JP2002003232A - Device and method for cutting glass tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for cutting a glass tube, wherein a positioning place in the axial direction of a glass tube is adjustable corresponding to the outside diameter size of the glass tube and the rate of acceptable products can be improved. SOLUTION: An outside diameter of the glass tube 1 is determined by means of an outside diameter measuring means 6, a difference in an outside diameter between the glass tube 1 and a standard outside diameter is calculated. In accordance with a movement that is computed by multiplying the above difference and a coefficient, a height of a guide plate 3b in the vicinity of the cutter 5 is automatically raised/lowered, so that a cutting position where the glass tube 1 is cut by the cutter 5 is adjusted to a position in a tubular axis direction corresponding to the outside diameter of the glass tube 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass tube,
The present invention relates to a method and an apparatus for cutting a glass tube for a fluorescent lamp.

[0002]

2. Description of the Related Art Generally, a glass tube for a fluorescent lamp is manufactured by roughly cutting a glass tube continuously manufactured from a glass tube manufacturing process into a predetermined length and heating both ends of the glass tube with a burner to soften the softened portion. The drawing portion is formed by drawing with a drawing roller.

[0003] The glass tube having the narrowed portions formed at both ends is sent to a cutting step targeted by the present invention. As shown in FIGS. 4 (A) and 4 (B), a conventional cutting device has
a conveying means 2 for supporting a glass tube 1 having a and 1a movably in an axial direction, and conveying the glass tube 1 in a direction perpendicular to the tube axis while rotating the glass tube 1 around the tube axis;
A fixed guide plate 3 for positioning the position of the glass tube 1 in the axial direction by contacting the inclined surface 1b on the center side of the narrowed portion 1a of the narrowed portion 1a of the glass tube 1, A cut burner 4 for heating the glass plate 1 and a cutter 5 for cutting the heated squeezed portion 1a from a contact position of the guide plate 3 at a predetermined position in the tube axis direction of the glass tube 1;
(For example, see Japanese Patent Application Laid-Open No. 7-267667).

The aperture portion 1a of the glass tube 1 forms a portion (referred to as a color portion) for sealing a base for mounting a terminal of a fluorescent lamp. For this reason, the throttle section 1a
Is cut by the cutter 5 in the vicinity of the center portion of the base. At this time, the following is required in order to keep the sealing quality of the base constant. That is, when the base is mounted, as shown in FIG. 2A, the diameter of the glass tube at the position where the mounting end of the base comes into contact with the inclined surface 1b of the narrowed portion 1a of the glass tube 1 is defined as the baseline diameter D1. The length in the axial direction from the position of the baseline diameter D1 to the end face of the glass tube 1 is referred to as a collar length L, and the baseline diameter D1 and the collar length L are set within a predetermined tolerance range. Has been requested.

[0005]

The outer diameter D2 of the squeezed portion 1a is formed within a predetermined tolerance range by the squeezing roller in the previous process, but the outer diameter D3 of the glass tube 1 has a slight variation. is there. Therefore, as shown in FIG. 4 (C), depending on the outer diameter D3 of the glass tube 1, the aperture portion 1a
The angle of the inclined surface becomes different. In FIG. 4C, OO indicates the center line of the large-diameter glass tube 11 by O1-O.
Reference numeral 1 denotes a center line of the small-diameter glass tube 12, and a solid line shows a state in which the small-diameter glass tube 12 is supported by the transporting means 2, positioned by the guide plate 3, and cut by the cutter 5. The dashed line indicates a state in which the large-diameter glass tube 11 is supported by the transport means 2. When the small-diameter glass tube 12 and the large-diameter glass tube 11 are compared, as is clear from FIG. 4C, in the case of the large-diameter glass tube 11, when the glass tube 11 is brought into contact with the guide plate 3 and positioned, It moves only X to the left of the small diameter glass tube 12 in FIG. Then, the collar length of the large-diameter glass tube 11 is cut shorter by X than the collar length L of the small-diameter glass tube 12. Conversely, when the large-diameter glass tube 11 is used as a reference, it can be said that the small-diameter glass tube 12 is cut longer by X.

