JP4726568B2 - Pre-coated steel door frame fixing structure - Google Patents

Description

  The present invention relates to a structure in which a door frame material produced by forming a pre-coated steel sheet is fixed to a housing with a simple method and good appearance.

Aluminum has traditionally been used for the metal door frame material that serves as the receiving side when the door is closed, but since aluminum material is inferior in fire resistance compared to steel material, it is a steel door as a member of class A fireproof structure. A frame material is needed.
The steel door frame material is assembled by processing a base plate such as a plated steel plate into a member having a target shape and welding the members together. For example, a hermetically sealed side wall of a building is formed by airtightly joining flanges of adjacent plate bodies with bolts and nuts (Patent Document 1).
WO2003 / 089727

Design and corrosion resistance are imparted to the door frame material by painting (post-coating) after assembly, but post-coating does not supply paint to the bottleneck of the door frame material, making it difficult to obtain sufficient corrosion resistance. For this reason, when used in an area exposed to a corrosive environment such as salt damage, red rust that impairs the appearance of the door frame tends to occur early.
If a pre-coated steel plate having better corrosion resistance than post-coating can be used for door frame materials, it is expected that a beautiful appearance can be maintained over a long period of time. However, when a pre-coated steel plate is used as a door frame material, a problem occurs in the door frame assembly process. Specifically, welding that impairs designability cannot be applied to the connection between precoated steel sheets, and screwing is employed.

The connection of the pre-coated steel plate by screwing requires a joint and increases the number of assembly steps. The increase in man-hours causes a decrease in productivity when manufacturing a unit-type door frame. If the joint is located on the surface of the door frame, the appearance will be deteriorated. Therefore, it is necessary to devise a joint design in which the joint is not conspicuous.
Further, when a cut plate cut from a pre-coated steel plate is connected, a cut end surface without a plating layer or coating film is likely to be exposed, and rust generation from the end surface is a concern. For these reasons, the use of precoated steel sheets for door frame materials has not been put to practical use.

When a joint design that eliminates the need for joints and exposes the end face becomes possible, the excellent properties inherent to the pre-coated steel sheet are utilized, and a door frame material that maintains a beautiful appearance over a long period of time can be obtained. In addition, since painting after assembly is basically unnecessary, the construction cost can be reduced.
The present invention has been devised to meet such demands, and is suitable for easy assembly of a good-looking door frame by using a pre-coated steel sheet formed into a shape having a screw pocket as a door frame material. It is an object to provide a fixed structure.

The present invention is a structure in which a door frame material having a predetermined cross-sectional shape having a gap serving as a screw pocket is fixed to a building frame using a precoated steel sheet as a raw material, and the gap serving as a screw pocket is formed by bending the precoated steel sheet. The door frame material is formed with fixing screws that are formed and the cross-sectional shape of the door frame material is constant with respect to the longitudinal direction, and is screwed into the gap that becomes the screw pocket through the screw hole on the building housing side. It is fixed to a housing.
It is also possible to screw the opening prevention screw into the door frame member along the direction intersecting the fixing screw from the outside of the gap into which the fixing screw is screwed.

Effects and embodiments of the invention

  Aluminum extruded materials used for door frames, window frames, etc. are molded into a cross-sectional shape with screw pockets in the extrusion process, and the screws are screwed into the screw pockets when assembling the door frames, window frames, etc. The extrudate is fixed. The present inventors investigated and examined various methods for imparting the same function as the screw pocket of the extruded material to the precoated steel sheet. As a result, when pre-coated steel sheets are processed into a predetermined cross-sectional shape by roll homing, bender bending, etc., they can be used as door frame materials assembled in the same way as aluminum extruded materials, and have significantly higher strength and fire resistance than aluminum extruded materials. It has been found that an excellent door frame can be obtained.

  Roll homing. A pre-coated steel sheet is formed into a cross-sectional shape having screw pockets by bending a bending machine or the like. Various cross-sectional shapes having screw pockets are exemplified (FIG. 1). The roll homing is advantageous because it can be formed into the same cross-sectional shape in the longitudinal direction of the pre-coated steel sheet 1 and a gap 2 serving as a screw pocket is secured on the end face even if the pre-coated steel sheet 1 is cut at any part. . It is preferable to fold the end face of the cut plate that has been cut to a predetermined width inward during the bending process for forming the gap 2 to be a screw pocket, so as to avoid external exposure of the cut end face that tends to cause corrosion.

A recent pre-coated steel sheet has a good coating film on the base steel, and coating film peeling does not occur in the processing shown in FIG. Advances in technology relating to the production of precoated steel sheets are also a factor that enables processing into cross-sectional shapes having gaps 2 that serve as screw pockets. In addition, when a high corrosion resistance material such as stainless steel or Zn—Al—Mg alloy plated steel sheet is used for the coating original plate, corrosion from the cut end face and occurrence of red rust are also suppressed.
The precoated steel sheet 1 formed into a cross-sectional shape having a gap 2 to be a screw pocket is cut into a predetermined size, and then fixed to a beam, a column, a strip, or the like of a building frame as a door frame material.
A case where the door frame material serving as the central pillar is screwed to the steel beam will be specifically described with reference to FIG. FIG. 2 shows a state where the upper part of the door frame member is fixed to the steel plate beam on the ceiling side, but it goes without saying that the lower part of the door frame member is fixed to the beam on the floor side in a similar work procedure. .

