JPH03214543A - Manufacture of glass stem - Google Patents

Abstract

PURPOSE:To form a required header with a single unit of stem fabricating device and allowing formation on a stem continuously by expanding the top of ring-shaped header into a trumpet form prior to formation of the stem, and enlarging the gap between the top of the header and each lead. CONSTITUTION:A ring-shaped glass header 53 is heated and softened, and its top is expanded into a trumpet form. Now the gap between the header top and each lead 3 is enlarged, and the top of the header 53 is no more likely to tumble to the lead side, so that the glass is precluded from attaching to elsewhere than that part necessary for airtight sealing of the lead 3. The softened header 53 can be welded to the lead 3 certainly by pressing a roller 41 thereafter to the periphery of the header. Thus a header in specified form can be formed with a single unit of stem fabricating device along with formation of the stem without use of nay header forming device proprietary for the purpose.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method for manufacturing a glass stem used in an electron tube such as a cathode ray tube.

(Prior Art) Glass stems are generally used in electron tubes such as cathode ray tubes. This glass stem, as shown in Figure 7,
A structure in which an exhaust pipe (2) is welded to the center of a disk-shaped flare (1) made of glass, and a plurality of leads (3) are hermetically planted around this exhaust pipe (2). is formed. Each lead (3) consists of an outer pin (4) extending in the same direction as the exhaust pipe (2), and an inner lead (5) extending in the opposite direction. Also,
A fillet (6) integral with the flare (1) is formed protruding around each inner lead (5).

As a manufacturing method of this glass stem, Japanese Patent Application Laid-Open No. 63-17
As shown in Japanese Patent No. 8430, there is a method in which a glass header to be a flare is formed in advance and a stem is formed using the formed glass header.

That is, in this manufacturing method, a ring-shaped glass header material is heated and softened in advance, and its height is lowered using a mold, so that the inner circumferential surface becomes flower-shaped, as shown in FIGS. 8(a) to (C). A ring-shaped header (8a) with a star shape, a ring-shaped header (8b) with a star-shaped outer circumferential surface, or a ring-shaped header (8c) with a plurality of small holes (9) formed in the middle, etc. A glass header (8) is molded in a shape that matches the arrangement of the leads during stem molding. And the ninth
As shown in the figure, the lower jig (l1) of the stem molding die has a recess (10) for molding the stem on its upper end surface.
Insert the exhaust pipe (2a) into the exhaust pipe insertion hole (13) provided at the center of the bottom surface (12) that forms the molding surface, and insert the lead (2a) into the plurality of lead insertion holes provided around the exhaust pipe insertion hole.
3) and then the above header (8) on the bottom surface (12).
) and heat them to soften one end of the exhaust pipe (2a) and the header (8). Next, lower jig (1
1) is combined with an upper jig (I5) provided with a lead insertion hole (14) corresponding to the lead insertion hole of this lower jig (11), and the softened exhaust pipe (2a) is removed. The stem is formed by pressing one end and the header (8) to spread the header (8) into the recess (10) of the lower jig (1l).

(Problem to be solved by the invention) As described above, as a manufacturing method for glass stems used in electron tubes such as cathode ray tubes, a header of a predetermined shape with a low height is molded in advance, and this header is molded when molding the stem. Place it together with the exhaust pipe and lead in the lower jig of the molding die. Then, heat and soften one end of the exhaust pipe and the header. Combine the upper jig with the lower jig and soften the header. There is a method of forming the stem by pressing one end of the exhaust pipe and the header.

This method of manufacturing a glass stem secures the amount of glass necessary for molding the flare part and also reduces the height of the header, so that when molding the stem, the glass in the header reaches the specified level required for hermetically sealing the lead. Therefore, the wiring connecting the inner lead and the electrode of the electron gun can be stably welded, and it can also be used to prevent the header glass from adhering to other parts than the specified part required for airtight sealing of the inner lead. It has the advantage of being able to prevent the occurrence of progressive cracks that tend to occur.

However, with this glass stem manufacturing method, the header must be made to a predetermined height and molded into a shape that matches the lead placement, so a dedicated header molding device is required in addition to the stem manufacturing device. As a result, equipment costs will increase. Further, when molding the stem, it is necessary to arrange the header in accordance with the arrangement of the leads, and there is a problem in that the positioning is not easy.

This invention was made to solve the above-mentioned problems, and does not require a dedicated header molding device.
It is an object of the present invention to provide a method that allows a required header to be molded using one stem manufacturing device and then to be molded into a stem.

