JPS61181030A - Device for controlling circular glass tube formation furnace - Google Patents

Abstract

PURPOSE:To keep a heating furnace in a condition appropriate for annular formation, by putting a timer in operation for a set time to disconnect a generated heat quantity controller and a heating section from each other to avoid the influence of the operation of the controller. CONSTITUTION:As soon as a PID temperature controller 1 generates an output signal, a timer 9 starts acting. As soon as the timer 9 finishes acting, another timer 10 starts acting to disconnect the PID temperature controller 1 and a gas flow rate controller 3 from each other. During the disconnection, the gas flow rate controller 3 does not act even if the PID temperature controller 1 generates the output signal. During the disconnection, an annular glass tube formation furnace 7 gradually returns to the original condition because of the first time of gas flow rate change. The furnace 7 remains in the condition until the time 10 finishes acting. The furnace 7 returns to a normal production condition after the timer 10 finishes acting. The furnace is thus kept in a condition appropriate for annular formation. As a result, the efficiency of work is enhanced and the ratio of defectiveness is diminished by 30%.

Description

Detailed Description of the Invention [Field of Application of the Invention] The present invention relates to a process of heating and softening a straight glass tube and forming it into an annular shape, such as in the manufacture of annular fluorescent lamps, and in particular, the present invention relates to a process of heating and softening a straight glass tube to form it into an annular shape, and in particular, a process in which the heating state of the glass tube is kept constant. The present invention relates to a device for heating a glass tube suitable for maintaining the temperature of the glass tube.

[Background of the invention]

In the conventional device, the heat generating part and the heat generating amount adjusting part are directly connected, and the heating value adjusting part emits a signal depending on the state of the furnace body to control the heating part.

However, when the condition of the furnace body changes, even if the control section issues a signal to change the calorific value, it takes a considerable amount of time for the condition of the furnace body to return to its original state, so the control section must be sent several times. Each time a crossing signal is issued.

The amount of heat generated was changing.

On the other hand, the heating state of the glass tube returns to a state satisfactory for forming a ring due to the first change in the amount of heat generated, but the amount of heat generated changes further, making it impossible to form it into a regular ring shape. A lot of things happened.

In addition, related to this type of device.

Published Practical Application 1978-70678, etc. are listed.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an adjustment device that eliminates the influence of the operation of the adjustment section as described above and maintains the heating furnace in a state suitable for ring formation.

[Summary of the invention]

To achieve this purpose, when the state of the furnace body changes and the calorific value adjustment unit issues the first signal, a timer starts operating.
By disconnecting the heat generating unit and the heat generating unit for a set time, the signal is not transmitted to the heat generating unit until the time is up. During this time, the furnace body gradually returns to its original state. Also,
If the furnace body has not returned to its original state when time-up occurs, the furnace body can be maintained in a state suitable for ring formation by repeating the above operations.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a system diagram of a glass tube heating furnace, and FIG. 2 is a time chart of a timer used in the present invention.

In FIG. 1, the state of the furnace body 7 is input as a temperature change using PID@Adjuster 1 Heat Adjustment 1:6.

Further, the gas flow rate control device 3 controls the flow rate of the gas based on the output signal of the PID temperature controller, and the gas is combusted by the gas burner 5.

In FIG. 2, the timer 9 starts operating (timer 9 timing O'N) at the same time as the PID temperature controller 1 emits an output signal (PID temperature controller transmission timing 8ON). Further, at the same time as the timer 9 times up (timer 9 timing times up), another timer 10 starts operating (timer 10 times ON).

Note that the two timers 9 and 10 in FIG. 2 are built into the adjusting device 2 according to the invention.

Suppose now that the state of the furnace body 7 changes, the thermocouple 6 reacts, and the PID temperature controller 1 emits an output signal in response. At the same time, the timer 9 built into the adjustment bag M2 according to the present invention starts operating.

Until timer 9 times up, PID thermometer 1
The output signal is directly transmitted to the gas flow rate control device 3. Since the gas flow rate control device used in this embodiment operates only while receiving a signal and changes the gas flow rate, the maximum value of the control amount can be set by the time set by the timer 9.

At the same time as the timer 9 times up, the timer 10 starts operating, and the PID temperature controller 1 and the gas flow rate control device 3 are disconnected. While the PID @ controller 1 heat controller 1 flow rate controller 3 is disconnected, the gas flow controller 3 does not operate even if the P, ID temperature controller 1 issues an output signal. During this time, the furnace body 7 gradually returns to its original state due to the first gas flow rate change.

This state continues until the timer 10 times up, after which the normal production state returns. Also, timer 10
When the time has elapsed, if the state of the furnace body 7 has not returned to its original state and the PID temperature controller 1 is emitting an output signal, the above steps are repeated.

According to this embodiment, even if the PID temperature controller 1 issues an output signal several times, only the first output signal is transmitted to the gas flow rate control device 3.

The conditions necessary for ring forming can be maintained, which has the effect of improving yield and improving workability.

〔Effect of the invention〕

According to the present invention, even if the heat generation amount adjusting section issues a signal several times, only the first signal is transmitted to one heat generation section.

Therefore, the annular glass tube forming furnace can be maintained in a state suitable for forming agglomerates, which has the effect of improving workability and reducing the defective rate by 30%.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of a glass tube heating furnace, and FIG. 2 is an example of a time chart of a timer used in the present invention. DESCRIPTION OF SYMBOLS 1... PID temperature controller, 2... Adjustment device according to the present invention, 3... Gas flow rate control device, 4... Piping,
5... Gas burner, 6... Thermocouple, 7... Furnace body,
8... PID temperature controller transmission timing, 9... Timer 9 timing, 10... Timer 10 timing.
−1゜Representative Patent Attorney Katsuo Ogawa, 2) −＼＋／

Claims (1)

[Claims] A heating furnace consisting of a heat generating part for heating a straight glass tube, a furnace body with the heat generating part disposed on a side surface, and an adjusting part for adjusting the amount of heat generated by the heat generating part, in which the amount of heat generated is changed by the adjusting part. A control device for an annular glass tube forming furnace, characterized in that a timer is provided to maintain the connection between the heat generating part and the control part for a certain period of time when a signal is issued to disconnect the heat generating part and the control part for a certain period of time, and a timer to disconnect the connection for a certain period of time after the connection is maintained. .