GB2553595B

GB2553595B - Door with improved strength using laminated veneer lumber

Info

Publication number: GB2553595B
Application number: GB1617363.5A
Authority: GB
Inventors: Myung Taek No
Original assignee: Trinity Glass International
Current assignee: Trinity Glass International
Priority date: 2016-09-12
Filing date: 2016-10-13
Publication date: 2019-09-18
Anticipated expiration: 2036-10-13
Also published as: KR101898778B1; KR20180029307A; GB2553595A; GB201617363D0

Description

DOOR WITH IMPROVED STRENGTH USING LAMINATED VENEER LUMBER BACKGROUND OF THE INVENTION

Field of the Invention [01] The present invention relates to a door, and more particularly, to a door which has a strengthened structure using a laminated veneer lumber (LVL) in order to prevent invasion from the outside and includes a urethane insulating layer therein.

Background Art [02] In general, a glass fiber reinforced plastic (GRP) door which has been used generally includes: a pair of door skins molded with sheet molding compound (SMC); and urethane foam formed between the door skins. Here, the SMC used for molding the door skins contains various ingredients including glass fiber in order to reinforce strength.

[03]Korean Patent Publication No. 10-2012-58052 discloses a GRP door (hereinafter, called a 'door'). In Korean Patent Publication No. 10-2012-58052, the door generally has a specific pattern formed on the front face thereof in order to cause an esthetic sense to viewers. In order to form a pattern on the surface of the door, especially, on an outer skin exposed to the outside of a house, concave lines are formed on the outer skin so as to form an outline of a desired pattern, for instance, several rectangles or squares, by the lines.

[04] However, as described above, the door which has the inner skin and the outer skin in the state where the urethane layer is interposed between the inner skin and the outer skin has a disadvantage in that strength of the door is deteriorated because the concave lines are formed on the outer surface of the door. Moreover, such a door which is used to limit or allow entry to and egress from the house cannot guarantee safety in aspects of crime prevention and security because of deterioration in strength of the door.

SUMMARY OF THE INVENTION

[05] Accordingly, the present invention has been made in view of the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide a door which sufficiently guarantee a structural strength and insulation effect.

[06] It is another object of the present invention to provide a door having excellent machinability, such as adding attachments at a middle part of the door.

[07] It is a further object of the present invention to provide a door which makes a flow of a urethane foaming liquid smooth when the urethane foaming liquid is injected to form an insulating layer in the door.

[08] In fact, reinforcement of structural strength means to sufficiently prevent a damage of the door by invasion from the outside, and ultimately means to provide a door favorable in aspects of crime prevention and security. Furthermore, excellent machinability of a part of the door means to easily machine the structure to add additional attachments, such as a mail box, on the door, and also means to secure sufficient stability even though the door is partially machined. Additionally, the smooth flow of the urethane foaming liquid means that the internal structure is not changed or the skins are not deformed by the flow of the foaming liquid and that the insulating layer can be formed easily.

[09]To accomplish the above object, according to the present invention, there is provided a door comprising: an outer skin and an inner skin which have concave parts and plane parts, the concave parts being concavely formed to form a pattern and the plane parts respectively formed between the concave parts, the plane parts of the respective outer skin and inner skin all lying in the same plane, the outer skin and the inner skin being spaced apart from each other; frames which form edge portions between the outer skin and the inner skin; an insulating layer formed inside the frames by foaming liquid injected between the outer skin and the inner skin and foamed; a plurality of reinforcing plates made of laminated veneer lumber (LVL) which are mounted between the outer skin and the inner skin to be respectively spaced apart from both of the outer skin and the inner skin, the reinforcing plates also being spaced apart from one another; and supporting means for supporting the reinforcing plates at the positions spaced apart from the outer skin and the inner skin within the insulating layer, wherein the outer skin and the inner skin at the concave parts are relatively thicker than the outer skin and the inner skin at the plane parts.

[10] Preferably, the reinforcing plates are mounted at the plane parts between the concave parts formed on at least one of the outer skin and the inner skin and are divided by the concave parts. [11] Desirably, the supporting means are pins of which both end portions are respectively supported inside the outer skin and the inner skin while penetrating through the reinforcing plates. [12] Preferably also, vertical reinforcing frames are mounted at the central portion where a door knob is mounted, are in contact with the inner surfaces of a vertical frame of the door, have a length in the vertical direction, and are respectively spaced apart from the reinforcing plates.

