Serial tubular bus connector

Abstract

The invention discloses a series tubular bus connector, which comprises a bus connector, interfaces matched with bus connection are arranged in the bus connector, the bus connector is provided with N interfaces, the N interfaces comprise a x interfaces and b y interfaces, N is equal to a + b, x is greater than or equal to 1, and y is greater than or equal to 0; spring contact fingers are arranged in the x interface and the y interface; the T shape can be used for the connection between the main bus and the branch bus, so that the through part and the vertical part at the two ends have different diameters, the large-diameter part can be used for the main bus, and the through part and the vertical part can also adopt an equal-diameter design for the separation of the incoming line cabinet. In the linear connector, the bus connector is used for connecting the main buses. The spring contact finger has elasticity, and the spring contact finger tightly holds the main bus or the branch bus to form reliable electrical connection.

Description

Technical Field

[0001] This invention belongs to the field of connector technology, specifically relating to a series of tubular busbar connectors. Background Technology

[0002] Busbar systems are used in power distribution, and the adoption of high-voltage busbar systems and advanced insulation materials significantly improves power transmission efficiency and reliability. With the rapid development of industrial automation, data centers, rail transportation, and other fields, the application scenarios of busbar systems are constantly expanding, and the performance requirements for busbar connectors are becoming increasingly stringent.

[0003] The existing main busbars and branch busbars all use conduit busbars, whose connection structure is complex, requiring machining and bolt tightening. Welding or flange bolt connections are commonly used. While welding provides reliable connections, it presents challenges such as difficult on-site construction, high process requirements, inconvenient disassembly, and difficulties in future maintenance or capacity expansion. Furthermore, due to thermal expansion and contraction of the bolt metal or vibration, the contact resistance at the connection point can easily increase, leading to localized overheating and affecting power supply reliability. Poor contact can directly cause excessive temperature rise at the connection point, becoming a potential hazard to the safe operation of the system. Summary of the Invention

[0004] The purpose of this invention is to provide a series of tubular bus connectors to solve the problems of reliable and stable bus connection and power supply in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A series of tubular bus connectors includes a bus connector with an interface for matching bus connection. The bus connector has N interfaces, of which a are x interfaces and b are y interfaces, where N = a + b, and x ≥ 1, y ≥ 0. Spring contact fingers are installed in both the x interfaces and the y interfaces.

[0006] Preferably, in the bus connector, when x=1 and y=0, the bus connector forms an "I"-shaped connector; Preferably, in the bus connector, when x=1 and y=1, the bus connector forms a "T" shaped connector; Preferably, the busbar is divided into a main busbar and a branch busbar, and both the main busbar and the branch busbar have a hollow structure in the middle.

[0007] Preferably, in the "T"-shaped connector, the outer wall of the x-interface has at least one first threaded hole, and the outer wall of the y-interface has at least one second threaded hole, with the first threaded hole and the second threaded hole being disposed on the same reference plane.

[0008] Preferably, in the "I"-shaped connector, the outer wall of the x-interface has at least two first threaded holes.

[0009] Preferably, the outer wall of the main busbar and the branch busbar is provided with a slot, which is used to correspond to the lower part of the first threaded hole or the second threaded hole. Both the first threaded hole and the second threaded hole can be used to install screws, which are stuck in the slot. In the "I"-shaped connector, there are at least two slots on the outer wall of the main busbar; In a T-shaped connector, at least one of the slots on the outer wall of the main busbar and the branch busbar is present.

[0010] Preferably, the x-interface has first grooves installed at both ends; In the "I"-shaped connector, there are at least two first grooves at both ends of the x-interface; In a T-shaped connector, there is at least one first groove at each end of the x-interface.

[0011] Preferably, the Y-interface has a mounting hole for installing a branch busbar, the mounting hole does not penetrate into the X-interface, a second groove is provided below the second threaded hole, and in the "T"-shaped connector, there are at least two second grooves, and the spring contact finger is installed in the first groove and the second groove.

[0012] Preferably, in the "T"-shaped connector, the outer diameter of the x-interface is designated as D1 and the inner diameter as D2; the outer diameter of the y-interface is designated as D4 and the inner diameter as D3. When D1=D4, then D2=D3; this is used to apply to incoming line cabinets.

