JPH06223714A - Fluorescent lamp manufacturing device and manufacture of fluorescent lamp - Google Patents

Abstract

PURPOSE:To provide the manufacturing device of a fluorescent lamp of a drop seal method to seal a stem in a glass pipe, by reducing the useless material of the glass pipe of the fluorescent lamp. CONSTITUTION:A stem 4 is inserted into the lower end of a linear pipe type glass pipe 1 held vertically, the sealing part m of the glass pipe 1 close to the periphery of the stem 4 is heated locally by a burner 9, and the sealing part m is fused to the stem 4. To this stem sealing machine, a chuck mechanism 7 to pull down the glass pipe 1 by holding adequately the lower part of a cullet 2 lower than the sealing part m of the glass pipe 1 is attached. The chuck mechanism 7 lowers the cullet 2 while holding the nonsoftened part n at the lower part of the cullet 2 with a pair of chucks 8, so as to fuse out the cullet 2 from the sealing part m positively. By removing the cullet 2 in such a way, the length L2 of the cullet 2 to be removed after the stem 4 is sealed to the glass pipe 1 is made shorter, so as to suppress the useless material of the glass pipe 1 at the minimum value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing apparatus for enclosing a stem with an electrode in an end portion of a glass tube of a fluorescent lamp and a manufacturing method of the fluorescent lamp.

[0002]

2. Description of the Related Art Generally, ring fluorescent lamps are manufactured by a process of forming a phosphor coating on the inner surface of a straight tube glass tube, an encapsulation step of welding stems with electrodes to both ends of the straight tube glass tube, and a straight tube type. The bending process of bending the glass tube into an annular shape and the exhausting step of exhausting the impure gas in the annular glass tube to activate the electrodes and then filling the necessary gas are performed in this order.

A specific example of the enclosing process is shown in FIGS.
Shown in (c) and explained, this figure shows the process of enclosing the stem (4) at the end of the straight glass tube (1 ') by the drop seal method.

First, as shown in FIG. 5 (a), a straight tube type glass tube (1 ') mounted vertically on a turntable (not shown) and intermittently fed horizontally is mounted in the lower end portion thereof. Insert the stem (4) held at the upper end of the pin (6). The total length of the glass tube (1 ') is set longer than the final length of the fluorescent lamp, and the phosphor coating (3) is provided on the inner surface of the glass tube (1').
Is formed, and the phosphor coating (3) on the inner surface of the enclosed portion (m) at a predetermined distance from both ends of the glass tube (1 ') is deleted. The stem (4) has an electrode (5), and its flared peripheral edge approaches the enclosed portion (m) of the glass tube (1 '). The mount pin (6) is intermittently fed horizontally along with the glass tube (1 '), and the glass tube (1') and the mount pin (6) are rotated at a predetermined heating position to seal the glass tube (1 '). The part (m) is externally heated by the burner (9).

When the enclosed portion (m) of the glass tube (1 ') is sufficiently heated, the enclosed portion (m) is shrunk and the peripheral portion of the stem (4) is shown in FIG. 5 (b). Weld to.
Then, the enclosed portion (m) is melted by the dead weight of the cullet portion (2 '), which is an unnecessary portion below the enclosed portion (m) of the glass tube (1'), and the cullet is removed as shown in Fig. 5 (c). Department (2 ')
Separates from the glass tube (1 ') and falls naturally.

A glass tube (1 ') in which a stem (4) is enclosed
The lower end of the is molded as required as shown in FIGS. 6 (a) and 6 (b). First, as shown in FIG. 6A, the lower end of the glass tube (1 ') is heated by the burner (10) to be softened. Next, as shown in FIG. 6 (b), the lower end of the softened glass tube (1 ') is pressed from both sides by a mold (11) divided into two parts, and a groove (12) is formed on the outer periphery of the lower end. ) Is formed. The groove (12) is used as a glass tube supporting means when the straight tube type glass tube (1 ') is bent into an annular shape later.

A straight tube type glass tube (1 ') in the manner shown in FIGS.
When the stem encapsulation and the molding at the lower end of the glass tube (1 ') are completed, the glass tube (1') is turned upside down, and the stem encapsulation and the molding at the other end of the glass tube (1 ') are performed in the same manner as above. The glass tube (1 ') having a predetermined length with stems enclosed at both ends is sent to the next bending step while being supported vertically, and the whole is heated and bent into an annular shape.

[0008]

Problems to be Solved by the Invention FIGS. 5 (b) to 5 (c)
In the stage, the shorter the length L ₁ of the cullet portion (2 ′) of the glass tube (1 ′) and the lighter the cullet portion (2 ′),
The cullet part (2 ') is less likely to fall due to its own weight, increasing the possibility that accurate drop sealing cannot be performed. Therefore, the length L ₁ of the cullet portion (2 ′) in the glass tube (1 ′) is increased to set the weight of the cullet portion (2 ′) to a large value, and the stem (4) is attached to the enclosed portion (m). The cullet part (2 ') is designed to easily fall due to its own weight after welding. For example, the length L ₁ of the cullet portion (2 ′) is required to be about 25 to 40 mm in a normal fluorescent lamp in order to perform a normal drop seal.

