JPH03285832A - Method and device for cutting molten glass for forming glass bottle and cutting edge utilized therefor - Google Patents

Abstract

PURPOSE:To control the shape of a gob and to reasonably increase the number of times for cutting and to prolong the service life of a cutting blade by turning a pair of cutting blades in a looped shape in the falling direction of molten glass while maintaining the cutting blades in a nearly horizontal state just under a gob feeder. CONSTITUTION:Molten glass 18 falling from the inside of a gob feeder receives one time of cutting by turning at every cycle of the cutting blades 1a, 1b whose main body part 24 is made platelike. The cutting blades start from the points A, A' of the circular loca 19a, 19b thereof and are raised. Then while the cutting blades are lowered, these are advanced toward glass 18. The blades start cutting from both side faces of glass while holding a horizontal state. The blades are crossed in the central position of glass and cutting of glass is completed. Thereafter while the blades are retreated, lowering is continued. The blades are raised and returned to an original point. At this time, when glass 18 is stopped, gob is formed into 22. When glass 18 is lowered at the same velocity as the descending velocity of the blades at the time of cutting, gob is formed into 23. When the blades are lowered at a velocity higher than the descending velocity of glass, the cut face of glass is made to an inverse conical shape having various length.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method and apparatus for cutting molten glass flowing down from a gob feeder in order to supply a predetermined gob to a forming process in glass bottle manufacturing, and an apparatus therefor. Regarding cutting blades.

[Prior art] When manufacturing glass bottles such as beer bottles and milk bottles,
Predetermined raw materials are mixed and melted in a melting furnace to produce molten glass, which is passed through a throat section and a working chamber and then supplied to a feeder section. A gob feeder is provided at the tip of the tweeter section. This gob feeder is as shown in Figure 5.
An orifice 33 provided in the lower part of the spout 31 for causing the molten glass 32 to flow down, a plunger 34 provided above the orifice 33 so as to be able to rise and fall freely, a cylinder 35 provided around the plunger 34, and a portion below the orifice 33. A pair of horizontally reciprocating cutters (blade) 3 arranged in
It consists of 7. The falling glass is cut with the cutter to produce a gob (lump of molten glass) 36.

The molten glass 32 adjusted to a desired viscosity (for example, 1027 to 1085 poise) and sent to the spout 3 is regulated by the cylinder 35 to a glass flow rate according to the weight and shape of the bottle, and is regulated by the downward movement of the plunger 34. Orifice 33
(Fig. 5(a)), and the cutter 3 is ejected at a predetermined position.
It is cut into one gob 36 at point 7, and is dropped and supplied to the mold of the bottle making machine waiting below (Fig. 5(b) (C
)reference). In the forming process in the bottle making machine, the material is formed into a parison using a set mold, and then formed into a bottle shape using a finishing mold.

The stroke amount and speed of the plunger are adjusted by a cam mechanism, thereby adjusting the gob supply timing and gob shape. The orifice also has the function of determining the maximum diameter of the bottle. Furthermore, the cutting timing of the cutter that cuts the glass flowing down from the orifice is controlled by a cam mechanism.

In addition, the cutter (blade) that cuts the molten glass is, for example,
As shown in FIG. 6, it has a V-shaped blade surface 38 at the tip, and a portion 39 of a constant width including the blade surface 38 is formed so as to swell from the other blade body 40 (FIG. 6(b) ), and as shown in figure (c), a relief portion 41 is provided at the cutting edge. In use, a pair of the above-mentioned cutters are placed facing each other in a back-to-back posture, and the cutters are moved forward, crossed, and retreated in the horizontal direction.

[Problem to be solved by the invention] However, when cutting molten glass flowing down from an orifice, for example, when the opposing blades move horizontally and intersect while the molten glass is flowing down, the blades Since the glass stops for a short time when crossing, the glass is flowing down even during this stop, which causes wrinkles in the glass on the top of the blade, which can cause flaking of defective products during molding. (This effect is strong because the glass is cooled when it is retracted.) In particular, the outer edge of the glass is cooled and tends to cause thermal distortion. For this reason, at present, when the plunger inside the cylinder is pulled up, the molten glass is momentarily stopped, and the blade is moved to cut the glass at this timing.

However, in reality, there is a time difference between the pulling up of the plunger and the cutting operation by the blade, and by adjusting this time difference in a precise manner, the desired shape of the gob can be obtained. That is,
If the time difference is small, the gob will be thick, and if the time difference is large, the gob will be thin, and a great deal of skill is required to make this adjustment.

Further, since the falling glass is a viscous substance, it is impossible to completely stop the glass by just pulling the plunger up. Therefore, it intersects and stops at the center of the flowing glass,
The glass that comes into contact with the horizontally receding blade will wrinkle and the area in contact with the blade will cool rapidly. When this cooling point is vacuumed at the neck ring position during subsequent molding, it generates a large thermal internal stress, which causes thermal strain.

