KR101135823B1 - Connector for branching Cable - Google Patents

Abstract

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a structure and a manufacturing method of a branch branch connection port which can be connected without peeling off an insulation coating and configured to prevent moisture from penetrating into the connection section. It consists of three elements. In addition, the base assembly may be a base of a plastic material having sufficient rigidity and electrical insulation properties, a pair of conductive connection members processed from copper or copper alloy material having excellent electrical conductivity, and rubber having electrical insulation properties and elasticity and flexibility, or Consists of a sealing member made of soft plastic, these three components are characterized by uniting three elements with different characteristics into one through a two-step integral injection molding operation.
Branch line connection port according to the present invention has the advantage that can be easily connected by simply bolting without the cable insulation coating stripping work or waterproofing work such as taping and paraffin coating. In addition, the present invention inserts the conductive connecting member and the sealing member with the base and inserts the conductive connecting member and the sealing member so that when the bolt is tightened, the conductive member is pushed to one side and the sealing member is pushed out to fundamentally block the gap that may occur. It penetrates and prevents leakage or corrosion.

Description

Branch for branching cable {Connector for branching Cable}

The present invention relates to a branch branch connection port which is used for branching one branch line from a main line when working a power supply cable, and in particular, it is possible to work without fear of electric shock even when the main line is not powered off. The present invention relates to a structure and a manufacturing method of a branch line connecting port configured to allow a connection work without peeling off the insulation coating of the cable and to prevent moisture from penetrating into the connection part.

Various methods are used to divert one branch from the main line to power individual loads.

The branching method commonly used in general households is to cut a specific area of the main trunk, and then peel off the insulation coating of both ends of the cut wire and the end of the branch to be connected, and then twist the three strips together to bind them. There is a method of winding with insulating tape after making it. This method has the advantage of being able to work with only a simple tool such as nipper without special connection port, but when external force is applied to the connection part, there is a possibility that the coupling may be loosened or disconnected. This has the inconvenience of suspending the use of other running electrical appliances. In addition, when the method is applied to a lot of moisture or moisture, there is a problem that moisture may penetrate into the insulating tape and cause a short circuit or corrosion of the wire. Also, in case of branching branch line in a power cable with a large allowable current capacity, it is impossible to cut the cable or twist the cable cores of several strands into one, so the applicable fields are limited to low power wiring work in a dry room. There is no choice but to.

The general method used for the simple branching of a branch line from a main trunk composed of a large power supply cable, as shown in FIG. 1, after stripping each section of the main trunk and one end of the branch cable, respectively, A metal C-type crimping clamp is assembled by putting together stripping sections of both cables, and then crimped using a clamping tool, and then winding the connecting section with insulating tape. In addition, in order to prevent the leakage of the tape due to deterioration of the insulating properties and the corrosion of the connection due to moisture infiltration, etc., a method of sealing with a waterproofing with a paraffin or a tube made of lead over the taping section was used. However, this method has a disadvantage in that the workability is very poor due to a complicated work process, and in the case of applying a waterproofing material such as paraffin, it is difficult to secure durability and durability due to deterioration of waterproofing and adhesive properties over time. The method is expensive and requires special work.

Accordingly, the present invention has been conceived to solve the above problems, it is possible to work without the risk of electric shock in the state of disconnecting the power supply of the main trunk in branching one branch line from the main trunk, peeling the insulation coating of the cable The purpose of the present invention is to improve workability by eliminating the preliminary work to be made or the post work to be waterproofed by taping the connection part, while providing a durable and reliable branch line connection port.

In order to achieve the above object, the branch connection port of the present invention is characterized by consisting of three elements, the base assembly, the cover, and the tightening means.

In addition, the base assembly, the fastening hole is formed in the center, the main trunk guide grooves and branch line guide grooves are formed on the left and right sides of the fastening holes, respectively, and orthogonal to the guide grooves, the same separation distance from the center of the fastening holes. A base of a synthetic resin material provided with a conductive connection member insertion groove having; When the base is injection molded, it is inserted into a one-step injection mold to make a one-step integrated molding, and a pair processed with copper or copper alloy material having good electrical conductivity, having main line side teeth and branch line teeth at both ends. An electrically conductive connecting member; After inserting the base in which the integral molding with the conductive connection member is completed into a two-stage injection mold, two-stage molding is performed, and a rubber or soft plastic material having excellent insulation characteristics and elasticity and flexibility is formed, and corresponds to the structure of the base. Forming a fastening hole in the center as possible, and having a main line contact portion and a branch wire inserting portion on the left and right sides of the fastening hole, respectively, and including a sealing member having a through-hole through the teeth at a position corresponding to the tooth portion It is characterized by.