[0006] With such a cutting device, the guide plate 3 is moved to the inclined surface 1 on the center side of the narrowed portion 1 a of the glass tube 1.
b, the position of the glass tube 1 in the tube axis direction is determined, and the cutter 5 is cut from the contact portion of the guide plate 3 at a predetermined length in the tube axis direction of the glass tube 1 by contacting the cutter 5. Then, the color length L varies depending on the size of the outer diameter D3 of the glass tube 1. Therefore, there is a problem that a defective product in which the color length L is out of the predetermined tolerance range occurs.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and to provide a method and an apparatus for cutting a glass tube which can adjust the cutting position of the glass tube according to the outer diameter of the glass tube and improve the yield rate. It is to provide.

[0008]

In order to achieve the above object, a method for cutting a glass tube according to the present invention is capable of moving a glass tube having a narrowed portion having a base line diameter on an inclined surface in a tube axis direction. The glass tube is conveyed in the direction perpendicular to the tube axis while rotating while supported by the glass tube, the glass tube is moved in the tube axis direction, the inclined surface of the narrowing portion is brought into contact with the guide plate, and the position of the glass tube in the tube axis direction is determined. In a method of cutting a glass tube, in which a positioned narrowed portion of a glass tube is heated by a cut burner and a cutter is brought into contact with the heated narrowed portion, an outer diameter of the glass tube is measured, The distance between the position of the base line diameter of the inclined surface of the glass tube and the cutting position of the cutter of the glass tube is substantially constant. According to this configuration,
According to the size of the outer diameter of the glass tube, it can be cut so that the collar length falls within a predetermined tolerance range.

Further, the method for cutting a glass tube according to the present invention measures the outer diameter of the glass tube and makes the distance between the position of the base line diameter of the inclined surface and the cutting position of the cutter of the glass tube substantially constant. Further, the guide plate is displaced by an adjustment amount obtained by comparing a measured value of the outer diameter with a reference outer diameter. According to this configuration, while keeping the cutter fixed at a fixed position, the guide plate near the cutter is displaced by an adjustment amount corresponding to the magnitude of the outer diameter of the glass tube so that the collar length falls within a predetermined tolerance range. The glass tube can be easily cut.

Further, the glass tube cutting apparatus of the present invention supports a glass tube having a narrowed portion having a base line diameter formed on an inclined surface so as to be movable in the tube axis direction and to rotate the glass tube at right angles to the tube axis. Transport means for transporting the glass tube in the direction, a guide plate for positioning the position of the glass tube in the axial direction by abutting the inclined surface of the narrowed portion of the glass tube transported by the transport means and moved in the axial direction of the glass tube, A cut burner for heating the narrowed portion of the glass tube, and a cutting device for the glass tube including a cutter for cutting in contact with the heated narrowed portion, an outer diameter measuring means for measuring the outer diameter of the glass tube in advance; The amount of adjustment determined by comparing the measured value of the outer diameter measuring means with the reference outer diameter such that the distance between the position of the baseline diameter of the inclined surface and the cutting position of the cutter of the glass tube is substantially constant. Displacement Characterized in that by and a that the guide plate. According to this configuration, the guide plate in the vicinity including the installation position of the cutter can be displaced by an adjustment amount corresponding to the size of the outer diameter of the glass tube while the cutter is fixed at a fixed position. In addition, the glass tube can be cut so that the collar length of the glass tube falls within a predetermined tolerance range.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B are a schematic side view and a plan view of a glass tube cutting apparatus according to the present invention, FIG. 1C is an explanatory view of a cutting method of the present invention, and FIG. Explanatory drawings of main dimensions of the glass tube, (B) and (C) are enlarged side views and cross-sectional plan views of the conveying means, and FIG. 3 is a flowchart showing the operation of the cutting method of the present invention.

