JP2004200007A - Manufacturing device for circular fluorescent lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a straight glass tube 31a into a precise circular shape without deflection, which tube is heated and softened, in the manufacturing device of a circular fluorescent lamp. <P>SOLUTION: The deflection of the straight glass tube 31a which is transferred between a pair of heating furnaces 1 is detected at the final position by CCD cameras 20a, 20b, 21a, 21b which are provided for detecting the deflection of the straight tube glass 31, and that deflection is corrected by moving each of tube receiving pins 2 by the XY drive mechanism 10a and 10b. And the straight tube glass 31a having no deflection is supplied to a bending machine. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for manufacturing an annular fluorescent lamp, and more particularly to an apparatus for manufacturing an annular fluorescent lamp in a thermal softening process of a straight tube glass before a glass tube bending process.
[0002]
[Prior art]
Usually, a ring-shaped fluorescent lamp is bent and formed into a ring shape by using a bent roller having a split structure after heating and softening a straight tube glass tube. However, there is a problem that when a straight glass tube is bent into a ring shape by a curved roller and the bent roller is released, the formed circular glass tube is deformed by twisting and does not become a perfect circular ring shape. It was.
[0003]
Various methods and manufacturing apparatuses for solving the problem of deformation have been proposed. FIGS. 5A and 5B are a front view and a plan view for explaining an apparatus for manufacturing an annular fluorescent lamp in a conventional example, and FIGS. 6A to 6C are apparatuses for manufacturing the annular fluorescent lamp of FIG. It is a figure for demonstrating operation | movement of.
[0004]
As shown in FIG. 5, the annular fluorescent lamp manufacturing apparatus includes a turntable 32 on which a heat-softened straight tube glass tube is mounted, and an upper end of the straight tube glass tube gripped by a chuck 38. A bending machine having a bending roller for holding the lower end of the tubular glass tube and forming the straight tubular glass tube in an annular shape, and a correction plate 35 for correcting deformation caused by twisting of the annular shaped glass tube 31b. And a corrector 34 having a drive mechanism 36 for moving the correction plate 35 in the direction of the arrow.
[0005]
Then, the pair of correction plates 35 are moved to the drive mechanism 36, and the annular glass tube 31b is inserted into the pair of correction plates 35 as shown in FIG. 6 (a). After that, as shown in FIG. 6B, the deformation of the annular glass tube 31b was corrected by sandwiching it with the correction plate 35 by the pressing force of the cylinder 37 (see Patent Document 1).
[0006]
[Patent Document 1]
Japanese Utility Model Publication No. 6-64351 (page 9-10, FIGS. 3, 4 and 5)
[0007]
[Problems to be solved by the invention]
In the conventional annular fluorescent lamp manufacturing apparatus described above, when the straight tube glass tube is heated and softened, it is assumed that the straight tube glass tube is not bent, and the deformation after bending is corrected. Yes.
[0008]
However, in practice, the straightened glass tube that has been softened by heating does not become straight but has a bend of about several millimeters. Although deformation caused by twisting by the bending machine due to this degree of bending can be corrected by the above-described annular fluorescent lamp manufacturing apparatus, it is difficult to correct the deformation with a straight glass tube having more bending.
[0009]
In particular, a slim straight tube glass tube has a smaller outer diameter (8 mm) than a normal annular fluorescent lamp (outer diameter 30 mm), and a heat-softened straight tube glass tube is bent several tens of millimeters. Therefore, there is a problem that it cannot be normally formed into an annular shape by a bending machine and is difficult to correct.
[0010]
Accordingly, an object of the present invention is to provide an apparatus for manufacturing an annular fluorescent lamp capable of forming a straight tube glass tube that is heated and softened into an accurate annular shape without bending.
[0011]
[Means for Solving the Problems]
A feature of the present invention is that a chain drive mechanism that intermittently conveys a plurality of straight glass tubes that are suspended in one direction while holding the upper end without restraining the lower end, and the plurality of straight tubes that are conveyed A pair of heating furnaces arranged on both sides of the shaped glass tube for heating the straight tube shaped glass tube, and a lower end of the straight tube shaped glass tube conveyed in a station near the outlet of the heating furnace. An annular fluorescent lamp manufacturing apparatus including a tube receiving pin to be inserted and extracting the tube receiving pin from a lower end of the straight glass tube heated and softened by the heating furnace and sending it to a station in a glass bending process.
