JP2007086407A - Method for manufacturing chassis frame of large-size flat display device, and chassis frame - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-cost manufacturing method with which a lightweight chassis frame with high strength for a large-size flat display device can efficiently be manufactured from raw materials and which is suitable for mass-production. <P>SOLUTION: The method includes: a stage of forming metallic frame members forming four sides of the chassis frame 2 in a nearly rectangular shape; a surface processing stage of processing surfaces of the frame members at least nearby joint parts to form many fine recesses and thus forming joined surfaces; and an injection joining stage of injecting thermoplastic resin to joined surfaces over two frame members which are brought into contact or put close to the respective joined parts and coupling the four frame members in one body to form the chassis frame. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a chassis frame constituting a chassis of a large flat display device such as a large liquid crystal television device, and more specifically, by applying a technique for integrating a metal structure and a thermoplastic resin. The present invention relates to a chassis frame manufacturing method that can manufacture a lightweight and high-strength chassis frame at low cost.

  Conventionally, a chassis of a large flat display device such as a large liquid crystal television device has been created by punching a sheet metal or press forming. However, when it becomes a chassis of a large screen, a large-sized sheet metal material is used, and a core generated by punching out the central portion of the sheet-metal material becomes proportionally large. This core is treated as unnecessary waste material produced during chassis manufacturing. However, the generation of such large waste material itself has a problem in terms of material cost, and the disposal of waste material is also expensive. There was a problem.

A panel type display device as described in Patent Document 1 below is also known. Patent Document 1 describes that four rectangular steel pipes are combined to form a rectangular frame. Square steel pipes are connected by welding or screwing.
JP 2000-92415 A

  If the chassis of a large flat panel display is created by stamping or stamping a large sheet metal material as in the past, there is a problem in terms of material cost and waste material processing cost, and the manufacturing cost cannot be reduced. was there. Further, even with a chassis connected with square steel pipes as described in Patent Document 1, the connection process is not suitable for mass production, and there is a problem that the manufacturing cost cannot be reduced.

  Therefore, the present invention can efficiently manufacture a lightweight and high-strength chassis frame for a large-sized flat display device from a material by applying a technology for integrating a metal structure and a thermoplastic resin, and also for mass production. An object is to provide a suitable low-cost manufacturing method.

  In order to achieve the above object, a method for manufacturing a chassis frame of a large-sized flat display device according to the present invention includes a step of forming a metal frame member that forms four sides of a substantially rectangular chassis frame, and the frame member. Surface treatment step at least on the surface in the vicinity of the joint portion to form a number of micro-recesses to form the joint surface, and the four frame members are arranged in the chassis frame shape in contact with or in close proximity to each other, A thermoplastic resin is injected and joined to the joining surface across the two frame members in contact with or close to each other at each joint, and the four frame members are integrally joined to form the chassis frame. An injection joining step.

  In the method for manufacturing a chassis frame of the large-sized flat display device, the surface treatment step is preferably performed by immersing the frame member in an erodible liquid.

  Moreover, in the chassis frame manufacturing method of the large flat display device described above, it is preferable that an average inner diameter of the minute recesses in the surface treatment step is in a range of 10 to 80 nm.

  In the method for manufacturing a chassis frame of the large flat display device, it is preferable that the thermoplastic resin in the injection joining step is a crystalline resin.

  In the method for manufacturing a chassis frame of the large flat display device, it is preferable that the thermoplastic resin in the injection joining step is a resin mainly composed of polyphenylene sulfide.

  Further, in the chassis frame manufacturing method of the large-sized flat display device, the injection joining step inserts the frame member into an injection mold, and injects and joins the thermoplastic resin to the joining surface. Preferably there is.

  In the method for manufacturing a chassis frame of the large flat display device, the frame member is preferably made of an aluminum alloy.

  Further, the chassis frame of the large-sized flat display device of the present invention includes a step of forming a metal frame member that forms the four sides of the substantially rectangular chassis frame, and at least a surface of the frame member near the joint portion. A surface treatment process is performed to form a large number of minute recesses to form a bonding surface, and the four frame members are arranged in contact with or in close proximity to each other in the shape of the chassis frame, and are brought into contact with or close to each bonding portion. Manufactured by an injection joining process in which a thermoplastic resin is injected and joined to the joining surface across the two frame members, and the chassis frame body is formed by integrally joining the four frame members. It is.

