A metal door frame and metal door

Abstract

The utility model provides a kind of metal door frame and metal door, it is related to door and window technical field.The metal door frame, including door frame main body and two wall connecting plates;Door frame main body includes left stand, right stand and the upper crossbeam of connecting left stand and right stand top, left stand, right stand and the upper crossbeam constitute the rectangular frame for installing door leaf;Wall connecting plate includes left connecting plate and right connecting plate, left connecting plate and right connecting plate structure same and symmetrically set in the left and right sides of door frame main body;Left connecting plate and right connecting plate are recessed structure, the recessed structure has bottom wall and two side walls, bottom wall is fixedly connected with the outside of left stand or right stand, two side walls extend towards wall direction, for wrapping wall;At least one injection hole is equipped on the side wall of recessed structure, injection hole is used to inject filling material into recessed structure after left connecting plate and right connecting plate wrap wall.

Description

Technical Field

[0001] This utility model relates to the field of door and window technology, and in particular to a metal door frame and a metal door. Background Technology

[0002] In existing building door and window installation techniques, metal door frames are typically fixed directly to the wall and doorway using expansion bolts, nails, or cement mortar. The conventional approach involves placing the left and right uprights of the door frame close to the walls on either side, filling the gap between them with expanding foam, cement-based grout, or sealant to achieve basic connection and sealing. However, this installation method relies heavily on the adhesive strength of the filling material and lacks an effective mechanical restraint structure, resulting in limited connection strength between the door frame and the wall. Over long-term use, factors such as thermal expansion and contraction due to temperature changes, building settlement, vibrations from frequent door opening and closing, and aging of the filling material can easily lead to loosening, cracking, or even detachment between the door frame and the wall, severely affecting the door's normal function and durability. Utility Model Content

[0003] The main technical problem to be solved by this utility model is to overcome the technical defects of existing metal door frames and walls, which have low connection strength and are prone to loosening and falling off after long-term use. It provides a metal door frame and metal door that significantly improves the connection reliability, stability and durability by wrapping the wall with a wall connection plate and combining it with filling material to achieve double fixation.

[0004] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows:

[0005] In one aspect, a metal door frame is provided, including a door frame body and two wall connecting plates;

[0006] The main body of the door frame includes a left column, a right column, and an upper crossbeam connecting the top of the left column and the right column. The left column, the right column, and the upper crossbeam constitute a rectangular frame for installing the door leaf.

[0007] The wall connecting plate includes a left connecting plate and a right connecting plate, which have the same structure and are symmetrically arranged on the left and right sides of the door frame body;

[0008] The left connecting plate and the right connecting plate are in the form of a groove structure. The groove structure has a bottom wall and two side walls. The bottom wall is fixedly connected to the outer side of the left column or the right column. The two side walls extend toward the wall and are used to wrap the wall.

[0009] The sidewall of the groove structure is provided with at least one injection hole, which is used to inject filling material into the groove structure after the left connecting plate and the right connecting plate wrap the wall.

[0010] Furthermore, the injection hole is located in the top region of the left connecting plate and the right connecting plate.

[0011] Furthermore, there are multiple injection holes, which are spaced apart along the height direction of the left connecting plate and the right connecting plate.

[0012] Furthermore, the inner sidewalls of the left and right connecting plates are provided with reinforcing ribs or anti-slip textures.

[0013] Furthermore, the left connecting plate is composed of a left front connecting plate and a left rear connecting plate spliced ​​together;

[0014] The cross-sections of the left front connecting plate and the left rear connecting plate are both L-shaped and arranged in a mirror symmetrical manner.

[0015] The long side of the left front connecting plate is connected to the outer side of the left column, and its short side extends toward the wall.

[0016] The long side of the left rear connecting plate is connected to the outer side of the left column, and its short side extends toward the wall.

[0017] The long side of the left front connecting plate and the long side of the left rear connecting plate are close together, forming the groove structure together;

[0018] The injection hole is located on the short side of the left front connecting plate or the left rear connecting plate.

[0019] Furthermore, both the left front connecting plate and the left rear connecting plate have connecting holes on their long sides;

[0020] The outer side wall of the left column is provided with corresponding mounting holes;

[0021] The left front connecting plate and the left rear connecting plate are fixedly connected to the outer wall of the left column by fasteners passing through the connecting holes and engaging with the mounting holes.