[0012]
Moreover, it is desirable that the plurality of straight tube-shaped glass tubes be provided with suspension fittings that are suspended in two rows. And it is desirable to provide the detector which detects the bending of the said straight tube | pipe type glass tube hold | maintained by the said tube receiving pin, and the bending correction means which correct | amends the bending detected by this detector. Further preferably, the detector uses a CCD camera.
[0013]
The bend correcting means divides the bending component of the straight glass tube into a direction parallel to the direction in which the heating furnaces are arranged (X direction) and a direction perpendicular to the parallel direction (Y direction), and the divided components are divided. It is desirable to provide an XY moving mechanism for moving the tube receiving pin that corrects the component. On the other hand, it is desirable that the XY moving mechanism includes a shielding plate that is installed in a trench formed by being dug down from a floor surface and closes the opening of the trench.
[0014]
Preferably, a shielding plate for closing the opening of the trench is provided, preferably measuring means for measuring the outer diameter of the heated straight tube type glass tube, and finely moving the tube receiving pin up and down from the measuring means. And a height adjusting means. Further, the detector for measuring the outer diameter of the heated straight glass tube is measured, the measured data is collected, and the tube receiving pins are moved up and down according to the data. It is desirable to provide an up-and-down fine adjustment mechanism for fine movement.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be described with reference to the drawings.
[0016]
FIG. 1 is a perspective view showing a configuration of an apparatus for manufacturing an annular fluorescent lamp according to an embodiment of the present invention. As shown in FIG. 1, this annular fluorescent lamp manufacturing apparatus is a chain that intermittently conveys a plurality of straight tube-shaped glass tubes 31a that are held and suspended in one direction without being constrained at the lower ends. The drive mechanism 4, a pair of heating furnaces 1 that are arranged on both sides of a plurality of straight glass pipes 31 a to be conveyed and heat the straight glass pipes 31 a, and a final that is near the furnace outlet 6 of the heating furnace 1 The tube receiving pin 2 is provided at the lower end of the straight tube-shaped glass tube 31a conveyed at the position station 4a.
[0017]
The straight glass tubes 31a passing between the heating furnaces 1 having a plurality of gas burners on the inner wall surface are arranged in two rows in consideration of the ability to uniformly heat the straight glass tubes 31a and productivity. It is desirable. The pair of straight glass tubes 31 a are held by the suspension fitting 3 that is fixed to the link of the chain drive mechanism 4. Further, the straight glass tube 31a runs in the heating furnace 1 at a constant speed without being restrained at the lower end, is gradually heated, and is sent to the final position station 4a without being stressed.
[0018]
As the straight glass tube 31a approaches the final position station 4a, the rail height of the track rail 8 gradually increases, the plate 9 rises, and the tube receiving pin 2 rises accordingly. Then, a taper-like pin at the tip of the tube receiving pin 2 is inserted into the recess at the lower end of the straight glass tube 31b. Since this insertion operation is performed extremely statically, no stress is applied to the straight glass 31b.
[0019]
And it stops temporarily at this final position station 4a, and the straight tube-shaped glass tube 31a reaches | attains the softening temperature of glass. Next, the plate 9 moves backward, and the tube receiving pin 2 is pulled out from the straight glass tube 31a without applying stress to the lower end of the straight glass tube 31a. The straight glass tube 31 a having a free lower end is sent to the chain drive mechanism 4 and positioned at the bending position station 5.
[0020]
The mount pin 7 is inserted into the lower end of the straight tube-shaped glass 31a sent to the bending position station 5, and the position is fixed. The straight glass tube 31a is held by the turntable chuck of the bending machine directly above, and is wound up by the bending roller so that the straight glass tube 31a is formed into an annular shape. As described above, since the straight tube glass 31a is transported without being stressed while being heated, the straight tube glass tube 31a is in a straight state even when thermally softened. Can be loaded by a composer that performs
[0021]
FIG. 2 is a perspective view showing the configuration of an apparatus for manufacturing an annular fluorescent lamp according to another embodiment of the present invention. As shown in FIG. 2, the annular fluorescent lamp manufacturing apparatus includes CCD cameras 20a, 20b, which measure the bending of a straight glass tube 31 suspended from a chain drive mechanism 4 and having tube receiving pins inserted therein. 21a, 21b, the control device 11 for inputting the bending data of the straight glass tube 31a, and the tube receiving pins 2 are independently set to X and Y according to the bending data input by the control device 11. XY drive mechanisms 10a and 10b that move in the direction and correct the bending of the straight glass tube 31a are provided.
