JPS59106799A - Method of controlling dropping amount of liquefied gas - Google Patents

Abstract

PURPOSE:To make it possible to carry out the programmed control of dropping amount of liquefied gas, by providing such an arrangement that the control of dropping amount corresponding to a line speed is made by controlling the valve opening degree of a dropping nozzle, and the controls in accordance with the other condition changes are made by controlling the internal pressure of a tank. CONSTITUTION:Liquefied gas in a reservoir tank 4 is dropped in a can 20 by pulling up a valve needle 9 by means of a solenoid 7. The position of an opening degree regulating pin 6 is controlled by a stepping motor 5. Meanwhile the internal pressure of the reservoir tank 4 is detected by a pressure detecting sensor 15, and a differential pressure transmitter 24 opens a solenoid valve 16 when the detected pressure is below a set value on a pressure setting unit 21. Therefore, evaporated gas in a main tank 1 flows into a gas discharge pipe line 14 through a pressure reducing valve 23 and a flow regulating valve 25 so that the internal pressure of the tank 4 is increased. The pressure setting unit 2 selectively sets the internal pressure of the tank in accordance with a desired value of can internal pressure, a distance between the LN2 dropping position and the winding and fastening position, and a charging amount of content.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dripping system system for applying internal pressure to cans, and to a device for dripping liquefied gas just before closing the can.

Dripping liquefied inert gas such as liquefied nitrogen into the can immediately before seaming can increases the Q pressure inside the can after seaming, and can save resources and cost by allowing cans with thin can bodies to be used. In addition to being able to measure the down content, it also replaces the enclosed air in the city with inert gas, which helps improve the quality of canned food.

This liquefied gas O filling situation is: ■ Target internal pressure of the can ■ Liquefied gas, for example, liquefied nitrogen (2 to L) ■ Distance between the dropping position and can θ seam ■ Can size and filling position of the contents (can size after seaming) (size of inner upper space) ■Contents υ filling conditions of hot bank or cold bank, etc.■ Varies depending on O conditions such as seaming line speed.

Original F! A moss whale first uses the O pressure of the LN2 source tank to control the internal pressure of the storage tank for dropping LN2, and also controls the opening of the needle valve in the nozzle section with a pulse motor. , developed an above-liquid gas dripping device that controls the dripping M of LN2. (% Gansho 57-
(No. 84696, No. 57-143438) That is, in a storage tank having a dripping nozzle, the liquid level in the tank is maintained constant by a float valve or the like. On the other hand, the vaporized gas accumulated in the upper part of the tank is discharged by discharging it through the pressure control valve, and the vaporized gas in the former tank, which has an internal pressure higher than the set internal pressure of the storage tank, is connected to the Q discharge pipe through the regulator to the west, When the internal pressure of the storage tank O falls below the fixed value for some reason, evaporated gas is supplied from the discharge pipe.Liquefied gas is dripped from the dripping nozzle υ21, and the needle is pulled up by the entire solenoid. This is done by opening the door. The pressure applied to the liquefied gas is kept constant by maintaining the liquid level in the storage tank and the internal pressure at all settings. Adjustment of the dropper is performed by placing a stopper during the upward stroke of the needle and controlling the opening degree of the needle valve by displacing the position of the stopper.

However, by such dripping ##cm, according to the above conditions, hand JR,! It is extremely difficult to adjust the amount of dripping by using I-techniques.In particular, the speed can be switched to two stages while the seaming machine is in operation, but if there is a DK, it is difficult to adjust the dripping amount. /min line speed to 12uc+can/min 2~
Because it switches in 3 seconds, this line 27. It is almost impossible to adjust the LN2V) rAT lid following changes in the bead, and even if it were possible, it would be difficult to reproduce. The dripping amount control f141 fr i'ii corresponds to the line speed, which requires a high and quick response. This is done by internal pressure control, making it possible to programmatically control the amount of dripping.

That is, 1 can size (202 DI can) II
Contents filling lid (250g Motomaki if kept) fti LN
Distance between the two-drop position and the pupil at the tightening position (e.g. 8υU tn/
rn) 1v BE inside the can, target value (towards Eva” 9/ctr12u
℃IVM lower tank internal pressure (e.g. "'Kq/cn?")
For each column, provisional (lkff: set, vi
Regarding the content filling temperature, 1j for 93℃, 75℃, and 20℃, respectively, the line speed and LN2 dripping mouse ■ include the relationship coefficient WA
Calculate by @ and calculation, and create a dripping amount control program according to the coefficient. The number of stocks corresponding to the temperature of the contents other than during the trial period is estimated. If any of the above On, m, and +V differs from the temporary candy, adjust the upper and lower tank internal pressure setter manually, or by Q automatic control such as interlocking with a certain Viike device, such as a can internal pressure measuring device, Assists main control.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 shows the entire system of the male side example of the dropping device of the present invention, and FIG. 2 shows the dropping vcl.

The liquefied gas is transferred from the original tank 1 to the liquid supply hose 2! 1) 7E
: I-1 The pulp is supplied to the storage tank 4 via the pulp unit 3 so as to keep the liquid level constant.

The liquefied scum in the storage tank 4 is dripped into the can 2υ by pulling up the armature 8 and the lubricant needle 9 fixed thereto. 6 limits the upward stroke, thereby regulating the distance between the valve needle 9 and the valve seat J, (J1jJJ).

The position of this aperture fine adjustment pin 6 is controlled by a step motor 5.