In FIG. 1, 1 is a glass tube, 2 is a conveying means, 3a is a fixed guide plate, 3b is a movable guide plate, 4 is a cut burner, 5 is a cutter, and 6 is an outer diameter measuring means. .

The glass tube 1 has squeezed portions 1a, 1a at both ends, and is conveyed one by one in a direction orthogonal to the tube axis by the conveying means 2.

The conveying means 2 comprises a pair of roller chains 2
a and 2a are arranged in parallel at a predetermined interval. The roller chains 2a and 2a are arranged in two rows by displacing rollers 2a1 and 2a2 having the same diameter in a staggered manner so as to partially overlap each other.
The glass tube 1 is placed and transported in the valley portion of the overlapping portion of a1, 2a2. As shown in FIG. 2B, the two rows of rollers 2a1 and 2a2 are connected and moved in the transport direction by a chain link 2b, and
As shown in FIG. 2C, the rollers 2a1 and 2a2 are rotationally driven in the same direction and at the same speed by another chain 2c disposed along the movement path of the rollers 2a1 and 2a2. This gives 2
Glass tube 1 placed between two rollers 2a1, 2a2
Is conveyed while rotating, is heated over the entire circumference of the glass tube 1 when passing through the position of the cut burner 4, and thereafter, when passing through the position of the cutter 5, the cutter 5 is attached to the glass tube 1. The crack is propagated and cut along the entire circumference due to the thermal shock upon contact.

The fixed guide plate 3a is installed upstream of the installation position of the outer diameter measuring means 6 by a predetermined distance from the installation position of the cutter 5, and is conveyed by the conveyance means 2 up to the cutter 5 in the pipe axial direction. Of the glass tube 1 urged toward the cutter 5 side, the inclined surface 1 at the central shoulder of the narrowed portion 1a at one end.
b is for abutting to position the glass tube 1 in the tube axis direction at a predetermined position.

The movable guide plate 3b includes a cutter 5
This is for accurately positioning the cutting position of the glass tube 1 to be cut by the method described above, and is installed in the vicinity including the installation position of the cutter 5, and a diameter difference from a reference outer diameter is obtained from a measured value of the outer diameter measuring means 6. The height can be automatically adjusted using the amount calculated by adding the coefficient to the diameter difference as the movement amount.

The cut burner 4 is for heating in advance the position of the glass tube 1 to be cut which is conveyed by the conveying means 2 and has a line burner or slit burner structure. It is configured to blow out in a shape.

The cutter 5 is used to cut a predetermined position of the narrowed portion 1a of the glass tube 1 conveyed by the conveying means 2, that is, a portion heated by the cut burner 4 by a heat shock. It has a disk shape, and its outer peripheral edge has a sharp shape so that the contact surface with the glass tube 1 is in linear contact. Here, the cutter 5 is urged upward so as to elastically contact the glass tube 1.

The cut burner 4 and the cutter 5 are
In the present embodiment, it is fixedly installed with respect to the transport means 2.

The outer diameter measuring means 6 is for measuring the outer diameter of the glass tube 1 conveyed by the conveying means 2 and includes, for example,
Laser systems and others are used. In the present embodiment, a laser system is employed. In this case, a laser light-receiving device is installed to face the upper and lower portions of the conveyance path of the glass tube 1 so as to oppose the laser beam when the glass tube 1 passes. The form is obtained by converting the outer diameter of the glass tube 1 from the time. The outer diameter measurement value obtained by the outer diameter measuring means 6 is transmitted to a machine controller as a BCD signal (binary signal) as shown in the flowchart of FIG. Is compared to
The diameter difference is obtained, a pulse signal is transmitted as a movement amount Y by adding an amount calculated by multiplying a predetermined coefficient to the diameter difference, a servo motor is driven through a servo driver, and the aforementioned The movable guide plate 3b is moved up and down. In addition, the outer diameter measuring means 6
The outer diameter measurement value of the glass tube 1 existing between the installation position of the cutter 5 and the installation position of the cutter 5 is stored, and the operation is performed according to the timing at which the corresponding glass tube 1 moves to the position of the cutter 5. Is controlled as follows.