[0013] When D1 > D4, then D2 > D3; this applies to outgoing line cabinets.

[0014] Preferably, in the "T"-shaped connector, the distance between the two second grooves represents C, the groove width of the second groove represents B, the distance between the outermost second groove and the outer end of the y interface represents A, and the two ends of the second groove are provided with included angle α, and rounded corners R are machined on both sides of included angle α. Preferably, in the "I"-shaped connector, the distance between the two first grooves represents C, the groove width of the first groove represents B, the distance between the outermost first groove and the outer end of the x interface represents A, and the two ends of the first groove are provided with included angle α, and rounded corners R are machined on both sides of included angle α.

[0015] The technical solution of this invention has the following beneficial effects: 1. The "T"-shaped connector can be used for connections between main busbars and branch busbars. Therefore, the through-ends can have different diameters than the vertical sections; the larger diameter is used for the main busbar. Alternatively, the through-ends and vertical sections can have the same diameter for use in incoming line cabinets. In the "I"-shaped connector, the busbar connector is used for connections between main busbars. The "I"-shaped structure ensures a single mating direction (straight-line insertion) between the busbar connector and the main busbar, eliminating the need for complex angle adjustments and significantly reducing installation time.

[0016] 2. The inner diameter of the spring contact finger is smaller than the outer diameter of the main busbar or branch busbar. After the main busbar or branch busbar enters the cavity and passes through the spring contact finger, the spring contact finger, due to its elasticity, holds tightly onto the main busbar or branch busbar, forming a reliable electrical connection. Because the spring contact finger is installed in specific grooves (first groove and second groove), this electrical connection will not change even if the main busbar or branch busbar moves or the connector itself moves as a whole. During both installation and disassembly, the spring contact finger improves the stability of the busbar electrical connection and facilitates the connection and disassembly of the busbar. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0018] Figure 1 This is a diagram showing the installation state of the "T"-shaped connector of the present invention.

[0019] Figure 2 This is a schematic diagram of the "T"-shaped connector structure of the present invention.

[0020] Figure 3 This is a diagram of the internal structure of the "T"-shaped connector of the present invention.

[0021] Figure 4 This is a diagram of the internal mounting structure of the "T"-shaped connector of the present invention.

[0022] Figure 5 This is a diagram showing the installation state of the "I"-shaped connector of the present invention.

[0023] Figure 6 This is a schematic diagram of the "I"-shaped connector structure of the present invention.

[0024] Figure 7 This is a schematic diagram of the internal structure of the "I"-shaped connector of the present invention.

[0025] Figure 8 This is a schematic diagram of the internal mounting structure of the "I"-shaped connector of the present invention.

[0026] Figure 9This is a schematic diagram of the busbar structure of the present invention.

[0027] Reference numerals: 101, first groove; 102, first threaded hole; 201, mounting hole; 202, second groove; 203, second threaded hole; 30, spring contact finger; 40, main busbar; 401, slot; 50, branch busbar; 60, screw. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0029] Example 1: Reference Figures 1-9 , A series of tubular bus connectors includes a bus connector with an interface for matching bus connection. The bus connector has N interfaces, of which a are x interfaces and b are y interfaces, where N = a + b, and x ≥ 1, y ≥ 0. In the bus connector, when x=1 and y=0, the bus connector forms a "I"-shaped connector; In the bus connector, when x=1 and y=1, the bus connector forms a "T" shaped connector; In the above implementation scheme, both the "I"-shaped connector and the "T"-shaped connector of this product are used for connection between tubular busbars. Both the "I"-shaped connector and the "T"-shaped connector employ a metal casting process to construct a thin-walled connection structure with an outer "I"-shaped cavity and an outer intersecting "T"-shaped cavity. Their diameter is selected according to the current carrying capacity. The "I"-shaped connector can be used for connection between main busbars. The "T" shape can be used for connections between main busbars and branch busbars. Therefore, the through-ends can have different diameters than the vertical sections; the larger diameter is used for the main busbar. Alternatively, the through-ends and vertical sections can have the same diameter for use in incoming line cabinets. This involves using a "T" connector to leave the x-interface in the original electrical compartment, while the y-interface passes through the partition between the two compartments to enter another electrical compartment (either above or below the original compartment), thus electrically connecting the two compartments. The busbar is inserted into either the x-interface or y-interface, making the overall connection and installation simple and allowing for easy adjustment of the insertion distance.