In addition, when increasing the cutting capacity, conventionally the plunger speed is increased, but this also increases the reciprocating speed of the blade, which increases the inertia of the blade and requires readjustment of the cam mechanism. In order to speed up the operation and increase cutting capacity, high structural rigidity is required, and there are practical limits.

Next, as for cutting blades, as shown in Figure 6, conventional blades have complicated shapes and are expensive to manufacture, and it is difficult to use materials with excellent wear resistance such as carbide or ceramics. be. In addition, the cutting edge had to be reused after being ground to a certain level due to severe wear, but it required frequent replacement, reducing productivity. Moreover, since the cutting edge is provided with a relief part 41 shown in FIG. 6(c), the position of this relief part changes when grinding during wear, and it is necessary to finely adjust the height of the cutting edge each time. In addition, since the pair of cutting blades are used back to back, there is a difference in inertia, which affects the fall of the gob and causes it to fall diagonally, so it is necessary to provide a guide, etc. There is a point.

The present invention solves the problems of the prior art, supplies gobs with an optimal and desired shape to the next process, and improves the productivity and quality of glass bottles by cutting molten glass. It is an object of the present invention to provide a method and a cutting device for carrying out the method, and at the same time to provide a practical cutting blade with a long life and a simple shape for use in the method.

[Means for Solving the Problems] The cutting method of the present invention to achieve the above object is a method for cutting molten glass for glass bottle forming, in which molten glass flowing down from a gob feeder is cut by at least a pair of opposing blades directly below the gob feeder. In the method of cutting glass, the pair of blades are rotated in a loop in the direction of flow of the molten glass while maintaining them in a substantially horizontal state, so that the opposing blades are centered on the flow line of the molten glass when viewed in plan. It is characterized by symmetrical advancement, crossing, and retreating, and cutting the molten glass without stopping the blades at the crossing stage of the opposing blades.

Further, in the present invention, it is also possible to arbitrarily change the cutting shape by adjusting the speed of the blade at the time when cutting the molten glass starts in the rotation locus of the blade.

Next, the molten glass cutting device of the present invention includes a pair of opposing holders, at least a pair of opposing blades attached to the holders in a substantially horizontal state, and the pair of blades sandwiching the flowing molten glass. It is characterized by comprising a holder rotation drive mechanism connected to the holder in order to perform symmetrical forward, cross, and backward movements.

The above-mentioned holder rotation drive mechanism is composed of two crankshafts provided above and below each holder that perform the same motion, and a gear that imparts symmetrical motion to the corresponding crankshafts of the opposing holders. It is preferable.

Furthermore, in the present invention, as the blade used in the above-mentioned cutting method, a molten glass cutting blade is used, which is characterized in that the V-shaped blade surface at the tip and the blade main body following the V-shaped blade surface are formed into a flat plate shape. This is desirable.

[Operation] In the present invention, when cutting flowing molten glass, a pair of opposing horizontal blades performs a symmetrical rotational movement following a predetermined vertical loop-shaped locus. Assuming that it starts from the farthest point, the advancing blade continues its advance from the top of the loop to the bottom and begins cutting from the side of the molten glass. Next, the opposing blades continue to descend in a horizontal position, approach each other, intersect at the center position of the molten glass (cutting of the glass ends at this position), and then continue to descend while separating from each other without stopping. It escapes from the glass and rises again from the lowest point of the loop, completing one cycle.

As described above, in the present invention, the blade moves along the flowing molten glass during the cutting process, and the speed thereof may be the same as or different from the flowing speed of the molten glass.

Further, since the blade according to the present invention performs the above-mentioned unique glass cutting operation, unlike conventional blades, a blade having the simplest shape is sufficient.

[Example] The present invention will be explained below based on embodiments shown in the drawings.

FIG. 1 shows an example of a double-blade type cutting device equipped with two pairs of blades. Blades 1a, 2a and lb, 2b are as shown in the diagram.
They are fixed to a pair of cutting holders 3a and 3b with bolts in a substantially horizontal state facing each other. As shown in the figure, the pair of holders 3a and 3b face each other with their axes substantially parallel to each other, and each holder has a longitudinally elongated cross section, and the blade is removably attached at an intermediate position. There is. Further, the holders 3a and 3b each have two upper and lower crankshafts 4a,
The holder is supported in a cantilevered manner at 5a, 4b, and 5b, and the holder is mounted at one end of the crankshaft in a constant trajectory without changing its cross-sectional orientation, that is, while maintaining the blade in an almost horizontal state. A holder rotation drive mechanism for rotating the holder in the vertical direction (downward direction of the molten glass) is connected to the holder.

