JPS6335933Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a device for quantitatively flowing low-temperature liquefied gas, and more specifically, to a nozzle chip equipped with a discharge hole for limiting the flow rate of low-temperature liquefied gas. The present invention relates to a quantitative flow device for low-temperature liquefied gas that can be replaced (or removed and installed) easily and quickly, and also requires less time to restart the device.

[Technical background of the invention, prior art and its problems]

In recent years, when non-carbonated drinks such as tomato juice, vegetable juice, fruit drinks, mineral water, etc., non-sparkling alcoholic drinks such as sake and wine, and general foods such as fruits pickled in syrup are filled into thin-walled cans. In order to prevent dents from forming in the can body, a predetermined amount of low-temperature liquefied gas such as liquid nitrogen is added to the can after filling with the contents and before sealing. Positive pressure inside the can (greater than atmospheric pressure)
Many proposals have also been made regarding quantitative addition methods and devices for low-temperature liquefied gas (for example, Japanese Patent Publication No. 1983-
No. 33439, JP-A-57-86699, JP-A-57-114095
issue).

The present applicant has already proposed many research results regarding this, and many of them have been put into practical use (for example, JP-A-58-184395, JP-A-58-184396,
No. 58-183418, No. 58-183419, No. 58-193222
No., No. 58-161298, No. 58-161299, No. 58
−161300).

An example of a conventional quantitative flow device for low-temperature liquefied gas is
This will be explained with reference to FIG. 1, which is a partially cutaway front view of the same (main parts are partially omitted), and FIG. 2, which is an enlarged view of the main parts of FIG. 1 is a low-temperature liquefied gas storage tank with a double-walled insulation structure; 2 is a storage tank 1
3 is an opening formed at the bottom of the pressure buffer container 2, and 4 is a lid that closes the upper opening of the storage tank 1.

5 is a supply pipe for supplying low-temperature liquefied gas into the pressure buffer container 2; 6 is a solenoid valve attached to the supply pipe 5 for supplying or stopping the supply of low-temperature liquefied gas; and 7 is a supply pipe for supplying low-temperature liquefied gas into the pressure buffer container 2; It is a nozzle chip that has a discharge hole 8 in its center for allowing the low-temperature liquefied gas formed at the bottom to flow down in the form of a thread, and has an inclined surface that becomes a valve seat 9 around the center. Incidentally, this discharge hole 8 serves to control the flow rate of the low-temperature liquefied gas.

Reference numeral 10 denotes a valve body for flowing down or stopping the flow of low temperature liquefied gas from the discharge hole 8 in cooperation with the valve seat 9 of the nozzle chip 7; 11 is a piston rod connected to the valve body 10; It is an air cylinder that moves up and down.

Note that the valve body 10 is raised when the low-temperature liquefied gas is flowing down.

13 and 13' are vaporized gas discharge pipes, 14 is a liquid level control sensor for detecting the liquid level of low-temperature liquefied gas in the storage tank 1 and controlling the opening and closing of the electromagnetic valve 6, and 15 is a liquid level control sensor in the pressure buffer container 2. This is a filter (gas-liquid separator) attached to the tip of the low-temperature liquefied gas supply pipe 5.

16 is an inner cylindrical part for an opening provided at the lower part of the inner wall of the storage tank 1, and 17 is an outer cylindrical part for an opening provided at the lower part of the outer wall of the storage tank 1. The inner cylindrical part 16 and the outer cylindrical part 17 are It is sealed at the lower end by a closure 18.

In addition, the inner wall and outer wall of the storage tank 1 and the inner cylinder part 16
The space 19 between the storage tank 1 and the outer cylindrical portion 17 is evacuated to increase the heat insulation effect of the storage tank 1.

20 is a nozzle chip holder having a circular opening in the center and a recess large enough to accommodate the nozzle chip 7 on the lower surface side around the opening, and 21 is a nozzle chip holder for holding the nozzle chip 7; The nozzle tip 7, the nozzle tip holder 20, and the nozzle tip holder 21 constitute a nozzle part 22.

Nozzle tip holder 20 and nozzle tip presser 2
1 means that the nozzle tip 7 is removably fixed to the lower end of the storage tank 1 by pinching the outer circumference of the nozzle tip 7.

Threads are cut into the inner circumferential surface of the lower portion of the sealing member 18 and the outer circumferential surface of the upper portion of the nozzle tip holder 20, respectively, and the two are threadedly engaged (locked).
The inner circumferential surface of the lower part of the nozzle tip holder 20 and the outer circumferential surface of the nozzle tip holder 21 are each threaded, and both are engaged (locked) with screws.