However, the longer the length L ₁ of the cullet portion (2 ′) that is discarded after the stem of the glass tube (1 ′) is enclosed, the more material is wasted in the glass tube (1 ′), and The material waste of the phosphor coating (3) on the inner surface of the cullet portion (2 ') also increases. Since the cullet portion (2 ') exists at both ends of the glass tube (1'), the material waste is doubled, which makes it difficult to reduce the material cost for manufacturing the fluorescent lamp.

It is an object of the present invention to manufacture a fluorescent lamp in which the cullet portion which is eliminated after the stem is sealed by the drop sealing method of the end of the glass tube is short and the cullet portion is surely dropped to carry out the stem sealing. To provide a device.

[0011]

In order to achieve the above object, the device of the present invention is such that a stem with an electrode is inserted into the lower end of a vertically supported straight glass tube, and the stem is substantially equivalent to the peripheral portion of the stem. The glass tube is applied to the stem sealing machine of the drop seal type which heats the glass tube portion to weld the peripheral portion of the stem and the glass tube together, and melts and eliminates the lower glass tube (cullet portion) from the welded portion. After heating, the chucking mechanism is attached to hold and pull down the non-softened part of the cullet part.

Further, in the method of the present invention, the stem with an electrode is arranged inside the lower end of the vertically supported straight glass tube so that the peripheral portion of the stem is located above the lower end of the glass tube. The present invention is characterized by including a step, a step of heating a glass tube portion substantially corresponding to the peripheral portion of the stem to weld them together, and a step of holding a non-softened portion below the welded portion by a chuck mechanism and pulling it down.

[0013]

[Operation] When the enclosed portion of the lower end of the vertically supported straight glass tube is heated and welded to the stem, the non-softened portion of the cullet portion below the enclosed portion of the glass tube is held by the chuck mechanism. If the cullet is positively pulled downwards, the cullet part will melt and fall off from the glass tube mainly due to the external force of the chuck mechanism, and as a result, the cullet parts at both ends of the glass tube will be short and lightweight. Useful for enclosing the stem.

[0014]

Embodiments of the present invention will be described below with reference to FIGS. Note that the same or corresponding portions are denoted by the same reference symbols throughout the drawings including FIG. 5, and description thereof will be omitted.

The straight tube type glass tube (1) shown in FIG.
A phosphor coating (3) is formed on the inner surface, and the phosphor coating (3) on the inner surface of the enclosed portion (m) at a certain distance from both ends is peeled off, and the peripheral portion of the stem (4) is enclosed in the enclosed portion (m). Is welded. The length L ₂ of the cullet portion (2) beyond the enclosed portion (m) of the glass tube (1) is the length L of the cullet portion (2 ′) of the glass tube (1 ′) of FIG. Set shorter than ₁ .

In the present invention, a stem enclosing machine which encloses the stem (4) in a drop-sealing type in a straight tube type glass tube (1) shorter than before is moved forward and backward as shown by an arrow in FIG. 1 (b). Chuck mechanism (7) with chuck (8)
Attaching a vertical glass tube (1) with a chuck mechanism (7)
The cullet (2) at the lower end of the is forcibly melted and dropped. The chuck (8) of the chuck mechanism (7) is a lower part of the cullet part (2) of the vertical glass tube (1) and holds a non-softened part (n) that does not shrink by heating the enclosed part (m). Pull down. The chuck mechanism (7) is arranged separately from the stem enclosing machine, and is independently driven in synchronization with the drive of the stem enclosing machine as follows.

First, as shown in FIG. 1 (a), a straight tube type glass tube (1) is vertically supported and a stem held by a mount pin (6) up to an enclosed portion (m) at its lower end. (Four)
Insert. The glass tube (1) and the mount pin (6) are intermittently fed in the horizontal direction, and the enclosed portion (m) is externally burned by a burner (9) while rotating the glass tube (1) and the mount pin (6) at the heating position. Heat to soften. Next, FIG.
As shown in (b), the sealed part (m) of the glass tube (1) is sufficiently heated and shrunk and welded to the stem (4), and the cullet where the chuck mechanism (7) is placed is removed. When loaded into the position, the pair of chucks (8) of the chuck mechanism (7) are closed and lowered as shown in FIGS. 2 (a) and 2 (b).

At the lower end of the glass tube (1), the enclosed part (m) is heated and softened, and this heating causes the upper part of the cullet part (2) to shrink with the enclosed part (m). The lower part of () is a non-softened part (n) that does not soften sufficiently. A pair of open chucks (8) stands by on both sides of the non-softened portion (n). When the glass tube (1) stops rotating and is carried into the cullet exclusion position of the chuck mechanism (7), the pair of chucks (8) close and hold the non-softened part (n) below the cullet part (2). Then, it descends to the lower limit position.