[0030] In this embodiment, optionally, since N=a+b and x≥1, y≥0, when x=2, y=0, it can be represented as two x interfaces combined and spliced ​​together. The purpose is to increase the length of the x interface. When x=1, y=2, if the length of the x interface is long enough, its Y interface can be vertically distributed below the x interface.

[0031] In this embodiment, optionally, in the "T"-shaped connector, one end of the x interface is closed and extended, and the Y interface is connected to the x interface, so that the structure becomes L-shaped.

[0032] Preferably, the busbar is divided into a main busbar 40 and a branch busbar 50, and both the main busbar 40 and the branch busbar 50 have a hollow structure in the middle; In the preferred embodiment, in the "T"-shaped connector, the x-interface is used for connecting the main bus 40, and the y-interface is used for connecting the branch bus 50. In high-frequency or high-current scenarios, current tends to concentrate on the conductor surface (skin effect). The hollow structure of the main bus 40 and branch bus 50 increases the surface area, making the current distribution more uniform, reducing the risk of local overheating, and thus improving the overall current carrying capacity. The hollow interior can form a natural convection channel, accelerating heat dissipation; it can also reduce the amount of conductive materials such as copper or aluminum used.

[0033] In the "I"-shaped connector, the x-interface is used for connecting main bus 40 to main bus 40. The "I"-shaped structure ensures a single mating direction (straight-line insertion) between the x-interface and main bus 40, eliminating the need for complex angle adjustments and significantly reducing installation time; (Reference) Figure 8 When the "I"-shaped connector is used as a connector, the two main busbars 40 are inserted into the two ends of the x interface respectively to complete the connection of the x interface; Preferred reference Figures 1-4 In the “T” type connector, the outer wall of the x interface has at least one first threaded hole 102, and the outer wall of the y interface has at least one second threaded hole 203. The first threaded hole 102 and the second threaded hole 203 are set on the same reference plane.

[0034] In the preferred embodiment, when used as a "T"-shaped connector, the main busbar 40 and the branch busbar 50 are inserted into the x-interface and y-interface respectively, adjusted to a suitable installation distance, and a bolt is rotated and installed in the first threaded hole 102 and the second threaded hole 203 respectively. By rotating and tightening the bolts, the main busbar 40 and the branch busbar 50 on the x-interface and y-interface are pressed together. The bolt locking structure provides high-strength mechanical fixation, effectively resisting displacement caused by vibration, impact or thermal expansion and contraction, and preventing the busbars from loosening or falling off. The insertion installation combined with the positioning connection method of the threaded holes greatly improves the convenience of installation. Among them Figure 3In the process, the number of the first threaded holes 102 needs to be set according to the length E of the x interface; the number of the second threaded holes 203 needs to be set according to the length L.

[0035] Preferred reference Figures 5-8 In the "I" type connector, at least two first threaded holes 102 are opened on the outer wall of the x interface.

[0036] In a preferred embodiment, in the "I"-shaped connector: the two first threaded holes 102 are symmetrical about the x interface, and two main busbars 40 are installed on the x interface, each main busbar 40 taking half of the area, and the two main busbars 40 are fixed by tightening the bolts in the first threaded holes 102. The x-interface of the "I"-shaped connector is wider than that of the "T"-shaped connector. This is to ensure that the x-interface of the "I"-shaped connector has sufficient length to simultaneously insert two main busbars 40. As the x-interface length increases, several more can be added to the two first threaded holes 102 to improve stability.

