CN113451982A

CN113451982A - Cold contraction sealing member with built-in sealing layer

Info

Publication number: CN113451982A
Application number: CN202010231536.XA
Authority: CN
Inventors: 宋斌; 周东; 朱栋栋; 朱思友
Original assignee: Shenzhen Cotran New Material Co ltd
Current assignee: Shenzhen Cotran New Material Co ltd
Priority date: 2020-03-27
Filing date: 2020-03-27
Publication date: 2021-09-28

Abstract

The embodiment of the invention relates to a sealing element with a built-in sealing layer, which is characterized by comprising a main body tube structure unit and a clamping unit; the main body pipe structure unit comprises an elastic cold shrinkage pipe, a joint for connecting the clamping unit and a middle part for connecting the cold shrinkage pipe and the joint; a tube core part which can be drawn away is arranged in the cold shrinkage tube and is used for expanding the cold shrinkage tube; arranging a sealing layer between the tube core part and the cold-shrink tube; the clamping unit can be detachably connected with a cable connecting port of equipment; the clamping unit is at least partially arranged in the joint, and a sealing structure for blocking the cable connecting port from being exposed outside is arranged at a proper position on the outer surface of the joint. The sealing element of the embodiment of the invention can be repeatedly used.

Description

Cold contraction sealing member with built-in sealing layer

Technical Field

The present invention relates to a sealing member, and more particularly, to a cold shrink sealing member for a built-in sealing layer of a communication cable, a power cable, or the like.

Background

In the technical fields of electric power, communication and the like, various electric power cables and communication cables are required to be used for transmitting electric energy and signals, communication equipment and electric power equipment are connected with the cables through cable connectors, and sealing protection is required during connection so as to prevent water, moisture, dust and damage. In the prior art, cold shrink sleeves are mainly used for sealing.

The cold-shrink tube is made of elastic material into a cold-shrink sheath, and the spiral tube core part is arranged in the cold-shrink sheath for supporting and expanding. When the cold-shrink sleeve is used, the cold-shrink sleeve is sleeved at the tail end of a power cable or a communication cable or the joint of the cable and a cable connector or other parts, the spiral pipe core part is drawn out, the elastic cold-shrink sheath rebounds naturally and is tightly pressed and attached to other parts such as the cable and the cable connector, and therefore sealing is achieved, water, dust and the like cannot enter the sealing part, and naturally cannot enter communication equipment and power equipment through the sealing part. Such cold-shrink tube can only be used once, can not used repeatedly, and when sealed position need be dismantled, can only realize dismantling through destroying the cold-shrink tube that compresses tightly the laminating above that, the dismouting is inconvenient, brings inconvenience for the maintenance of equipment, maintenance. Moreover, with the rapid development of the technology, the equipment integration degree is continuously improved, the shapes of various cable connectors are more and more irregular, and the cold-shrink tube in the prior art is only a section of elastic circular tube, so that the sealing effect on the cable connectors with irregular shapes is poor.

Disclosure of Invention

To solve at least one of the above technical problems, an embodiment of the present invention proposes a cold-shrink seal.

<1> a sealing element with built-in sealing layer, comprising a main body pipe structure unit and a clamping unit; the main body pipe structure unit comprises an elastic cold shrinkage pipe, a joint for connecting the clamping unit and a middle part for connecting the cold shrinkage pipe and the joint; a tube core part which can be drawn away is arranged in the cold shrinkage tube and is used for expanding the cold shrinkage tube; disposing a sealing layer between the tube core and the cold shrink tube; the clamping unit can be detachably connected with a cable connecting port of equipment; the clamping unit is at least partially arranged in the joint, and a sealing structure for blocking a cable connecting port of the equipment from being exposed to the outside is arranged at a proper position on the outer surface of the joint.

<2> the seal member as stated in <1>, characterized in that the joint, the intermediate portion and the cold shrink tube are of an integrally molded structure.

<3> the seal of <1>, wherein the intermediate portion is a tube of cold shrink material, and the removable tube core portion extends from the cold shrink tube to the intermediate portion.

<4> the sealing member according to <1>, wherein the intermediate portion has a flexible and irregularly shaped tube structure, and is not pressed against the cable in a natural state in which the intermediate portion is not expanded.