[Structure of the Invention] (Means for Solving the Problems) In a method for manufacturing a glass stem, an exhaust pipe is inserted into an exhaust pipe insertion hole of a lower jig of a stem molding die, and an exhaust pipe is provided around the exhaust pipe insertion hole. A process of inserting multiple leads into the multiple lead insertion holes provided, and arranging a ring-shaped glass header to surround the multiple leads, and inserting the header placed in the lower jig. a step of heating and softening, rotating the lower jig, and forming a header having a tapered surface with a smaller diameter at the tip and a plurality of lead insertion holes corresponding to the lead insertion holes of the lower mold; a step of pressing a molding die against the heated and softened header while rotating in synchronization with the lower mold to expand the upper end of the header into a trumpet shape by the tapered surface, and expanding the upper end into a trumpet shape; A process of heating and softening the header and rolling the upper end side to the outside of the header to lower the height of the header, and rotating the lower jig to roll the outer peripheral surface of the header with the lowered height. A process of pressing a rotating roller to push the heated and softened header inward and welding the header to the plurality of leads, and one end of the exhaust pipe inserted into the exhaust pipe insertion hole of the lower jig. The present invention is characterized by comprising a step of heating and softening the header welded to the part and the lead, and then combining the lower jig with the upper jig of the stem molding die to form the stem.

(Function) As mentioned above, the ring-shaped glass header is heated and softened.
When the upper end of the heated and softened header is expanded into a trumpet shape, the gap between the upper end of the header and the leads becomes larger, and the upper end of the header is prevented from falling toward the leads.
Glass can be prevented from adhering to areas other than those required for hermetically sealing the lead.

Further, by subsequently pressing the outer circumferential surface of the header with a rotating roller, the heated and softened header can be reliably welded to the leads, and a stem with good quality can be manufactured.

(Example) Hereinafter, the present invention will be described based on an example with reference to the drawings.

FIG. 2 shows a stem manufacturing apparatus according to one embodiment. This stem manufacturing device has a rotary table (
21) is arranged, and this rotary table (21) is used as a base (
It has a structure in which it is intermittently rotationally driven by a drive device (22) installed in the main body (20). This rotary table (2l
), as shown in FIG. 3, a plurality of lower jigs (23) of the stem molding die are arranged at equal intervals.

As shown in FIG. 4, each of the lower jigs (23) has a recess (24) formed in the upper end surface for molding the glass stem, and an exhaust pipe insertion hole in the center of the bottom surface (25) of the recess. (2
6), a plurality of lead insertion holes (27) are further formed around this exhaust pipe insertion hole (26).

The glass stem is molded through a loading stage, a heating stage, a molding stage, an annealing stage, and an unloading stage in order while the rotary table (2l) rotates once intermittently. Especially its heating, molding,
Each stage of annealing has at least two or more lower jig stopping positions in order to perform the required molding process and sufficient annealing.

A supply device (not shown) is disposed on the loading stage to supply stem materials such as a glass exhaust pipe, a lead, and a ring-shaped glass header to the lower jig (23) stopped on this stage. There is.

In addition, burners (not shown) for heating the material supplied to the lower jig (23) are arranged at each lower jig stop position on the heating stage, and further process the header that has been softened by heating. A header forming device (29) is arranged at one lower jig stop position, and a header pushing device (30) is arranged at another adjacent lower jig stop position.

The header forming device (29), as shown in FIG.
A tapered surface (3l) is formed in the periphery of the end face opposite to the lower jig (23) located at the lower jig stop position, and each lead of the lower jig (23) is formed with a tapered surface (3l) that reduces the diameter of the end face. A plurality of lead insertion holes (32) corresponding to the insertion hole (27)
) has a molding die (33) formed therein.

This molding die (33) is coaxially attached to a rotating shaft (35) rotatably supported by a support (34).

Then, the support body (34) is fixed to the slide shaft (37) of the elevating mechanism (36) installed on the base body,
The molding die (33) is configured to move toward and away from the lower jig (23) which is stopped at the lower jig stop position as the slide shaft (37) moves up and down. Further, the rotating shaft (35) engages with a pawl (38) provided on the lower jig (23) to engage with the molding die (33).
) is attached to a synchronization lever (39) that rotates the lower jig (23) in synchronization with the rotation of the lower jig (23).

As shown in FIG. 6, the header pushing device (30) has a disc-shaped roller (41) located on the side of the header formed by the header forming device (29).