In addition, 23 is a sealing tool 18 and a nozzle tip holder 2.
0 and between the nozzle tip holder 20 and the nozzle tip presser 21.

24 has an opening 31 in the center of the lower wall 30, surrounds the outer periphery of the side and lower surfaces of the nozzle part 22, and connects the outer cylinder with three bolts 25 (only one is shown in the figure). The outer wall of the vaporized gas introduction chamber is fixed to 17, and the 26 is surrounded by the outer wall 24 of the vaporized gas introduction chamber and supplies dry vaporized gas (preferably the same gas as the low-temperature liquefied gas used) from a supply source (not shown). This is an inlet for supplying vaporized gas to the vaporized gas introduction chamber 27.

28 is a coil-shaped heater wrapped around the outer circumferential surface of the vaporized gas introduction chamber outer wall 24; 29 is a resistance temperature sensor for measuring the temperature of the lower surface of the lower wall portion 30 of the vaporized gas introduction chamber outer wall 24; 28 and the resistance temperature sensor 29 are connected to a temperature controller (not shown) to keep the temperature of the outer wall 24 of the vaporized gas introduction chamber almost constant (a temperature at which frost does not adhere to the outer wall 24 of the vaporized gas introduction chamber). .

This low-temperature liquefied gas quantitative flow device maintains the surface of the low-temperature liquefied gas in the storage tank 1 at approximately atmospheric pressure,
By keeping the liquid level of the low-temperature liquefied gas constant, which is maintained at a constant level by the liquid level control sensor 14, and the diameter and number of discharge holes 8 drilled in the nozzle tip 7, the The flow rate of low-temperature liquefied gas is kept constant.

Here, low-temperature liquefied gas is directly transferred to storage tank 1.
By opening the electromagnetic valve 6 in response to a signal from the liquid level control sensor 14 and supplying the liquid from the supply pipe 5 to the pressure buffer container 2, the liquid is allowed to flow naturally into the storage tank 1 from there. , the pressure change in the storage tank 1 due to the increase in liquid pressure due to the shock when the low temperature liquefied gas flows in and the pressure of the vaporized gas generated at that time is reduced, so the variation in the amount of low temperature liquefied gas flowing down from the discharge hole 8 is further reduced. There is.

The flow rate per hour of this low-temperature liquefied gas quantitative flow device is always almost constant, so in order to always add (fill) a constant amount of low-temperature liquefied gas into the can, it is necessary to transport the gas under the discharge hole 8 of this device. This means that it is sufficient to keep the conveyance speed of the cans constant.

In addition, in order to increase or decrease the flow rate from this low-temperature liquefied gas metering flow device, that is, the amount of low-temperature liquefied gas added into the can, either increase or decrease the liquid level height of the low-temperature liquefied gas in the storage tank 1, or / and the diameter and/or number of the discharge holes 8 of the nozzle tip 7 may be increased or decreased.

By the way, when producing a gas-filled can having a constant internal pressure by adding a predetermined amount of low-temperature liquefied gas into the can, it is often necessary to replace the nozzle tip provided with the discharge hole 8.

For example, in a can production line, when changing the size of the can into which low-temperature liquefied gas is added (changing to a can with a different internal volume), the amount of low-temperature liquefied gas to be added must be increased or decreased. The internal pressure of the manufactured canned food may become insufficient or excessive, causing inconvenience, but in order to simplify the adjustment in this case, the liquid level of the liquefied gas in the storage tank 1 is not changed, and the low-temperature liquefaction is carried out. If you want to increase the amount of gas added, the discharge hole 8 should have a large diameter or/and the discharge hole 8
It is necessary to use a nozzle chip 7 with a large number of discharge holes 8, and on the other hand, if the amount of addition is to be reduced, it is necessary to use a nozzle chip 7 with a small diameter of discharge holes 8 and/or a small number of discharge holes 8. be.