<5> the sealing member as stated in <1>, characterized in that the joint comprises a joint body, a seal ring provided on an outer surface of a distal end of the joint body for sealing a cable connection port of the equipment, and a protrusion provided on the outer surface of the joint body near the seal ring for abutting against an outer end face of the cable connection port of the equipment.

<6> the seal member as stated in <5>, characterized in that said joint body, said packing and said projection are of an integrally molded structure.

<7> the seal member as stated in <5>, wherein said seal ring is disposed obliquely to the proximal end of the joint body.

<8> the seal according to <5>, wherein the projection protrudes beyond the tip end of the seal ring.

<9> the seal member as stated in <5>, wherein said protrusion is a hollow structure, and a hollow portion of said protrusion communicates with a hollow inner cavity of said joint body.

<10> the sealing member as stated in <1>, wherein said clamping unit is a hollow structure, and said clamping unit is disposed in said joint.

<11> the sealing member as stated in <10>, wherein said joint and said clamping unit each have a hollow square tubular structure.

<12> the sealing member as stated in <1>, wherein said latch unit is a push type latch unit structure.

<13> the sealing member according to <1>, wherein the clamping unit is enclosed by a plurality of walls each having a connecting end and a separating end, the walls being connected to each other via the connecting ends; among the walls, at least two walls that set up relatively are the elastic wall, be provided with the buckle structure that protrudes to the surface of joint unit on the distal end portion of elastic wall.

<14> the sealing member as stated in <13>, wherein said elastic wall is inclined toward an outer side of the clamping unit.

<15> the sealing member as stated in <13>, wherein a rib is provided on an outer surface of the latch unit along a circumferential direction of the latch unit; the connector comprises a connector body, a sealing ring and a protruding portion, wherein the sealing ring is arranged on the outer surface of the far end of the connector body, the protruding portion is arranged on the outer surface of the connector body and close to the sealing ring, the sealing ring is used for sealing a cable connecting port of the equipment, the protruding portion is used for abutting against the outer end face of the cable connecting port of the equipment, the protruding portion is of a hollow structure, the hollow portion of the protruding portion is communicated with the hollow inner cavity of the connector body, and the convex edge is contained in the hollow portion of the protruding portion.

<16> the sealing member according to <1>, wherein the main tube structure unit includes one or more cold shrink tubes, the number of the intermediate portions matches with that of the cold shrink tubes, each cold shrink tube is connected to the joint through one intermediate portion, the joint is one, and the clamping unit is one.

<17> the seal member as stated in <1>, wherein said seal layer is a mastic seal layer or a rubber seal layer.

The embodiment of the invention has the following beneficial effects: the cold-shrink sealing element provided by the embodiment of the invention can be suitable for various cable connectors, the cable connecting port of the connecting equipment can be detachably clamped by arranging the joint and the clamping unit, the sealing effect is good, the sealing connection mode is suitable for sealing the cable connector with an irregular shape, the disassembly is convenient, the equipment maintenance and repair are convenient, and the cable connector can be taken out without damaging the cold-shrink sealing element during the maintenance and repair, so that the cold-shrink sealing element can be repeatedly used.

Drawings

Fig. 1 is an exploded view of a sealing member according to an embodiment of the present invention.

Fig. 2 is another exploded view of the sealing member according to the embodiment of the present invention.

Fig. 3 is a schematic view of a main tube structure unit of the sealing member according to the embodiment of the present invention.

Fig. 4 is a cross-sectional view of an assembly structure of a sealing member according to an embodiment of the present invention.

Fig. 5 is a schematic structural diagram of a clamping unit of a sealing member according to an embodiment of the present invention.

FIG. 6 is a side view of a clamping unit of a seal according to an embodiment of the present invention.

Fig. 7 is a side view of an assembly structure of a sealing member according to an embodiment of the present invention.

Fig. 8 is a sectional view of an assembled structure of a sealing member according to an embodiment of the present invention.

Fig. 9 is a schematic structural diagram of another embodiment of a seal according to an embodiment of the present invention.

Fig. 10 is a schematic diagram of an application example of the sealing member according to the embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings. Those skilled in the art will appreciate that the present invention is not limited to the drawings and the following examples.

