the opening portion opens). Incidentally, when the thickness of the iron plate used for the case main body 1 is about 2 mm and the diameter of the cylindrical portion 1a of the case main body 1 is 500 mm, the radius of the arc of the flange portion 2 is about 7 to 8 mm.
[0016]
In FIG. 1, reference numeral 3 denotes an iron lid member. After the lid member 3 is also galvanized, a resin coating is cationically coated thereon. The lid member 3 includes a plate-like portion 3a facing the opening of the case body, and an annular flange portion 3b provided integrally with the outer periphery of the plate-like portion 3a and extending in a direction substantially orthogonal to the plate-like portion 3a. It is configured. The inner wall portion of the plate-like portion 3a of the lid member 3 facing the flange portion 2 of the case body 1 is formed flat. Although not shown, the attachment structure for attaching the lid member 3 to the case body 1 is a known structure.
[0017]
Reference numeral 4 denotes an annular seal packing formed of an elastic material such as nitrile rubber and fitted to the flange portion 2 of the case body 1. Needless to say, a reinforcing member such as a woven fabric may be embedded in the seal packing 4. The seal packing 4 is an annular flange-side facing surface portion 5 that faces the annular outer surface of the flange portion 2 that is curved upward, and a plate of the lid member 3 that faces the flange-side facing surface portion 5. It has a lid-side facing surface portion 6 that faces the inner wall surface of the shaped portion 3a, and an engaging portion 7 that engages with the annular edge 2a of the flange portion 2.
[0018]
As shown in an enlarged view in FIG. 3, the flange-side facing surface portion 5 includes an annular flat surface portion 5 a and an annular curved portion 5 b that is curved along the outer surface of the flange portion 2. The curved portion 5b of the flange-side facing surface portion 5 of the seal packing 4 extends over the entire circumference of the flange-side facing surface portion 5, that is, extends along the flange-side facing surface portion 5 and toward the flange portion 2 side (flange-side facing surface portion 5 The first convex portion 8 that protrudes in the direction away from the first convex portion 8 and the outer periphery of the first convex portion 8 (outside in the radial direction of the case body 1) over the entire circumference of the flange-side facing surface portion 5. An annular second convex portion 9 that extends and projects toward the flange portion 2 side is integrally provided. These 1st and 2nd convex parts 8 and 9 comprise the lower side convex part. In addition, the lid-side facing surface portion 6 of the seal packing 4 has an annular third surface extending over the entire circumference of the lid-side facing surface portion 6 and projecting toward the lid member 3 side (in a direction away from the lid-side facing surface portion 6). The convex portion 10 and the annular fourth convex portion 11 that are located outside the third convex portion 10 and extend over the entire circumference of the lid-side facing surface portion 6 and project toward the lid member 3 side are integrally formed. Is provided. The third and fourth convex portions 10 and 11 constitute an upper convex portion.
[0019]
The first and second convex portions 8 and 9 are arranged concentrically so as to open a first interval dimension L1 that is equal to both sides of the virtual cylindrical surface 12 passing through the apex of the flange portion 2, and the third The convex portion 10 and the fourth convex portion 11 are concentrically arranged on both sides of the virtual cylindrical surface 12 so as to open a second distance L2 that is substantially equal from the virtual cylindrical surface. In this example, the first gap dimension L1 is set to about 2.5 mm, the second gap dimension L2 is set to about 3 mm, and the first gap dimension L1 is made smaller than the second gap dimension L2. Incidentally, the radius of curvature of the outer surfaces of the first and second convex portions 8 and 9 in this example is about 0.5 mm, and the radius of curvature of the outer surfaces of the third and fourth convex portions 10 and 11 is about 1 mm. is there.
[0020]
The inventor initially considered providing an annular convex portion on each of the flange-side facing surface portion 5 and the lid-side facing surface portion 6 of the seal packing. However, it has been found that a single convex portion does not necessarily provide sufficient sealing performance. Therefore, in the present invention, as described above, two convex portions are provided on each of the flange-side facing surface portion 5 and the lid-side facing surface portion 6.
[0021]
The engaging portion 7 has an annular shape so as to be continuously engaged with the edge 2 a of the flange portion 2 of the case body 1 over the entire circumference. The engaging portion 7 has a shape in which the cross-sectional shape has a hook shape. In this example, the flange side facing surface portion 5 of the seal packing 4, the engaging portion 7, and the first and second convex portions 8 and 9 are engaged with the edge portion 2 a of the flange portion 2. In a state where the first and second convex portions 8 and 9 are in contact with the outer surface of the flange portion 2, the shape and dimensions are such that the seal packing 4 is firmly fitted to the flange portion 2 and cannot be easily detached. It has been established. The first to fourth protrusions 8 to 11 are in a state where the lid member 3 is attached to the case body 1 so as to press the seal packing 4 against the flange portion 2 of the case body 1 and close the opening of the case body 1. Thus, the shape is determined so as to form a seal portion by compressing and deforming each. In this example, the internal dimension of the seal packing 4 is set to be approximately 2.5% smaller than the external dimension of the flange portion 2. A double seal between the flange portion 2 and the seal packing 4 is constituted by the first and second convex portions 8 and 9, and the seal packing 4 and the lid member 3 are constituted by the third and fourth convex portions 10 and 11. A double seal between is constructed.
