Invisible bidirectional expansion connecting piece for plates

Abstract

An invisible bidirectional expansion connecting piece for plates comprises a connecting screw rod and an expansion connecting piece body arranged outside the connecting screw rod in a sleeving mode, the expansion connecting piece body comprises a first connecting piece body and a second connecting piece body, connecting grooves are formed in the opposite faces of the first connecting piece body and the second connecting piece body in an inward concave mode respectively, and the two connecting grooves are in butt joint to define a hollow cylinder. An upper expansion area and a lower expansion area are arranged at the upper end and the lower end of the expansion connecting piece respectively, an inner threaded hole is formed in the inner wall of a cylinder body of the lower expansion area, and the connecting screw rod is connected into the inner threaded hole in a threaded mode. An upper threaded column and a lower threaded column are arranged on the outer side of the upper expansion area and the outer side of the lower expansion area respectively, and the thread turning direction of the lower threaded column is opposite to that of the lower threaded column. The connecting piece has the advantages that the expansion areas at the upper end and the lower end are arranged, the rotating directions of the two outer side threaded columns are opposite, two-way two-end expansion connection of the connecting piece is achieved, the situation that a traditional eccentric connecting piece shakes due to a gap between the connecting piece and a plate is avoided, and the stability and firmness of connection are improved.

Description

Technical Field

[0001] This utility model relates to a sheet metal connector, specifically a sheet metal invisible bidirectional expansion connector. Background Technology

[0002] In the panel furniture connection components on the market, eccentric connectors are commonly used to connect and fix adjacent panels. Traditional eccentric connectors include an eccentric wheel, a connecting rod, and a pre-embedded nut, commonly known as a "three-in-one connector." This eccentric connector mainly utilizes the arc of the bottom torsional bend of the eccentric wheel, which deviates from the center of the circle. By rotating the cross-head screw slot on the eccentric wheel with a screwdriver, the connecting rod is passively pulled towards the center of the eccentric wheel along the arc, thereby shortening the distance between the connecting rod, the eccentric wheel, and the pre-embedded nut, achieving a tight connection between adjacent panels.

[0003] Traditional eccentric connectors, after the eccentric wheel is locked, have a certain gap between the connecting rod and the inner hole of the connecting plate containing the eccentric wheel. This gap makes the connecting plate prone to wobbling, especially over long-term use. This wobbling gradually intensifies, leading to loosening of the connection and affecting the overall stability and lifespan of the furniture, posing a safety hazard. Secondly, traditional eccentric connectors have a complex structure, high manufacturing cost, and numerous parts. Their installation is complex and time-consuming; even slight deviations can easily lead to connection failure or insufficient connection strength. Utility Model Content

[0004] The purpose of this utility model is to overcome the shortcomings of existing technologies and provide a simple structure, low manufacturing cost, bidirectional expansion joint with stable and firm connection, convenient installation and high operation efficiency, strong deformation capability and wide applicability, invisible connection, and improved appearance of a sheet metal invisible bidirectional expansion joint.

[0005] The purpose of this utility model is achieved in the following way: a plate invisible bidirectional expansion connector, including a connecting screw and an expansion connector fitted outside the connecting screw, the expansion connector including a first connector and a second connector, the opposite surfaces of the first connector and the second connector are respectively recessed with connecting grooves, the two connecting grooves are joined together to form a hollow cylinder, and the connecting screw is screwed into the cylinder.

[0006] The expansion connector has an upper expansion zone and a lower expansion zone at its upper and lower ends, respectively. The inner wall of the cylinder in the lower expansion zone has an internal threaded hole, and the connecting screw is screwed into the internal threaded hole.

[0007] The upper expansion zone and the lower expansion zone are respectively provided with an upper threaded post and a lower threaded post on their outer sides, and the threads of the lower threaded post and the lower threaded post have opposite directions.

[0008] The first connector has a recessed groove on its outer side wall, and the second connector has a protruding elastic buckle on its outer side wall. The elastic buckle is fastened into the groove, thus fixing the first connector and the second connector together.

[0009] The upper expansion zone is provided with an upper longitudinal groove running through it axially.

[0010] The lower expansion zone is provided with a lower longitudinal slot running through it along the axial direction.