Then, as shown in FIG. 2 (a), the cullet portion (2) held by the chuck (8) is replaced by the glass tube (1).
And the enclosed portion (m) to which the stem (4) is welded is surely melted and the cullet portion (2) separates from the glass tube (1) and descends. The pair of chucks (8) opens when lowered to the lower limit position, rises to the original upper limit position, and waits until the next glass tube (1) is loaded.

When the chuck (8) is opened at the lower limit position of FIG. 2 (a), the cullet part (2) separated from the glass tube (1) falls by its own weight, as shown in FIG. 2 (b), for example. It drops to the chute (13) installed at the fixed position below. The cullet part (2) that has fallen onto the chute (13) is removed from the stem (4) by the mount pin (6) and descends below the chute (13). Excluded from the outside.

The glass tube (1) from which the cullet has been removed at the cullet removing position is sent to the subsequent position while being supported vertically, and the lower end portion with the stem enclosed is heated in the same manner as in FIG. Molded. Then, the glass tube (1) is turned upside down, and the stem is sealed at the other end in the same manner as described above.

Since the cullet part (2) of the glass tube (1) in which the stem is sealed in the device of the present invention is positively melted and removed from the glass tube (1) by the chuck mechanism (7), the cullet part (2) is removed. For 2), a short and lightweight one is sufficient. In other words, when the enclosed portion (m) of the glass tube (1) is heated, the non-softened portion (of a length long enough to hold the chuck (8) of the chuck mechanism (7) in the cullet portion (2) satisfactorily ( n)
, The maximum value of the length L ₂ of the cullet portion (2) is determined. The length L ₂ of this cullet portion (2) is as shown in FIG.
Required minimum length L of the cullet part (2) of the glass tube (1)
As a result of experiments, it is known that about 50 to 70% of ₁ is sufficient. These two glass tubes with different lengths (1) (1 ')
A comparison of the lengths of is shown in FIG. Difference in length of the cullet parts (2) (2 ') of both glass tubes (1) (1') (L ₁
-L ₂ ) is twice the difference in the total length of both glass tubes (1) (1 '), and the difference in the total length reduces the material waste of the glass tube (1) used in the device of the present invention. Become.

[0023]

According to the present invention, when the stem is welded and sealed to the enclosed portion of the lower end portion of the vertically supported straight tube type glass tube, the cullet portion below the enclosed portion of the glass tube is exposed to the outside. Since the cullet part is positively pulled down by the chuck mechanism, the cullet part surely melts from the glass tube and falls off.
The length of the cullet part that is eliminated after the stem is sealed at both ends of the glass tube can be minimized, and the material waste such as the glass tube and the phosphor coating on the inner surface of the glass tube can be significantly reduced, which reduces the manufacturing cost of the fluorescent lamp. It becomes possible easily.

[Brief description of drawings]

FIG. 1 is a side view including a partial cross-section of a glass tube in a stem encapsulation step of manufacturing a fluorescent lamp, (a) is a side view when heating a glass tube, and (b) is a side view before removing a cullet including a chuck mechanism in the present invention. Side view

2 is a side view including a partial cross section of the glass tube when the cullet is removed from the glass tube of FIG. 1, (a) is a side view when the cullet is pulled down, and (b) is a side view when the cullet is dropped.

FIG. 3 is a sectional view taken along the line AA of FIG.

FIG. 4 is a side view including partial cross sections of two glass tubes having different lengths.

FIG. 5 is a side view including a partial cross section of a glass tube in a stem encapsulation process using a conventional apparatus for manufacturing a fluorescent lamp,
(A) is a side view when the glass tube is heated, (b) is a side view when the glass tube is sealed, and (c) is a side view when the cullet is dropped.

6 is a side view including a partial cross section of the glass tube in the glass tube end molding step of FIG. 5, (a) is a side view when the glass tube is heated, and (b) is a side surface when the glass tube is molded. Figure

[Explanation of symbols]

 1 Glass tube 2 Cullet part m Enclosed part 4 Stem 5 Electrode 7 Chuck mechanism

Claims (2)

[Claims] 1. A stem with electrode is inserted into the lower end of a vertically supported straight glass tube, and the glass tube portion substantially corresponding to the peripheral edge of the stem is heated to heat the peripheral edge of the stem and the glass tube. After the glass tube is heated, the part of the cullet part in the non-softened state is held by a drop-seal type stem enclosing machine that melts and removes the glass tube (cullet part) below the welded part. A fluorescent lamp manufacturing apparatus characterized in that a chuck mechanism for pulling it down is additionally provided. 2. A step of disposing an electrode-equipped stem inside the lower end of a vertically supported straight glass tube so that the peripheral edge of the stem is located above the lower end of the glass tube. A method of manufacturing a fluorescent lamp, comprising: a step of heating a glass tube portion substantially corresponding to a peripheral edge portion to weld them together; and a step of holding a non-softened portion below the welded portion by a chuck mechanism and pulling it down.