[13] Desirably also, each of the reinforcing plates has a plurality of through-holes through which the foaming liquid flows . [14] The door according to the present invention has concave parts for forming various patterns on the skins which are the surfaces of the door. Moreover, even though the urethane insulating layer becomes thinner due to the concave parts, the LVL reinforcing plates mounted between the inner skin and the outer skin can reinforce strength of the door sufficiently. [15] Furthermore, the skin having concave parts on which the patterns are formed is relatively thicker than the skin having the plane parts. Therefore, it can prevent that strength is deteriorated at the parts of the skin where the concave parts are formed, and so, the door according to the present invention is actually enhanced in strength. Here, to enhance strength of the door means that it increases the time required to break the door when someone invades. [16] Additionally, a plurality of LVL reinforcing plates are fixed at the middle height. Such reinforcing plates reinforce strength of the whole door and enhance machinability at the parts where the reinforcing plates are mounted. For instance, in order to mount a mail box or a window onto the door, the corresponding part of the door must be machined. In this instance, because the parts where the LVL reinforcing plates are mounted are thick, the door can be easily machined and can prevent deterioration in strength by machining. [17] In addition, the LVL reinforcing plates are actually advantageous for insulation. Namely, because the LVL reinforcing plates have better insulation function than metallic reinforcing components which may be adopted for reinforcement, it is more advantageous in insulating the inside of a house. Moreover, in fact, because the LVL reinforcing plates have a predetermined area, they are advantageous for preventing noise.

[18] Furthermore, the reinforcing plates according to the present invention are supported in the middle between the inner skin and the outer skin. Therefore, the foaming liquid supplied between the inner skin and the outer skin can sufficiently fill the space between the inner skin and the outer skin while smoothly flowing between the inner skin and the outer skin. As described above, the insulating layer of the door according to the present invention can actually reduce a defect rate and contribute to enhancement of the insulating function. Additionally, the door according to the present invention can enhance flowability of the foaming liquid further because the reinforcing plates have a plurality of through-holes .

BRIEF DESCRIPTION OF THE DRAWINGS

[19] The above and other objects, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments of the invention in conjunction with the accompanying drawings, in which : [20] FIG. 1 is a front view showing an example of a structure of a door according to the present invention; [21] FIG. 2 is a cross sectional view of the door according to the present invention; [22] FIG. 3 is a sectional view taken along the line of A-A of FIG. 1; [23] FIG. 4 is a sectional view taken along the line of B-B of FIG. 1; [24] FIG. 5 is a sectional view taken along the line of C-C of FIG. 1 and [25] FIG. 6 is a sectional view taken along the line of D-D of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[26] Hereinafter, a door according to preferred embodiments of the present invention will be described in detail with reference to the attached drawings. First, referring to FIGS. 1 and 2, a door according to a preferred embodiment of the present invention includes: a pair of door skins 10 and 20 molded with sheet molding compound (SMC); frames 18 and 19 interposed between edge portions of the door skins 10 and 20; and a urethane insulating layer 16 formed between the door skins 10 and 20. The door skins 10 and 20 are an outer skin 10 exposed to the outside of a house and an inner skin 20 exposed to the inside of the house. Here, the SMC is a mixture in which synthetic resin, a strength reinforcing material, such as glass fiber for reinforcing strength, and other added materials are mixed. [27] The urethane insulating layer 16 is formed between the skins 10 and 20 when urethane foam liquid is injected. The skins 10 and 20 respectively have concave parts 14 which are concavely molded to be symmetrical inside and outside. Such concave parts 14 are to form specific patterns or shapes on the front side and the rear side of the door. As shown in FIG. 1, for instance, the door may have a plurality of rectangular shapes 13 on the front side and the rear side thereof. [28] P1 ane parts 17 having the same planes are formed on the inner side and the outer side based on the concave parts 14 formed in the rectangular shapes 14. A plurality of the plane parts 17 are formed on the inside and the outside of the concave parts 14. For instance, the plane parts 17 have an inner plane part 17a formed on the inside of the concave part 14 and an outer plane part 17b formed on the outside of the concave part 14. Here, the concave parts 14 are parts that are generally thinner than the plane parts 17.