The configuration of the embodiment of the present invention is as described above.
Next, the operation will be described. At the both ends in the pre-process, the squeezed portions 1a, 1
The glass tube 1 on which the a is formed is placed on the transporting means 2 and transported while being rotated, and when passing through the position of the outer diameter measuring means 6, its outer diameter is measured. The measured value of the outer diameter is compared with the reference outer diameter, and the diameter difference is determined. A moving amount Y calculated by integrating a predetermined coefficient with respect to the diameter difference is stored, and just before the corresponding glass tube 1 reaches the position of the cutter 5, the moving amount Y of the movable guide plate 3b by the moving amount Y is stored. Have the height automatically adjusted. As a result, as shown in FIG.
The large-diameter glass tube 11 urged to the side is positioned by the movable guide plate 3b at the point P1, and the small-diameter glass tube 12 is positioned by the movable guide plate 3b at the point P2. As a result, the collar length L of the glass tube 1 cut by the cutter 5 has a value within a predetermined tolerance range regardless of the outer diameter of the glass tube 1.

FIG. 1C exaggerates the variation of the outer diameter of the glass tube 1 for the sake of convenience of explanation. It will be described as an example.

For example, assuming that the small-diameter glass tube 12 has a reference outer diameter, the glass tube 11 having a larger diameter than the reference outer diameter is
If the position in the tube axis direction positioned in contact with the movable guide plate 3b remains at the position P2 of the reference outer diameter, the position of the inclined surface 1b contacts the position P2 in FIG.
Will be positioned at the position shifted in parallel by X to the left side in the axial direction, and as a result, the collar length L will be cut to a length (LX) shorter than that of the reference outer diameter. Become. Therefore, if the height of the movable guide plate 3b is increased by the movement amount Y, the large-diameter glass tube 11 and the reference outer-diameter glass tube 12 do not move in the tube axis direction, and have substantially the same collar length L. Will be disconnected.

When the large-diameter glass tube 11 is considered to have a reference outer diameter, the glass tube 12 having a smaller diameter than the reference outer diameter has a position in the tube axis direction which is positioned in contact with the movable guide plate 3b. If the position P1 of the reference outer diameter remains at the position P1, the inclined surface 1b reaches the position where the inclined surface 1b comes into contact with the position P1 in FIG.
Is shifted to the right side in the axial direction by X, and as a result, the collar length L is cut to a length (L + X) longer than that of the reference outer diameter. Therefore, if the height of the movable guide plate 3b is reduced by the movement amount Y, the small-diameter glass tube 12 and the reference outer-diameter glass tube 11 do not move in the tube axis direction, and have substantially the same collar length L. You will be disconnected.

The amount of adjustment of the height of the movable guide plate 3b may be approximately half of the diameter difference with respect to the reference outer diameter, but strictly speaking, the amount of movement of the axis and the shoulder of the throttle portion 1a are strictly required. In consideration of the inclination angle of the inclined surface 1b and the like, a value obtained by integrating a predetermined coefficient into the diameter difference is applied.

In the above embodiment, only the guide plate near the cutter 5 is movable in the vertical direction. However, it may be movable in the tube axis direction. In addition, the cut burner 4 can locally heat the cut region corresponding to the size of the outer diameter of the glass tube 1 so that unnecessary portions are not heated. This is preferable because the propagation region of the crack due to the thermal shock when the cutter 5 is brought into contact can be limited to a narrow range, and the flatness of the end face of the cut can be improved. Instead of making the guide plate movable, the position of the cutter 5 in the tube axis direction may be automatically adjusted. In that case, it is preferable to adjust the position of the cut burner 4 similarly.

In the above embodiment, the outer diameter D3 of the glass tube 1
Although the difference between the diameter and the reference outer diameter is used as the adjustment amount, the outer diameter ratio may be used.