[0022]
In the above example, by making the first distance dimension L1 between the first and second convex parts 8 and 9 smaller than the second distance dimension L2 between the third and fourth convex parts 10 and 11, The sealing performance is enhanced by ensuring the compressive deformation of the first to fourth convex portions when the seal packing 4 is sandwiched between the flange portion 2 and the lid member 3. However, when the radius of curvature of the flange portion 2 is increased, the relationship between the first interval dimension and the second interval dimension may be reversed. Furthermore, the first gap dimension and the second gap dimension can be substantially matched by appropriately selecting the elastic modulus of the seal packing 4 and the projecting dimensions of the first to fourth protrusions.
[0023]
Moreover, in the said example, although the engaging part 7 is formed in cyclic | annular form, of course, you may comprise the engaging part by the some engagement piece arrange | positioned at intervals in the circumferential direction.
[0024]
FIG. 4 shows a cross-sectional shape of a part of another seal packing 24 that can be used in the present invention (the hatching indicating the cross section is omitted for easy understanding). The seal packing 24 is suitable for being attached to the flange portion 2 having a circular cross section shown in FIG. 1, and can be used in place of the seal packing 4 of FIG. In order to clarify the dimensional difference from the seal packing 4 in FIG. 1, the cross-sectional shape of the seal packing 4 is shown in FIG. In FIG. 4, the same reference numerals as those shown in FIGS. 1 to 3 are given the same reference numerals as those shown in FIGS.
[0025]
The seal packing 24 is located at a position facing the flange-side facing surface portion 25 and an annular flange-side facing surface portion 25 facing the annular outer surface of the flange portion 2 (FIG. 1) that is convexly curved upward. The lid member 3 (FIG. 1) engages with the lid-side facing surface portion 26 facing the inner wall surface of the plate-like portion 3a (FIG. 1) and the annular edge 2a (FIG. 1) of the flange portion 2 (FIG. 1). And an engaging portion 27. The flange-side facing surface portion 25 has an annular flat surface portion 25a and an annular curved portion 25b whose cross-sectional shape is curved along the outer surface of the flange portion 2 (FIG. 1) curved in an arc shape. ing. The curved portion 25b of the flange side facing surface portion 25 of the seal packing 24 extends annularly over the entire circumference of the flange side facing surface portion 5 and protrudes toward the flange portion 2 side (in a direction away from the flange side facing surface portion 25). The eight lower convex portions 28 are integrally provided. The cross-sectional shape of these lower convex portions 28 has a triangular shape that protrudes downward. Further, one lower convex portion 28 is provided at a position that coincides with the virtual cylindrical surface 32 passing through the apex of the flange portion 2, four lower convex portions 28 are provided inside thereof, and three lower sides are provided outside thereof. A convex portion 28 is provided. In other words, the number of the lower protrusions 28 on the inner side is larger than the number of the lower protrusions 28 on the outer side than the apex of the flange portion 2.
[0026]
The lid-side facing surface portion 26 of the seal packing 24 is concentrically curved with the curved portion 25b of the flange-side facing surface portion 25, and extends over the entire circumference of the lid-side facing surface portion 26 on the lid member 3 (see FIG. 1) Thirteen annular upper convex portions 30 projecting toward the side (in a direction away from the lid-side facing surface portion 26) are integrally provided. These upper convex portions 30 also have a triangular shape whose cross section is convex upward, and are all arranged concentrically. The interval between the upper protrusions 30 is substantially constant. The protrusion dimension of the upper protrusions 30 is approximately 1.5 times larger than the protrusion dimension of the lower protrusions 28. One upper convex portion 30 is provided at a position coinciding with the virtual cylindrical surface 32 passing through the apex of the flange portion 2 (FIG. 1), seven upper convex portions 30 are provided on the inner side, and five upper convex portions are provided on the outer side. A convex portion 30 is provided. In other words, the number of the upper convex portions 30 on the inner side than the apex of the flange portion 2 is larger than the number of the lower convex portions 30 on the outer side.
[0027]
When the number of the upper protrusions 30 positioned inside the apex of the flange portion is larger than the number of the upper protrusions 30 positioned outside the apex of the flange portion, the seal packing is caused by a processing error caused by the bending process of the flange portion. Even if 24 is partially pulled outward, in the portion where seal packing 24 is partially pulled outward, one or more upper protrusions 30 that are originally inside the apex of the flange portion are Move outside the vertices. When the number of the upper convex portions 30 located inside the apex of the flange portion is smaller than the number of the upper convex portions 30 located outside the apex of the flange portion, the movement of the one or more upper convex portions Sealing performance is reduced.
[0028]
In the above example, the present invention is applied to a sealed container for electrical equipment, but the present invention can naturally be applied to other sealed containers.