The XY drive mechanism 10a includes ball screws 15 and 16 and a guide bar for moving the plate 9 on which the tube receiving pin 2 is mounted and the base plate 19 on which the rail 8 is mounted in the X and Y directions. -17a and 17b and spline shafts 13 and 14, and a motor 12 which is a pulse motor for rotating the ball screws 15 and 16 of the feed mechanism via a pair of bevel gears. Of course, ball nuts (not shown) rotatably mounted on the spline shafts 13 and 14 mesh with the respective ball screws 15 and 16 and interfere with the movement of the base plate 19 in the X and Y directions. It has a structure that does not.
[0022]
Here, since the XY drive mechanism 10b has the same structure as the XY drive mechanism 10a, description thereof is omitted. The XY drive mechanisms 10a and 10b are preferably installed in a trench dug down from the floor surface in order to avoid heat radiation from the heating furnace 1, and a heat shielding plate that covers the trench is preferably provided. In particular, it is desirable that the motor 12 that is susceptible to heat is vertically attached to the mounting plate so as not to receive heat radiation. This ring fluorescent lamp manufacturing apparatus is suitable for a slim straight glass tube which is easily bent.
[0023]
FIGS. 3A and 3B are diagrams for explaining the correction of the bending of the straight glass tube. CCD camera 20a, 20b shown in FIG. 2 images each center part of the straight glass tube 31a. The CCD cameras 21a and 21b take images of the lower ends of the straight glass tubes 31a. These CCD cameras 20 a, 20 b, 21 a, 21 b are arranged at positions away from the furnace outlet 6 so as to avoid radiant heat from the furnace outlet 6. Further, the visual axis of the CCD camera has an angle at which an image can be taken from the gap between the furnace outlets 6 and the image pickup surface is directed at, for example, 45 degrees with respect to the direction in which the furnaces are arranged.
[0024]
For example, as shown in FIG. 3, imaging by a CCD camera 20a and a CCD camera 21a arranged with the imaging surface inclined by 45 degrees with respect to the central axis in which the heating furnaces 1 are arranged is shown. The image shown in FIG. 3B is a straight glass tube 31a tilted from the reference line. On the other hand, the imaging shown in FIG. 3A shows a straight glass tube 31a bent by δ from the reference line.
[0025]
This bend δ is a bend when it is tilted 45 degrees. Here, it is necessary to divide this bending amount δ into components in the X direction (a direction parallel to the furnace arrangement direction) and the Y direction (a direction perpendicular to the furnace arrangement direction). That is, the bending components in the X direction and the Y direction are δ * COS 45 degrees and δ * SIN 45 degrees.
[0026]
The calculation of the bending component of δ in the X direction and the bending component of δ in the Y direction is automatically calculated by the calculation unit of the control device 11 in FIG. Then, the calculated data value is sent to the NC device of the control device 11, and signals of the number of pulses are transferred to the motors 12 in the X direction and the Y direction according to the data values. The image is picked up again by the CCD cameras 20a and 21a, and it is determined whether or not the bending is corrected. If the bend is below the specified value, complete the measurement. If there is still a bend, the control unit 11 is fed back to correct the bend.
[0027]
FIG. 4 is a view for explaining a modification of the apparatus for manufacturing a ring-shaped fluorescent lamp according to another embodiment of the present invention. As shown in FIG. 4, the annular fluorescent lamp manufacturing apparatus includes upper and lower XY drive mechanisms 10a and 10b for correcting the bending of the straight glass tube 31a in the annular fluorescent lamp manufacturing apparatus of the above-described embodiment. The fine movement mechanism 22 is provided. In particular, a slim straight-tube glass tube may not only bend, but the outer diameter of the tube may become thinner or thicker.
[0028]
Therefore, in order to correct the outer diameter of the straight glass tube, the tube receiving pin 2 is slightly moved up and down at the final position 4a in FIG. The vertical fine movement mechanism includes a mounting table 25 on which the XY drive mechanism 10a in the trench 29 is placed, a feed screw 27 and a nut 28 that finely move the mounting table 25 up and down, a guide bush 26 that accurately guides the mounting table 25 up and down, and A guide post 23 and a motor 24 for rotating the nut 28 by a pulse signal transferred from the control device 11 of FIG. 2 are provided.