 In addition, the cover is provided with a fastening hole in the center facing the upper surface of the base, characterized in that configured to include a main line guide groove and branch line guide grooves on the left and right sides of the fastening hole, respectively.

In addition, the tightening means is characterized in that it comprises a bolt and nut.

In addition, in the said conductive connection member, the height of the tooth of a main trunk side tooth | gear part is larger than the height of the tooth | gear of a branch line side tooth part, the number of teeth of each tooth formed in each tooth part is at least 3 or more, and the height of an outer tooth is the height of an inner tooth tooth It is characterized in that the higher configuration.

In addition, the cross-sectional shape of the fastening hole of the cover is characterized in that the trapezoidal shape is configured in such a way that the width gradually widens from the bottom to the top.

In addition, the upper surface of the cover is characterized in that the height of the center is composed of a gentle curved surface is gradually lowered toward the outer height.

As described above, the branch connection port according to the present invention can be branched without the risk of leakage even in a state in which the mains supply is not interrupted, and the bolt is fastened without the insulation coating stripping or the waterproofing work such as taping and paraffin coating. The advantage is that you can simply make a branch connection.

In addition, the present invention essentially integrates the conductive connecting member and the sealing member with the base by the integral injection molding method, thereby essentially eliminating the gap between the conductive connecting member, the sealing member and the cover, which may occur while the sealing member is pushed in an unintended direction. By blocking, moisture or moisture penetrates into the charging part, thereby preventing an electric leakage or corrosion.

1 is a diagram showing a branch line connecting structure of the prior art,
2 is a perspective view of a branch line connecting port according to an embodiment of the present invention;
3 is a cross-sectional view of a branch line connecting port according to an embodiment of the present invention;
4 is a perspective view showing the structure of the plane and the back of the base according to an embodiment of the present invention, respectively,
5 is a front view of a conductive connecting member according to an embodiment of the present invention,
6 is a perspective view showing the structure of the plane and the back of the sealing member according to an embodiment of the present invention, respectively,
7 is a perspective view showing the structure of the plane and back of the cover according to an embodiment of the present invention, respectively,
8 is a perspective view showing a branched state to which a branch line connecting connector according to an embodiment of the present invention is applied,
9 is an assembled sectional view showing a branched connection state to which a branch line branch opening according to an embodiment of the present invention is applied;
10 is a flowchart of a manufacturing process of the base assembly according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and how to accomplish them, will become apparent by reference to the embodiments described in detail below with reference to the accompanying drawings.

However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention and those skilled in the art to which the present invention pertains. It is provided to fully inform the scope of the invention, and the invention is defined only by the scope of the claims.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a perspective view schematically showing the outline of the branch line connection port according to the present invention, Figure 3 is a cross-sectional view of the branch line connection port according to an embodiment of the present invention, Figure 4 is an embodiment of the present invention Fig. 5 is a front view of a conductive connection member according to an embodiment of the present invention, and Fig. 6 is a plan view of a sealing member according to an embodiment of the present invention. And FIG. 7 is a perspective view illustrating structures of the rear surface and a rear surface thereof, and FIG. 7 is a perspective view illustrating structures of a plane and a rear surface of the cover according to an embodiment of the present invention, and FIG. 8 is a branch line according to an embodiment of the present invention. 9 is a perspective view illustrating a branched state to which a branch connection port is applied, and FIG. 9 is an assembled cross-sectional view illustrating a branched connection state to which a branch line branching hole according to an embodiment of the present invention is applied, and FIG. 10 is an embodiment of the present invention.According to a manufacturing process flow chart.

As shown in Figs. 2 and 3, the branch branch connector of the present invention comprises three components: the base assembly 10, the cover 400 and the fastening means 500. Base assembly 10 also includes a base 100, a conductive connection member 200 and a closure member 300, which are hermetically coupled to one another through two stages of integral injection molding. Meanwhile, the tightening means includes a bolt 510, a washer 520, and a nut 530.

