JPH0557881U - Power equipment container gasket - Google Patents

Abstract

(57) [Summary] [Purpose] A gasket that has a high sealing property and that provides a stable sealing effect for a long period of time. [Structure] The gasket 8 is integrally formed in a seamless loop shape. Attach the mounting surface 8a of the gasket 8 to the mounting portion 7 of the board.
And the pressing surface of the cover 5 presses the sealing surface 8b. Since the main ridge 8d is provided in the direction orthogonal to the pressing surface of the cover 5, it is simply compressed without being bent left and right. As a result, high sealing performance is exhibited. Secondary ridge 8
Since e and 8f are provided beside the main ridge 8d and sealed, the main ridge 8d is protected from the outside air that causes deterioration.
As a result, the main ridge 8d exhibits a stable sealing property for a long period of time.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a gasket used for a power equipment container.

[0002]

[Prior Art]

 For electric power equipment containers that may be installed in the open-air condition, contain sulfur hexafluoride gas to enhance the electrical insulation inside the container, or seal the container to protect the stored equipment and parts from moisture. ing. For this reason, a gasket is interposed between the mounting portion and the joint portion of the container cover for sealing.

Here, as the gasket made of an elastic material such as rubber or synthetic resin, a gasket having a circular cross section or a rectangular cross section is used. However, if there is only one ridge on the sealing surface that makes elastic contact with the cover and seals, dust will adhere to the outside of the ridge or it will be directly exposed to rainwater, so it will oxidize early and lose its elasticity. There were cases where cracks occurred and the sealability was lost. For this reason, as shown in FIG. 9, there has been devised a gasket in which the cross-sectional shape of the seal surface is composed of two symmetrical ridges 28e and 28f, and the seal surface has two steps. According to this, since the outer ridge 28e blocks dust and water, the inner ridge 28f is protected from the outside air and the inner ridge 28f is prevented from being deteriorated early. Therefore, compared to a gasket that has only one sealing surface, the gasket as a whole exhibits stable sealing performance over a long period of time.

[0004]

[Problems to be solved by the device]

 However, in the gasket provided with the ridges 28e and 28f, bending stress is applied to the ridges 28e and 28f so as to spread to both sides, and the surface of the ridge 28f exhibiting the sealing property is in a pulled state. However, if the sealability is not sufficient, and if it is maintained under a condition where a large tensile stress is applied, the deterioration of the material will progress relatively faster than in the case of no load, and the long-term reliability is still insufficient. there were.

In order to solve such a technical problem, the present invention intends to provide a gasket having a high sealing property and a stable sealing effect for a long period of time.

[0006]

[Means for Solving the Problems]

 Therefore, in this invention, in a gasket integrally formed in a loop shape, having a mounting surface to be mounted on the mounting portion of the substrate and a sealing surface to be elastically attached to the cover, the sealing surface is orthogonal to the pressing surface of the cover. A main ridge that is pressed and compressed in the direction and a sub ridge that is arranged on the lateral side of the main ridge are provided.

[0007]

[Action]

 In this invention, the gasket is attached by the attachment surface to the attachment portion provided on the substrate around the opening of the power equipment container. Since this gasket is integrally molded into a seamless loop, there are no locally missing seals.

When the cover is attached to this substrate, the main ridges are pressed in a direction orthogonal to the pressing surface of the cover, and are simply compressed without being bent to the left or the right, so that high sealability is achieved. Exert.

Further, the sub-projection line which is pressed by the pressing surface of the cover is arranged on the side of the main projection line so as to prevent the main projection line from being exposed to outside air or rainwater which causes deterioration. This prevents the main ridges from deteriorating and maintains stable sealing performance for a long period of time.

[0010]

[Effect of the device]

 As described above, this invention has a mounting surface to be mounted on the mounting portion of the substrate and a sealing surface that elastically contacts the cover, and in a gasket integrally formed in a loop shape, the sealing surface is the pressing surface of the cover. Since the main ridges that are pressed and compressed in the orthogonal direction and the sub ridges that are arranged on the side of the main ridges are provided, high sealing performance is exhibited for a long period of time.

[0011]

【Example】

 Hereinafter, an example of the gasket in which the present invention is applied to the disconnecting switch operating device 1 will be described in detail with reference to FIGS. 1 to 6.