[29] In the present invention, reinforcing plates 22 made of wood are respectively mounted in the middle parts of the outer skin 10 and the inner skin 20 which correspond to the plane parts 17. Such wood reinforcing plates 22 are in a plate type having a predetermined thickness, and made with laminated veneer lumber (LVL). [30] In the embodiment illustrated in FIG. 1, the reinforcing plates 22 are respectively arranged between the concave parts 14, and for instance, include: a first reinforcing plate 22a mounted at the central part of the door in the width direction; a pair of second reinforcing plates 22b arranged up and down from the center of the first reinforcing plate 22a; and four third reinforcing plates 22c mounted inside the concave parts 14.

[31] Such reinforcing plates 22 are mounted to form planes which are parallel to one another between the inner skin 20 and the outer skin 10. As shown in FIGS. 2 to 4, the reinforcing plates 22 are arranged in the middle between the outer skin 10 and the inner skin 20. That is, the reinforcing plates 22 are respectively spaced apart from the outer skin 10 and the inner skin 20 at predetermined spacings, and the urethane insulating layer 16 is formed in the intervening space. [32] As described above, when the reinforcing plates 22 are spaced apart from the outer skin 10 and the inner skin 20, because the foaming liquid flows smoothly when the foaming liquid is injected, there is no problem between the skins 10 and 20 and the urethane insulating layer 16. If the foaming liquid does not flow smoothly, the insulating layer 16 may not be formed uniformly.

[33] The reinforcing plates 22 are configured to be inserted between the plane parts 17 of the outer skin 10 and the inner skin 20 except the concave parts 14, and such a configuration is designed to make the flow of the foaming liquid smooth. In other words, a plurality of the reinforcing plates 22 are separated by the concave parts 14. In the preferred embodiment, the reinforcing plates 22 are mounted between the plane parts 17 of the skins 10 and 20, but the present invention is not limited to the above, but many reinforcing plates 22 may be formed within a range not to interrupt the smooth flow of the foaming liquid. [34] The reinforcing plates 22 are made of wood, and preferably, made with LVL. It is preferable that a plurality of the reinforcing plates 22 be mounted between the outer skin 10 and the inner skin 20 not to interrupt the flow of the foaming liquid. Here, as shown in the drawings, in an aspect of the flow of the foaming liquid, it is more preferable that the reinforcing plates 22 be mounted between the plane parts 17 and other than at the concave parts 14 between the outer skin 10 and the inner skin 20. [35] In a manufacturing process of the door according to the present invention, the foaming liquid is injected between the outer skin 10 and the inner skin 20 which are molded to have a predetermined shape by a mold. Moreover, because the foaming liquid injected between the outer skin 10 and the inner skin 20 has some pressure, a device for keeping the positions of the outer skin 10 and the inner skin 20 is disposed. Furthermore, in order to form the insulating layer 16 between the outer skin 10 and the inner skin 20 in the state where the reinforcing plates 22 are mounted between the outer skin 10 and the inner skin 20 to be spaced apart from the outer skin 10 and the inner skin 20, a support member for supporting the reinforcing plates 22 between the outer skin 10 and the inner skin 20 is needed.