Referring to fig. 1 to 8, an embodiment of the present invention provides a cold-shrink seal, which may be used in fields such as communication, power, and the like, for sealing and protecting various cable connectors and devices, and the seal includes a main body tube structure unit 1, a clamping unit 2, a removable tube core portion 3, and a sealing layer 4; the main body tube structure unit 1 is a hollow structure and comprises a joint 11, an intermediate part 12 and an elastic cold shrink tube 13 which are sequentially connected, at least one part of the main body tube structure unit 1 is expanded and supported by the tube core part 3, for example, the cold shrink tube 13 is supported by the tube core part 3, or the intermediate part 12 and the cold shrink tube 13 are both supported by the tube core part 3, and after the tube core part 3 is pulled out, the cold shrink tube 13 is rebounded and pressed to be attached to a cable so as to seal the cable connector; the intermediate portion 12 connects the joint 11 and the cold shrink tube 13; the clamping unit 2 is at least partially arranged in the joint 11, and the clamping unit 2 is used for detachably clamping a cable connecting port H of the connecting equipment, so that at least the front end of the joint 11 can extend into the cable connecting port H of the equipment, and a sealing structure is arranged on the outer surface of the joint 11 at a proper position where the joint 11 is contacted with the cable connecting port H and used for blocking the cable connecting port H of the equipment from being exposed to the outside; the sealing layer 4 is arranged between the cold shrink tube 13 and the tube core 3 and provides an enhanced sealing of the cable after being pulled out of the tube core 3.

The main body tube structure unit 1 comprises a joint 11, an intermediate part 12 and an elastic cold shrink tube 13, wherein one end of the intermediate part 12 is connected with the joint 11, and the other end is connected with the cold shrink tube 13, preferably, the joint 11, the intermediate part 12 and the cold shrink tube 13 are of an integrally formed structure. The main body pipe structure unit 1 is preferably a rubber pipe, for example, made of rubber such as silicon rubber, which is commonly used in the art.

The joint 11 includes a joint body and a sealing structure, the sealing structure including: one or more sealing rings 111 provided on an outer surface of the joint body at an overlapping position where the joint body is inserted into the cable connection port; and a protrusion 112 provided on an outer surface of the header body at a termination where the header body is inserted into the cable connection port. Preferably, the joint body, the packing 111 and the protrusion 112 are formed as an integral structure. The fitting 11 is preferably of a generally hollow square tubular configuration having a generally square or rectangular cross-section.

The sealing ring 111 is arranged along the circumference of the connector body, and preferably, the sealing ring 111 is barb-shaped, i.e. it is inclined (as shown in fig. 4) in the direction opposite to the direction in which the connector body is inserted into the cable connection port (referred to as the proximal end). In use, the gasket 111 seals the inner surface of the cable connection port H of the device.

The protrusion 112 protrudes beyond the top end of the seal ring 111 (as shown in fig. 4), i.e., the outer diameter of the protrusion 112 is larger than the outer diameter of the seal ring 111. The protruding portion 112 can abut against the outer end face of the cable connecting port H of the device, and can play a role in limiting when the connector 11 is inserted, so that the connector 11 is prevented from being completely embedded into the cable connecting port H of the device, and can also form a seal with the outer end face of the cable connecting port H, thereby preventing water and dust from entering the device. Preferably, the protruding portion 112 is a hollow structure, and the hollow portion of the protruding portion 112 is communicated with the hollow inner cavity of the joint body.

Further preferably, a positioning portion 113 is disposed on an outer surface of the proximal end of the connector body, and is used for positioning a pressing position of the elastic wall of the clamping unit 2. The positioning portion 113 is, for example, a rib or bump structure, or is defined only by a mark provided on the surface. The positioning portion 113 is provided to help identify the pressed position of the card-connecting unit 2.

The middle portion 12 connects the cold shrink tube 13 and the joint 11, and the middle portion 12 is a flexible connecting portion and is configured not to be pressed and attached to the cable after being pulled out of the tube core portion 3. The intermediate portion 12 is a special-shaped tube, and the cross-sectional shape of one end thereof matches the joint 11, and the cross-sectional shape of the other end thereof matches the cold shrink tube 13. In the present invention, the "shaped pipe" means a structure other than a cylindrical pipe, of which the side development of the outer surface is neither a rectangular plane shape nor a square plane shape, but an irregular two-dimensional or three-dimensional structure and/or shape. Preferably, the intermediate portion 12 is also made of a cold-shrink material, and the intermediate portion 12 and the cold-shrink tube 13 are integrally formed using the same material as the cold-shrink tube 13.