This roller (4l) is attached to a rotating shaft (43) rotatably supported by a support (42), and
motor (44) fixed to l) and this motor (44)
Gears (45a) and (4) that transmit the rotational torque of (4)
It is designed to be rotationally driven by a drive mechanism consisting of 5b).

Further, the support body (42) is attached to a slider (48) of a slide mechanism (47) provided on a column (46) erected on the base, and the slider (48) is attached to the slider (48) by a drive mechanism (not shown). By sliding the roller (48), the roller (41) is moved toward and away from the header formed by the header forming apparatus.

The molding stage also includes a burner (not shown) that heats each of the above-mentioned materials, as well as a lower jig located at the lower jig stop position of the molding stage to mold the stem as shown in Figure 4. An elevating mechanism (not shown) is arranged to move the upper jig (49) of the shown molding die toward and away from the lower jig. In addition, the upper jig (49) has a plurality of lead insertion holes (50) corresponding to each lead insertion hole (27) of the lower jig (23) and a fillet forming hole (51) for forming the fillet of the stem coaxially. A protrusion (52) forming one end of the exhaust pipe is formed in the center.

Further, the annealing stage includes a heating device (not shown) consisting of a burner etc. for annealing the formed stem, and the unloading stage includes a heating device (not shown) for annealing the formed stem. A transfer mechanism (not shown) for transferring to another device is arranged.

A glass stem is manufactured using this stem manufacturing apparatus as follows.

First, as shown in FIG. 1(a), the lower jig (2
Insert the glass exhaust pipe (2a) into the exhaust pipe insertion hole (2B) of 3> and the lead (3) into each of the plurality of lead insertion holes (27), and insert the lead (3) so as to surround this lead (3). A ring-shaped glass header (5) is placed inside the recess (24).
3) Place. The lower jig (23) supplied with each stem material is rotated intermittently by the rotary table (21).
Move to the next heating stage.

In the heating stage, first, each stem material supplied to the lower jig (23) is heated by a burner placed at the lower jig stop position while rotating the lower jig (23). Then, at the lower jig stop position where the header molding device is located, as shown in FIG. 1(b), the molding die (3
3) is lowered toward the lower jig (23), and the synchronization lever attached to the rotating shaft of this molding die (33) is engaged with the claw provided on the lower jig (23). While rotating the molding die (33) in synchronization with the lower jig (23), press the tapered surface (3I) of the molding die (33) against the header (53) softened by the heating, and press the upper end thereof. The part expands into a trumpet shape. In this case, the lead (3) inserted into the lead insertion hole of the lower jig (23) is inserted into the molding die (
33) into the lead insertion hole (50).

Thereafter, the molding die (33) is raised, and the header (53) expanded into a trumpet shape is heated with a burner, so that the upper end portion expanded into a trumpet shape is heated as shown in FIG. 1(C). The ring-shaped header (53) is rolled outward from the header (53) and is first supplied to the lower jig (23).
3) The height is made lower as shown by h2 than the height h1 (h2<h,). (See Figure 1(a)) Next, at the lower jig stop position where the header pushing device is located, as shown in Figure 1(d), lower the lower jig (23) and rollers (41). While rotating
The drive mechanism slides the slider of the header pushing device, and the roller (4l) is applied from the radial direction to the side of the header (53) whose height has become lower due to the rolling.
Press to push the header (53), which has softened due to heating, inward, and insert it into the lead insertion hole (27) of the lower jig (23).
Weld the lead (3) inserted in the lead (3) so as to surround it. In this case, the rotation speed of the roller (41) is adjusted by the lower jig (
23) In other words, it is preferable to push it in gradually in accordance with the rotational speed of the header (53).

Next, the lower jig (23) is moved to the lower jig stop position of the molding stage by intermittent rotation of the rotary table.

In this forming stage, while rotating the lower jig (23), each stem material including the heel (53) processed by the header forming device and the header pushing device is heated by a burner, and the header (53) and One end of the exhaust pipe (2a) protruding above the lower jig (23) is softened. After that, the upper jig (49) of the molding die is lowered by the lifting mechanism arranged on this molding stage,
As shown in FIG. 1(e), the upper jig (45) and the lower jig (23) are combined and the softened header (5
3) and one end of the exhaust pipe (2a) to form one end of the exhaust pipe (2a), and also press the header (5).
3) is spread into the recess (24) of the lower jig (23) and formed into a stem.