[0037] Preferred reference Figures 1-9 The outer walls of the main busbar 40 and the branch busbar 50 are provided with slots 401. The slots 401 are used to correspond to the first threaded hole 102 or the second threaded hole 203. Screws 60 can be installed on both the first threaded hole 102 and the second threaded hole 203. The screws 60 are stuck in the slots 401. In the above scheme, the slot 401 is preset on the outer wall of the main busbar 40 and the branch busbar 50. The purpose is to correspond to and adapt to the first threaded hole 102 and the second threaded hole 203. The preset slot 401 means that the connection position of the busbar is kept constant. In this way, when installing the busbar, there is no need to adjust and consider the connection insertion depth of the busbar. It is only necessary to align the slot 401 with the first threaded hole 102 and the second threaded hole 203. The connection of the busbar is completed by rotating the connecting screw 60 into the slot 401. Since the slot 401 is elliptical in shape and is restricted by the connection of the screw 60, the busbar can move left and right within the range of the slot 401. Unlike bolt connections, the screw 60 here does not need to be tightened. It is only necessary to ensure that the screw 60 is within the range of the slot 401 to ensure that the busbar has a certain range of movement. The main busbar 40 with a certain automatic extension and retraction margin is connected to the branch busbar 50. The stability of the busbar is achieved by the spring contact finger 30. In this way, reliable current conduction is achieved without bolt tightening. In the "I" type connector, there are at least two slots 401 on the outer wall of the main bus 40; the two slots 401 are to be able to install the main bus 40 at both ends at the same time; the specific number of slots 401 is determined according to the length of the x interface. In a T-shaped connector, there must be at least one slot 401 on the outer wall of the main busbar 40 and the branch busbar 50. Only one slot 401 is needed to connect one main busbar 40. It should be noted that, regardless of whether it is a "I"-shaped connector or a "T"-shaped connector, the cavity on the connector is 1-2mm larger than the main busbar or branch busbar. This is to ensure that the busbar can be smoothly inserted into the X-interface or Y-interface. Since the X-interface or Y-interface is a cylindrical structure, the first threaded hole 102 and the second threaded hole 203 can be machined in an array. Similarly, the outer wall of the busbar also needs to have corresponding slots 401 on the array. The number mentioned above as "at least" can be set in a circumferential array or distributed at equal intervals in a straight line. The specific machining needs to be based on the actual application, and it is also necessary to ensure that the number of threaded holes and slots 401 correspond to each other.

[0038] Preferably, the x-interface has first grooves 101 installed at both ends; in the "I"-shaped connector, there are at least two first grooves 101 at both ends of the x-interface; the first grooves 101 are used to install spring contact fingers 30.

[0039] In the above scheme, in the "I"-shaped connector: since two main busbars 40 need to be installed at the same time, spring contact fingers 30 (a total of four) are installed in the symmetrically arranged first groove 101 to stabilize the busbars at both ends of the x interface.

[0040] In the "T" connector, there is at least one first groove 101 at each end of the x-interface. Two spring contacts 30 are installed in the symmetrically arranged first grooves 101 to stabilize one busbar within the x-interface.

[0041] Preferred reference Figure 3 and Figure 4 The Y-interface has a mounting hole 201 for installing the branch bus 50. The mounting hole 201 does not penetrate into the X-interface. A second groove 202 is provided below the second threaded hole 203. In the "T"-shaped connector, there are at least two second grooves 202.

[0042] In a preferred embodiment, in the "T"-shaped connector: at least two second grooves 202 are provided to install two spring contacts 30. Because the branch bus 50 inserted into the Y-interface is vertically downward and the insertion depth is affected by the mounting hole 201, the branch bus 50 may slide down due to gravity. At least two spring contacts 30 can increase the contact friction between the branch bus 50 and the spring contacts 30, preventing the branch bus 50 from becoming loose during electrical connection and improving the stability of the electrical connection.

[0043] Spring contacts 30 are installed in the first groove 101 and the second groove 202. In the application of the spring contacts 30: the spring contacts 30 are pre-installed in the grooves, and the inner diameter of the spring contacts 30 is smaller than the outer diameter of the main busbar 40 or the branch busbar 50. After the main busbar 40 or the branch busbar 50 enters the cavity and passes through the spring contacts 30, due to the elasticity of the spring contacts 30, the spring contacts 30 hold tightly onto the main busbar 40 or the branch busbar 50, forming a reliable electrical connection. Because the spring contacts 30 are installed in specific grooves (first groove 101 and second groove 202), this electrical connection will not change even if the main busbar 40, the branch busbar 50, or the connector itself moves as a whole. To ensure that the offset of the connector installation position is within a controllable range, the slot 401 on the main busbar 40 or branch busbar 50 is aligned with the first threaded hole 102 or the second threaded hole 203. Then, a screw 60 is rotated into the threaded hole, so that the screw 60 is positioned on the slot 401, thereby fixing the main busbar 40 or branch busbar 50. This achieves reliable current conduction without bolt tightening. Based on the mature application of the spring contact finger 30 in electrical products, such as disconnect switches, its reliability in current conduction has been proven by numerous engineering applications. By adjusting the material and cross-section, as well as increasing or decreasing the number used, it can cover all current levels currently used in engineering applications. Since this connector is a pure conductor and has no insulation issues, it can be used for various voltage levels. Considering the characteristics of its structure, it is more suitable for the internal metal-enclosed switchgear of various transformer and distribution systems in the medium-voltage field. The first groove 101 and the second groove 202 are used to stabilize the connection of the spring contact finger 30. To ensure the product's economic efficiency, it needs to be designed meticulously. First, the material, diameter, and width of the spring contact finger 30 to be used should be determined according to the different current levels.