  The door frame material 10 is manufactured by roll homing of a precoated steel plate, has a substantially rectangular cross section, and gaps 11 and 12 serving as screw pockets are provided in front of the rectangular cross section by folding back the widthwise end of the precoated steel plate. It has been. On the side surface of the rectangular cross section, a sandwiching portion is formed in which the cushioning materials 13 and 14 that relieve the impact at the time of opening and closing the door are sandwiched, but utilizing that the sandwiching portion is formed by bending a precoated steel plate, The gaps 15 and 16 that become screw pockets are molded at the same time as the clamping part.

The door frame member 10 provided with the gaps 11, 12, 15, 16 has a constant cross-sectional shape in the longitudinal direction. For this reason, gaps 11, 12, 15, and 16 that become screw pockets face the end face even when cut at any site in the longitudinal direction, such as a door frame member made of extruded profile. Therefore, if it cut | disconnects to the length according to the size of a construction site, it will become a door frame which can be assembled | attached.
Screw holes 21, 22, 25, 26 are drilled in the steel beam 20, which is the counterpart material, in a positional relationship corresponding to the gaps 11, 12, 15, 16 of the door frame member 10. The screw holes 21, 22, 25, 26 are usually formed in the steel beam 20 by field work using a drill or the like, but a case where a large amount of the door frame material 10 of the same size and shape is fixed. Then, the screw holes 21, 22, 25, and 26 can be provided in the steel plate beam 20 in advance.

  Align the gaps 11, 12, 15, 16 of the door frame member 10 with the screw holes 21, 22, 25, 26 of the steel plate beam 20, and connect the screws 21a, 22a, 25a, 26a to the screw holes 21, 22, 25, 26 is passed through and screwed into the gaps 11, 12, 15, 16. Unlike aluminum extrusions that are easy to loosen, they are made of steel with high rigidity and strength, so the gaps 11, 12, 15, 16 are almost never opened even when screws 21a, 22a, 25a, 26a are screwed in. Screws 21a, 22a, 25a and 26a are tightened with elastic restoring force. In addition, when the opening prevention screws 21b, 22b, 25b, 26b are driven from the outside into the places where the screws 21a, 22a, 25a, 26a are screwed into the gaps 11, 12, 15, 16, the gaps 11, 12, 15, The opening of 16 is reliably prevented.

  In this way, the door frame member 10 produced by roll-homing or bending the pre-coated steel plate into a predetermined cross-sectional shape treats the gaps 11, 12, 15, and 16 in the same manner as the screw pockets of the extruded profile, It can be fixed to the building without the need for etc. Therefore, the adhering work is simple and can be finished with good appearance, and the advantages of the pre-coated steel sheet can be fully utilized. In other words, the exposed parts of the base steel are only the upper and lower end surfaces of the door frame material, and there is a healthy coating on the surface visible to the door user. And durability are maintained.

It can be understood from the following strength test that the door frame material is fixed to the building frame with sufficient bonding strength even when the gap formed by bending is used as a screw pocket.
As a material to be joined, a test piece was prepared by bending a pre-coated steel plate having a plate thickness of 1.6 mm and forming a gap having a maximum gap of 3.5 mm in the bent portion. As a counterpart material, a steel plate having a thickness of 1.6 mm in which a screw hole having a diameter of 4.5 mm was formed was used. After adjusting the gap of the test piece to the screw hole of the steel sheet, the test piece was joined to the steel sheet by screwing a screw having an effective diameter of 4 mm that penetrated the screw hole into the gap at a torque of 30 N · m.
Next, a force (tensile force) in the opposite direction was applied to each of the test piece and the steel plate, and the tensile force was increased until the test piece was separated from the steel plate. The tensile force at the time of separation was 120 to 590 N / mm ² , which was a sufficient bonding strength as a door frame supported by the building frame from the vertical direction.

  As described above, when a door frame material is produced by bending a precoated steel sheet into a predetermined shape, a gap that becomes a screw pocket is simultaneously formed. Even if the door frame material obtained is cut to a length suitable for the size of the construction site, the gap that becomes the screw pocket faces the end surface, so it is used for screwing when fixing the door frame material to the building frame Available. For this reason, the advantages of the precoated steel sheet with excellent corrosion resistance are utilized, and a door frame that does not require painting after construction and has a good appearance can be easily installed.

Cross section of pre-coated steel sheet with a gap to be a screw pocket Explanatory drawing of work to fix door frame material to building frame

Explanation of symbols

1: Pre-coated steel plate 2: Gaps that become screw pockets
10: Door frame material 11, 12, 15, 16: Clearance 13, 14: Buffer material
20: Steel plate beam 21, 22, 25, 26: Screw holes 21a, 22a, 25a, 26a: Fixing screws 21b, 22b, 25b, 26b: Opening prevention screws

Claims (2)

It is a structure in which a pre-coated steel plate is used as a raw material and a door frame material having a predetermined cross-sectional shape having a gap to be a screw pocket is fixed to a building frame.
The gap is formed by bending the precoated steel sheet so that the cut end surface of the precoated steel sheet is folded inward,
The cross-sectional shape of the door frame material is constant in the longitudinal direction,
A door frame material fixing structure, wherein a door frame material is fixed to a building frame with fixing screws that pass through a screw hole on the side of the building frame and are screwed into the gap. 2. The fixing structure according to claim 1, wherein an opening prevention screw is screwed into the door frame member along a direction intersecting with the fixing screw from the outside of the gap into which the fixing screw is screwed.

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