KR19980068269U - Molding apparatus of shadow mask for cathode ray tube - Google Patents

Abstract

The present invention relates to a shaping apparatus for a shadow mask for a cathode ray tube, and more particularly to a shaping apparatus for a shadow mask for a cathode ray tube that can easily shape the bead portion in a predetermined shape. According to the present invention, a molding apparatus for a shadow mask for a cathode ray tube according to the present invention includes a punch member 10 including a pair of inner and outer punches 12 and 14 and a position corresponding to the punch member 10. And a die member 17 provided with a knock-out portion 18 for shaping the shadow mask and taking out the finished molded product, and a cathode ray is formed by the pressing action of the punch member 10 and the die member 17. An apparatus for forming a shadow mask for cathode ray tubes for molding a conventional shadow mask into a predetermined shape, comprising: a bead molding portion 20a provided on the punch member 10 and a bead molding portion provided on the die member 17 ( 20b) is characterized in that it is configured to be in contact with each other at the time of pressure contact.

Description

Molding apparatus of shadow mask for cathode ray tube

The present invention relates to a shaping apparatus for a shadow mask for cathode ray tubes, and more particularly to a shaping apparatus for a cathode ray tube shadow mask that can be easily formed into a predetermined shape of the bead portion of the shadow mask for cathode ray tubes.

In general, the color water tube (CRT) of cathode ray tubes emits a myriad of red, green, and blue electron beams arranged in a line of red cyan and is deflected through a deflection region formed by a deflection coil. It passes through the hole of the mask and collides with a light emitting body called a phosphor coated on the inner surface of the glass called PANNEL to reproduce the color image.

The exterior of the color water pipe consists of a glass product in which a panel and a funnel are sealed. Is assembled.

The shadow mask has a number of slit holes formed in a thin steel sheet and is molded to match the curvature of the inner surface of the panel. The shadow mask and the frame are assembled to each other by spot welding or electric resistance welding on each of short and long edges. In addition, the distance between the panel and the mask frame assembly, that is, the value of PM-Q, is determined by the welding process of the mask, the frame and the holder and the position of the stud pins.

In addition, a specific relative positional relationship is required between beams regularly arranged in the shadow mask and a beam landing between the corresponding phosphors.

However, due to its operation principle, the color water pipe is less than 1/3 of the cell beam passing through the hole of the shadow mask, and the remaining electron beam is projected around the hole of the shadow mask. In this way, the electron beam projected around the hole of the shadow mask is converted into thermal energy, and the thermal energy is expanded by heating the shadow mask.

As a result, the non-landing position is changed, thereby reducing the color purity of the color water pipe. This phenomenon becomes more severe as the size of the screen becomes larger and higher. Inval shadow mask made of nickel-iron alloy was developed to prevent the color purity degradation of the shadow mask caused by the dope phenomenon.

The Invar shadow mask has a coefficient of thermal expansion of about 1/10 of that of ordinary AK steel, which can reduce the dominant phenomenon of the color water pipe (CRT), thereby exhibiting a favorable effect on thermal expansion. However, due to the addition of nickel, the yield stress is relatively large compared to AK steel, so there is a problem in that the moldability is somewhat reduced. Therefore, conventional AK molding dies cannot be used to form such Invar shadow masks, and the thin sheet material for manufacturing the shadow masks is preheated to a recrystallization temperature in order to mold in a state in which a large yield stress is reduced compared to AK steel. There is a need for a device, which is called a HOT DIE.

On the other hand, unlike the AK molding die, the basic structure of the thermal fiber is that the mold is heated in advance before the molding process of the shadow mask while the heater is inserted into the contact portion (punch, knockout, die, blank holder) of the shadow mask. Is heated to the recrystallization temperature.

1 (a) to 1 (e) are diagrams schematically showing a manufacturing process of a general shadow mask. Referring to FIG. 1, the molding process includes a flat material fixing step of fixing a flat material, a molding step of molding a curvature part and a bead part of the flat material, and a takeout step of taking out the molded shadow mask.

The plane material fixing step of fixing the plane material is provided on the side of the punch member and the die member by lowering the punch member, which is a pressing molding member, as shown in FIG. 1 (a) for fixing the skirt portion of the flat shadow mask. As the pressing member and the supporting member, both side skirt portions of the flat shadow mask of the flake are fixed by the pressing contact of the blank holder. After fixing the planar shadow mask by press-contacting the punch member and the die member, as shown in FIG. 1 (b), the inner punch provided with a curvature portion in contact with the planar shadow mask is lowered to form a die. The curvature of the shadow mask is molded by contacting the upper surface of the knockout portion of the member. After molding the curvature of the shadow mask, as shown in Fig. 1 (c), the outer punch is lowered to the bottom dead center of the molding stroke with the punch member and the die member released from the pressure contact state. The bead part formed can be shape | molded to a predetermined shape. After the molding of the shadow mask is completed through the molding step, the molded shadow mask is taken out by raising the knock-out portion of the punch member and the die member in FIG.

