JPS61256926A - Method for supplying fused glass gob - Google Patents

Abstract

PURPOSE:To make the supply of gobs at long supply intervals possible by extruding a specified amt. of fused glass from the orifice in the lower part of a glass smelting furnace and shearing the same with a shear then closing the bottom surface of the orifice with a supporting plate. CONSTITUTION:The glass flow extruded by a plunger 1 from the orifice 4 provided in the lower part of the glass smelting furnace 3 is sheared by the shear 5 provided below the above-mentioned orifice 4 and the specified amt. of the fused glass gob is supplied into a metallic mold (not shown) provided below. After the above-mentioned glass flow is cut, the shear 5 is retreated and the supporting plate 6 is advanced to close the bottom surface of the orifice 4 and the glass flow is maintained by the top surface of the supporting plate 6 until the next glass flow is extruded. The plate 6 is attached to the top end of the arm 7 of a rotary actuator 8 and is made retreatable to the position where the falling course of the gob is averted and where the plate does not interfere with the shear 5. Cooling air, etc. are further supplied via a cooling pipe 10 and is constituted adjustably in temp. in such a manner that the glass does not burn.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for supplying molten glass gobs (hereinafter referred to as gobs) used for manufacturing glass products, specifically glass tableware, etc. The present invention relates to a method for supplying a molten glass gob that is suitable when the viscosity of the glass base to be used is low or when the supply interval is relatively long.

[Prior Art] A plunger gob feeder is known as one of the devices and methods for supplying a required amount of molten glass material to a molding machine during the molding process of glass products.

A conventional plunger gob feeder feeds the glass substrate melted in a glass melting furnace by reciprocating the plunger vertically through a link driven by a cam mechanism at one end, which is installed at the bottom of the furnace. A constant stitch is extruded from an opening (hereinafter referred to as an orifice), and then cut off using a cutting device called a shear (5hear) installed at the bottom of the orifice. By repeating this process, the stitch is finished! It supplied gobs to the machine periodically. However, the shape and temperature of the gob supplied to the molding machine greatly affect the quality of the molded product. In other words, if the gob shape is inappropriate for the molded product, it may cause product defects such as uneven product thickness or the inability to obtain the desired product shape, and if the gob temperature is low, the area around the orifice may deteriorate over time. Crystallization of the glass progresses, causing defects such as loss of smoothness on the gob surface or inability to obtain the desired gob shape. Therefore, when operating a plunger gob feeder, in order to supply the optimal gob for molding, the plunger stroke, the distance from the orifice to the bottom dead center of the plunger movement, the plunger diameter, the orifice diameter, and the height of the tube from the furnace are required. Adjustments are made to the cutting timing, glass temperature, etc.

[Problems to be Solved by the Invention] Since the conventional plunger gob feeder forms gobs by the above-mentioned operation, there are cases where the gob feeding interval is relatively large (long distance) or the temperature of the glass to be fed changes. If is high,
In other words, if the molten glass has a low viscosity, the glass flow will drip from the orifice between one cutting of the gob with the shear and the next cutting, resulting in the gob shape becoming elongated to less than the desired gob diameter, or the gob becoming narrower than the desired gob diameter. There was a problem in that part h<' was missing, making molding impossible. In such cases, in order to increase the suction force of the plunger, ■ Plunger movement distance (plunger stroke)
■ A method to increase the viscosity by lowering the temperature of the glass ■ A method to shorten the gob forming interval by molding disposable gobs and increasing the number of gobs supplied compared to the required number of gobs. However, in method (■), if the plunger tip is too far away from the orifice, the suction effect cannot be expected, and there is a limit to how well the glass can be prevented from dripping. In addition, the method (2) causes crystallization of the glass at the orifice, etc., and causes devitrification, which is a major defect in the product. Furthermore, method (■) was inefficient in terms of materials and was extremely untested.

The present invention was made to improve the problems of the conventional method, and the first purpose is to enable long gob supply intervals, and the second purpose is to enable gob supply at high temperature gobs. The purpose is to prevent devitrification of the glass by supplying the glass, and the third purpose is to stabilize the gob shape required for molding.