[0022] Furthermore, the connecting hole is a flat, elliptical, elongated hole extending horizontally;

[0023] By adjusting the position of the fastener in the elongated hole, the relative distance between the left front connecting plate and the left rear connecting plate can be adjusted.

[0024] After adjustment, the short sides of the left front connecting plate and the left rear connecting plate extend towards the wall, and the long sides of the left front connecting plate and the left rear connecting plate together with the outer wall of the left column form the groove structure.

[0025] Secondly, a metal door is provided, including a metal door frame as described in the above technical solution.

[0026] The technical solution provided by this utility model has the following technical effects:

[0027] By setting grooved wall connecting plates on both sides of the main body of the door frame, the side walls of the left and right connecting plates can wrap around the wall from the front and back, forming a mechanical covering effect on the wall. This effectively enhances the physical interlocking force and tensile strength between the door frame and the wall. At the same time, injection holes are set on the side walls of the grooved structure, which can be used to inject foamed polyurethane, cement-based grout, or structural adhesive into the gap between the wall and the wall connecting plates after installation. After curing, a high-strength chemical anchoring layer is formed, realizing a dual fixing mechanism of "physical wrapping + chemical bonding". This greatly improves the overall strength and stability of the connection part, fundamentally solving the problems of loosening, cracking, and falling off caused by traditional metal door frames that rely solely on filling materials for bonding. Attached Figure Description

[0028] The above and other features and advantages of this invention will become more apparent from a detailed description of exemplary embodiments with reference to the accompanying drawings.

[0029] Figure 1 This is a partial structural diagram of a metal door frame provided in an embodiment of this utility model;

[0030] Figure 2 This is a schematic diagram of the first structure of the left connecting plate in a metal door frame provided in this embodiment of the utility model;

[0031] Figure 3 This is a schematic diagram of a second structure of the left connecting plate in a metal door frame provided in an embodiment of this utility model;

[0032] Figure 4 This is a schematic diagram of the third structure of the left connecting plate in a metal door frame provided in this embodiment of the utility model.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1. Left column, 2. Right column, 3. Left connecting plate, 4. Right connecting plate, 5. Injection hole, 6. Fastener;

[0035] 31. Front left connecting plate; 32. Rear left connecting plate. Detailed Implementation

[0036] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted.

[0037] The terms “a,” “one,” “the,” and “the” are used to indicate the existence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended meaning of inclusion and that other elements / components / etc. may exist in addition to the listed elements / components / etc.

[0038] Figure 1 This is a partial structural diagram of a metal door frame provided in an embodiment of this utility model (the upper crossbeam structure is omitted); Figure 2 This is a schematic diagram of the first structure of the left connecting plate in a metal door frame provided in this embodiment of the utility model; Figure 3 This is a schematic diagram of a second structure of the left connecting plate in a metal door frame provided in an embodiment of this utility model; Figure 4 This is a schematic diagram of the third structure of the left connecting plate in a metal door frame provided in this embodiment of the utility model. The above schematic diagram is only to illustrate the structural relationship related to the utility model and is not intended to represent the actual scale of the product.

[0039] Example 1

[0040] like Figures 1 to 4 As shown, this utility model provides a metal door frame that is structurally stable, firmly installed, and not easily loosened over long-term use. It is particularly suitable for residential buildings, public buildings, and industrial plants where high-strength door frame connection performance is required. This metal door frame, through an innovatively designed wall connection plate structure, achieves a dual fixing mechanism between the door frame body and the wall—a combination of physical wrapping and chemical anchoring. This significantly improves the overall connection strength and durability, effectively solving the problems of loosening, deformation, and even detachment of traditional metal door frames due to thermal expansion and contraction, vibration, or material aging during long-term use.

