JPH0348189Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention is a blow unit device that delivers a forming blow to glass that is supplied onto a sleeve and is to be formed by tube drawing, and in particular, a blow unit device that applies blow pressure to The present invention relates to a blow unit device for forming glass tubes that can continuously adjust pressure from positive pressure to negative pressure.

(Prior Art) In a glass tube drawing and forming apparatus using a damper machine, as shown in the second diagram, a molten glass 1 adjusted to an appropriate viscosity in a front hearth of a glass melting furnace is used.
1 is fed from the trough 12 onto the sleeve 13. The sleeve 13 has a downwardly inclined tip and rotates at a predetermined speed, while at the same time blowing out blow from the tip through a through hole provided in the shaft center. The molten glass 11 is formed into a tube according to conditions such as the inclination angle, rotational speed, and blowing pressure of the sleeve 13, and is pulled by a tube drawing machine (not shown) and slides on a number of guide rollers 14 to be drawn. be done.

The outer diameter of the glass tube drawn in this manner is adjusted by adjusting the blow pressure supplied to the glass tube through the sleeve.
For example, a control method that detects fluctuations in the outer diameter of a glass tube and adjusts the blow pressure using this detection signal;
Alternatively, the signal corresponding to the difference between the pipe outer diameter detection signal and a predetermined standard signal is used as the blow pressure setting signal, and the blow pressure is adjusted by the signal corresponding to the difference between this setting signal and the blow pressure detection signal. This method has been adopted and has been recognized to be quite effective in controlling the outer diameter of glass tubes.

Conventionally, a blow unit device for glass tube forming that supplies blow to a glass tube to be drawn has adjusted the blow pressure to correspond to the outer diameter of the glass tube using a blow source pressure regulating valve installed in the blow supply pipe. Blow is supplied to the sleeve, and the blow pressure is adjusted by adjusting the amount of blow released into the atmosphere by a blow pressure regulating valve disposed in a branch pipe branched from the blow supply pipe. ing. When the opening degree of the blow pressure regulating valve is increased, the blow pressure decreases, and when the opening degree is decreased, the blow pressure increases.

In order to draw and form a glass tube whose outer diameter is smaller than a predetermined limit, the blowing pressure must be changed from positive pressure to negative pressure. In such a case,
A negative pressure piping system using a blow suction device, such as a suction mixer, is connected to the blow supply pipe, and the blow is sucked from the blow supply pipe to form a negative pressure. The blow pressure at this negative pressure is also adjusted using the blow pressure regulating valve, and when the opening degree of the blow pressure regulating valve is increased, the blow pressure approaches from negative pressure to positive pressure. In the negative pressure state, the relationship between the degree of opening of the blow pressure regulating valve and the rise and fall of the blow pressure is opposite to that in the case of blow pressure regulation in the positive pressure state. For this reason, it is necessary to switch between positive and negative blow pressure settings at the work site.

(Problems to be solved by the invention) As mentioned above, the conventional blow unit device for forming glass tubes changes the blow pressure from positive pressure to negative pressure during tube drawing forming of glass tubes with small outer diameter. In this case, there are drawbacks such as the switching operation for connecting the blow suction device to the blow supply pipe is troublesome, and the blow pressure cannot be adjusted to around 0 pressure.

This invention was made to eliminate the above-mentioned drawbacks, and the blowing pressure for forming glass tubes can be easily switched from positive pressure to negative pressure without any troublesome operations. The object of the present invention is to provide a blow unit device for tube forming.

[Structure of the idea]

(Means for Solving the Problems) In order to achieve the above object, the present invention incorporates a blow suction device, such as a suction mixer, for sucking blow from a blow supply pipe into the blow unit structure. That is, a branch pipe having a blow pressure regulating valve and a blow suction device is attached to the blow supply pipe that supplies blow to the glass tube molding sleeve, so that the blow pressure can be continuously adjusted from positive pressure to negative pressure. This is a blow unit device for glass tube molding.