[0029]
In this tube outer diameter correcting operation, first, the outer diameter of the corresponding straight tube glass tube 31a is measured by each of the CCD camera 20a and the CCD camera 20b that images the central portion of the straight tube glass tube 31a. If the outer diameter is smaller than the prescribed outer diameter, the difference data between the prescribed outer diameter and the measured outer diameter is transferred to the control device 11. Then, the calculation unit of the control device 11 transfers the number of pulses to the motor 24 via the NC device according to the difference data, and the mounting table 25 is raised as the motor 24 rotates.
[0030]
Again, the outer diameter of the straight glass tube 31b is measured by the CCD camera 20a and the CCD camera 20b and compared with a specified value to determine whether or not the correction has been made. The present invention is not limited to the XY drive mechanism and the vertical fine movement mechanism by the NC device described above, and for example, analog control using a DC servo motor may be used.
[0031]
【The invention's effect】
As described above, the present invention allows the upper end of the straight tube glass tube to be hung and statically conveyed in the furnace without restraining the lower end before being formed into an annular glass tube, and gradually heated and softened. Therefore, there is an effect that the straight glass tube that is heated and softened can be formed into an accurate annular shape without bending, and the yield can be improved.
[0032]
Further, by providing means for detecting in advance the bending of the straight tube glass tube and means for correcting the bending as required, a straight tube glass tube with less bending is passed to the glass tube bending step. And the effect can be further exhibited.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a configuration of an apparatus for manufacturing an annular fluorescent lamp according to an embodiment of the present invention.
FIG. 2 is a perspective view showing a configuration of an apparatus for manufacturing an annular fluorescent lamp according to another embodiment of the present invention.
FIG. 3 is a view for explaining correction of bending of a straight glass tube.
FIG. 4 is a view for explaining a modification of the manufacturing apparatus for the annular fluorescent lamp according to another embodiment of the present invention.
FIGS. 5A and 5B are a front view and a plan view for explaining an apparatus for manufacturing an annular fluorescent lamp in a conventional example. FIGS.
6 is a diagram for explaining the operation of the manufacturing apparatus for the annular fluorescent lamp of FIG. 5;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Heating furnace 2 Tube receiving pin 3 Suspension metal fitting 4 Chain drive mechanism 5 Bending position station 6 Furnace outlet 7 Mount pin 8 Rail 9 Plate 10a, 10b XY drive mechanism 11 Controller 12 Motor 13 , 14 Spline shaft 15, 16 Ball screw 20a, 20b, 21a, 21b CCD camera 22 Vertical movement mechanism 27 Feed screw 28 Nut

Claims (7)

A chain drive mechanism that intermittently conveys a plurality of straight tube glass tubes that are suspended in one direction while holding the upper end without restraining the lower ends, and on both sides of the plurality of straight tube glass tubes to be conveyed A pair of heating furnaces arranged to heat the straight tube glass tube, and a tube receiving pin inserted into a lower end of the straight tube glass tube conveyed at a station near the outlet of the heating furnace; And the tube receiving pin is pulled out from the lower end of the straight tube-shaped glass tube heated and softened by the heating furnace, and sent to a station in the glass bending step. The apparatus for manufacturing an annular fluorescent lamp according to claim 1, wherein the plurality of straight tube-shaped glass tubes are provided with suspension fittings suspended in two rows. 2. The detector according to claim 1, further comprising: a detector for detecting a bend of the straight glass tube held by the tube receiving pin; and a bend correcting means for correcting the bend detected by the detector. 2. An apparatus for producing an annular fluorescent lamp according to item 2. 4. The apparatus for manufacturing an annular fluorescent lamp according to claim 3, wherein the detector is a CCD camera. The bend correcting means divides the bending component of the straight glass tube into a direction parallel to the direction in which the heating furnaces are arranged (X direction) and a direction perpendicular to the parallel direction (Y direction), and the divided components are divided. 5. An apparatus for manufacturing an annular fluorescent lamp according to claim 3, further comprising an XY moving mechanism for moving the tube receiving pin that corrects the component. 6. The apparatus for manufacturing an annular fluorescent lamp according to claim 5, wherein the XY moving mechanism is provided in a trench formed by being dug down from a floor surface and includes a shielding plate that closes the opening of the trench. Measured by the detector that measures the outer diameter of the heated straight glass tube, collects the measured data, and finely moves the tube receiving pin up and down according to the data. An apparatus for manufacturing an annular fluorescent lamp according to claim 3, further comprising a vertical fine adjustment mechanism.

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