As shown in the figure, the holder rotation drive mechanism includes a wooden crankshaft 4a (the other three crankshafts 4b, 5a, 5
(b) is connected to the crank main shaft 8a via a counterweight 6a, and this main shaft is attached to a gear box 14 with an oil seal 0 and a bearing 11 interposed therebetween, and a shaft for rotating the crank shaft is installed in the gear hook 14. Various gears are arranged to do this. That is, each crankshaft 4a, 4b
, 5a, 5b fixed hemical gear +2a, 13a, 1
2b, 13b, and a drive gear 15 that meshes with these gears.
and an intermediate gear J6, and the drive gear I5 is connected to the ACC thermomotor 17, which is a drive source. In this way, the pair of holders 3a, 3b are attached to the crank main shaft 8a.
, 9a, 8b, and 9d are vertically rotated at a constant radius and symmetrically with respect to the central axis of the flowing molten glass.

Further, the blades 1a, 2a, lb, 2b are attached to the holder 3a described above.
.

Corresponding to the operation of 3b, it similarly rotates in the vertical direction at a constant radius, but when one cycle of this operation is viewed in plan, the opposing blades move forward with respect to the molten glass 18, and the blades rotate at the center of the molten glass. A predetermined operation of crossing (see the broken line position in FIG. 1; the molten glass is cut at this position) and retreating is performed.

FIG. 2 schematically shows various gear arrangements for achieving the unique movement trajectory of the blade, which is a feature of the present invention.

For convenience, a pair of blades was used. The drive gear 15 rotated by the drive motor 17 has one holder (left side in the figure).
Two crankshaft rotation gears 12b, 1 that rotate 3b
3b and one intermediate gear 16 mesh with each other, and the intermediate gear 1
6 is the other holder (on the right side in the figure) 2 which rotates 3a
The crankshaft rotating gears 12a and I3a are meshed with each other. Each crankshaft 4a.

5a, 4b, and 5b are counterweights 6a for smooth rotation and for balancing weight during rotation.

6b, 7a, and 7b are interposed.

Therefore, when the drive motor 17 is operated to rotate the drive gear I5 in the direction of the arrow (counterclockwise), the gear 12b meshes with the drive gear I5.

13b is a left crankshaft 4b that rotates clockwise.

5b in the same direction, the holder 3b also rotates, and the blade 1b follows a clockwise circular trajectory 19b with a constant radius.
draw On the contrary, the right gear 12a via the intermediate gear 16
, 13a rotate counterclockwise, rotate the holder 3a in the same direction, and further cause the blade 1a to have a circular locus 19 in the counterclockwise direction.
A will be given. These circular loci 19a, 19b
are symmetrical across the molten glass flow line 20.

In addition, in FIG. 1(C), a cooling oil spraying mechanism for cooling the blade surface is provided.

That is, oil spray nozzles 21 are disposed facing both sides of the eight blades, and each part of the pipe that supplies oil to the nozzles 21 is connected to an external supply source.

Further, FIG. 4 shows the shape of a blade suitable for use in the present invention, and the V-shaped cutting edge 25 at one end of the blade body 24 is
It is formed on the same plane as the blade body 24, and has a simple shape with no protuberance or relief at the cutting edge, unlike the conventional blade shown in FIG. In use, as shown in FIG. 4(a), a pair of opposing identical blades are used back to back.Next, the operation of cutting molten glass using the apparatus of the embodiment will be explained.

The molten glass in the gob feeder begins to flow down intermittently from the orifice by lowering and raising the plunger by driving the plunger motor, but by driving the AC servo motor in conjunction with the start signal of the motor, each gear and the crankshaft are , imparts rotation to the blade every cycle via the holder. This causes the molten glass to undergo one cut per cycle directly below the gob feeder.

To explain the state of cutting molten glass with reference to FIG. 3, the opposing blades start from the grain positions A and A' of the circular loci 19a and 19b of the blades, and move forward toward the molten glass 18 while descending from an ascending position. Start cutting while maintaining the horizontal state from both sides of the glass, cross the center of the molten glass (wrap amount is about 1 to 2 mm), finish cutting the glass, and then move backwards after passing the forward limit position. It continues to descend while moving, and then moves upward to return to the initial A and A' grain positions. Assuming that the molten glass is stopped at this time, the glass will be cut into a nearly rectangular shape along the locus of movement of the blade when viewed from the front as shown in the figure, and the gob will be like 22, but the cut If the molten glass were to descend at the same speed as the blade, the glass would be cut in a nearly horizontal plane and the gob would be 23. In addition, when the blade is lowered at a speed faster than the glass descending speed, the glass cutting surface can be made into an inverted conical shape with various lengths, and if the blade is lowered slower than the glass descending speed, the glass cutting surface can be made into an inverted conical shape. It is also possible to obtain a cut surface having . Therefore, by relatively changing the glass lowering speed and the rotation speed of the blade, a gob having a desired shape can be obtained.