[0041] The metal door frame includes a main frame body and two wall connecting plates symmetrically arranged on the left and right sides of the main frame body. The main frame body consists of a left column 1, a right column 2, and an upper beam connecting the tops of the left column 1 and the right column 2, which together form a rectangular frame structure for installing the door leaf. The left column 1 and right column 2, as vertical load-bearing components, have high bending strength and torsional stiffness; the upper beam connects the tops of the two columns, ensuring the overall spatial geometric stability of the door frame. The main frame body is made entirely of metal, preferably steel or aluminum alloy, possessing good mechanical properties and corrosion resistance. Surface treatments such as electrostatic spraying, powder coating, or anodizing can be applied according to actual engineering requirements to enhance its aesthetic appearance and environmental adaptability.

[0042] The wall connection plates include a left connection plate 3 and a right connection plate 4, both with identical structures and arranged in a mirror-symmetrical manner on the left and right sides of the door frame body. The left connection plate 3 is located on the outside of the left column 1, and the right connection plate 4 is located on the outside of the right column 2, used to securely connect to the left and right walls of the building, respectively. Each wall connection plate has a groove-like structure, consisting of a bottom wall and two side walls. The bottom wall is fixedly connected to the outer side of the left column 1 or right column 2 of the door frame body. The two side walls extend horizontally from the edge of the bottom wall towards the wall, forming a U-shaped cross-section structure facing the wall opening. When the door frame is installed, these two side walls can partially enclose the wall within their internal space from the outside, thus achieving a mechanical covering effect on the wall. This enveloping design clamps the wall between the side walls, forming a "click-lock"-like physical interlocking relationship, greatly enhancing the tensile and shear resistance between the door frame and the wall.

[0043] At least one injection hole 5 is provided on the sidewalls of the left connecting plate 3 and the right connecting plate 4. This injection hole 5 is used to inject filling material into the gaps between the grooved structure and the wall after the wall connecting plate has finished wrapping the wall. The filling material can be self-foaming polyurethane, cement-based grout, epoxy resin structural adhesive, polyurethane sealant, or other polymeric or inorganic materials with expansion, adhesion, and curing strength. After injection, these filling materials fill all gaps between the wall and the sidewalls, and after curing, form a robust integral structure, firmly bonding the wall connecting plate to the wall. Because the filling material not only fills the gaps but also tightly bonds the metal to the wall material (such as concrete, brick masonry, or aerated concrete blocks) through chemical bonding, a second fixing mechanism—chemical anchoring—is formed. Combined with the aforementioned physical wrapping effect, this invention achieves a double-insurance connection mode of "mechanical wrapping + chemical bonding," greatly improving the reliability and service life of the connection between the door frame and the wall.

[0044] Furthermore, in another embodiment, the injection hole 5 is located in the top area of ​​the left connecting plate 3 and the right connecting plate 4. This design is particularly suitable for using highly fluid filling materials, such as cement-based grout. Because cement-based grout has good self-leveling properties and high fluidity, when injected from the top, the material can flow naturally downwards under gravity, gradually filling the vertical gap between the entire sidewall and the wall, ensuring a dense and void-free filling. The location of the top injection port facilitates construction operations; workers can directly perform the grouting operation through the injection hole 5 after the door frame is installed.

[0045] However, when using filler materials with poor flowability, such as polyurethane foam, single top injection cannot guarantee uniform and complete filling, easily leading to problems such as incomplete filling or air bubble aggregation. Therefore, in some embodiments, multiple injection holes 5 are provided, spaced apart along the height direction of the left connecting plate 3 and the right connecting plate 4. For example, one or more injection holes 5 can be provided at the upper, middle, and lower parts of the connecting plates, forming a multi-point injection port layout. During construction, polyurethane foam can be injected sequentially from bottom to top, allowing the foam material to rise gradually and fully expand, filling the space between the entire sidewall and the wall. The multi-point injection design effectively avoids filling blind spots caused by insufficient material flowability, ensuring the integrity and sealing of the connection area. Furthermore, the multiple injection holes 5 can also be used as vents to release trapped air during injection, preventing air resistance from affecting the filling quality.

[0046] To further enhance the bonding strength between the wall connection plates and the wall, reinforcing ribs or anti-slip textures are added to the inner sidewalls of the left connection plate 3 and the right connection plate 4. The reinforcing ribs can be longitudinally or transversely arranged raised strips, or they can be mesh-like or wavy reinforcing ribs. Their function is to increase the structural stiffness of the sidewalls and prevent buckling deformation under stress. The anti-slip texture is created by pressing fine embossed patterns, such as sawtooth, diamond, or dot matrix patterns, onto the inner surface of the sidewalls. This increases the friction and mechanical interlocking force between the metal surface and the filler material, improving the shear resistance of the bonding interface. These surface treatment measures significantly improve the adhesion between the filler material and the metal sidewalls, reducing the risk of interface delamination.

