CN85101993B - Method of punching corrugated shielding plate for color television kine scope and its apparatus - Google Patents

Abstract

A shielding plate composed of iron-nickel alloy of a color kinescope is punched by a punching technology. In the process of punching, the temperature of the shielding plate is kept between 150 DEG C and 200 DEG C. The yield limit of the shielding plate materials reaches 0.2 % at the temperatures between 150 DEG C and 200 DEG C under the tensile stress of 150 N/mm<2>.

Description

The method of punching corrugated aperture mask plate

The present invention relates to Sheet Metal Forming Technology is a kind of method of the planar mask of colored visualization tube portion stretching Fe-Ni alloy formation.

Chromoscope has a shell that has a glass developing window usually, and this developing window has the imaging screen of the fluorescence coating that can send red, green, blue coloured light.The planar mask that has a lot of apertures is assemblied in the picture tube, and is very short apart from the distance of imaging screen front end.At the picture tube duration of work, in picture tube, send three strands of electronics by an electron gun system, and the aperture that passes on the planar mask impacts on the above-mentioned fluorescence coating.The mutual position of aperture and fluorescence coating be make scanning picture on each beam electrons bundle always impact on a kind of fluorescence position of color.Yet, there is the electron beam of suitable vast scale to impact on the planar mask, the kinetic energy of electronics has become heat energy, and the temperature of planar mask is risen.Along with temperature rises, planar mask will thermal expansion, thereby cause making the local or whole projection of planar mask, has consequently upset the mutual alignment at aperture on the planar mask and the fluorescence position relevant with these apertures, thus the color defect of generation display frame.Because in the picture tube of current production, the developing window is more flat, makes planar mask projection few, and the display frame defective of enameling is just more serious like this.

Know, make planar mask with the material of low thermal coefficient of expansion and can make the problem of fuel factor generation obtain mitigation.An example of this material is exactly a Fe-Ni alloy, wherein, calculates by weight, and nickel content accounts for 36% greatly.These tensile strength of alloys are than higher, and machining is difficulty relatively, and this has just hindered them as the planar mask material.The machining difficulty of above-mentioned material also makes the used tool wear of punching press planar mask very fast.Yet, because the loss of stamping tool has reduced the reproducibility of Sheet Metal Forming Technology.Thereby the quick loss of instrument just requires to liquidate, and press tool tightens control and often maintenance.In punching course, having a part around planar mask at least is when supporting with sliding type, and this problem is just more outstanding.Because planar mask is just to stand punching course after portalling making, be different in the tensile strength of orthogonal both direction upper plate.In order to prevent that planar mask is washed into fragment along the low direction of tensile strength, it should come clamping in the mode that can slide a little on the low direction of tensile strength in punching course.The frictional force that produces in the slip should be reproduced out quantitatively, so that obtain a repeatably punching course.Because friction is big, has encouraged wearing and tearing, the friction that produces with playback system just no longer exists, and consequently the reproducibility of punching course has also reduced.

Task of the present invention provides the method for a punching press planar mask, and in this method, it is minimum that the wearing and tearing of stamping tool are reduced to, and make the reproducibility of punching course good.Another task of the present invention provides an equipment that uses this method.

According to the present invention, method with the Sheet Metal Forming Technology planar mask that to be the local punching press of chromoscope be made of Fe-Ni alloy, it is characterized in that during punching course planar mask remains between 150 ℃ to 250 ℃ in the temperature range, planar mask material yield limit in this temperature range reaches 0.2%, and this moment, tension was lower than 150N/mm ²

Improve temperature and come the punching press planar mask, the tension that the planar mask material reaches its 0.2% yield limit has descended.The known tension of working as approximately is no more than 150N/mm ²The time, the situation of stamping tool wearing and tearing and the reproducibility of punching course can be in gratifying level.The invention enables the Fe-Ni alloy might be, and might utilize the extremely low advantage of these alloy thermal coefficient of expansions as the material of planar mask.For this consideration, specially suitable a kind of alloy is the nickel that contains 35-37% weight, and all the other all are iron outward to remove small amount of impurities.According to the present invention, characteristics are to stand the annealing in process of a period of time between 700 ℃ to 820 ℃ at planar mask before the punching course more specifically, make the material of planar mask produce crystallization more fully.Annealing in process has two purposes.First purpose is to make material produce crystallization more fully, so that make the punching press character of whole planar mask be tending towards even.Second purpose is that the tension of material under 0.2% yield limit is reduced near 300N/mm ²

Have been found that for perfect recrystallization the temperature of annealing in process must be finished being higher than under about 700 ℃ temperature.Concerning cold rolling this material, the tension that also makes 0.2% yield limit is toward descending clearly, and when using higher annealing temperature, this tension further descends, but has been found that it is rational that annealing in process is forced a ceiling temperature.According to the present invention, this ceiling temperature approximately is 820 ℃.In the temperature range between 700 ℃ to 820 ℃, 0.2% yield limit descends with the rising of temperature.Therefore in order further in usable range, to reduce by 0.2% yield limit, be necessary apparently higher than 820 ℃ annealing temperatures.Yet, under 820 ℃ temperature, allow the form annealing of planar mask to stack, do not stick together the thermo-molecular welding and can not resemble.

What Fig. 1 represented is the relation of Fe-Ni alloy tensile strength and annealing temperature.

Fig. 2 represents is the relation of moving back the Fe-Ni alloy that overdoes its tensile strength and temperature during local punching press.

Fig. 3 is the profile of the equipment of punching press planar mask.