In addition, in the present invention, the speed of the blade at each stage in one cycle can be precisely controlled by adjusting the pulses of the AC servo motor. For example, from the start of cutting to the end of cutting, the speed is set to obtain the desired gob shape, and after cutting, the speed is increased to avoid contact with the glass, and the speed is decreased outside the range of glass flow. The time can be controlled so that it is always the same. Of course, it is also possible to perform similar control by interposing an elliptical gear on the drive shaft of the motor without using pulse adjustment.

Further, in the embodiment, the vertical rotation locus of the blade is circular, but any locus other than a circle may be used as long as it is a loop-shaped locus.

Further, in the illustrated example of the present invention, the molten glass is caused to flow down from the gob feeder using a plunger and cut. Of course, it can be similarly applied to.

[Effects of the Invention] According to the cutting method of the present invention described above, molten glass is cut by a blade that does not stop during the cutting process while following the glass flowing speed, and after cutting, Since the blade can be retracted without making contact with the glass, the molten glass can be cut smoothly and without difficulty, and contact with the glass can be minimized (contact time is about half that of conventional methods). can),
Defects such as wrinkles can be reduced. Another advantage is that the shape of the gob can be easily adjusted.

Further, according to the cutting device of the present invention, it is possible to carry out the above-described method in a suitable state, and moreover, the blade can be rotated rather than reciprocated, and the blade can be structurally adapted to the operation of the plunger. It is possible to easily link the rotation of the
It is possible to easily increase the number of cuts and increase production capacity.

Furthermore, compared to conventional blades, the blade of the present invention has a less complicated shape, requires less load on the blade during operation, and has a longer lifespan (according to experiments conducted by the inventors, In addition, there is the advantage that materials with excellent wear resistance such as carbide or ceramics can be used.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the cutting device according to the present invention, (a)
is a plan view, (b) is a side view, and (C) is a front view. FIG. 2 is a schematic diagram showing a specific example of a gear mechanism for operating the blade, which is a feature of the present invention, and FIG. 3 is an explanatory diagram showing the state of cutting molten glass in the present invention. FIG. 4 is a perspective view of a cutting blade according to the present invention. Figure 5 (a) (b)
(c) is a schematic cross-sectional view showing a conventional gob feeder and its operation sequentially, Figure 6 shows a conventional blade, (a) is a plan view, and (b) is (a) (7) XX cross section. Figure, (C) is (a
) is a YY cross-sectional view of FIG. la, Ib, 2a, 2b--blade, 3a, 3b-catch ink holder, 4a, 4b, 5a, 5b-crankshaft,
6a, 6b, 7a, 7b - Counterweight, 8a
, 8b, 9a, 9b... Crank main shaft, 10-oi 7
1/ Seal, 11-...Bearing, 12a, 12J13
a. 13b...Heri Calgia, 14...Gearhox,
15-... Drive gear, 16-... Intermediate gear, 17...
Drive motor, 18... Flowing molten glass, 19a, 19
b--Blade movement trajectory, 20--Melten glass flow line, 21--Spray nozzle, 22.23--Gob, 2
4...Blade body, 25-...Blade edge patent applicant agent

Claims (1)

[Scope of Claims] 1. A method for cutting molten glass for glass bottle forming, in which molten glass flowing down from a gob feeder is cut by at least a pair of opposing blades directly below the gob feeder, the pair of blades being maintained in a substantially horizontal state. By rotating the molten glass in a loop in the direction of the flow of the molten glass, the opposing blades are moved forward, intersected, and retreated symmetrically around the flow line of the molten glass when viewed in plan, and the intersection of the opposing blades is A method for cutting molten glass for glass bottle molding, characterized by cutting molten glass without stopping a blade at any stage. 2. The cutting method according to claim 1, wherein the cutting shape is arbitrarily changed by adjusting the speed of the blade at the time of starting cutting of the molten glass in the rotating locus of the blade. 3. A pair of opposing holders, at least a pair of opposing blades attached to the holders in a substantially horizontal state, and symmetrical forward, intersecting, and retreating movements across the flowing molten glass between the pair of blades. 1. A cutting device for molten glass for glass bottle molding, characterized in that it comprises a holder rotation drive mechanism connected to the holder to perform the following steps. 4. The holder rotation drive mechanism consists of two crankshafts provided above and below each holder that perform the same motion, and a gear that imparts symmetrical motion to the corresponding crankshafts of the opposing holders. The cutting device according to item 3. 5. A blade for cutting molten glass for use in the cutting method according to claim 1, characterized in that the V-shaped blade surface at the tip and the blade main body following the V-shaped blade surface are formed into a flat plate shape.