[0047] In a preferred embodiment, the left connecting plate 3 is not integrally formed, but is constructed by splicing a left front connecting plate 31 and a left rear connecting plate 32. Both the left front connecting plate 31 and the left rear connecting plate 32 have L-shaped cross-sections and are arranged in a mirror-symmetrical manner. The long side of the left front connecting plate 31 is attached to the outer surface of the left column 1 and fixed by fasteners 6; its short side extends horizontally towards the front wall. The long side of the left rear connecting plate 32 is also attached to the outer surface of the left column 1 and arranged parallel to the long side of the left front connecting plate 31, while its short side extends towards the rear wall. After the left front connecting plate 31 and the left rear connecting plate 32 are installed, their short sides clamp the wall, while their long sides together adhere to the outside of the left column 1, forming a complete groove-like structure that clamps and wraps the wall from both sides.

[0048] The right connecting plate 4 adopts the same structural form as the left connecting plate 3 and is installed on the outside of the right column 2 to achieve symmetrical wrapping of the right side wall.

[0049] This modular structure offers excellent adaptability and adjustability. Specifically, both the left front connecting plate 31 and the left rear connecting plate 32 have connecting holes along their long sides, while corresponding mounting holes are provided on the outer side wall of the left column 1. By passing bolts, self-tapping screws, or other types of fasteners 6 through the connecting holes and screwing them into the mounting holes, the left front connecting plate 31 and the left rear connecting plate 32 can be securely fixed to the left column 1. Notably, the connecting holes are designed as elongated, flat oval holes extending horizontally. This structure allows the fasteners 6 to slide horizontally within the range of the elongated holes, thereby enabling adjustment of the relative distance between the left front connecting plate 31 and the left rear connecting plate 32. During actual installation, the distance between the two connecting plates can be fine-tuned according to the actual thickness of the wall to precisely match the wall width, ensuring that the sidewalls fit tightly against the wall surface without leaving excessive gaps. After adjustment, tighten the fasteners 6 to lock the position, forming a stable and reliable connection structure.

[0050] This adjustment mechanism not only improves the versatility of the door frame, making it suitable for walls of different thicknesses, but also addresses installation challenges caused by uneven walls or construction errors on-site, thereby increasing the tolerance for construction errors and assembly efficiency.

[0051] In addition to the above structure, various extended designs are possible for the wall connection plate. For example, elastic sealing strips, such as EPDM rubber strips, silicone strips, or polyurethane sealing strips, can be installed at the free ends of the side walls to provide an initial sealing effect when wrapping the wall, preventing dust, rainwater, or air penetration and improving the airtightness and watertightness of the door frame. Another example is the pre-embedding of metal mesh or fiber-reinforced mesh inside the grooved structure to enhance the crack resistance and overall strength of the filling material, especially suitable for large door frames or applications bearing heavy loads. Furthermore, a one-way valve or sealing cap can be installed at injection hole 5 to prevent the filling material from overflowing or becoming contaminated before curing, and also to prevent foreign objects from entering the hole and affecting subsequent use.

[0052] During the construction and installation process, the main body of the door frame is first placed in the door opening position, and its verticality, horizontality and diagonal dimensions are adjusted to ensure that the installation accuracy of the door frame meets the specifications.

[0053] Install the left front connecting plate 31 and the left rear connecting plate 32 of the left connecting plate 3 on the outside of the left column 1, and adjust the distance between them according to the actual thickness of the left wall so that the short side can clamp the wall from the front and rear sides. Similarly, install the right connecting plate 4 on the outside of the right column 2 to complete the wrapping of the right wall.

[0054] Install the upper crossbeam, positioning it atop the left column 1 and right column 2, and connect them using welding, fasteners 6, and clips. The installation sequence can be adjusted according to the actual product design.