[0028]

According to the first aspect of the present invention, the cutting position of the glass tube by the cutter can be cut so that the collar length falls within a predetermined tolerance range with respect to the outer diameter of the glass tube. Thereby, the non-defective rate of the glass tube can be greatly improved.

According to the second aspect of the present invention, the height of the guide plate in the vicinity including the installation position of the cutter can be adjusted while the cutter is fixed at a fixed position, so that the outer diameter of the glass tube can be adjusted. Thus, the glass tube can be cut such that the collar length falls within a predetermined tolerance range, thereby easily improving the yield rate of the glass tube.

Further, according to the third aspect of the invention, the height of the guide plate near the cutter can be adjusted while the cutter is fixed at a fixed position, so that the structure of the apparatus can be simplified and the glass can be simplified. The non-defective rate of the pipe can be greatly improved.

[Brief description of the drawings]

1A and 1B are a schematic side view and a plan view of a glass tube cutting device according to the present invention, and FIG. 1C is an explanatory diagram of a cutting method according to the present invention.

FIG. 2A is an explanatory diagram of main dimensions of a glass tube after cutting, and FIGS. 2B and 2C are an enlarged side view and a cross-sectional plan view of a conveying unit.

FIG. 3 is a flowchart showing the operation of the cutting method of the present invention.

4A and 4B are a schematic side view and a plan view of a conventional glass tube cutting apparatus, and FIG. 4C is an explanatory view of a conventional cutting method.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 glass tube 1a squeezing section 1b inclined surface 11 large-diameter glass tube 12 small-diameter glass tube 2 transport means 3a fixed guide plate 3b movable guide plate 4 cut burner 5 cutter 6 outer diameter measuring means L color length D1 base line diameter D3 outer diameter

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshihiko Tamura 2-7-1 Hararashi, Otsu City, Shiga Prefecture Nippon Electric Glass Co., Ltd. F-term (reference) 4G015 FA06 FB03 FC02 FC02 FC04 FC14

Claims (3)

[Claims] 1. A glass tube having a squeezed portion having a base line diameter formed on an inclined surface is movably supported in the tube axis direction, and is conveyed in a direction perpendicular to the tube axis while being rotated and conveyed. In the direction, the inclined surface of the narrowed portion is brought into contact with the guide plate to position the glass tube in the axial direction, and the narrowed portion of the positioned glass tube is heated by a cut burner. In a method for cutting a glass tube, which is cut by contacting a cutter, measuring an outer diameter of the glass tube, and correspondingly, a position of a base line diameter of the inclined surface of the glass tube and a cutting position of the cutter of the glass tube. A method for cutting a glass tube, wherein the distance from the glass tube is made substantially constant. 2. A method of measuring an outer diameter of a glass tube, and adjusting a guide plate to a measured value of an outer diameter such that a distance between a base line diameter of the inclined surface and a cutting position of the cutter of the glass tube is substantially constant. The method for cutting a glass tube according to claim 1, wherein the glass tube is displaced by an adjustment amount obtained by comparison with a reference outer diameter. 3. A conveying means for conveying a glass tube having a throttle portion having a base line diameter formed on an inclined surface so as to be movable in the tube axis direction and conveying the glass tube in a direction orthogonal to the tube axis while rotating the glass tube. A guide plate for positioning the position of the glass tube in the tube axis direction by contacting the inclined surface of the narrowed portion of the glass tube which is conveyed and moved in the tube axis direction, and a cut burner for heating the positioned narrowed portion of the glass tube And a cutter for cutting the glass tube in contact with the heated squeezed portion, an outer diameter measuring means for measuring an outer diameter of the glass tube in advance, and a position of a baseline diameter of the inclined surface. And a guide plate that is displaced by an adjustment amount obtained by comparing a measured value of the outer diameter measuring means with a reference outer diameter so that a distance between the outer diameter and the cutting position of the cutter of the glass tube is substantially constant. Cutting device of the glass tube characterized by.