[Means for Solving the Problems] In order to achieve the above object, the present invention has a method of cutting the glass flow pushed out by a plunger from an orifice provided at the bottom of the glass melting furnace with a shear provided below the orifice. In the method of supplying the molten glass gob of the demarcation mother into the mold, after cutting the glass flow, the shear is retreated, and then the lower part of the orifice is closed until the plunger is lowered and the glass flow is pushed out of the orifice. The glass flow is held on the upper surface of the supporting plate which is advanced in this manner.

The support plate must be located at a position where it does not interfere with the sill when cutting the glass substrate, and must also be provided so as to avoid the course of the gob falling. Further, while the plate is holding the glass flow, it is necessary to adjust the temperature of the plate to an appropriate temperature using cooling means such as air so that the glass does not burn onto the plate.

[Example] The present invention will be described below based on the drawings. FIG. 1 is a front view of an apparatus for implementing the method of the present invention, and FIG. 2 is a side view thereof. In FIG. 1, reference numeral 1 is a plunger, 2 is a tube, 3 is a melting furnace, and 4 is an orifice, and the plunger 1 and tube 2 are arranged on the orifice.
Although not shown, the plunger 1 reciprocates in the vertical direction by a link driven by a cam.

By descending, the plunger 1 pushes out the molten glass base from an orifice 4 provided at the bottom of the melting furnace.

The glass flow extruded from the orifice 4 is cut off by a shear 5 provided below the orifice, and is injected into a mold (not shown).

After cutting the glass flow, the shear 5 is withdrawn. The glass remaining in the orifice 4 is held by a support plate 1-0 provided below the melting furnace, as shown in FIG. 1, until the plunger 51 is then lowered to force the glass flow out of the orifice. The support plate 6 is advanced from the standby position toward the lower surface of the orifice to close the orifice 4, as shown by the imaginary line in FIG.

As shown in FIG. 2, the support plate 6 has an actuator 8 attached to a fixing member 9 at the lower part of the melting furnace, and this actuator prevents the fall course of the gob 11 and closes the position where it does not interfere with the shear 5 and the lower surface of the orifice. It is held so that it can move in and out between positions. In this embodiment, a support plate 6 is attached to the tip of an arm 7 that swings by a predetermined angle by a rotary actuator 8. The timing of this behavior toward the support play 1 is closely related to the behavior of the plunger 1 and shear 5.

Note that when supporting the glass flow, the support plate 6 is cooled with air or the like to prevent it from burning onto the glass substrate.
Constructed to maintain an appropriate temperature range. Therefore,
In this embodiment, a cooling pipe 10 through which cooling air flows is attached to the support plate 6.

[Effects of the Invention] As explained above, when the method of the present invention is used, the glass substrate left in the orifice after the glass flow is cut is removed until the plunger descends and pushes the glass flow out of the orifice. Since the glass is supported by the soil surface of the support plate which is advanced so as to close the bottom surface of the orifice, the glass can be prevented from hanging down from the orifice and the gob shape can be made into a good shape. Even when the molten glass has low viscosity, it is possible to lengthen the gob supply interval, and it is also possible to supply gobs with low viscosity and without devitrification.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of an apparatus for implementing the method of the present invention, and FIG. 2 is a side view of the same. 1... Plunger, 2... Tube, 3... Melting furnace, 4... Orifice, 5... Shear, 6...
Support play (~, 7... Arm, 8... Actuator, 9... Fixing member, 10... Cooling pipe, 11...
・Gob. Applicant Hoya Co., Ltd.

Claims (1)

[Claims] 1. A method of supplying a fixed amount of molten glass into a mold by cutting the glass flow pushed out by a plunger from an orifice provided at the bottom of a glass melting furnace with a shear provided below the orifice. After cutting the glass flow with the shear, the shear is moved back, and the plunger is then lowered to push the glass flow out of the orifice. A method for supplying a molten glass gob characterized by holding a molten glass gob. 2. The method for supplying a molten glass gob according to claim 1, wherein the temperature of the support plate is adjusted so that the glass does not burn onto the support plate at least while the glass flow is maintained. 3. When cutting the glass stream, the support plate avoids the falling course of the gob and is held back in a position where it does not interfere with the shear, and after cutting, the support plate is advanced and held directly below the orifice. Supply method.