  Further, in the chassis frame of the above large flat display device, the surface treatment step is performed by immersing the frame member in an erodible liquid and performing etching so that the average inner diameter of the minute recesses is in the range of 10 to 80 nm. Thus, it is preferable to perform surface treatment.

  In the chassis frame of the large flat display device, it is preferable that the thermoplastic resin in the injection joining step is a resin mainly composed of polyphenylene sulfide.

  Moreover, in the chassis frame of the large-sized flat display device, the injection joining step inserts the frame member into an injection mold and injects and joins the thermoplastic resin to the joining surface. Is preferred.

  In the chassis frame of the large flat display device, the frame member is preferably made of an aluminum alloy.

  Since this invention is comprised as mentioned above, there exist the following effects.

  Since the chassis frame body is manufactured by integrally joining the metal frame members that form the four sides, the wasteful part of the material is greatly reduced, reducing the material cost and the waste material processing cost. Thus, the manufacturing cost of the chassis can be greatly reduced. In addition, since the frame members are integrally coupled by injection molding using a mold, mass production can be performed, and the manufacturing cost can be further reduced.

  Since the surface treatment of the bonding surface is performed by immersing the frame member in an erodible liquid and performing etching, the process of forming a large number of minute recesses can be easily performed.

  When the surface treatment of the bonding surface is performed so that the average inner diameter of the minute recesses is in the range of 10 to 80 nm, the bond strength between the metal member and the thermoplastic resin can be maximized.

  By using the thermoplastic resin as a crystalline resin, the bond strength between the metal member and the thermoplastic resin can be increased. As the crystalline thermoplastic resin, a resin mainly composed of polyphenylene sulfide can be used.

  Since the frame member is inserted into the injection mold and the thermoplastic resin is injected and joined to the joining surface, mass production is easy and the manufacturing cost can be reduced.

  When the frame member is made of an aluminum alloy, a chassis frame body that is lightweight, has corrosion resistance, and has strong bonding strength with a thermoplastic resin can be manufactured at low cost.

  Embodiments of the present invention will be described with reference to the drawings. First, the chassis structure of a large flat display device will be described together with the prior art. FIG. 7 is a diagram showing the structure of a conventional chassis 10. FIG. 7 is a view of the chassis 10 of the large flat display device as viewed from the screen side. The chassis frame 11 is stamped into a large sheet metal material, and most of the center is punched into a frame shape. Further, it is formed into a step shape by press forming. The cross-sectional structure of the chassis frame 11 is as shown in FIG. 8 is a cross-sectional view taken along line AA in FIG.

  A reinforcing beam member 12 is fixed to the chassis frame 11 as shown. The chassis frame 11 and the beam member 12 are fixed by welding, screwing, or the like. As shown in FIG. 8, the components of the large-sized flat display device are attached to the chassis 10. Here, a large-sized flat display device using the liquid crystal display panel 16 will be described as an example. A support member 13 fixed to the chassis 10 supports a backlight 14 such as a fluorescent tube. A light diffusion plate 15 and a liquid crystal display panel 16 for uniformly diffusing light from the backlight 14 are fixed to the chassis 10. Although not shown in FIG. 7, a member that supports the backlight 14 and a member that supports the light diffusion plate 15 are also fixed to the beam member 12.

  In the chassis frame 11 of the large-sized flat display device, a large-sized sheet metal material is used, and a core generated by punching out the central portion of the sheet-metal material is proportionally large. This core is treated as unnecessary waste material produced during chassis manufacturing. However, the generation of such large waste material itself has a problem in terms of material cost, and the disposal of waste material is also expensive. There was a problem. Therefore, in the present invention, a technology for integrating a metal structure and a thermoplastic resin is applied so that a lightweight, high-strength chassis frame for a large flat display device can be efficiently manufactured from a material. .

  FIG. 1 is a view showing a chassis 1 by a chassis frame 2 manufactured by the manufacturing method of the present invention. The chassis frame 2 is not an integrally formed molded product like the chassis frame 11 shown in FIG. The frame members constituting the upper, lower, left and right sides are joined at the corners. In this joining, a thermoplastic resin is joined to a metal frame member by injection molding, and at the same time, the frame members are joined together. Details of the bonding method will be described later. Since the chassis frame 2 is formed by joining the frame members on the four sides in this way, the waste of the material is greatly reduced without greatly punching the center portion.