[36] In order to support the reinforcing plates 22 which are respectively spaced apart from the outer skin 10 and the inner skin 20, as shown in FIG. 3, a plurality of nails or pins (P) are mounted at the reinforcing plates 22 to protrude bilaterally. Preferably, such pins (P) penetrate through the reinforcing plates 22 so that both end portions are supported by the outer skin 10 and the inner skin 20. [37] Such pins (P) can keep the reinforcing plates 22 at the designated positions even though the foaming liquid is injected between the outer skin 10 and the inner skin 20. Additionally, when foaming is finished and the door having the insulating layer 16 between the outer skin 10 and the inner skin 20 is completed, it is natural that the pins (P) are not exposed to the outside because they are hidden by the outer skin 10 and the inner skin 20. [38] In the present invention, the LVL reinforcing plates 22 are mounted in the state where they are respectively spaced apart from the outer skin 10 and the inner skin 20. [39] When the door is manufactured using the outer skin 10 and the inner skin 20, in order to form the urethane insulating layer 16 between the skins 10 and 20 in the state where the skins 10 and 20 are spaced apart from each other at a predetermined spacing, the rectangular frames 18 and 19 formed along the edge portions of the skins 10 and 20 must be mounted between the skins 10 and 20. In fact, the insulating layer 16 is formed in the state where the frames 18 and 19 are interposed between the skins 10 and 20. [40] As shown in FIG. 1, the door according to the present invention includes: a pair of vertical frames 19 mounted at both right and left end portions of the door in the vertical direction; and a pair of horizontal frames 18 and 18A mounted at the top and the bottom of the door in the horizontal direction. In the preferred embodiment, the horizontal frames 18 and 18A are mounted between the vertical frames 19, and so, the frames 18, 18A and 19 generally form a rectangular frame.

[41] As shown in FIGS. 1 to 4, the vertical frames 19 include: outer vertical frames 19a which are mounted at the outermost portion and are made of synthetic resin to prevent penetration of moisture; and inner vertical frames 19b which are made of wood, for instance, LVL, and are mounted to come into contact with the inner surface of the outer vertical frames 19a. [42] As shown in FIGS. 1, 5 and 6, the horizontal frame 18 which is mounted at the top of the door in the horizontal direction includes: an outer horizontal frame 18a which is mounted at the top of the door and is made of synthetic resin to prevent penetration of moisture; and an inner horizontal frame 18b which is made of wood, for instance, LVL, and is mounted to come into contact with the inner surface of the outer horizontal frame 18a. [43] As shown in FIG. 6, the horizontal frame 18A mounted at the bottom of the door in the horizontal direction includes: an outer horizontal frame 18a which is mounted at the bottom of the door and is made of synthetic resin to prevent penetration of moisture; and an inner horizontal frame 18c which is made of synthetic resin and is mounted to come into contact with the inner surface of the outer horizontal frame 18a. As described above, in order to securely prevent penetration of moisture at the bottom of the door and considering that cutting of the door to adjust the length of the door is achieved at the bottom of the door, the outer horizontal frame 18a and the inner horizontal frame 18c of the horizontal frame 18A mounted at the bottom of the door are all molded with a synthetic resin material.

[44] The reinforcing plates 22 which are used to reinforce strength of the door are mounted in the middle part of the door when they are seen from the front of the door as shown in FIG. 1, and in fact, they are mounted to be spaced apart from the horizontal frames 18 and 18A and the vertical frames 19 at predetermined spacings. The spacings between the reinforcing plates 22 and the horizontal frames 18 and 18A and the vertical frames 19 are to make the flow of the foaming liquid sufficiently smooth when the foaming liquid is injected to form the insulating layer 16. [45] When the door is viewed from the front as shown in FIG. 1, to mount the reinforcing plates 22 at the middle part of the door means that strength at the middle part of the door is sufficiently reinforced. Because the reinforcing plates 22 are made of wood, preferably, LVL, a window or a mail box can be easily mounted in the middle of the door and the reinforcing plates 22 made of LVL can maintain sufficient strength even though such a window or a mail box is mounted on the door. [46] The door gets narrower at the parts where the concave parts 14 are formed. That is, the parts where the concave parts 14 are formed are relatively thinner than the plane parts 17. Therefore, the strength of the door may be reduced at the concave parts 14. The area of the concave parts 14 is very small in comparison with the area of the plane parts 17, but it is true that the concave parts 14 are somewhat weak in an aspect of strength. [47] In order to secure strength of the door at the concave parts 14, the corresponding parts of the outer skin 10 and/or the inner skin 20 are molded to be thicker. The skins 10 and 20 are molded by the mold. When the skins 10 and 20 are molded, the concave parts 14 of the skins 10 and 20 are molded to be thicker than the plane parts 17 of the skins 10 and 20.