[0044] Preferred test Figure 3 In the "T" type connector, the outer diameter of the x interface is marked as D1 and the inner diameter as D2; the outer diameter of the y interface is marked as D4 and the inner diameter as D3. In the preferred embodiment: when D1=D4, then D2=D3; this is applicable to incoming line cabinets. D1 is determined based on the rated current of the main busbar, and D4 is determined based on the current of the branch busbar. The current of the main busbar in the incoming line cabinet is equal to the current of the branch busbar, therefore D1=D4. When D1>D4, then D2>D3; this is applicable to outgoing line cabinets; according to actual usage needs, connectors of different diameters are set to correspond to different specifications of the main busbar 40 and branch busbar 50. In summary, regardless of the current magnitude (i.e., the diameter of the connecting busbar corresponds to the diameter of the x-interface or y-interface), or the change in the voltage level, as long as the design structure is the same or similar, it is within the protection scope of this patent. For example, closing one end of the T-type to make the structure L-type (or elbow type) is also a variation of this design structure, or adding a boss between the two busbars of a type, etc.

[0045] Preferred reference Figure 3 In a "T"-shaped connector, the distance between the two second grooves 202 represents C, the width of the second groove 202 represents B, the distance between the outermost second groove 202 and the outer end of the y-interface represents A, and the two ends of the second groove 202 are provided with an included angle α, with rounded corners R machined on both sides of the included angle α. In a "I"-shaped connector, the distance between the two first grooves 101 represents C, the width of the first groove 101 represents B, the distance between the outermost first groove 101 and the outer end of the x-interface represents A, the two ends of the first groove 101 are provided with an included angle α, and rounded corners R machined on both sides of the included angle α.

[0046] In the preferred embodiment, whether in a "T"-shaped connector or a "I"-shaped connector, A, B, and C are the groove width, edge distance, and spacing suitable for designing the spring contact finger 30. α is the included angle between the two sides of the bottom of the groove. This design has better flow guiding capability than a single flat bottom. The appropriate included angle is more suitable for the installation and flow guiding of the spring contact finger 30. R is the rounded corner of the joint between the surfaces inside the groove, which can reduce the difficulty of manufacturing. The groove adopts a pre-cast and then machined process to ensure the smoothness of the groove to maximize the flow guiding needs. The position of M in the figure is determined according to the positioning requirements and the size of the opening.

[0047] In summary, this invention features a simple structure, reliable conductivity, and convenient installation. The conductor connection no longer requires fastening bolts, and the use of flexible spring contacts 30 avoids cumbersome connections and provides reliable current conduction, while also preventing mechanical damage caused by thermal deformation of the long busbar. The overall length dimensions L, F, and D1 all affect cost; choosing the smallest possible dimensions can reduce material costs.

[0048] The specific implementation process of this invention is as follows: The spring contact finger 30 is pre-installed in the groove. The inner diameter of the spring contact finger 30 is smaller than the outer diameter of the main busbar 40 or the branch busbar 50. After the main busbar 40 or the branch busbar 50 enters the cavity and passes through the spring contact finger 30, the spring contact finger 30 is elastic and thus holds tightly to the main busbar 40 or the branch busbar 50, forming a reliable electrical connection. This installation method covers both "T" type connectors and "I" type connectors. In both "T" type connectors and "I" type connectors, the variables are the spring contact finger 30, the number of threaded holes, and the diameter of the connector holes.