Illustratively, the intermediate portion 12 may be a hollow cylinder, a hollow ellipsoid, a hollow cone, a hollow externally-protruding thread structure, and the like, and preferably, the intermediate portion 12 is a hollow cylinder, a hollow cone, or a hollow externally-protruding thread structure.

Preferably, the inner diameter of each part of the middle portion 12 is larger than the inner diameter of the cold shrink tube 13 (i.e., the inner diameter in the natural state without being expanded). When the cable connector is used, after the tube core part 3 is pulled out, the middle part 12 and the cold shrink tube 13 elastically retract, the cold shrink tube 13 is tightly pressed and attached to a cable, the inner diameter of the middle part 12 is large, and the cold shrink tube is not tightly attached to the cable (as shown in fig. 10), so that the middle part 12 can move along the cable and can retreat towards the cold shrink tube 13, an operation space for detaching the cable connector is provided, the cold shrink tube 13 does not need to be damaged, and the technical problem that the cold shrink tube can only be used once in the prior art is solved.

The cold shrink tube 13 is, for example, a hollow round tube. The cold shrink tube 13 is used to seal the cable to hermetically protect the cable connector (see fig. 10). The cold shrink tube 13 is expanded and supported by the tube core 3 when not in use, and can be naturally shrunk and tightly attached to the cable after being drawn out of the tube core 3 when in use.

The clamping unit 2 is connected with the joint 11 and has a hollow structure, preferably, the clamping unit 2 is arranged in the joint 11, for example, the outer surface of the clamping unit 2 is connected with the inner surface of the joint 11 through modified resin bonding, and the shape of the clamping unit 2 is matched with that of the joint 11. The clamping unit 2 has a clamping structure, and can clamp the cable connecting port H of the connection device, and such a clamping structure can use a structure suitable in the prior art, and the invention is not particularly limited. The clamping unit 2 may be made of materials such as polyetherimide, nylon, polyoxymethylene, polypropylene or polyphenylene sulfide.

Preferably, the clamping unit 2 is a pressing type clamping unit, and the side wall of the clamping unit 2 is pressed to enable the clamping structure of the clamping unit 2 to be clamped to the cable connecting port H of the equipment. Specifically, the pressing type clamping unit 2 is substantially in a hollow square tubular structure, and is enclosed by a first wall 21, a second wall 22, a third wall 23 and a fourth wall 24, wherein the first wall 21 and the third wall 23 are arranged oppositely, and the second wall 22 and the fourth wall 24 are arranged oppositely. The clamping unit 2 comprises a connection end and a separation end, the connection end is at the back (near end) and the separation end (far end) is at the front along the direction of inserting the cable connection port into the clamping unit, the connection end connects the four walls to each other, and the separation ends of the four walls are separated from each other.

In one embodiment, the first wall 21 and the third wall 23 project from the adjacent two walls in the distal direction of the clamping unit 2. The tip of the separation end of first wall 21 and third wall 23 is provided with respectively to outside extending outstanding buckle structure 25, and is preferred, and buckle structure 25's tip is provided with the inclined plane, directly pushes the joint unit to cable connector H and can the joint, need not to press, easy to assemble. Preferably, there is a gap between two adjacent walls of the clamping unit 2. Preferably, the first wall 21 and the third wall 23 are inclined toward the outside of the latch unit 2.

Preferably, on the outer surface of the clamping unit 2, a rib 26 is provided along the circumference of the clamping unit 2, said rib 26 being received in the hollow part of the protrusion 112 of said coupling 11. The connector 11 is made of an elastic material, when the connector 11 abuts against the outer end face of the cable connecting port, the sealing structure of the connector 11 can play a role in sealing, but the strength is insufficient, so that the sealing function and the limiting function are limited, the strength of the convex edge 26 is high, and the protruding portion 112 can be pressed and abutted against the outer end face of the cable connecting port H after clamping, so that the protruding portion 112 can be assisted to seal the outer end face of the cable connecting port H of the equipment and limit a cold-shrink sealing element.