In the disconnector, an operating unit for opening and closing the electric circuit is provided on an upper part of a mount (not shown), and an operating device for operating this operating unit is attached to the mount. As shown in FIG. 1, this operating device is housed in an equipment box 1 and a terminal box 2 provided on the side surface of the equipment box 1. In the equipment box 1, in addition to the drive motor 3 that is the drive source of the operating section, necessary equipment such as a relay (not shown) is housed. Further, a drive shaft 4 of a drive motor 3 is connected to an upper portion of the equipment box 1 so as to extend to a working portion. In addition, various terminals and operators for manually operating the disconnecting switch during inspection are housed in the terminal box 2.

The device box 1 has an opening on the front surface, and an attachment flange 6 for attaching and fixing the cover 5 is integrally formed on the periphery of the opening, and an attachment portion 7 formed to project forward in a rectangular shape is provided so as to project. A gasket 8 is fitted on the front end. Then, the gasket 8 is pressed by the inner side surface, and the cover 5 is attached and fixed to the attachment flange 6 by a plurality of attachment bolts 9.

As shown in FIG. 2, the attachment portion 7 is formed of a plate material having a plate thickness of about 6 mm in a substantially rectangular loop shape. As shown in FIG. 3, the cover 5 has a dish-like shape with its peripheral edge bent, and is fixed to a mounting flange 6 by a mounting bolt 9. As a result, the gasket 8 attached to the tip of the attachment portion 7 makes elastic contact with the inner surface (pressing surface) of the cover 5 to seal the front opening of the equipment box 1.

As shown in FIG. 1, the gasket 8 is formed by integrally forming an elastic rubber material in a loop shape and does not have a joint. Therefore, the gasket 8 can be sealed without locally losing the sealing property such as the joint. Has been done. Further, as shown in FIG. 2, this cross section is composed of a mounting surface 8a to be fitted and mounted on the mounting portion 7 and a sealing surface 8b elastically contacting with the cover 5, and the mounting surface 8a has a concave portion to be fitted to the mounting portion 7. Article 8c is provided. On the sealing surface 8b of the gasket 8, a main ridge 8d that bulges in an arc is formed on the central axis m. As shown in FIG. 2, the central axis m is a line orthogonal to the pressing surface of the cover 5 when pressed by the cover 5, and a simple compressive force is applied to the main ridge 8d, so Also, it is designed not to generate bending force that causes bending. Sub-projections 8e and 8f are formed on the left and right of the main projection 8d at the same height as the main projection 8d, and like the main projection 8d, they make elastic contact when the cover 5 is closed. .. The sub-projections 8e and 8f are bent and pressed outward with respect to the mounting portion 7, respectively. Further, grease is applied to the surface of the sealing surface 8b before attaching the cover 5 to further enhance the sealing property.

Next, the operation of this embodiment will be described.

As shown in FIG. 3, the cover 5 is covered with the gasket 8 fitted and fitted to the mounting portion 7, and the mounting bolt 9 is tightened. Then, the inside of the cover 5 comes into contact with the sealing surface 8b of the gasket 8 and is sequentially elastically deformed. At this time, in this embodiment, since the main ridge 8d bulges on the central axis m, it is deformed by being applied with a simple compressive force. For this reason, the strain is averaged in any part of the main ridge 8d, and the main ridge 8d is compressed without generating a locally large strain.

Further, a bending stress in the arrow X direction shown in FIG. 3 is applied to the outer sub-ridge 8e, and the outer sub-ridge 8e is curved and deformed outward to make elastic contact. Therefore, rainwater and dust are prevented from entering the main ridges 8d. In addition, bending stress in the direction of the arrow Y is applied to the sub-projection 8f on the inside, and the sub-projection 8f bends and deforms inward and makes elastic contact. Therefore, it is possible to prevent the oxidant from the device box 1 from entering the main protrusion 8d. As described above, the main ridges 8d are protected from the oxidant by the sub-ridges 8e and 8f, and the elasticity is maintained without deterioration for a long period of time, and the sealing property is maintained. Further, since the sealing surface 8b is further coated with grease, the sealing property can be further improved.

Now, in order to confirm the sealing property of the gasket 8 of this example, the amount of leaked air was measured.

The material of the gasket of the measurement sample was ethylene propylene rubber, and the hardness was 70 ± 5 °, the tensile strength was 100 kg / cm ² or more, the elongation was 380% or more, and the usable temperature was -40 ° C to 120 ° C. Further, as shown in FIG. 5, in order to attach the gasket to the attachment portion 76 of the equipment box 1, a gasket integrally formed in a substantially rectangular loop shape having a horizontal dimension a of 450 mm and a vertical dimension b of 550 mm was manufactured.