For nickel by 36% weight, the carbon that is less than 0.04% weight is less than the silicon of 0.3% weight, is less than the magnesium of 0.5% weight, all the other are Fe-Ni alloys that iron is formed, and it is the tensile stress value that was reached in 0.2% o'clock in yield limit under each annealing temperature and under this temperature that Fig. 1 expresses material.Raw material are the sheet material that is obtained by cold rolling, and thickness is the 100-150 micron.The hole grid are made with the photetching method.According to designing requirement, there is shape arbitrarily in these holes, as groove shape or circle.Behind these holes of etching, the raw material plate that has etched tear line is divided into some, and each sheet constitutes a planar mask and has the hole grid.The planar mask material that obtains so at room temperature, it is at about 600N/mm ²Be 0.2% with yield limit under the tension.Such tensile strength is too high, so that can not strike out designed shape to planar mask.In order to reduce this tension, planar mask need be about 750 ℃ annealing temperature 15 minutes.Make material perfect recrystallization.As shown in Figure 1, the material of Chu Liing like this, its 0.2% yield limit drops to about 300N/mm ²Even in order to guarantee to make 0.2% yield limit of whole planar mask, perfect recrystallization is necessary.From Fig. 1 also as can be seen, in 700 ℃-800 ℃ temperature range, 0.2% yield limit temperature dependency rises with temperature and obviously descends.Further reduce by 0.2% yield limit and need higher annealing temperature.Not only consider, and with the problem of planar mask to exist in the form annealing of stacking, this all is imperfect from the angle of energy.Be higher than under 820 ℃ the temperature, planar mask may since the effect of thermo-molecular welding be welded in together.Yet 300N/mm ²0.2% yield limit remain too high so that can not reprocess the punching press planar mask.For this reason, it is necessary further reducing by 0.2% yield limit.In order to achieve this end, planar mask not at room temperature but does not carry out local punching press between 150 ℃ to 250 ℃.Fig. 2 shows the temperature variation curve of the tension of 0.2% yield limit.The temperature dependency of 0.2% yield limit obviously descends with the temperature rising in 150 ℃ to 250 ℃ temperature range.About more than 250 ℃, 0.2% yield limit rate of descent is quite little greatly.Yet under high like this temperature, begin to work about the practical problem of stamping tool, and no longer the advantage of 0.2% low yield limit is considered.

Fig. 3 is the profile of local punching press planar mask equipment, and it is axle that this equipment has the used sometimes term of stamping die 1(), the pressure rings 2(term of usefulness sometimes is the pleat folder) and punching press ring 3.The planar mask 6 of rectangle is placed on the stamping die 1, and punching press ring 3 is vertically downward towards pressure rings 2 motions.The result is sandwiched between punching press ring 3 and the pressure rings 2 plate 6 relative two edges.On another opposite side of rectangle, leave the gap between punching press ring 3 and the pressure rings 2, this gap is greater than the thickness of planar mask 6.This gap can make planar mask slide in punching course, and the size in gap has been determined the frictional resistance that is produced.In this case, planar mask perpendicular to the tension on the direction of the rectangle side that is provided with the rigidity clamping less than perpendicular to by the tension on the side directions of rigidity clamping.Such gap can obtain with the suitable punching press ring and/or the shape of pressure rings.With four missing links formation punching presses and/or pressure rings also is possible.Each missing link is corresponding to a limit of planar mask.Punching press ring 3 and the pressure rings 2 of descending simultaneously just struck out required conisphere shape to planar mask.This planar mask just is flushed on the stamping die 1 like this.In punching course, the temperature of planar mask remains on 200 ℃.In order to achieve this end, stamping die 1 has a copper billet 7, and heating 8 is arranged in copper billet 7.Similarly, pressure rings 2 also has the copper billet 4 that contains heating 5, and the copper billet 10 that contains heating 11 is also arranged on the punching press ring 3.Planar mask 10 can be heated to 200 ℃ stamping tool heating.Yet, also can in stove, be heated to about 200 ℃ temperature to it in advance.In order to keep in the punching course temperature of whole planar mask even, stamping die 1 has one group of heating duct 9, and it can guarantee the equilibrium of stamping die surface temperature.After planar mask was stamped into conisphere shape, four rectangular edges around it had been bent to form a skirt section.This is because the further decline of punching press ring causes, and just no longer has been clipped between pressure rings and the punching press ring around certain planar mask at this moment.During forming the skirt section around the planar mask, push rod 12 withstands on planar mask on the stamping die 1.This push rod also has the copper billet 13 that contains heating 14, so that planar mask is contacted with the push rod that also is heated to 200 ℃.After the planar mask skirt section formed, push rod left planar mask.Stamping die 3 and planar mask move upward then.Planar mask is ejected in punching press ring 3 by push rod 12 at last, removes then.

Note, do not express the member of operating punching press ring 3, pressure rings 2 and push rod 12 at Fig. 3, this is because they do not have direct relation with the present invention.

Claims (2)

1, a kind of is the part drawing process of the planar mask of colored visualization pipe manufacturer Fe-Ni alloy formation by means of Sheet Metal Forming Technology, it is characterized by before stretching, planar mask is annealed under 700 ° to 820 ℃ temperature, significant increase does not take place again for enough making planar mask produce perfect recrystallization crystal grain in annealing time, and in drawing process planar mask is remained under 160 ℃ to 250 ℃ the temperature and make 0.2% yield limit of planar mask material be lower than 150N/mm ²Tension.

2, the method for claim 1, the composition that it is characterized in that Fe-Ni alloy contains the nickel by 35-37% weight, removes outside the small amount of impurities, and remainder is an iron.

Images