FIG. 1 (e) shows the finished product of the shadow mask which is completed through the fixing step, the molding step, and the extraction step described above. As shown in the figure, the shadow mask is formed to be bent along the outer periphery of the curvature portion and the curvature portion formed with a plurality of slit holes on the surface to be bonded to the panel and pass through the electron beam to support the shadow mask on the panel. It consists of a bead portion that is fixed to the frame for fixing.

During the molding operation of the conventional shadow mask, the bead portion forming operation of the shadow mask by the lowering of the outer punch in the press forming member will be described in detail with reference to FIG. 2. Referring to FIG. 2, a molding apparatus of a shadow mask includes a punch as a press forming member including an inner punch 32 and an outer punch 31 elastically supported by a spring 4 at an outer side of the inner punch 32. PUNCH member 1 and a die member 42 provided at a lower position corresponding to the punch member 1 and provided with a knock-out portion 40 for forming and taking out a flat shadow mask. The shaping and extracting work of the shadow mask is performed.

In addition, a horizontal shadow mask is placed on one end of the punch member 1 and the die member 42 which are in contact with each other when the punch member 1 descends to the die member 42 for pressure contact. The bead shaping | molding part 6a, 6b which has a fixed angle with respect to is provided. Therefore, the bead portion of the shadow mask placed between the die member 42 of the punch member 1 can be formed by the lowering of the outer punch 31.

However, in the conventional shadow mask forming apparatus, the angles θ1 and θ2 formed by the bead forming portion 6a of the punch member 1 and the bead forming portion 6b of the die member 42 with respect to the horizontal plane on which the shadow mask is placed. Is the same. Due to this, as shown in FIG. 3, the line contact is made at the bead forming portions 6a and 6b provided at the distal ends of the punch member 1 and the die member 42 by the lowering of the outer punch 31. During the bead shaping of the shadow mask, the friction force generated at the contact surface tends to increase due to the full length contact of the bead forming portion. In addition, due to stress concentrations occurring at both ends of the bead molding parts 6a and 6b, not only accurate molding is difficult, but also, there is a problem that the shadow mask and mold of the thin metal foil are damaged in severe cases.

Accordingly, the present invention is to solve the above problems, an object of the present invention is to make a different molding angle of the bead molding portion of the upper punch member and the bead molding portion of the lower die member when forming the bead portion of the shadow mask for cathode ray tube The present invention provides an apparatus for forming a shadow mask for a cathode ray tube that can improve molding workability of a shadow mask and can prevent mold damage.

1 (a) to (e) is a view briefly showing a molding process of a general shadow mask,

2 is a simplified view showing a structure of a conventional molding apparatus for a shadow mask;

3 is a view showing briefly the operating state of FIG.

Figure 4 is a simplified view showing a brief forming apparatus of the shadow mask according to an embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

10: punching member 12: outer punch

14: inner punch 16: spring member

17: Die member 18: Knockout part

20a, 20b: Bead molding part

The above object is made of a pressing member for molding the curvature of the shadow mask according to the present invention, and a die member installed to correspond to the pressing member, the shadow by the interlocking action of the pressing member and the die member An apparatus for forming a shadow mask for a cathode ray tube for molding a mask into a predetermined shape, wherein the bead molding portion provided on the press molding member and the bead molding portion provided on the die member are bead molded of the press molding member when they are pressed against each other. It is achieved by the apparatus for forming a shadow mask for cathode ray tube, characterized in that the bead forming portion of the portion and the die member is formed to be in contact with each other.

The bead molding portion of the pressing molding member and the bead molding portion of the die member may be formed different from each other. Preferably, the angle of the bead molding portion provided in the die member is formed larger than the angle of the bead molding portion provided in the pressing molding member.

In addition, it is preferable that a round is formed in the bead molding portion provided in the press molding member and the contact edge portion of the bead molding portion provided in the die member.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 is a view briefly showing the structure of the shadow mask forming apparatus according to the present invention.

Referring to FIG. 4, the molding apparatus according to the present invention includes an inner punch 14 and an outer punch 12 installed while wrapping the inner punch 14 from the outside and elastically supported by each other by a spring member 16. The die member is provided as a pressing member 10 and a punch member 10, which is installed at a lower corresponding position so as to be in close contact with the punch member 10, and has a knock-out portion 18 for supporting and taking out the shadow mask. 17).