(Function) In this blow unit device, the blow is sucked from the blow supply pipe by a simple operation of activating the blow suction device provided branching off to the blow supply pipe, and the blow pressure in the sleeve is easily reduced to negative pressure. It can be switched and continuously adjusted from positive pressure to negative pressure. Further, there is no need to perform a troublesome blow pressure switching operation as in the conventional case.

(Example) An example of the present invention will be described with reference to the drawings.

In the glass tube drawing and forming apparatus (FIG. 2), molten glass 11 supplied onto a sleeve 13 from a trough 12 of a glass melting furnace is formed into a tube shape by blowing out from the tip of the sleeve 13 and is drawn into a tube.

FIG. 1 shows an example of a blow unit device of the present invention that supplies a forming blow to the above-mentioned glass tube drawing and forming device.

The blower 1 supplies a glass tube forming blow to a sleeve 13 connected to it via a blow supply pipe 2. A blow source pressure regulating valve 3 disposed in the blow supply pipe 2 adjusts the blow pressure in accordance with the outer diameter of the glass tube to be drawn. A branch pipe 4 branched from the middle of the blow supply pipe 2 has a blow pressure regulating valve 5, a suction mixer 6, and a regulating valve 7 interposed therebetween, and is supplied to the sleeve 13 by the blow pressure regulating valve 5. Adjust blow pressure. Further, when the blow pressure is set to negative pressure, the regulating valve 7 is opened and the blow in the blow supply pipe 2 is sucked by the suction mixer 6. 8 is a pressure gauge, and 9 is a differential pressure transmitter.

In the blow unit device configured as described above, the blower 1 is operated, and the blow is regulated to a predetermined pressure by the blow source pressure regulating valve 3 in accordance with the outer diameter of the glass tube through the blow supply pipe 2. It is supplied to the sleeve 13. Normally, when the blow pressure is a positive pressure, the blow pressure is adjusted so that when the blow pressure control valve 5 and the control valve 7 are closed, a blow pressure necessary and sufficient for the growth of the glass tube is obtained. Next, when setting the blow pressure to negative pressure in order to mold a glass tube with a small outer diameter, fully open the regulating valve 7 and open the blow pressure regulating valve 5, and the suction mixer 6 blows through the regulating valve 7. Blow is sucked from the supply pipe 2, and as the opening degree of the blow pressure regulating valve 5 is increased, the degree of suction increases, and the blow pressure shifts from positive pressure to negative pressure.
By the above operation, the blow pressure can be continuously adjusted from positive pressure to negative pressure.

Even if the blow pressure is positive or negative, the blow pressure fluctuation during glass tube drawing can be adjusted by operating the blow pressure control valve 5, but the detection signal of the glass tube outer diameter fluctuation or If the blow pressure regulating valve 5 is linked to a well-known blow pressure regulator that is activated by a detection signal of blow pressure fluctuations, the blow pressure can be automatically controlled.

[Effect of idea]

As described above, the present invention is a blow unit device for glass tube molding in which the blow supply pipe is equipped with a branch pipe having a blow pressure regulating valve and a blow suction device, and supplies the product to the sleeve without troublesome switching operations. Blow pressure can be continuously adjusted from positive pressure to negative pressure. It is also possible to adjust the blow pressure to around 0 pressure.

[Brief explanation of drawings]

FIG. 1 is a tube system diagram showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing a glass tube drawing and forming apparatus. 2... Blow supply pipe, 3... Blow source pressure control valve, 4... Branch pipe, 5... Blow pressure control valve, 6...
...suction mixer.

Claims (1)

[Scope of utility model registration request] In a blow unit device that supplies a molding blow to the glass that is supplied onto a sleeve to be drawn and formed, the blow supply pipe that supplies the blow to the sleeve is provided with a branch pipe that has a blow pressure regulating valve and a blow suction device. A blow unit device for forming glass tubes, which is characterized by the fact that it is equipped with a blow unit.