Furthermore, low-temperature liquefied gases, taking liquid nitrogen as an example, have an extremely low temperature of approximately -196°C (boiling point).
As shown in FIGS. 1 and 2, the outer wall 24 of the vaporized gas introduction chamber
(e.g. 40℃), and then heat the vaporized gas introduction chamber 2.
A low-temperature liquefaction method in which dry vaporized gas at about room temperature is introduced into 7, and the lower surface of the nozzle tip 7 is covered with the dry vaporized gas to prevent water vapor from the atmosphere and the contents of the can from freezing on the nozzle tip 7. Even with a gas metering flow device, if it is operated continuously for a long time in an atmosphere where a large amount of water vapor rises from the heated and filled contents, the vaporized gas introduction chamber 27
The flow rate of vaporized gas cannot be increased too much to avoid adverse effects on the low-temperature liquefied gas flowing down (when liquid nitrogen is flowing down 2 to 3 ml/sec,
3/min) Occasionally, the cooled water vapor begins to condense on the nozzle tip 7 and the inner surface of the outer wall 24 of the vaporized gas introduction chamber, and this ice gradually grows and pinches the discharge hole 8, and the nozzle tip 7 and vaporize. By connecting the inner surface of the outer wall 24 of the gas introduction chamber, the heat of the heater 28 on the outer wall 24 of the vaporized gas introduction chamber is conducted to the nozzle tip 7, which ultimately reduces the amount of low-temperature liquefied gas flowing down from the discharge hole 8. .

Furthermore, when a filled can that has been transported under the low-temperature liquefied gas flow down device is suddenly stopped, a portion of the liquid inside the can splashes, adheres to the nozzle tip 7, and freezes. After all, the discharge hole 8 may be pinched or blocked.

If these things happen, it becomes impossible to flow down the low temperature liquefied gas at a constant rate, so if signs of ice adhesion appear on the nozzle tip 7, immediately stop the flow of the low temperature liquefied gas and replace the nozzle tip 7. or remove and clean).

In such a case, conventionally, first, all of the low-temperature liquefied gas in the storage tank 1 is allowed to flow down, then the bolts 25 are removed to remove the vaporized gas introduction chamber outer wall 24 from the outer cylindrical portion 17, and then the nozzle tip is removed. Presser foot 2
The nozzle tip 7 was removed from the lower end of the storage tank 1 by rotating the nozzle tip 7 to disengage it from the nozzle tip holder 20.

In this method, it is necessary to discharge (flow down) all of the low-temperature liquefied gas in the storage tank before replacing it (there is a risk of frostbite for the worker if the work is carried out without discharging it). During installation, since the valve body 10 has a relatively long piston rod 11, it is difficult to align this with the valve seat 9. Therefore, not only is the replacement work itself not easy, but the entire work time is The disadvantage is that it takes a long time, and most of the low-temperature liquefied gas discharged at this time is actually thrown away, so the low-temperature liquefied gas is wasted, which ultimately increases the cost of producing canned goods. Ta.

[Purpose and structure of the invention]

The object of the present invention is to provide a quantitative flow device for low-temperature liquefied gas that eliminates the drawbacks of the conventional devices and is easier to use, and its configuration is as follows.

A storage tank for low-temperature liquefied gas formed by a heat insulating wall having an upper opening; a lid that closes the upper opening of the storage tank; a lid body that is fixed to the lower end of the storage tank and has an opening in the center; A nozzle tip holder having a recess for holding the nozzle tip (described later) on the lower surface around the periphery of the nozzle tip holder; A nozzle chip that is equipped with two or more discharge holes; has an opening in the center, is removably engaged with the nozzle chip holder, and holds the nozzle chip between it and the recess on the lower side of the nozzle chip holder. A nozzle tip holder that removably fixes the nozzle tip to the nozzle tip holder; surrounds at least a portion of the outer periphery and lower surface of the nozzle tip holder, the nozzle tip, and the nozzle tip holder, and a low-temperature liquefied gas is supplied to the center of the lower wall. an outer wall of the vaporized gas introduction chamber having an opening through which the vaporized gas can pass; a valve mechanism including a valve body and a valve seat for controlling the flow down or stopping of the low-temperature liquefied gas from the discharge hole of the nozzle chip; the lid body; a low-temperature liquefied gas supply pipe and a liquid level control sensor passing through the piston rod, and a piston rod connected to the valve body at its lower end; a vaporized gas discharge pipe provided in the lid body; and a liquid level control sensor for the low-temperature liquefied gas. In the low-temperature liquefied gas quantitative flow device equipped with an on-off valve that opens and closes the low-temperature liquefied gas supply pipe in response to a signal from the A quantitative flow device for low-temperature liquefied gas, characterized in that:

[Effect]