[0029]
【The invention's effect】
According to the present invention, the seal packing can be attached to the flange portion of the case main body without using an adhesive by the engagement between the edge portion of the flange portion and the seal packing. Also, since the seal packing is provided with a plurality of lower projections that come into contact with the flange portion and a plurality of upper projections that come into contact with the cover member, the opening of the case body may be distorted or the surface of the case body Even if the surface is rough, a plurality of seals can be formed between the flange portion and the seal packing and between the lid member and the seal packing, and the seal packing is fitted to the flange portion of the case body. Even if is adopted, there is an advantage that the sealing performance can be maintained high.
[Brief description of the drawings]
FIG. 1 is a partially omitted cross-sectional view of a main part of an example of an embodiment in which the present invention is applied to a sealed container of a transformer.
2 is a partially omitted cross-sectional view of a seal packing used in the embodiment of FIG.
FIG. 3 is an enlarged cross-sectional view of a part of the seal packing of FIG.
FIG. 4 is a diagram showing a partial cross-sectional shape of another seal packing that can be used in the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Case main body 2 Flange part 3 Lid member 4,24 Seal packing 5,25 Flange side opposing surface part 6,26 Lid side opposing surface part 7,27 Engagement part 8,9,28 Lower convex part 10,11,30 Upper convex part Part

Claims (4)

A metal case body provided with an annular flange portion that is continuous over the entire circumference in the opening;
An annular seal packing formed of an elastic material and fitted into the flange portion;
A metal lid member attached to the case body so as to press the seal packing against the flange portion and close the opening of the case body;
A sealed container for electrical equipment having a cross-sectional shape curved so that the flange portion is convex upward,
The seal packing has an annular flange-side facing surface portion that faces the annular outer surface of the flange portion that is convexly curved upward, and an inner wall surface of the lid member that is located at a position facing the flange-side facing surface portion. And a lid-side facing surface portion that is opposed to, and an engaging portion that engages with an annular edge portion of the flange portion,
The flange side facing surface portion of the seal packing is integrally provided with a plurality of annular lower convex portions extending along the flange side facing surface portion and projecting toward the flange portion side and arranged concentrically,
The lid-side facing surface portion of the seal packing is integrally provided with a plurality of concentrically arranged upper convex portions that extend along the lid-side facing surface portion and project toward the lid member side,
The plurality of lower convex portions and the plurality of upper convex portions are shaped so as to form a seal portion by compressing and deforming in a state where the lid member is attached to the case body,
The plurality of upper convex portions are provided such that the number of the upper convex portions located inside the apex of the flange portion is larger than the number of the upper convex portions located outside the apex of the flange portion. A sealed container for electrical equipment, wherein The cross-sectional shape of the flange portion is substantially arcuate,
The cross-sectional shape of the lid-side facing surface portion and the flange-side facing surface portion of the seal packing before being fitted to the flange portion is substantially arcuate so as to be substantially concentric with the cross-sectional shape of the flange portion. The sealed container for electrical equipment according to claim 1, which is presented. 2. The sealed container for electrical equipment according to claim 1, wherein the engaging portion has an annular shape so as to be continuously engaged with the edge portion of the flange portion. A metal case body provided with an annular flange portion that is continuous over the entire circumference in the opening;
An annular seal packing formed of an elastic material and fitted into the flange portion;
A metal lid member attached to the case body so as to press the seal packing against the flange portion and close the opening of the case body;
A sealed container for electrical equipment having a cross-sectional shape curved so that the flange portion is convex upward,
The seal packing has an annular flange-side facing surface portion that faces the annular outer surface of the flange portion that is convexly curved upward, and an inner wall surface of the lid member that is located at a position facing the flange-side facing surface portion. And a lid-side facing surface portion that is opposed to, and an engaging portion that engages with an annular edge portion of the flange portion,
The flange side facing surface portion of the seal packing is located outside the first convex portion and the annular first convex portion that extends along the flange side facing surface portion and protrudes toward the flange portion side. An annular second convex portion that extends along the entire circumference and protrudes toward the flange portion side is integrally provided,
The lid side opposing surface portion of the seal packing is positioned outside the third convex portion and the annular third convex portion extending along the lid side opposing surface portion and projecting toward the lid member side. An annular fourth convex portion that extends along the lid-side facing surface portion and protrudes toward the lid member side is integrally provided,
The first to fourth convex portions are shaped so as to form a seal portion by being compressed and deformed in a state where the lid member is attached to the case body,
The cross-sectional shape of the flange portion has an arc shape,
In a state where the seal packing is fitted to the flange portion, the first convex portion and the second convex portion are substantially from both sides of the virtual cylindrical surface passing through the apex of the flange portion from the virtual cylindrical surface. Arranged to open equal first spacing dimensions;
In a state in which the seal packing is fitted to the flange portion, the third convex portion and the fourth convex portion have a second spacing dimension that is substantially equal from the virtual cylindrical surface to both sides of the virtual cylindrical surface. Arranged to open,
The sealed container for electrical equipment, wherein the first distance dimension is smaller than the second distance dimension.

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