As for the cross-sectional shape of the gasket, the gasket shown in FIG. 4 was used as an example, and a gasket having a left and right convex ridges 28d formed at two locations on the sealing surface as shown in FIG. 9 was used as a comparative example. .. The dimensions of each part are as shown in Table 1.

[0022]

[Table 1] The operating equipment used in the test was designed so that the drive shaft 4 of the equipment box 1, the manual operating device, the connection hole with the terminal box 2, etc. were completely sealed so that the leaker amount only at the mounting portion 7 could be measured. After the inside of the equipment box 1 was evacuated, sulfur hexafluoride gas was injected at 1.52 kg / cm ² . Further, after heating and cooling by a heat cycle described later was repeated to stabilize the test system, the periphery of the cover 5 was covered with a polyethylene container of known volume and sealed. After sealing, after a predetermined accumulation time, the concentration of sulfur hexafluoride gas in the polyethylene container was measured by a leak detector, and the leak amount was obtained from this.

In the test, as shown in FIG. 6, the operating equipment was housed in a cooling heater, held at −40 ° C. for 6 hours, heated over 2 hours and held at + 60 ° C. for 6 hours, and further 2 hours. One heat cycle was a cycle of -40 ° C over time. In the example, after the completion of 17 heat cycles, each temperature was kept at room temperature (23 ° C.), −40 ° C. and + 60 ° C., then covered with a polyethylene container and kept at each temperature for a predetermined accumulation time, and then the leak amount was changed. I asked. The results are shown in Table 2.

[0024]

[Table 2] In the comparative example, a cycle of holding at −20 ° C. for 6 hours, raising the temperature over 2 hours and holding at + 60 ° C. for 6 hours, and then raising to −20 ° C. over 2 hours was set as one heat cycle. After completion of the heat cycle, the temperature was kept at room temperature (23 ° C.), −20 ° C. and + 60 ° C., and then the leakage amount was obtained. The results are shown in Table 3.

[0025]

[Table 3] Note that, unlike the example, the low temperature side of the heat cycle was set to -20 ° C because the amount of leaked air became extremely large when it was lowered to -40 ° C, and the concentration measurement by the leak detector became impossible. is there.

[0026] Table 2 and the test results of Table 3, the air leakage amount of the examples were confirmed to be significantly reduced with less than one 10 ⁴ minutes of air leakage amount of the comparative example.

In this embodiment, the main convex ridge 8d is formed in the center of the seal surface 8b, and the sub convex ridges 8e and 8f are formed on the left and right sides. The outside air and the gas inside the equipment box 1 are blocked by 8 f, and the main ridges 8 d can be protected from oxidative deterioration, and a gasket having a stable sealing property for a long time can be obtained.

In this embodiment, the groove 8c is formed on the mounting surface 8a and is fitted to the mounting portion 7. However, the groove is formed on the mounting side of the equipment box 1 and the gasket 8 is The mounting surface 8c can be arbitrarily selected, for example, the mounting surface 8c can be fitted in the groove.

Further, in this embodiment, the main convex ridge 8d is formed in the center of the sealing surface 8b, and the sub ridges 8e and 8f are formed on the left and right sides to form a three-mount gasket. Any material may be used as long as a compressive force is applied and the outside air is blocked by the sub-ridge 8e provided on the outside. Therefore, as shown in FIG. 7 and FIG. 8, the gasket may be a two-ridged gasket in which a thin sub-projection 8e is formed on the outer side of the main projection 8d. can do.

[Brief description of drawings]

FIG. 1 is a front view of an operating device in which a part of a cover is cut away.

FIG. 2 is a sectional view showing a mounting state of a gasket.

FIG. 3 is a cross-sectional view with a cover attached.

FIG. 4 is an end view of the gasket.

FIG. 5 is a front view of a gasket.

FIG. 6 is a process diagram showing a heat cycle of an air leak test.

FIG. 7 is a cross-sectional view showing a mounted state of another gasket.

FIG. 8 is a cross-sectional view showing a state where a cover of another example is attached.

FIG. 9 is an end view of a conventional gasket.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Equipment box 5 ... Cover 7 ... Mounting part 8 ... Gasket 8a ... Mounting surface 8b ... Sealing surface 8d ... Main convex line 8e ... Sub convex line

Claims (1)

[Scope of utility model registration request] 1. A mounting surface to be mounted on a mounting portion of a board,
A gasket integrally formed in a loop shape having a sealing surface elastically contacting the cover, wherein the sealing surface is a main ridge that is pressed and compressed in a direction orthogonal to the pressing surface of the cover, and a lateral side of the main ridge. A gasket for an electric power equipment container provided with a sub ridge arranged on the.