In the present invention, the lower side of the nozzle tip holder is fixed to the lower end of the storage tank for low-temperature liquefied gas, has an opening in the center, and has a recess for holding the nozzle tip on the lower side around the opening. One or more discharge holes are provided between the recess and a nozzle tip holder that has an opening in the center and is removably engaged with the nozzle tip holder,
By clamping the nozzle chip, which is at least partially accommodated in the recess of the nozzle chip holder, the nozzle chip is removably fixed to the lower end of the storage tank, and also cooperates with the valve body fixed to the lower end of the piston rod to maintain low temperature. A valve seat for stopping or stopping the flow of liquefied gas is provided on the upper surface side around the opening of the nozzle holder, so when removing the nozzle tip, first lower the piston rod and place the valve body on the valve seat. When the nozzle tip is seated and the flow of low-temperature liquefied gas from the discharge hole is stopped, the outer wall of the vaporized gas introduction chamber is removed, and the nozzle tip holder is disengaged from the nozzle tip holder, the nozzle tip is removed from the nozzle tip holder. They can be removed together.

On the other hand, when installing a nozzle chip, first accommodate the nozzle chip in the recess of the nozzle chip holder, then engage the nozzle chip holder with the nozzle chip holder while supporting the nozzle chip with the nozzle chip holder, and then clamp the nozzle chip between them. , it is sufficient to simply fix the outer wall of the vaporized gas introduction room.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 3 is an enlarged view of the main parts of the low-temperature liquefied gas quantitative flow device of the present invention.

The low-temperature liquefied gas quantitative flow device of the present invention is the same as the conventional device except for the main parts, so these parts will be explained using FIG. 1.

Also, parts with the same numbers as those in FIGS. 1 and 2 have the same structure and function as those described in the explanation of FIGS. 1 and 2.

Here, there are a storage tank 1 for low-temperature liquefied gas, a pressure buffer container 2, an opening 3 for the pressure buffer container 2, a cover 4 for the upper opening of the storage tank 1, a supply pipe 5 for low-temperature liquefied gas, an electromagnetic valve 6 attached to the supply pipe 5, a discharge hole 8 for restricting the amount of low-temperature liquefied gas flowing down, and an air cylinder 1 for moving the piston rod 1 up and down.
2, vaporized gas exhaust pipes 13, 13, low-temperature liquefied gas liquid level control sensor 14, filter 15 attached to the tip of supply pipe 5, inner cylinder portion 16 for an opening provided at the lower part of the inner wall of storage tank 1, outer cylinder portion 17 for an opening provided at the lower part of the outer wall of storage tank 1, space 19 between the inner and outer walls of storage tank 1 and between inner cylinder portion 16 and outer cylinder portion 17, outer wall 24 of the vaporized gas introduction chamber, bolt 25, vaporized gas supply inlet 26, vaporized gas introduction chamber 27, coil-shaped heater 28, and temperature sensor 29 are the same as those in Figures 1 and 2.

The major difference from conventional devices is that a nozzle tip 37 equipped with a discharge hole 8 for restricting the amount of low-temperature liquefied gas flowing down cooperates with a valve body 40 to allow the low-temperature liquefied gas to pass through the discharge hole 8. On the other hand, the nozzle tip holder 50, which has a recess on the lower side for holding the nozzle tip 37, has a valve seat 39 around the opening on the upper side. That is what we are doing.

The valve body 40 of this embodiment has a lower end shaped like an inverted truncated cone so that it can be easily inserted into the inverted conical opening of the nozzle tip holder 50 that forms the valve seat 39.
It is also connected to the piston rod 11 at the upper end.

The sealing tool 38 that seals the lower ends of the inner cylinder part 16 and the outer cylinder part 17 and the nozzle tip holder 50 are as follows:
It is welded and joined, and the nozzle tip holder 51
The nozzle tip holder 50 has a thread cut on the inner peripheral surface of the upper part and a thread cut on the outer peripheral surface.
By screwing into the nozzle tip 37
is removably fixed to the lower end of the storage tank 1.

Therefore, when replacing the nozzle tip 37, the nozzle tip 37 can be removed by turning the nozzle tip holder 51 to release the screw engagement between the nozzle tip holder 50 and the nozzle tip holder 51.

Note that 22' is a seal ring made of a heat insulating material installed between the nozzle tip 37 and the nozzle tip holder 51 in order to maintain the sealing properties between the two.

By using a material with good heat insulation properties for this seal ring 22', it is possible to considerably prevent heat from entering from the nozzle tip holder 51 to the nozzle tip 37.