  A plurality of beam members 3 are fixed to the chassis frame 2 for reinforcement and support of attachment parts. The fixing method of the chassis frame 2 and the beam member 3 is also the joining by injection molding of a thermoplastic resin similar to the joining of the frame member. All of these fixing points can be joined simultaneously by insert molding, and can be joined in a short time, which is a manufacturing method suitable for mass production.

  Each frame member constituting the chassis frame 2 can use an extruded shape member 20 of an aluminum alloy. FIG. 2 is a view showing the extruded shape member 20. The cross-sectional shape of the extruded shape member 20 is as shown in FIG. FIG.2 (b) is BB arrow sectional drawing in Fig.2 (a). As shown in FIG. 2A, the extruded shape member 20 is cut as indicated by dotted lines to form each frame member.

  FIG. 3 is a view showing the frame members 21 to 24 cut from the extruded shape member 20. The frame member 21 constitutes the upper side, the frame member 22 constitutes the right side, the frame member 23 constitutes the lower side, and the frame member 24 constitutes the left side. As shown in FIG. 3, each frame member 21-24 can be easily created only by cutting at an angle of 45 degrees with respect to the axial direction of the extruded profile 20.

  FIG. 4 is a diagram illustrating a state in which the frame members are attached to each other. In the case of a simple cut at an angle of 45 degrees as shown in FIG. 3, they are attached as shown in FIG. An irregular shape that engages with each other may be formed on the abutting surface of the frame member, and an abutting state as shown in FIG. In the frame members 21b and 24b thus configured, the misalignment of the butted portion is unlikely to occur, and the coupling strength can be further increased. However, sufficient positional accuracy and strength can be obtained even with the shape of the abutting surface as shown in FIG. The same is true for the other frame members.

  As a material of the frame members 21 to 24, an extruded shape 20 of an aluminum alloy is preferable, but a molded product such as a magnesium alloy can also be used. If possible, a material having a linear expansion coefficient as close as possible to the linear expansion coefficient of the thermoplastic resin to be joined is preferable.

  The joining surfaces near the butted portions of the frame members 21 to 24 form a large number of minute recesses by surface treatment. FIG. 5 shows the bonding surface 211 at the end of the frame member 21. The bonding surface 211 can be easily surface-treated by immersing it in an erosive liquid (erosive aqueous solution, erosive suspension) for a predetermined time. It is desirable that the bonding surface 211 be covered with the entire surface by minute recesses or openings having an average inner diameter of 10 to 80 nm.

  For example, in aluminum alloy A5052, when a water-soluble amine aqueous solution is adjusted to a weak basicity of about PH10 and immersed at 40 ° C., a recess with an average inner diameter of 20 to 40 nm is generated immediately and the depth is the same level as the inner diameter in about 1 minute. become. Further, when the immersion is further continued, the depth of the concave portion becomes deeper and the edge portion forming the concave portion is crushed, and the average inner diameter becomes larger and larger.

  When the surface of the A5052 piece immersed for about 20 minutes, washed with water and dried is observed with an electron microscope, the average inner diameter of the recesses visible from the surface is as large as 80 to 100 nm. According to the result of the experiment in which the PPS resin was injected and bonded to the aluminum alloy A5052, the bonding force rapidly decreased in a state where the average inner diameter of the recesses exceeded 80 nm. That is, in the chemical etching by immersing the A5052 aluminum alloy piece in the weakly basic aqueous solution, the joining force in the injection joining rapidly decreased almost at the average inner diameter of 80 nm.

  When the metal erosion progresses to an extent that the average inner diameter of the recess exceeds 80 nm, it is considered that the strength of the metal surface structure is weakened and the bonding force is reduced. From these experimental results, it is preferable that the bonding surface is subjected to a surface treatment so that the average inner diameter of the minute recesses is in the range of 10 to 80 nm. In the surface treatment by immersion in the erodible liquid, the immersion time is adjusted so that the average inner diameter of the minute recesses is in the range of 10 to 80 nm.

  FIG. 5 is a view showing the bonding surface 211 in the vicinity of the butted portion of the frame member 21. The bonding surface 211 is subjected to a surface treatment by immersing it in an erosive liquid (erosive aqueous solution, erosive suspension) for a predetermined time, so that the surface is covered with a large number of minute recesses. The processing time is set so that the average inner diameter of the minute recesses is 10 to 80 nm. In the figure, only the joining surface 211 at one end of the frame member 21 is shown, but the joining surface 211 subjected to the same surface treatment is also formed at the other end. In addition, the same surface treatment is performed on the joining surfaces of both end portions of the other frame members 22 to 24 and the joining surfaces joining the frame members 21 and 23 and the beam member 3.