[0011] A deformation groove is provided above the lower expansion zone, the deformation groove penetrates the lower expansion zone and communicates with the cylinder; the outer cross section of the deformation groove is a concave inclined surface.

[0012] Several positioning buckles are distributed along the circumference of the outer side of the upper expansion zone.

[0013] The beneficial effects of this utility model are: 1. Simple structure, low manufacturing cost, and improved market competitiveness. 2. Simplified structure, significantly reduced number of parts, improved installation efficiency, and convenient and easy operation. 3. The expansion zones at the upper and lower ends are set, and the two outer threaded columns rotate in opposite directions, enabling bidirectional expansion connection of the connector. This avoids the shaking caused by the gap between the connector and the board, thus improving the stability and firmness of the connection and achieving ideal connection strength. 4. The deformation groove design further enhances the deformation range of the lower expansion zone, enabling it to adapt to the connection of boards with different hole diameters or thicknesses, improving the adaptability of the connector. 5. The positioning buckle is set to prevent rotation and provide additional connection friction, enhancing the connection strength and ensuring smooth installation of the connector. 6. The expansion connector is embedded in the board as a whole, achieving an invisible connection and enhancing the aesthetic appearance of the furniture. Attached Figure Description

[0014] Figure 1 This is a rendering of the final assembly of this utility model.

[0015] Figure 2 This is a cross-sectional view of the expansion connector in this utility model.

[0016] Figure 3-4 This is a structural assembly drawing of the expansion connector in this utility model.

[0017] Figure 5 This is a schematic diagram of the connecting screw in this utility model. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to the accompanying drawings. A concealed bidirectional expansion connector for sheet metal includes a connecting screw 1 and an expansion connector 2 fitted outside the connecting screw 1. The expansion connector 2 includes a first connector 21 and a second connector 22. The opposing surfaces of the first connector 21 and the second connector 22 are respectively recessed with connecting grooves 3. The two connecting grooves 3 are joined together to form a hollow cylinder. The connecting screw 1 is screwed into the cylinder.

[0019] The upper end and lower end of the expansion connector 2 are respectively provided with an upper expansion area 4 and a lower expansion area 5. The inner wall of the cylinder of the lower expansion area 5 is provided with an internal threaded hole 52, and the connecting screw 1 is screwed into the internal threaded hole 52.

[0020] The outer sides of the upper expansion zone 4 and the lower expansion zone 5 are respectively provided with an upper threaded post 41 and a lower threaded post 51, and the thread direction of the lower threaded post 51 is opposite to that of the lower threaded post 51.

[0021] The first connector 21 has a recessed groove 211 on its outer side wall, and the second connector 22 has a protruding elastic buckle 221 on its outer side wall. The elastic buckle 221 is fastened in the groove 211, thus fixing the first connector 21 and the second connector 22 into one piece.

[0022] The upper expansion zone 4 is provided with an upper longitudinal groove 42 extending through it along the axial direction.

[0023] The lower expansion zone 5 is provided with a lower longitudinal groove 53 extending through it along the axial direction.

[0024] A deformation groove 6 is provided above the lower expansion zone 5. The deformation groove 6 penetrates the lower expansion zone 5 and communicates with the cylinder. The outer cross section of the deformation groove 6 is a concave inclined surface.

[0025] Several positioning buckles 7 are distributed along the circumference of the outer side of the upper expansion zone 4.

[0026] Working Principle: Unlike traditional three-in-one connectors, the expansion connector in this case includes a first connector and a second connector. The opposing surfaces of the two connectors are recessed to form connecting grooves. They are assembled using snap-fit ​​grooves and elastic buckles on their opposite outer sides, forming a hollow cylinder. The two connectors are then joined together to form the expansion connector. This snap-fit ​​method simplifies the assembly process, reduces the number of parts, improves installation efficiency, and makes operation convenient and easy. The connecting screw is then inserted into the connecting groove.

[0027] It should be noted that the expansion connector is provided with an upper expansion zone and a lower expansion zone, which respectively contact the upper and lower ends of the hole wall of the pre-embedded hole in the plate. At the same time, an upper threaded post is provided on the outer side of the upper expansion zone, and a lower threaded post is provided on the outer side of the lower expansion zone, with the upper and lower threaded posts having opposite directions of rotation.