[0049] The above embodiments are merely exemplary models of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Various modifications or equivalent substitutions can be made to the present invention within its spirit and scope of protection. Such modifications or equivalent substitutions should also be considered to fall within the scope of protection of the present invention.

[0050] In the description of this invention, it should be noted that the terms "inner," "front," "rear," "left," and "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the appended circle, or the orientation or positional relationship in which the product of this invention is conventionally placed during use. They are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, these terms indicating orientation or positional relationships should not be construed as limitations on the invention.

[0051] In the description of this invention, it should be further noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, these terms can refer to a fixed connection, a detachable connection, or an integral connection between elements; they can also refer to a mechanical connection or an electrical connection; or they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in this invention according to the specific circumstances.

Claims

1. A series tubular bus connector characterized by, Includes a bus connector, which has an interface for matching bus connection. The bus connector has N interfaces, of which a are x interfaces and b are y interfaces, where N = a + b, and x ≥ 1, y ≥ 0. Spring-loaded contact fingers (30) are installed in both the x-interface and the y-interface.

2. A series tubular bus connector according to claim 1, wherein: In a bus connector, when x=1 and y=0, the bus connector forms a "I"-shaped connector.

3. A series tubular bus connector according to claim 1, wherein: In a bus connector, when x=1 and y=1, the bus connector forms a "T" shaped connector.

4. A series of tubular busbar connectors according to claim 2 or 3, characterized in that: The busbar is divided into a main busbar (40) and a branch busbar (50), and both the main busbar (40) and the branch busbar (50) have a hollow structure in the middle.

5. A series of tubular busbar connectors according to claim 3, characterized in that: In the "T" type connector, the outer wall of the x interface has at least one first threaded hole (102), and the outer wall of the y interface has at least one second threaded hole (203). The first threaded hole (102) and the second threaded hole (203) are set on the same reference plane.

6. A series of tubular busbar connectors according to claim 2, characterized in that: In the "I" type connector, at least two first threaded holes (102) are formed on the outer wall of the x interface.

7. A series of tubular busbar connectors according to claim 4, characterized in that: The outer walls of the main busbar (40) and the branch busbar (50) are provided with slots (401), which are used to correspond to the first threaded hole (102) or the second threaded hole (203) below. Screws (60) can be installed on both the first threaded hole (102) and the second threaded hole (203), and the screws (60) are stuck in the slots (401). In the "I"-shaped connector, there are at least two slots (401) on the outer wall of the main bus (40); In the "T"-shaped connector, at least one of the slots (401) on the outer wall of the main bus (40) and the branch bus (50) is present.

8. A series of tubular busbar connectors according to claim 7, characterized in that: The x interface has a first groove (101) installed at both ends. In the "I"-shaped connector, there are at least two first grooves (101) at both ends of the x-interface; In the "T" connector, there is at least one first groove (101) at both ends of the x interface.

9. A series of tubular busbar connectors according to claim 8, characterized in that: The y-interface is provided with a mounting hole (201) for installing a branch bus (50). The mounting hole (201) does not penetrate into the x-interface. A second groove (202) is provided below the second threaded hole (203). In the "T"-shaped connector, there are at least two second grooves (202). The spring contact finger (30) is installed in the first groove (101) and the second groove (202).

10. A series of tubular busbar connectors according to claim 3, characterized in that: In the "T" shaped connector, the outer diameter of the x-interface is designated as D1 and the inner diameter as D2; the outer diameter of the y-interface is designated as D4 and the inner diameter as D3. When D1=D4, then D2=D3; this is applicable to incoming line cabinets. When D1 > D4, then D2 > D3; applicable to outgoing line cabinets; In the "T" shaped connector, the distance between the two second grooves (202) represents C, the groove width of the second groove (202) represents B, the distance between the outermost second groove (202) and the outer end of the y interface represents A, and the two ends of the second groove (202) are provided with included angle α, and rounded corners R are machined on both sides of included angle α; In the "I"-shaped connector, the distance between the two first grooves (101) represents C, the groove width of the first groove (101) represents B, the distance between the outermost first groove (101) and the outer end of the x interface represents A, and the two ends of the first groove (101) are provided with included angle a, and rounded corners R are processed on both sides of included angle a.

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