[48] For instance, if the thickness of the skin corresponding to the plane parts 17 is about 2mm, the thickness of the skin corresponding to the concave parts 14 is about 3mm. In other words, in order to reinforce strength of the concave parts 14, the skins 10 and 20 are formed in such a way that the parts of the skins 10 and 20 corresponding to the concave parts 14 is relatively thicker than the plane parts 17. As described above, when the skins 10 and 20 are formed to have a difference in thickness between the concave parts 14 and the plane parts 17, it enhances strength of the skins, and strength of the concave parts 14 can be sufficiently reinforced when the urethane insulating layer 16 is formed integrally between the skins. [49] As described above, the vertical frames 19 of the door include the outer vertical frames 19a made of synthetic resin and the inner vertical frames 19b molded with LVL. In order to reinforce strength of the vertical frames 19, vertical reinforcing frames 26 having a predetermined length are mounted at the center of the inside of the vertical frames 19 in the vertical direction. The vertical reinforcing frames 26 are mounted, for instance, at a part where a door knob is mounted in order to further reinforce strength. [50] Preferably, the vertical reinforcing frames 26 are mounted to be spaced apart from a first reinforcing plate 22a and a third reinforcing plate 22c at predetermined spacings so that the foaming liquid to form the insulating layer 16 can flow smoothly. When the foaming liquid is injected to form the insulating layer 16, the reinforcing plates 22 are spaced apart from the vertical frames 19 and the horizontal frames 18 to make the flow of the foaming liquid smooth, and the reinforcing plates 22 are also spaced apart from one another at predetermined spacings . [51] Moreover, in another preferred embodiment, a plurality of the reinforcing plates 22 are arranged at the plane parts 17 between the concave parts 14 in order to sufficiently secure fluidity of the foaming liquid. When the foaming liquid is injected to form the insulating layer 16, in order to further secure fluidity of the foaming liquid, the reinforcing plates 22 may have a plurality of through holes. In other words, the reinforcing plates 22 are mounted to be respectively spaced apart from the outer skin and the inner skin and includes a plurality of the through holes formed therein, so that the foaming liquid can flow penetrating the reinforcing plates 22 so as to further secure fluidity of the foaming liquid. [52] As described above, in the door having the concave parts 14 and the plane parts 17, the reinforcing plates 22 made with LVL for reinforcing strength of the door are mounted between the inner skin 20 and the outer skin 10, and the parts of the skins corresponding to the concave parts 14 are made to be thicker than the plane parts 17 in order to reinforce general strength of the door. [53] It will be understood by those of ordinary skill in the art that various changes and equivalences may be made in the embodiments of the present invention without departing from the scope of the present invention, and it should be also understood that the protective scope of the present invention is interpreted by the matters described in the following claims.

Claims

What is claimed is:

1. A door comprising: an outer skin and an inner skin which have concave parts and plane parts, the concave parts being concavely formed to form a pattern and the plane parts respectively formed between the concave parts, the plane parts of the respective outer skin and inner skin all lying in the same plane, the outer skin and the inner skin being spaced apart from each other; frames which form edge portions between the outer skin and the inner skin; an insulating layer formed inside the frames by foaming liquid injected between the outer skin and the inner skin and foamed; a plurality of reinforcing plates made of laminated veneer lumber (LVL) which are mounted between the outer skin and the inner skin to be respectively spaced apart from both of the outer skin and the inner skin, the reinforcing plates also being spaced apart from one another; and supporting means for supporting the reinforcing plates at the positions spaced apart from the outer skin and the inner skin within the insulating layer, wherein the outer skin and the inner skin at the concave parts are relatively thicker than the outer skin and the inner skin at the plane parts.

2. The door according to claim 1, wherein the reinforcing plates are mounted at the plane parts between the concave parts formed on at least one of the outer skin and the inner skin and are separated by the concave parts.

3. The door according to claim 1 or 2, wherein the supporting means are pins of which both end portions are respectively supported inside the outer skin and the inner skin while penetrating through the reinforcing plates.

4. The door according to claim 1 or 2, further comprising: vertical reinforcing frames which are mounted at the central portion where a door knob is mounted, are in contact with the inner surfaces of a vertical frame of the door, have a length in the vertical direction, and are respectively spaced apart from the reinforcing plates.

5. The door according to claim 1 or 2, wherein each of the reinforcing plates has a plurality of through-holes through which the foaming liquid flows.