[0055] Check that the left connecting plate 3 and the right connecting plate 4 are perpendicular and without obvious misalignment. After confirming that everything is correct, begin injecting the filling material into the groove structure through the injection hole 5. If cement-based grout is used, inject it all at once from the top injection hole 5 until the material overflows from below, ensuring full filling. If polyurethane foam is used, inject it sequentially from bottom to top through multiple injection holes 5, controlling the foaming speed and expansion amount to avoid excessive expansion that could cause sidewall deformation. After filling, allow the material to cure completely, forming a robust, integrated connection structure. Here, different wall connection plates with different structures should be selected depending on the filling material used.

[0056] This invention provides a metal door frame with significant advantages over traditional installation methods. Traditional methods typically involve simply attaching the door frame posts close to the wall, filling the gap with a small amount of cement mortar or expanding foam. This simple connection relies primarily on the adhesive strength of the filling material, lacking mechanical restraint. Consequently, over long-term use, cracks and detachment can easily occur due to temperature changes, humidity fluctuations, or structural vibrations, ultimately leading to a loose door frame. In contrast, this invention provides additional mechanical locking force through the wall-mounted connecting plate's encasing structure. Even if the filling material partially fails, the door frame can still maintain a certain connection strength through physical encasing, significantly extending its service life.

[0057] Furthermore, this metal door frame can be integrated with other building components. For example, a top connecting plate can be added to the top of the upper beam to form a three-sided wrapping structure, further improving the overall connection performance; an adjustable anchor bolt or shim system can also be installed at the bottom of the door frame for fine-tuning the height and flatness of the door frame; the door frame can also be combined with fireproof and soundproof materials to create a composite door frame system that combines high-strength connection performance with special functions, meeting the needs of high-rise buildings, hospitals, schools, and other scenarios with high requirements for safety and comfort.

[0058] In summary, the metal door frame disclosed in this utility model achieves a high-strength and high-durability connection between the door frame and the wall through an innovative wall connection plate design, solving the problems of weak connection and easy loosening in traditional installation methods. It has the advantages of reasonable structure, convenient construction, wide applicability, and safety and reliability, and has good prospects for promotion and application.

[0059] Example 2

[0060] This utility model provides a metal door, which includes not only the metal door frame as described in Embodiment 1, but also a door leaf, door leaf connectors, sealing components, and matching hardware accessories, forming a complete door system. It is suitable for indoor or outdoor doorway installation in various building types such as residential buildings, commercial spaces, industrial plants, hospitals, and schools, and is especially suitable for frequently used areas or high-wind-pressure environments where high door frame connection strength is required.

[0061] One of the core components of a metal door is the metal door frame, the structure of which adopts the technical solution described in Example 1.

[0062] The metal door also includes a door leaf, which is rotatably mounted between the left post 1 and right post 2 of the metal door frame via door leaf connectors. The door leaf is typically constructed of a metal panel (such as galvanized steel, stainless steel, or aluminum alloy) and internal filling material (such as rock wool, glass wool, polyurethane foam, or honeycomb paper core), providing good heat insulation, sound insulation, fire resistance, and moisture resistance. The door leaf's dimensions match the rectangular frame of the main door body, and it has sealing grooves around its perimeter for installing sealing components.

[0063] Door panel connectors include hinges, pivot pins, or eccentric adjustment hinges, typically made of stainless steel or high-strength carbon steel, offering excellent load-bearing capacity and corrosion resistance. One side of the hinge is fixed to the side of the door panel, and the other side is fixed to the left post 1 or right post 2 of the door frame, enabling the door to open and close. Some high-end models can be equipped with hinges featuring three-dimensional adjustment, allowing for fine-tuning of the door panel's vertical, horizontal, and front-back positions after installation to ensure uniform gaps between the door panel and the door frame, and a tight seal when closed.

[0064] The sealing assembly includes a sealing strip around the door frame, typically made of rubber, silicone, or thermoplastic elastomer (TPE), installed on the inner edge of the door frame or at the corresponding position on the door leaf. When the door is closed, the sealing strip deforms under pressure, filling the gap between the door leaf and the door frame, effectively blocking the transmission of air, moisture, noise, and smoke, thus improving the overall sealing performance of the door. The sealing strip can be designed in various cross-sectional shapes, such as D-shape, E-shape, P-shape, or hollow circular, to meet different sealing requirements.