[0028] When the user begins the connection and installation, they use a screwdriver or other tools to rotate the connecting screw, which is then screwed inward along the internal threaded hole in the lower expansion zone. Because the two threads rotate in opposite directions, when the connecting screw is tightened, the upper and lower expansion zones experience opposite tensile or thrust forces, causing the connector to expand outward. The upper longitudinal groove in the upper expansion zone and the lower longitudinal groove in the lower expansion zone allow the connector to elastically deform under pressure in the expansion zones, enabling the upper and lower threaded posts to smoothly embed into the hole walls of the sheet metal, creating a bidirectional, double-ended expansion fixation effect. This bidirectional, double-ended expansion zone design avoids the wobbling caused by gaps between the connector and the sheet metal, as is common in traditional eccentric connectors, thus improving the stability and firmness of the connection.

[0029] Secondly, a deformation groove is also provided above the lower expansion zone. The deformation groove runs through the lower expansion zone and is connected to the cylinder. Its outer cross section is a concave inclined surface. The design of the deformation groove further enhances the deformation range of the lower expansion zone, enabling this expansion connector to adapt to the connection of plates with different hole diameters or thicknesses, disperse the stress distribution of the connector, improve the adaptability of the connector, and reduce the risk of damage to the plate.

[0030] After the expansion connector is fully embedded and installed, in order to enhance the connection strength, several positioning buckles are distributed along the circumference on the outer side of the upper expansion area. The positioning buckles provide additional anti-rotation and anti-friction, effectively preventing the expansion connector from rotating during the tightening process, and further enhancing the firmness and reliability of the connection.

[0031] In addition, after the expansion connector is installed, the connecting screw is embedded in the expansion connector, and the expansion connector body is also embedded in the board, achieving an invisible connection effect. Compared with the exposed screw heads of traditional eccentric connectors, this improves the overall appearance of the furniture and enhances the user's visual experience, so it can be widely promoted.

[0032] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A concealed bidirectional expansion connector for sheet metal, comprising a connecting screw (1) and an expansion connector (2) fitted outside the connecting screw (1), characterized in that: The expansion connector (2) includes a first connector (21) and a second connector (22). The first connector (21) and the second connector (22) have concave connecting grooves (3) on their opposite surfaces. The two connecting grooves (3) are joined together to form a hollow cylinder. The connecting screw (1) is screwed into the cylinder. The expansion connector (2) is provided with an upper expansion area (4) and a lower expansion area (5) at its upper and lower ends, respectively. The inner wall of the cylinder of the lower expansion area (5) is provided with an internal thread hole (52), and the connecting screw (1) is screwed into the internal thread hole (52). The upper expansion region (4) and the lower expansion region (5) are respectively provided with an upper threaded post (41) and a lower threaded post (51), and the threads of the lower threaded post (51) are opposite to those of the lower threaded post (51).

2. The invisible bidirectional expansion connector for sheet metal according to claim 1, characterized in that: The first connector (21) has a recessed groove (211) on its outer side wall, and the second connector (22) has a protruding elastic buckle (221) on its outer side wall. The elastic buckle (221) is fastened in the groove (211) to fix the first connector (21) and the second connector (22) into one piece.

3. The invisible bidirectional expansion connector for sheet metal according to claim 1, characterized in that: The upper expansion zone (4) is provided with an upper longitudinal groove (42) running through it along the axial direction.

4. The invisible bidirectional expansion connector for sheet metal according to claim 1, characterized in that: The lower expansion zone (5) is provided with a lower longitudinal groove (53) running through it along the axial direction.

5. The invisible bidirectional expansion connector for sheet metal according to claim 1, characterized in that: A deformation groove (6) is provided above the lower expansion zone (5), the deformation groove (6) penetrates the lower expansion zone (5) and is connected to the cylinder; the outer cross section of the deformation groove (6) is a concave inclined surface.

6. The invisible bidirectional expansion connector for sheet metal according to claim 1, characterized in that: The outer side of the upper expansion area (4) is provided with several positioning buckles (7) protruding along the circumference.

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