JPS5889753A - Manufacture of ring-shaped fluorescent lamp - Google Patents

Abstract

PURPOSE:To manufacture a fluorescent lamp having a ring form nearly equal to a true circle by installing a guide roller oppositely to a taking-up drum and permitting a softened glass bulb to be closely fitted onto the taking-up drum when the glass bulb is taken-up. CONSTITUTION:The exhaust pipe 2 of a glass bulb 1 is held onto a working head 3, the upper neck part 4 is held by a holding piece 5 and heated until softened. While, a taking-up drum 6 advances together with an installation bracket 7, when the softened glass bulb 1 reaches a taking-up station, and the lower neck part 9 of the bulb 1 is held by the chucks 8a and 8b installed on the side surfaces of right and left taking-up drums 6a and 6b. While, the glass bulb guides 10a and 10b set oppositely to the drum 6 are installed at the top edges of the arms 11a and 11b fixed on brackets 7a and 7b. Said guides 10a and 10b are arranged to interpose and hold the bulb 1 between them oppositely to the drum 6 during taking-up operation, so the bulb 1 is certainly attached onto the drum 6, and thus the bulb 1 is prevented from being elongated over the necessary size, and can be shaped in a ring form nearly equal to a true circle.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an annular fluorescent lamp, and more particularly, to a manufacturing method suitable for improving the accuracy of bending a glass tube into an annular shape.

In the conventional method of bending a glass tube into an annular shape in manufacturing annular fluorescent lamps, when winding a softened straight glass tube onto a drum, the upper part of the glass tube is bent from the first winding drum as shown by line A in Figure 1. As the distance increases, the amount of elongation becomes large, and when the first winding is completed, the excess portion protrudes from the drum diameter, which has the disadvantage that it tends to become non-circular as shown in the second barrier. Inconsistency in shape was a problem.

In addition, excessive force is applied to the exhaust pipe, causing breakage of the exhaust pipe and other causes of reduced yield.

Therefore, one object of the present invention is to provide a method for manufacturing an annular fluorescent lamp, which allows a softened glass tube to be reliably brought into close contact with a winding drum to obtain an annular fluorescent lamp that is close to a perfect circle.

In order to achieve the above object, the present invention.

A guide roller is provided opposite the winding drum to ensure that the glass tube comes into close contact with the winding drum during winding, thereby manufacturing an annular fluorescent lamp.

Embodiments of the present invention will be described below with reference to FIG. 1.3.4.

The glass tube 1 is held with the exhaust pipe 2 in working order 3.

Its upper end neck portion 4 is held by a holding piece 5.

It is heated until it becomes soft. On the other hand, the winding 9 and the winding 6 are as follows until the glass tube l reaches the winding station.
As shown in Figure 4, it opens left and right.

The glass tube 1 is moved back to a position out of the transport trajectory of the glass tube 1, and when the softened glass tube 1 reaches the 1st winding station, the 1st winding drum 6 and the mounting bracket 7 move forward together, and are divided into halves. Left and right winding drums am, ct
It was installed on the side of b. The chucks ga and gb grip the lower neck portion 9 of the glass tube 1 as the one-winding drums 6a and 6b close.

The other one faced the winding drum 6. Glass tube guide 10
a and 10b are respectively attached to the tips of the arms A11a#llb fixed to the left and right brackets 7a and 7b, and are rotatable rollers having a cross-sectional shape that matches the diameter of the glass tube 1. As shown in FIG. 3, due to the closed state of winding drums 5a and 5b together with 8b,
The left and right sides are closed.

After the lower neck portion 9 is gripped by the chucks 8a and 8b, the winding drum 6 is moved by the upward movement of the bracket 7.
The vinyl gear 13 meshed with the rack gear 12 rotates, and the intermediate gear 14a.

14b, etc., and wind up the softened glass tube 1 while rising.

On the other hand, the glass tube guides 10a and 10b are also brackets) 7
During one winding operation, the glass tube 1 is always opposed to the winding drum 6 and restrained so as to be clamped, and the glass tube 1 is securely held on the one winding drum until the end of one winding. 6 to prevent the glass tube 1 from elongating more than necessary, and to form an annular shape along the outer surface of the one-winding drum in a nearly perfect circle as shown by the imaginary line B in FIG.

According to the manufacturing method of the present invention, when the softened glass tube is bent into an annular shape, it is opposed to the winding drum.

Since a guide is provided and the glass tube is held in place during one winding operation, the glass tube can be prevented from coming loose from the winding drum, and it is possible to form a ring into a shape closer to a perfect circle. In addition, the manufacturing method of the present invention can be easily carried out by simply adding it to a winding device of conventional equipment, and since a guide is installed in the winding device itself, the distance between the winding drum and the guide can be kept constant at all times. It is easy to maintain molding accuracy.

Furthermore, the guide is as shown in the above embodiment.

The same effect can be obtained with a single cylindrical roller, even if it is not a drum-shaped roller that matches the shape of the glass tube, or with a guide that does not make one revolution as long as it does not generate a large frictional force.

[Brief explanation of the drawing]

Fig. 1 is a side view of a small winding device for carrying out the method of manufacturing an annular fluorescent lamp according to the present invention, Fig. 2 is an external view of a lamp with a defective shape produced by the conventional method, and Fig. 3 is a cross-section of the main part of Fig. 1. FIG. 4 is a diagram showing the state of the guide when the drum is opened. 1...Glass tube, 2...Exhaust pipe, 3...Work order,
4... Upper end neck portion, 5... Holding piece, 6... Winding drum, 7... Mounting bracket, ga, sb...
Chuck, 9... Lower part, 10a, 10b...
・Glass tube guide, 11a, llb...arm, 12
...Rack gear. yAlrXU 3rd mouth/3 It 2nd solid VJ4 figure

Claims (1)

[Claims] The lower end of the glass tube, which is suspended vertically with its upper end held, is gripped by a chuck provided on a winding drum, and the winding drum is rotated while being raised, and the glass tube is wound up. In the method for manufacturing an annular fluorescent lamp in which the glass tube is wound up and bent into an annular shape along the outer peripheral surface of the drum, a glass tube guide is provided opposite the outer peripheral surface of the winding drum; As the glass tube guide rises, the glass tube guide is raised while maintaining a constant distance from the outer peripheral surface of the winding drum. A method for manufacturing an annular fluorescent lamp, comprising bending the glass tube into an annular shape while forcibly aligning the glass tube with the outer surface of the winding drum.