Further, 64 is a storage tank in order to prevent ice from adhering to the bottom plate of the storage tank 1 near the upper end of the outer wall 24 of the vaporized gas introduction chamber due to cold heat conduction from the nozzle tip 37, the nozzle tip holder 50, the nozzle tip presser 51, etc. This is an anti-icing plate made of a material with excellent heat insulation properties such as fluororesin that is attached to the bottom plate of the tank 1.

As described above, the low-temperature liquefied gas quantitative flow device of the present invention has the nozzle tip 37 equipped with the discharge hole 8 for limiting the flow rate of the low-temperature liquefied gas, and A valve seat 39 that cooperates with the valve body 40 to stop the valve body 40 is separate and separable, and the valve seat 39 is provided around an opening on the upper surface side of a nozzle tip holder 50 provided above the nozzle tip 37. Therefore, nozzle tip 37
, first replace the valve body 40 with the valve seat 39.
to stop the flow of low-temperature liquefied gas from the discharge hole 8. Then, after loosening the bolt 25, remove the vaporized gas introduction chamber outer wall 24 from the outer cylinder part 17, and then turn the nozzle tip holder 51. When the screw engagement between the nozzle tip holder 51 and the nozzle tip holder 50 is released, the nozzle tip 37 is removed together with the nozzle tip holder 51.

To attach the nozzle tip 37, this operation can be reversed.

When replacing this nozzle tip,
Unlike conventional equipment, there is no need to discharge the low-temperature liquefied gas in the storage tank, so not only is the low-temperature liquefied gas not wasted, but there is also no waiting time until the exhaust is finished, and there is no need to use a relatively long piston rod. 11, it is not necessary to align the valve body 40 and the valve seat 39, which is relatively difficult and time-consuming, so the overall working time is short and the work is easy. . Moreover, during this work, the inside of the storage tank 1 and the nozzle tip holder 50 continue to be cooled by the low-temperature liquefied gas in the storage tank, so after the replacement work is completed, the nozzle tip 37 and the nozzle tip holder 50 are
There is an advantage that it takes a short time for the low temperature liquefied gas to cool down to approximately the same temperature as the low temperature liquefied gas, and therefore the waiting time until the constant flow of the low temperature liquefied gas is restarted is short. In order to speed up the time from when the nozzle tip 37 is attached to when the fixed amount flow resumes, a part of the valve body 40 and the piston rod 11 is made hollow, and low-temperature liquefied gas is filled therein to cool the nozzle tip 37 with the heat radiated. You can also do it.
Further, the nozzle tip 37 used here is preferably made of brass (BsBF) from the viewpoint of low temperature resistance and workability, and the thickness of the portion where the discharge hole 8 is formed needs to be 5 mm or more.

If the thickness is less than 5 mm, the flow of the low-temperature liquefied gas will be unstable and will not flow straight down, making it difficult to add it quantitatively into the can (an experiment was conducted using liquid nitrogen).

The thickness of the valve seat 39 portion of the nozzle tip holder 50 (the vertical length of the portion in contact with the nozzle tip 37 in Fig. 4) is less than 3 mm in the case of stainless steel (SUS304), and less than 3 mm in the case of brass (BsBF). )
In this case, it has been found that it is necessary to set the diameter to less than 5 mm in order for the liquid nitrogen to flow out from the discharge hole 8 in a stable state.

If the thickness of the valve seat 39 portion is greater than the above value, liquid nitrogen will not flow down from the discharge hole 8 when the valve is opened, and nitrogen gas will come out, making the flow condition unstable when the flow starts. occurs.

In the above embodiment, the engagement (locking) between the nozzle tip holder and the nozzle tip holder is screwed, but the invention is not limited to this. On the other hand, on a part of the inner circumference of the nozzle tip holder, one or more protrusions of a size that can be inserted into the grooves are provided (if there are two or more protrusions, the distance between the grooves is the same),
The two can also be engaged (locked) by rotating the nozzle tip holder, first upwards and finally laterally. (Of course, it may also be provided on the outer peripheral surface of the tool.)

Although the outer circumferential shape of the nozzle tip was not mentioned in the above embodiment, the outer circumferential shape of the nozzle tip is rectangular, oval, or shaped like a track on an athletics field, and the lower side of the nozzle tip holder that holds the nozzle tip is If the inner periphery of the recess is similar to the outer periphery of the nozzle tip and slightly larger, then when the nozzle tip has two or more discharge holes, alignment of the rows of the discharge holes will be easier ( As a result of research by the present inventors, it has been found that by arranging the rows of discharge holes approximately parallel to the traveling direction of the can, gas-filled cans with less variation in can internal pressure can be obtained. -183419), it has the advantage that the nozzle tip replacement work becomes easier.