Then, detailed technical configuration and operation of the main components will be described with reference to FIGS. 4 to 7.

Referring to Figure 4, the base 100 has a fastening hole 110 in the center, and the main trunk guide groove 130 and branch line guide groove 140 on the left and right sides around the fastening hole 110, respectively, And the conductive connecting member insertion grooves 121 and 122 before and after. The cross-sectional shape of the main trunk guide groove 130 and branch guide groove 140 is preferably in the form of an arc so as to evenly support the outside of the cable having a circular cross section.

Further, the radius of the circular arc surface forming the surface of the main trunk guide groove 130 is larger than the radius of the circular arc surface forming the surface of the branch guide grooves, the size of which is not smaller than the radius of the cable cross section of the maximum applicable size It is desirable to. On the other hand, the conductive connection member insertion grooves 121 and 122 are spaced apart from each other in the front and rear by the same distance from the center of the fastening hole 110 and configured to be orthogonal to the main trunk guide groove 130 and the branch guide groove 140, respectively. It is preferable. This is to ensure that the fastening force by the fastening means 500 fastened through the fastening hole 110 located at the center is evenly transmitted to the cable.

In addition, the band guide 170 is formed integrally with the side wall at the center of one side of the upper wall, and the cover guide 160 is formed integrally with the side wall at a position slightly separated from the band guide 170 in front and rear. do. The band guide 170 is linked to the guide jaw 460 provided on one side wall of the cover 400 when the cover 400 covers the cover 400 to prevent the coupling from being misaligned.

In addition, the bottom portion of the base 100 is provided with a bolt head seating groove 150 slightly recessed, the edge of the seating groove 150 is fastened with a nut 530 as the same as the head shape of the bolt to be applied. In the process of the bolt head mounting groove 150 is configured to have a function to prevent the phenomenon that the bolt 510 even if a high fastening force is applied to the bolt 510 by restraining the head of the bolt. For this purpose, the head of the bolt should not be circular, but preferably has a polygonal shape such as hexagon.

On the other hand, the base 100 is excellent in insulation properties because the operator should hold the hand by hand, and is formed of a plastic material with excellent rigidity because it should not be deformed or deteriorated even if left for a long time in a state of high fastening force is applied. It is preferable.

Referring to FIG. 5, the conductive connection member 200 is processed using a copper plate or a copper alloy plate having good electrical conductivity and rigidity. At both ends of the conductive connection member 200, main trunk side teeth 230 and branch line side teeth 240 are provided as shown. The main line side tooth portion 230 and the branch line side tooth portion 240 are each composed of at least three teeth, and the height of the outer teeth 231 and 233 is preferably higher than the height of the inner tooth 232. When the number of teeth is four or more, the height is gradually increased toward the outside from the teeth on the center of the tooth. This is to prevent the connection from being incomplete due to the cable being oriented in either direction as the teeth penetrate the insulation coating of the cable. That is, while the inner tooth 232 penetrates the insulation sheath of the cable, the outer teeth (231, 233) serve to support the cable not to be pushed in either direction, while at the same time penetrates the insulation sheath and drills the core wire inside the cable to make electrical connection. Has the function to perform.

On the other hand, in consideration of the thickness of the cable used as the main trunk is generally thicker than the cable used as the main line, the size of the individual teeth provided in the main trunk toothed portion 230 is provided in the branch line toothed portion 240 It is desirable to be larger than the size of the individual teeth.

The conductive connection member 200 thus formed is firmly coupled to the base 100. If the coupling is not firmly made, the conductive connection member 200 is oriented in one direction during the fastening operation, so that the teeth do not penetrate the insulating coating effectively, and in the severe case, the teeth are pressed laterally and deformation occurs, thereby making electrical connection. It may not be possible to implement the function properly. In addition, water or moisture may penetrate into the gap generated while the conductive connection member 200 is pushed to one side, and a short circuit may occur.

In order to overcome this problem, it is preferable to perform an integrated injection molding operation in the state in which the conductive connection member 200 is inserted into a predetermined position provided in the mold when the base 100 is injection molded.