  The surface treatment may be performed only on the joint surfaces in the vicinity of the joint portions of the frame members 21 to 24 and the beam member 3, but the entire frame members 21 to 24 and the beam member 3 are immersed in an erodible liquid. Then, surface treatment may be applied to the entire surface. The surface treatment should just be given to the joining surface of the junction vicinity at least.

  Each member that has been surface-treated to form micro-recesses on the bonding surface is inserted into a mold and injection molding of a thermoplastic resin is performed, and each member is also firmly bonded to each other by the strong bonding between each member and the resin. Be joined. FIG. 6 shows a joint portion of the frame members 21 and 24 in the injection molding process. The frame members 21 and 24 are inserted into the molds 6 and 7 in a state of being butted. A gate 71 is formed on the mold 7 side in the vicinity of the butted portion of these frame members. The thermoplastic resin 25 is injected from the gate 71 and firmly joined to the joining surfaces of the frame members 21 and 24. Thereby, frame members 21 and 24 are also joined firmly. The same applies to the joints of other members.

  In addition, it is desirable to form various support portions, a holding structure, and the like on the frame members 21 to 24 and the beam member 3 by injection molding of a thermoplastic resin simultaneously with the joining of the respective members. For example, a support portion and a holding structure such as a backlight, a light diffusion plate, and a liquid crystal display panel can be formed. A joining surface for joining the thermoplastic resin is provided at a position where each member is formed. These bonding surfaces are covered with a large number of minute recesses having an average inner diameter of 10 to 80 nm by the same surface treatment as described above.

  Although FIG. 6 shows an example in which the frame members 21 and 24 are arranged in contact with each other, it is not always necessary to place the members in contact with each other, and the members are arranged close to each other. You may do it. When the members are arranged close to each other, the thermoplastic resin flows into the gaps between the members and firmly joins the members. In this case, the surface facing the gap between the members is also a bonding surface in which minute concave portions are formed by surface treatment.

  The thermoplastic resin that is injected and bonded to the bonding surface of each member is preferably a crystalline resin. When a crystalline resin is used, the bonding strength between the resin and each metal member is greatly increased. Examples of the crystalline thermoplastic resin include a resin mainly composed of polyphenylene sulfide (PPS).

  The injection molding process shown in FIG. 6 will be described. First, the molds 6 and 7 are opened, and a metal member provided with a joining surface as described above is inserted into one of the molds 6 and 7, the molds 6 and 7 are closed, and 70 to 99% by weight of PPS resin and 30 to 1 polyolefin resin are used. The chassis frame body 2 and the chassis 1 are manufactured by injecting and solidifying a thermoplastic resin composition having a resin component composition containing% by weight and then releasing the mold.

  The feature of the injection condition in the present invention is that the molten resin comes into contact with the metal part inserted at high temperature and pressure. In that sense, there are some differences from general injection molding. That is, it is desirable to raise the mold temperature slightly. Specifically, it is preferably 100 ° C. or higher, more preferably 120 ° C. or higher. On the other hand, the injection temperature, injection pressure, and injection speed are not particularly different from ordinary injection molding.

The steps of the production method of the present invention described above are summarized as follows (1) to (3).
(1) Step of cutting the extruded shape member 20 to form the frame members 21 to 24 (2) Surface treatment is performed on the resin joint portions of the frame members 21 to 24 to form minute recesses having an average inner diameter of 10 to 80 nm. Step (3) of forming a large number of bonding surfaces Insert the frame members 21 to 24 into the mold, and inject thermoplastic resin onto the bonding surfaces of the frame members 21 to 24 to integrally bond the four frame members. Process

  By manufacturing the chassis frame 2 through these steps, the portion of the material that is wasted is greatly reduced, so the material cost and the waste material processing cost can be reduced, and the chassis manufacturing cost can be greatly reduced. it can. In addition, since the frame members are integrally coupled by injection molding using a mold, mass production can be performed, and the manufacturing cost can be further reduced.

  In the above description, a case where a liquid crystal panel is used as a large-sized flat display device has been described as an example. However, the present invention is not limited to a large-sized flat display device using a liquid crystal panel. The present invention can also be applied to a display using any display panel.