The embodiment shown in Fig. 3 is a type in which the liquid level in the storage tank for low-temperature liquefied gas is maintained at approximately atmospheric pressure. It can also be applied to a type of low-temperature liquefied gas quantitative flow device that maintains the upper pressure at a constant pressure higher than atmospheric pressure. In addition, although the device of the present invention was explained as a device for adding to cans, it can of course also be used as a device for adding a fixed amount of low-temperature liquefied gas to glass bottles, plastic containers, composite containers, etc. be.

[Effect of idea]

When replacing a nozzle chip equipped with a discharge hole to limit the flow of low-temperature liquefied gas, the device of the present invention is designed to seat a valve body on a valve seat provided on the upper surface side around the opening of a nozzle chip holder. After that, you can immediately start removing the outer wall of the vaporized gas introduction chamber, the nozzle tip holder, and the nozzle tip, compared to conventional equipment that requires removing all the low-temperature liquefied gas in the storage tank before starting removal work. Removal work can be done in a short time,
In addition, low-temperature liquefied gas is not wasted, and since the nozzle tip holder with the valve seat is not removed during removal work, the valve body and valve seat can be easily attached to each other during the nozzle chip installation work, which was done with conventional equipment. Positioning work is no longer required, making installation work easier and faster.Furthermore,
During these operations, low-temperature liquefied gas is stored in the storage tank, and the storage tank and nozzle tip holder are kept at a low temperature. Compared to conventional equipment, in which the nozzle tip is replaced after the nozzle tip has been completely discharged, the time required for restarting the device (in the present device, the time required for the nozzle tip and the nozzle tip holder to cool down to approximately the same temperature as the low-temperature liquefied gas; With the device, the low-temperature liquefied gas is supplied to a predetermined height in the storage tank, and the time required for the storage tank, nozzle tip holder, nozzle tip, and nozzle tip presser to be cooled to almost the same temperature as the low-temperature liquefied gas is short. This device has the great practical advantage of being easy to use.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway front view of a conventional low-temperature liquefied gas quantitative flow device; Fig. 2 is an enlarged view of the main part of the device shown in Fig. 1; FIG. 2 is an enlarged view of the main parts of the device. 1... Storage tank for low-temperature liquefied gas, 4... Lid, 5... Supply pipe, 6... Solenoid valve, 7, 37...
Nozzle chip, 8... Discharge hole, 9, 39... Valve seat, 10, 40... Valve body, 13, 13'... Vaporized gas discharge pipe, 14... Liquid level control sensor, 20,
50... Nozzle tip holder, 21, 51... Nozzle tip holder, 24... Vaporized gas introduction chamber outer wall.

Claims (1)

[Scope of Claim for Utility Model Registration] A low-temperature liquefied gas storage tank formed by a heat insulating wall having an upper opening, a lid that closes the upper opening of the storage tank, and a lid fixed to the lower end of the storage tank, A nozzle tip holder is provided with an opening in the center and a recess for holding the nozzle tip (described later) on the lower side around the opening, and at least a portion of the nozzle tip holder is accommodated in the recess on the lower side of the nozzle tip holder. A nozzle tip is provided with one or more discharge holes for restricting the amount of gas flowing down, and has an opening in the center portion, is removably engaged with the nozzle tip holder, and is attached to the lower surface of the nozzle tip holder. a nozzle chip holder that clamps the nozzle chip between the concave portion and removably fixes the nozzle chip to the nozzle chip holder; and a nozzle chip holder that surrounds at least a portion of the outer periphery and lower surface of the nozzle chip holder, the nozzle tip, and the nozzle tip holder. and an outer wall of the vaporized gas introduction chamber having an opening in the center of the lower wall portion through which the low temperature liquefied gas can pass; a valve body for controlling the flow down or stop of the flow of the low temperature liquefied gas from the discharge hole of the nozzle tip a valve mechanism comprising a valve seat; a low-temperature liquefied gas supply pipe and a liquid level control sensor passing through the lid; a piston rod connected to the valve at its lower end; and a vaporizer provided in the lid. In the low-temperature liquefied gas quantitative flow device comprising a gas discharge pipe and an on-off valve that opens and closes the low-temperature liquefied gas supply pipe based on a signal from the low-temperature liquefied gas liquid level control sensor, the valve mechanism comprises: A quantitative flow device for low-temperature liquefied gas, characterized in that a valve seat is provided around an opening on the upper surface side of the nozzle tip holder.