The spring member 16 installed between the inner punch 14 and the outer punch 12 not only elastically supports the flat material of the flake at the top when forming the mask material, but also supports the pressing force of the punch member 10 from the inside. It can be buffered to prevent wear of the punch member.

In addition, bead forming portions 20a and 20b are formed in the front end contact portions of the punch member 10 and the die member 17 to shape the bead portion of the shadow mask into a predetermined shape. The bead forming portion (20a, 20b) is configured to be in contact with a predetermined length portion of the bead forming portion during pressing close contact to form a material.

In the present embodiment, the bead forming portion (20a, 20b), the angle (θ1) that the bead forming portion 20a provided on the lower surface of the outer punch of the punch member 10 to the horizontal plane and the die member 17 Contact is made on one side of the flaky material by varying the angle θ2 made by the bead molding portion 20b with respect to the horizontal plane. That is, the angles of the bead molding parts 20a and 20b are provided so as to have a constant difference from each other.

Therefore, when molding the bead portion of the shadow mask due to the lowering of the punch member 10, which is a press molding member, that is, the bead molding is provided on the punch member 10 when the punch member 10 is lowered and comes into contact with the die member 17. The bead molding portion 20b provided in the portion 20a and the die member 17 is in contact with each other on some surfaces. Therefore, when molding the shadow mask, the bead molding parts 20a and 20b are directly molded at the contact part, and indirect molding by plastic deformation is performed on the remaining part of the shadow mask which is the non-contact part. Partial contact of the bead molding portions provided in the punch member 10 and the die member 17 during molding may concentrate the load only on the contact portions of the bead molding portions 20a and 20b to facilitate molding of the flake material.

After the molding is completed, the shadow mask is in contact with the upper surface of the die member 17, so that the shadow mask can be easily separated from the die member 17. In the present embodiment, the angle θ2 of the bead molding parts 20a and 20b provided in the knockout part 17 is larger than the angle θ1 of the bead molding part 20a provided in the outer punch 12. In another embodiment, the angle θ1 of the bead molding portion 20a provided in the punch member 10 is greater than the angle θ2 of the bead molding portion 20b provided in the knockout portion 17. It is also possible.

However, in order to ensure smooth formability, the angle difference between the bead forming portion 20a of the punch member 10 and the bead forming portion 20b of the die member 17 is preferably limited to about 1-5 degrees.

As another embodiment for the partial contact of the punch member 10 and the die member 17, a molding end is provided to protrude from a portion of the bead molding portion provided in parallel with each other to form the punch member 10 and the die member 17. Contact may be made at a portion of the bead forming portion during the pressurized contact for forming.

In addition, the bead forming portion (20a, 20b) is to form a round portion at both edges to prevent the stress concentration tends to occur in the bead molding portion when forming the shadow mask. Other general configuration of the molding apparatus according to the present invention is the same to or similar to the known configuration, the description of the operating relationship for such a portion is omitted.

According to the shaping apparatus for the cathode ray tube shadow mask according to the present invention as described above, it is possible to effectively improve the molding workability of the shadow mask due to the reduction in the contact length in the upper and lower bead molding portion when forming the shadow mask. . The friction force generated when contacting the bead molding portion is reduced, thereby preventing the molding failure of the shadow mask. In addition, the stress generated in the upper and lower bead molding portion is uniformly distributed over the entire length of the contact surface to prevent damage to the mold has the effect of extending the life of the mold.

While the present invention has been shown and described in connection with certain preferred embodiments, it is understood that the present invention may be variously modified, changed, applied, and changed without departing from the spirit or the field of the present invention. Those skilled in the art can easily know.

Claims (3)

Compression molding member 10 for molding the curvature of the shadow mask, and the die member 17 is installed to correspond to the pressing member 10, the pressing member 10 and the die member 17 In the shaping apparatus of the shadow mask for cathode ray tube for shaping the shadow mask into a predetermined shape by the interlocking action of, The bead molding portion 20a of the pressing molding member 10 when the bead molding portion 20a provided on the pressing molding member 10 and the bead molding portion 20b provided on the die member 17 are in close contact with each other. ) And the bead forming portion (20b) of the die member 17 is formed so that the contact can be made in part with each other forming apparatus of the shadow mask for cathode ray tubes. The method of claim 1, wherein the angle of the bead molding portion 20a of the press-molded member 10 and the bead-shaped portion 20b of the die member 17 are formed differently. Molding apparatus. The method of claim 2, wherein the angle of the bead molding portion 20b provided in the die member 17 is formed larger than the angle of the bead molding portion 20a provided in the pressing molding member 10. Molding apparatus for shadow mask for cathode ray tube.