The tube core portion 3 detachably abuts against the inner surface of the cold-shrink tube 13 of the main body tube structural unit 1, or the inner surfaces of the intermediate portion 12 and the cold-shrink tube body 13. The tube core 3 may be a cold-shrink tube core commonly used in the art, but the present invention is not limited thereto.

The sealing layer 4 is used for providing enhanced sealing performance for the cold-shrink sealing element, and preferably, the sealing layer 4 is a daub sealing layer or a rubber sealing layer. The sealing performance of the cold-shrink sealing element can be obviously improved by adopting the sealing layer.

Referring to fig. 9, in another embodiment, the main body tube structural unit 1 of the cold-shrink seal of the present invention may also be embodied as a united tube portion 1, and specifically, the cold-shrink seal of this embodiment includes the united main body tube structural unit 1, one click unit 2, and a plurality of tube core portions 3; the integrated main body tube structure unit 1 comprises a joint 11, a plurality of intermediate parts 12, for example, 2, 3, 4, 5 and 6, which can be selected according to actual requirements, and a plurality of cold-shrink tubes 13 matched with the intermediate parts 12, wherein the intermediate parts 12 are correspondingly connected with the cold-shrink tubes 13 one by one, and preferably, all the intermediate parts 12 are connected to the integral joint 11; the clamping unit 2 is arranged in the joint 11, preferably, one clamping unit 2 is arranged; the joint 11 is used for sealing a cable connecting port H of the equipment; the clamping unit 2 is used for clamping a cable connecting port H of the connecting equipment; the tube core portion 3 detachably supports the main body tube structural unit 1, for example, the cold shrink tube 13, or the intermediate portion 12 and the cold shrink tube body 13.

The clamping unit 2 is arranged in the joint 11 of the main tube structure unit 1, the clamping unit 2 is fixedly bonded with the inner surface of the joint 11 through modified resin, the convex rib 26 of the clamping unit 2 is accommodated in the hollow part of the protruding part 112 on the joint body, the tube core part 3 supports against the main tube structure unit 1, and the sealing layer (not shown in fig. 9, refer to fig. 1 and 2) is circumferentially arranged between the inner surface of the cold shrink tube 13 and the outer surface of the tube core part 3, for example, in the cold shrink tube 13 at the end far away from the middle part 12. Therefore, the cold-shrink sealing element of the embodiment of the invention is formed, the sealing element is clamped and connected with a cable connecting port of a connecting device in a sealing manner, the cold-shrink tube 13 is tightly pressed and attached to the cable, water vapor and dust are prevented from entering the device, the cable connector and the device are prevented from being damaged by the water vapor and the dust, the cold-shrink sealing element is suitable for sealing and protecting various cable connectors in the technical fields of communication, electric power, rail transit, meteorology, intelligent household appliances and the like, and the sealing mode of the cold-shrink sealing element enables the cold-shrink sealing element to be used for the cable connectors with irregular shapes.

Hereinafter, a method of using the cold-shrink seal according to the embodiment of the present invention will be described by way of example, and the cold-shrink seal according to the embodiment of the present invention is not limited to the following specific application examples.

Referring to fig. 10, in a 5G communication device as an example, in general, such a device requires at least two cables (two cables are denoted by K in fig. 10) for connecting optical fibers and cables, and the two cables K need to enter the device through a cable connection port H of the device to be connected to the device M. When the cold-shrink sealing piece P is installed, firstly, a cable K with a cable connector C penetrates through a pipe part pre-expanded by a pipe core part and a clamping unit; then, connecting the cable connector C to the interface T of the equipment M, connecting the clamping unit to the cable connecting port H in a clamping manner, sealing the cable connecting port H by a sealing ring of the joint, and pressing the protruding part of the joint against the outer end face of the cable connecting port H so as to enable the joint to be connected with the cable connecting port H in a sealing manner; and finally, drawing a tube core part formed by the spiral supporting rope, and elastically retracting the cold-shrink tube body circle by circle to compress and attach the cable K, so that the cold-shrink tube body seals the cable. Therefore, the cold-shrink tube body compresses, fits and seals the cable, the sealing layer (not shown in the figure) can enhance the sealing performance of the sealing element to the cable, the joint seals the cable connecting port H to form integral sealing, and external water and dust can be prevented from entering the equipment M to cause damage to the cable connector and the equipment. When the cold-shrink sealing piece is disassembled, the elastic wall of the clamping unit is pressed, the clamping structure is unlocked, the cold-shrink sealing piece provided by the embodiment of the invention can be taken down from the cable connecting port H of the equipment M, and the middle part does not tightly press and attach the cable and can move backwards, so that an operation space is provided for disassembling the cable connector C, and the cold-shrink tube body is not damaged.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A sealing member with a built-in sealing layer is characterized in that,