In addition, the conductive connection members 200 are provided in pairs, and the insertion grooves 121 and 122 are positioned at a distance apart from each other by the same distance from the center of the fastening hole 110 provided in the center of the base 100. It is desirable to allow insertional engagement. The purpose is to secure the reliability of the electrical connection by ensuring that the fastening force generated when the bolt 510 is located at the center is evenly transmitted to each tooth portion 230 and 240, and the connection is made at each two points of the main line and the branch line. There is this.

Referring to FIG. 6, the sealing member 300 is a component provided to prevent water or moisture from flowing into the electrical connection portion and the conductive connection member 200 and causing a short circuit, and is covered by the tightening means 500. When the 400 and the base assembly 10 are coupled, the fastening force of the tightening means 500 is transmitted to the sealing member and has a function of closing all passages to the electrical connection portion and the conductive connection member 200. The material of the sealing member 300 for performing this function is preferably rubber or soft plastic.

In addition, in order to effectively seal the electrical connection portion and the conductive connection member 200 dispersed throughout the base 100, the sealing member 300 is formed on the upper surface of the base 100 is formed integrally with the conductive connection member 200 In order to effectively cover the surroundings of the electrical connection portion and the conductive connection member 200 while covering the entire body, it is preferable to integrally provide a sealing structure suitable for the characteristic of each site.

In more detail, one side of the upper surface of the sealing member 300 is provided with a main line contact portion 330 is tightly coupled while wrapping the lower surface of the main line (C1), the other side of the tubular shape is inserted into the branch line (C2) Branch line inserting portion 340 is provided integrally molded. In addition, a fastening hole 310 for providing a passage through which the bolt 510 penetrates is integrally provided at the center of the sealing member 300.

Meanwhile, a through hole 331 is provided at the center of the main trunk contact portion 330 so that the main trunk side tooth portion 230 of the conductive connection member 200 passes therethrough. In addition, a through hole 341 for allowing the branch line side teeth 240 to penetrate the inner bottom surface of the branch insertion part 340 is provided on the inner bottom surface (not shown) of the branch insertion part 340.

In addition, the main line contact portion 330 is formed in a curved surface of the arc shape so as to wrap around the lower surface of the cable. In addition, one end of the insertion tube 340 is opened to function as the inlet (343) that the branch line is introduced, the other end end 344 is in the form of being blocked. Unlike the main line (C1), since the one end of the branch line (C2) is introduced into the insertion tube 340, the end portion 344 of the inlet (343) is open if the opposite end portion 344 is opened. This is because moisture penetrates and provides a cause of a short circuit.

On the other hand, the lower surface of the sealing member 300 is ribs to remove any gaps that may exist between the upper surface of the base 100 integrally formed with the conductive connecting member 200 and the lower surface of the sealing member 300. The 320 are provided to correspond to the upper surface of the base 100. Among these ribs, ribs surrounding both sides of the conductive connection member 200 are also included.

In addition, after separately forming the sealing member 300, it is not easy to cover the upper surface of the base 100 integrally formed with the conductive connection member 200 and to closely bond the sealing member 300, and the sealing member 300 may be flexible. Since it is formed of a material having the sealing member 300, the ribs 320 provided on the lower surface of each one to fit into the narrow gap is hardly workability. However, when the gap 320 widens the gap so that the ribs can be easily positioned, there is a fine gap even after the sealing member 300 is coupled, and even with this gap, moisture easily penetrates into the interior to prevent leakage. Will be raised.

In addition, when the tight coupling between the conductive connection member 200 and the sealing member 300 is loose, the teeth 230, 240 for the fastening force applied to the fastening means 500 in the process of the fastening work during the branching work to penetrate the insulation coating of the cable As the conductive connection member 200 is pushed to any one side of the conductive connection member 200 while the coupling is loosely transmitted through the conductive connection member 200, a gap is further opened on the other side, and moisture is penetrated into the gap so that a short circuit condition may occur. do.

In order to overcome this problem, when the sealing member 300 is molded, the integrated injection molding operation is performed while the base 100 integrally formed with the conductive connection member 200 is inserted into a predetermined position provided in the mold. It is preferable.

10 is a manufacturing process flow diagram of a base assembly 10 completed through an integrated injection molding process over two stages, which is a key technical idea of the branch branch junction of the present invention.