[0065] In addition, metal doors can be equipped with a variety of hardware accessories, such as door locks, handles, door closers, door catches, peepholes, and security chains, to meet the needs of safety, convenience, and aesthetics. Door locks can be mechanical, electronic, or smart locks, supporting multiple opening methods such as keys, passwords, fingerprints, card swipes, or remote control. Door closers are used to automatically close the door, preventing energy waste or security risks caused by prolonged door opening. Door catches are used to hold the door in place when it is open, preventing it from being blown by the wind and hitting the wall.

[0066] The metal door provided by this utility model significantly improves the connection strength and durability between the door frame and the wall by adopting a metal door frame with a double fixing mechanism, solving the technical problem of traditional door frames being prone to loosening and falling off. At the same time, the reasonable configuration of the door leaf, sealing components and hardware accessories further enhances the functionality, safety and comfort of the door. It has the advantages of reasonable structure, convenient construction, strong adaptability and long service life, and has broad market application prospects.

Claims

1. A metal door frame, characterized in that, Includes the main door frame and two wall connecting panels; The main body of the door frame includes a left column (1), a right column (2) and an upper crossbeam connecting the top of the left column (1) and the right column (2). The left column (1), the right column (2) and the upper crossbeam constitute a rectangular frame for installing the door leaf. The wall connecting plate includes a left connecting plate (3) and a right connecting plate (4). The left connecting plate (3) and the right connecting plate (4) have the same structure and are symmetrically arranged on the left and right sides of the door frame body. The left connecting plate (3) and the right connecting plate (4) are in the form of a groove structure. The groove structure has a bottom wall and two side walls. The bottom wall is fixedly connected to the outer side of the left column (1) or the right column (2). The two side walls extend toward the wall and are used to wrap the wall. At least one injection hole (5) is provided on the side wall of the groove structure. The injection hole (5) is used to inject filling material into the groove structure after the left connecting plate (3) and the right connecting plate (4) wrap the wall.

2. A metal door frame according to claim 1, characterized in that, The injection hole (5) is located in the top area of ​​the left connecting plate (3) and the right connecting plate (4).

3. A metal door frame according to claim 1, characterized in that, There are multiple injection holes (5), which are distributed at intervals along the height direction of the left connecting plate (3) and the right connecting plate (4).

4. A metal door frame according to any one of claims 1 to 3, characterized in that, The inner sidewalls of the left connecting plate (3) and the right connecting plate (4) are provided with reinforcing ribs or anti-slip textures.

5. A metal door frame according to claim 1, characterized in that, The left connecting plate (3) is composed of a left front connecting plate (31) and a left rear connecting plate (32). The cross-sections of the left front connecting plate (31) and the left rear connecting plate (32) are both L-shaped and arranged in a mirror symmetrical manner; The long side of the left front connecting plate (31) is connected to the outer side of the left column (1), and its short side extends toward the wall. The long side of the left rear connecting plate (32) is connected to the outer side of the left column (1), and its short side extends toward the wall. The long side of the left front connecting plate (31) and the long side of the left rear connecting plate (32) are close to each other, together forming the groove structure; The injection hole (5) is located on the short side of the left front connecting plate (31) or the left rear connecting plate (32).

6. A metal door frame according to claim 5, characterized in that, Both the left front connecting plate (31) and the left rear connecting plate (32) have connecting holes on their long sides; The left column (1) has mounting holes on its outer side wall. By passing fasteners (6) through the connecting holes and engaging with the mounting holes, the left front connecting plate (31) and the left rear connecting plate (32) are fixedly connected to the outer wall of the left column (1).

7. A metal door frame according to claim 6, characterized in that, The connecting hole is a flat, elliptical, elongated hole extending horizontally. By adjusting the position of the fastener (6) in the elongated hole, the relative distance between the left front connecting plate (31) and the left rear connecting plate (32) can be adjusted; After adjustment, the short sides of the left front connecting plate (31) and the left rear connecting plate (32) extend toward the wall, and the long sides of the left front connecting plate (31) and the left rear connecting plate (32) together with the outer wall of the left column (1) form the groove structure.

8. A metal door, characterized in that, Including the metal door frame as described in any one of claims 1 to 7.

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