comprises a main pipe structure unit and a clamping unit;

the main body pipe structure unit comprises an elastic cold shrinkage pipe, a joint for connecting the clamping unit and a middle part for connecting the cold shrinkage pipe and the joint;

a tube core part which can be drawn away is arranged in the cold shrinkage tube and is used for expanding the cold shrinkage tube;

disposing a sealing layer between the tube core and the cold shrink tube;

the clamping unit can be detachably connected with a cable connecting port of equipment;

the clamping unit is at least partially arranged in the joint, and a sealing structure for blocking a cable connecting port of the equipment from being exposed to the outside is arranged at a proper position on the outer surface of the joint.

2. The seal of claim 1, wherein the nipple, intermediate portion, and cold shrink tube are of unitary construction; and/or the presence of a gas in the gas,

the middle part is a cold-shrink material pipe, and the tube core part which can be drawn away extends to the middle part from the cold-shrink pipe; and/or the presence of a gas in the gas,

the middle part is of a flexible special-shaped tube structure, and the middle part is not tightly pressed and attached to the cable in a natural state without being expanded.

3. The seal of claim 1, wherein the fitting includes a fitting body, a sealing ring disposed on an outer surface of a distal end of the fitting body, the sealing ring for sealing a cable connection port of the device, a protrusion disposed on the outer surface of the fitting body proximate the sealing ring, the protrusion for abutting an outer end face of the cable connection port of the device.

4. The seal of claim 3, wherein the fitting body, the seal ring, and the protrusion are of an integrally formed construction; and/or the presence of a gas in the gas,

the sealing ring is obliquely arranged towards the near end of the joint body; and/or the presence of a gas in the gas,

the protruding part protrudes out of the top end of the sealing ring; and/or the presence of a gas in the gas,

the protruding part is of a hollow structure, and the hollow part of the protruding part is communicated with the hollow inner cavity of the joint body.

5. The seal of claim 1, wherein the clamping unit is a hollow structure, and the clamping unit is disposed within the fitting.

6. The seal of claim 5, wherein the fitting and the clamping unit are each of hollow square tubular configuration.

7. The sealing member of claim 1, wherein the snap-fit unit is a press-fit type snap-fit unit structure.

8. The seal of claim 1, wherein the snap-fit unit is enclosed by a plurality of walls, each having a connecting end and a separating end, the plurality of walls being interconnected via the connecting ends; at least two oppositely arranged walls of the plurality of walls are elastic walls, and the far end parts of the elastic walls are provided with buckling structures protruding towards the outer surface of the clamping unit;

preferably, the elastic wall is inclined towards the outer side of the clamping unit;

preferably, a rib is arranged on the outer surface of the clamping unit along the circumferential direction of the clamping unit; the connector comprises a connector body, a sealing ring and a protruding portion, wherein the sealing ring is arranged on the outer surface of the far end of the connector body, the protruding portion is arranged on the outer surface of the connector body and close to the sealing ring, the sealing ring is used for sealing a cable connecting port of the equipment, the protruding portion is used for abutting against the outer end face of the cable connecting port of the equipment, the protruding portion is of a hollow structure, the hollow portion of the protruding portion is communicated with the hollow inner cavity of the connector body, and the convex edge is contained in the hollow portion of the protruding portion.

9. The seal of claim 1, wherein the body tube structure unit comprises one or more cold shrink tubes, the number of the intermediate portions matching that of the cold shrink tubes, each of the cold shrink tubes being connected to one of the joints via one of the intermediate portions, one of the joints, and one of the clamping units.

10. The seal of claim 1, wherein the sealing layer is a mastic sealing layer or a rubber sealing layer.