Referring to FIG. 7, the cover 400 of the branch connection port of the present invention includes a fastening hole 410 at the center, and includes a main line guide groove 430 and a branch guide groove 440 at a lower surface thereof. do.

In addition, it is preferable that the upper surface of the cover 400 forms a smooth curved surface having a height that gradually decreases toward the left and right directions with the center of the fastening hole 410 as a vertex. In addition, the upper surface 450 of the cover 400 is provided with a washer seating groove 451 is dug by the thickness and size of the washer 520 along the upper surface 450. In addition, the fastening hole 410 preferably takes the form of an inverted trapezoid, in which the left and right widths are widened upward from the lower end 411.

Referring to FIG. 9, it is illustrated whether an inverted trapezoid is a preferred shape as a cross-sectional shape of the fastening hole 410 of the cover 400. As shown, the cover 400 may be tilted in one direction and coupled to the base assembly 10 according to the thickness of the main trunk, in which case the central axis of the bolt 510 is the original central axis of the fastening hole 410. If the left and right width are not widened, the bolt 510 is assembled in an inclined state when the bolt 510 is tightened so that the force is not transmitted perpendicularly to the lower surface and the tooth of the cable. Failure to penetrate the insulation sheath of the cable or causing deformation of the teeth, etc., resulting in improper electrical connection. When the thickness of the main line is very thick or thin and the cover 400 is coupled to the base assembly 10 while being inclined severely to the left or the right, the base side fastening hole 110 and the cover side fastening hole 410 are severely displaced and the bolt If the 510 cannot be inserted or is forcibly inserted, the cable is hardly pressed.

 In addition, the guide jaw 460 is formed integrally with the side wall at one side of the lower wall. When the guide jaw 460 is coupled to the base assembly 10, the guide jaw 460 is connected to the cover guide 160 provided on one side wall of the base 100 to prevent the coupling from being misaligned. In addition, the band hanger 470 is integrally formed in a shape protruding from the wall at the center of the same side wall. Hanging the band 370, which is formed integrally with the sealing member 300 to the band hanger 470, even if the bolt 510 and the nut 530 is loosely coupled to prevent the cover 400 from being in place .

In addition, the cover 400 is excellent in insulation properties because the operator must hold the hand by hand, and is formed of a plastic material having excellent rigidity because it should not be deformed or deteriorated even if left for a long time in a state where high fastening force is applied. It is preferable.

On the other hand, the tightening means 500 is composed of a bolt 510, a nut 530 and a washer 520 to ensure a fastening operation simple yet strong fastening strength. It is preferable that the head of the bolt has a polygonal shape such as a hexagon rather than a circular shape in order to prevent the phenomenon of screwing. In addition, the washer 520 is processed to match the radius of curvature of the curved surface formed on the upper surface 450 of the cover, the through hole provided in the center of the washer 520 of the fastening hole 410 of the cover 400 It is preferable to take the form of a long hole extending left and right in the same shape as the top. On the other hand, the length of the bolt 510 preferably has a length enough to fit the main line of the maximum thickness to be applied in the state that the nut 530 is across the end of the bolt 510.

The process of performing the branch connection work using such branch branch connection port is as follows.

First, hold the branch branch connection with one hand and extend it as far as possible so that the main trunk can fit between the cover and the base assembly. Next, the branch line connecting port is inserted at the branch point on the main trunk C1 to allow the main trunk to be seated on the main trunk contact 330. Next, the branch line C2 is inserted into the branch line inserting portion 340. Finally, the nut 530, which is loosely coupled, is fastened strongly and quickly with an impact driver.

At this time, the fastening force generated through the driver is primarily transmitted to the cover 400 and the base assembly 10, the lower surface of the cover 400 presses the upper surface of the insulation coating of the cable and the upper surface of the base assembly 10 The inner surface of the main line contact portion 330 and the branch line inserting portion 340 integrally formed in the sealing member 300 coupled to the base is secured tightly while being in close contact with the insulating coating of the cable, and the base assembly 10 The teeth provided in the main trunk side tooth portion 230 and the branch line side tooth portion 240 of the conductive connecting member 200 coupled to each other penetrate the insulating coating of the main trunk line C1 and the branch line C2. The core wire inside the cable is dug up and electrically energized.