In the figure, 11 is a heater to prevent the V) box from adhering to the valve, 19 is a proximity sensor for detecting can 2 (JV),
13 releases vaporized gas as shielding gas, so Q~
In this dripping device, the internal pressure of the storage tank 4 is controlled as follows.

The upper space of the storage tank 4 is discharged through a vaporized gas discharge pipe 14 and a pressure regulating valve 17'. gl on the pressure setting device 21
- By setting the internal pressure of the storage tank 40 by
A current corresponding to the set value is output to the electro-pneumatic converter 22.

The gas pressure from the source tank 5 is transferred to the electro-pneumatic converter 22 through the pressure reducing valve 2.
3 at a constant pressure during operation.
Vh (At) The gas pressure is output at a variable rate.

The output gas pressure from this electro-pneumatic conversion @Kuku 22 is the storage tank 4■
Internal pressure D [supplied to valve 17 as loading air pressure. When the internal pressure of the storage tank 4 rises above the set pressure, the pressure regulating valve opens proportionally to a larger degree to maintain the internal pressure of the storage tank at the set pressure.

On the other hand, the internal pressure of the storage tank 4 is constantly monitored by the pressure detection sensor 15.
The output can be input to the point pressure 1 self-signal unit 24.

If this detected pressure is lower than the set value, the solenoid valve 16 opens by the output signal of the differential pressure transmitter 24.
The pressure reducing valve 23 is connected to the original tank l via the t+ft control valve 25.
The vaporized gas flows into the gas discharge pipe 14, increases the pressure in the tank 4, and when the pressure returns to the set pressure, the solenoid valve 16 is closed. The flow control valve 25 is used to prevent the differential pressure transmitter 24 from malfunctioning due to the application of impact pressure at the moment the solenoid valve 16 opens.

FIG. 3 shows one control circuit for controlling the above-mentioned dripping device.

This control circuit includes temperature, tank internal pressure set switches,
It consists of a control CPU, a changeover switch group, a tank internal pressure detection section, and a control section, and the above-mentioned drip amount control program is stored in the control CPU.

First, depending on the target can internal pressure, the distance between the LN2 dropping position and the seaming position, and the content filling, the corresponding tank internal pressure is selected and set using the tank pressure setting switch. The tank internal pressure is detected by the detection unit and input to the CPU, so it is compared with the above set value, and depending on the deviation, a correction signal is output to the electro-pneumatic converter or solenoid valve, thereby adjusting the tank 4 internal pressure. It is done.

Next, by setting the content temperature with the temperature setting switch, a drip lid control program with a coefficient corresponding to each silver hair is selected.

Among the switch groups, the continuous/disconnect switch is a switch for continuous dripping and intermittent dripping.The relationship coefficients between line speed and LN2 droplets are dramatically different, and by switching this switch, you can program the coefficients accordingly. is selected.0 During feeding, in the case of continuous dripping, the LN2 dripping pulp opens with the whisper open signal of the filler stopper and starts dripping.
It is programmed to close the dripping valve after T seconds with the stopper N close signal. In addition, in the case of continuous dripping, the positional relationship between the can pressure sensor 19 and the LN2 dripping nozzle is fixed, so the dripping timing according to the line speed, that is, the dripping valve is closed at T1 seconds after the can pressure signal is manually applied. ,
Pulp closure in 12 seconds is controlled computationally by the program.

The speed of the line is detected by a ζ4 timing sensor, etc.
The dripping amount corresponding to this line speed is calculated by the production of one rotation of the can or feed chain attachment.
By driving the pulse motor PMc7), the opening degree of the valve opening level adjustment bin 6 is controlled.

Among the changeover switches, manual opening and automatic opening are O in order to enable manual operation of the dripping valve when adjusting the dripping device V). In addition, the mode settings can be changed to Progera l with different coefficients depending on the can size, or when the line speed is in the low speed range and high speed range! Involved in selecting the program O according to the condition of the valley lottery, such as replacing the program in order to correspond to the possibility note J4.

A tank pressurization signal is output, and an alarm signal is output when it is indicated that pressure recovery is slow, regardless of whether the tank pressure valve 16 is open.

As mentioned above, the Q control method of the present invention prepares multiple process control programs for changing setting conditions, and replaces them to control the amount of liquefied scum dripping, so a small number of set switches are required. Accordingly, it is possible to optimally control GL and dripping M depending on the situation of each citron.

[Brief explanation of the drawing]

Figure 1 is a conceptual diagram of the liquefied gas dripping device that implements the control method of the present invention, Figure 2 is a sectional view of the dripping device, and Figure 3 is a circuit diagram of one embodiment of the control circuit. 1: Original tank 3: Float valve 4: Storage tank
6: Valve opening #adjustment bottle 7: Renoid 9: Valve needle 15: Pressure detector 16: Solenoid valve 17:
Pressure appeal 1 valve adjustment 19: Proximity sensor 21: Pressure setting device 22: Electro-pneumatic converter 24: Differential pressure oscillation surface spider 1
given name)

Claims (1)

[Claims] A storage tank for liquefied inert gas, a dripping valve for dripping the liquefied gas in the tank into a sealed @'fr11 can, and a liquefier with a pressure mochi cylinder pulp for bringing the internal pressure of the tank to a set point. In the dregs dripping device, the subordinate valve V is opened and the opening time is controlled by the line speed as an auxiliary control, and the internal pressure of the dregs storage tank is selected by a variable other than the line speed, and the line speed and dripping are controlled by a variable other than the line speed. A method for controlling the amount of liquefied gas, which is characterized by controlling the quantity and using multiple control programs of different numbers according to variables other than line speed.