The molded stem is then moved to the lower jig stop position of the annealing stage by intermittent rotation of the rotary table, and while the lower jig is rotated, the molded stem is heated and annealed with a parner. Thereafter, it is moved to an unloading stage, and is taken out from the lower jig by a transfer mechanism disposed on this unloading stage, and transferred to another device.

By the way, when a glass stem is manufactured by the above method,
By expanding the upper end of the ring-shaped header into a trumpet shape before forming the stem and increasing the gap between the upper end of the header and the leads, the upper end of the header will not fall toward the leads, and By lowering the height of the header by rolling it by heating and softening, it is possible to prevent the leads from adhering to areas other than those required for hermetic sealing. Moreover, the header can be reliably welded to the leads by subsequent pushing in the radial direction.

Therefore, unlike conventional glass stem manufacturing methods, there is no need to use a dedicated header molding device to lower the height of the header in advance and mold it into a shape that matches the lead placement during stem molding. In addition, there is no need to position the molded header according to the arrangement of the leads, and a single stem manufacturing device can mold a header of the desired shape from a ring-shaped header and mold the stem, resulting in efficient quality control. A good stem can be manufactured.

[Effect of the invention] An exhaust pipe, multiple leads, and a ring-shaped glass header are arranged to surround the multiple leads in the lower jig of the stem molding die, and the tip is tapered before stem molding. The upper end of the ring-shaped header is expanded into a trumpet shape using a flat header mold, and then the upper end is rolled to the outside of the header to reduce the height of the header, thereby airtightly sealing the leads. This prevents the product from adhering to areas other than those required. Furthermore, by pressing a rotating roller from the radial direction on the outer circumferential surface of the header, which has a reduced height dimension, and pushing the header inward, the header can be reliably welded to the leads, which is a conventional manufacturing method for glass stems. By using a dedicated header molding machine, there is no need to lower the height of the header in advance and mold it into a shape that matches the lead placement during stem molding. There is no need for positioning according to the arrangement, and a single stem manufacturing device can mold a header of the desired shape from a ring-shaped header and mold the stem, making it possible to efficiently manufacture stems of good quality. .

[Brief explanation of drawings]

Figures 1 to 6 are diagrams for explaining embodiments of the present invention, and Figures 1 (a) to (e) are diagrams for explaining a method of manufacturing a glass stem, which is one embodiment of the invention. , FIG. 2 is a diagram showing the configuration of the stem manufacturing apparatus used for manufacturing the glass stem, FIG. 3 is a plan view showing the arrangement of the lower jig of the stem molding die on the rotary table, and FIG. A diagram showing the structure of the lower jig and upper jig of the stem molding die, FIG. Figure 7 (
a) and (b) are respectively a front view and a plan view showing the structure of the glass stem; FIGS. 8(a) to (C) are plan views each showing the shape of a conventional header that is preformed before the stem is formed; FIG. 9 is a diagram for explaining the conventional header molding method. 1... Flare 2... Exhaust pipe 3... Lead 6... Fillet 21... Rotary table 23... Lower jig 24... Concavity 26
...Exhaust pipe insertion hole 27...Lead insertion hole 29.
...Header forming device 30...Header pushing device

Claims (1)

[Claims] An exhaust pipe is inserted into an exhaust pipe insertion hole in a lower jig of a stem molding die, and a plurality of leads are inserted into a plurality of lead insertion holes provided around the exhaust pipe insertion hole. Along with inserting
A step of arranging a ring-shaped glass header to surround the plurality of leads, a step of heating and softening the header placed in the lower jig, and a step of rotating the lower jig and adjusting the tip part to a diameter. The header is heated and softened while rotating a header molding die having a tapered surface with a small tapered surface and a plurality of lead insertion holes corresponding to the lead insertion holes of the lower jig in synchronization with the lower jig. expanding the upper end of the header into a trumpet shape with the tapered surface; heating and softening the expanded header to roll the upper end side to the outside of the header; The lower jig is rotated while a rotary roller is pressed against the outer peripheral surface of the header whose height has been reduced to push the heated and softened header inward. A process of welding the header to the plurality of leads, and heating and softening the end of the exhaust pipe inserted into the exhaust pipe insertion hole of the lower jig and the header welded to the leads, and then heating and softening the header welded to the leads. 1. A method for manufacturing a glass stem, comprising the step of combining a jig with an upper jig of a stem molding die and forming the stem into a stem.