Meanwhile, when the current flowing through the main trunk C1 is classified in more detail as the branch line C2, the current flowing through the main trunk C1 is transmitted through the teeth 231, 232, 233 of the main trunk side tooth 230. The current flows into the conductive connection member made of a material having good electrical conductivity, and this current is transmitted to the branch line C2 through the teeth 241, 242, 243 of the branch line side tooth 240.

The power supply to the load is completed by simply connecting the branch line (C2) drawn from the branch branch connection port in which the fastening is completed to a load requiring electricity such as a light. It is noteworthy that the branch connection process listed above can perform the branching operation without fear of electric shock without disconnecting the electricity supplied to the main trunk for branching, and insulate the main trunk to branch the current. It did not break the sheath. In addition, the taping operation that is commonly performed to prevent a short circuit has become unnecessary.

The state in which the branch connection work described above is completed is shown in FIG. 8, and the thickness of the cable in FIG. 9 is also reduced in the combined state of the cover 400 and the bolt 510 according to the thickness of the main trunk line to be applied. It is shown in the assembly cross-section divided into branches.

C1: main trunk C2: branch line
CL: C type clamp
B: branch branch connection
10: base assembly
100: base 110: fastening hole
121, 122: Insertion groove
130: main trunk guide home 140: branch guide home
150: bolt head seating groove 160: cover guide
170: band guide
200: conductive connection member
230: main trunk side tooth part
231,233: outer tooth 232: inner tooth
240: branch line side tooth part
241, 243: outer tooth 242: inner tooth
300: sealing member 310: fastening hole
320: rib
330: weekly contact
331: through
340: branch line insert
341: through
343: branch inlet 344: terminal end
370: band
400: cover
410: fastener 411: fastener bottom
430: weekly guide home 440: branch guide home
450: cover upper surface 451: washer seating groove
460: Guide Chin 470: Band Hanger
500 tightening means
510: bolt 520: washer
530: Nut

Claims (4)

For branch branch connections, which are applied to branch lines for powering individual loads from the main trunk,
The fastening hole 110 is provided at the center, and main trunk guide grooves 130 and branch line guide grooves 140 are provided at right and left sides of the fastening holes 110, respectively, and are perpendicular to the guide grooves 130 and 140. A base 100 of synthetic resin material having conductive connection member insertion grooves 121 and 122 having the same separation distance from the center of the fastening hole 110,
When the injection molding of the base 100 is inserted into the injection mold of the first stage, a one-step integrated molding is performed, and electrical conductivity having a main line side tooth portion 230 and branch line side tooth portion 240 at both ends is good. At least a pair of conductive connection members 200 processed from a metal material,
The conductive connection member 200 is a thermoplastic material having a two-step molding and excellent insulation properties and flexibility after inserting the base 100 having integrated molding completed in a two-step injection mold, and having a structure of the base 100. A fastening hole 310 is formed in the center so as to correspond to each other, and the main line contact part 330 and the branch wire inserting part 40 are provided on the left and right sides of the fastening hole 310, respectively. Of the sealing member 300 having the through holes 331 and 341 through which the teeth 230 and 240 penetrate at corresponding positions,
Three components,
A base assembly 10 fully coupled through a two-step integral shaping operation;
A cover having a fastening hole 410 at the center facing the upper surface of the base assembly 10 and provided with main trunk guide grooves 430 and branch line guide grooves 440 at left and right sides of the fastening hole 410 ( 400);
Branch branch connection, characterized in that it comprises a fastening means 500 consisting of a bolt 510, a nut 530 and a washer 520 The method of claim 1,
The height of the teeth 231, 232, 233 of the main trunk side teeth 230 is greater than the height of the teeth 241, 242, 243 of the branch side teeth 240, and the number of teeth formed in each of the teeth 230, 240 is at least three, Branch branch connection port characterized in that the height of the outer teeth (231, 233; 241, 243) is configured higher than the height of the inner teeth (232; 242) The method of claim 1,
Branch-side connection port, characterized in that the cross-sectional shape of the cover side fastening hole 410 is configured in the form of an inverted trapezoidal shape gradually widening from the bottom to the top. The method of claim 1,
Branch 450 is the upper surface 450 of the cover 400 is characterized by consisting of a gentle curved surface of the highest height of the center and gradually lower in height toward the exterior

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