It is a figure which shows the structure of the chassis 1 by this invention. It is a figure which shows the extrusion shape member. It is a figure which shows the frame members 21-24 cut | disconnected from the extrusion shape member 20. FIG. It is a figure showing the state where frame members were put together. FIG. 3 is a view showing a bonding surface 211 in the vicinity of a butted portion of the frame member 21. It is a figure which shows the junction part of the frame members 21 and 24 in an injection molding process. It is a figure which shows the structure of the conventional chassis. It is an expanded sectional view which shows the cross-section of the conventional chassis 10. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Chassis 2 Chassis frame 3 Beam member 6,7 Mold 10 Chassis 11 Chassis frame body 12 Beam member 13 Support member 14 Backlight 15 Light diffusing plate 16 Liquid crystal display panel 20 Extruded member 21, 22, 23, 24 Frame member 25 Thermoplastic resin 71 Gate 211 Bonding surface

Claims (12)

Forming metal frame members (21 to 24) that form four sides of a substantially rectangular chassis frame (2);
A surface treatment step of performing surface treatment on at least the surface of the frame member (21 to 24) in the vicinity of the bonding portion to form a number of minute recesses to form the bonding surface (211);
The four frame members (21 to 24) are arranged in the shape of the chassis frame (2) in contact with or close to each other, and straddle the two frame members (21 to 24) in contact with or close to each other at each joint. An injection joining step of injecting a thermoplastic resin to the joining surface (211) and joining the four frame members (21 to 24) integrally to form the chassis frame (2). A method for manufacturing a chassis frame of a large flat display device. A chassis frame manufacturing method for a large-sized flat display device according to claim 1,
The said surface treatment process is a chassis frame body manufacturing method of the large sized flat display apparatus which immerses the said frame member (21-24) in an erodible liquid, and performs an etching. A chassis frame manufacturing method for a large-sized flat display device according to claim 2,
The method for manufacturing a chassis frame of a large flat display device, wherein an average inner diameter of the minute recesses in the surface treatment step is in a range of 10 to 80 nm. It is a chassis frame manufacturing method of the large sized flat display device given in any 1 paragraph of Claims 1-3,
The said thermoplastic resin in the said injection | emission joining process is a chassis frame body manufacturing method of the large sized flat display apparatus which is crystalline resin. A chassis frame manufacturing method for a large-sized flat display device according to claim 4,
The said thermoplastic resin in the said injection | emission joining process is a chassis frame body manufacturing method of the large sized flat display apparatus which is resin which has polyphenylene sulfide as a main component. It is a chassis frame manufacturing method of the large sized flat display device given in any 1 paragraph of Claims 1-5,
In the injection joining step, the frame member (21-24) is inserted into an injection mold (6, 7), and the thermoplastic resin is injected and joined to the joining surface (211). A method for manufacturing a chassis frame of a display device. A chassis frame manufacturing method for a large flat display device according to any one of claims 1 to 6,
The said frame member (21-24) is a chassis frame manufacturing method of the large sized flat display apparatus which consists of aluminum alloys. Forming metal frame members (21 to 24) that form four sides of a substantially rectangular chassis frame (2);
A surface treatment step of performing surface treatment on at least the surface of the frame member (21 to 24) in the vicinity of the bonding portion to form a number of minute recesses to form the bonding surface (211);
The four frame members (21 to 24) are arranged in the shape of the chassis frame (2) in contact with or close to each other, and straddle the two frame members (21 to 24) in contact with or close to each other at each joint. An injection joining step in which a thermoplastic resin is injected and joined to the joining surface (211), and the four frame members (21 to 24) are integrally coupled to form the chassis frame (2). The chassis frame of the manufactured large flat panel display. It is a chassis frame of the large sized flat display device according to claim 8,
In the surface treatment step, the frame member (21 to 24) is immersed in an erodible liquid for etching, and the surface treatment is performed so that the average inner diameter of the minute recesses is in the range of 10 to 80 nm. Chassis frame for large flat panel display. A chassis frame for a large flat panel display device according to any one of claims 8 and 9,
The said thermoplastic resin in the said injection | emission joining process is a chassis frame body of the large sized flat display apparatus which is resin which has polyphenylene sulfide as a main component. It is a chassis frame of the large sized flat display device given in any 1 paragraph of Claims 8-10,
In the injection joining step, the frame member (21-24) is inserted into an injection mold (6, 7), and the thermoplastic resin is injected and joined to the joining surface (211). Chassis frame of the display device. It is a chassis frame of the large sized flat display device given in any 1 paragraph of Claims 8-11,
The frame member (21 to 24) is a chassis frame body of a large-sized flat display device made of an aluminum alloy.

Images