JP2003137213A - Liquefied gas flow-down nozzle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure a liquefied gas flowing separately in a plurality of lines to reliably drop dispersively onto a liquid level in a container without allowing them to merge in a liquefied gas flow-down nozzle in which a quantity of a flowing liquefied gas can be steplessly or continuously fine-adjusted by making the gas flow down separately in the plurality of lines through respective grooves which are formed on an inner peripheral surface of a cylinder and have their bottoms inclined. SOLUTION: In a plurality of grooves formed on an inner peripheral surface of a cylinder 2, a depth of the grooves are made approximately the same by a predetermined height H from a lower end of each groove 22 in the vicinity of the lower end of each groove 22 having its bottom inclined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the production of a container-packaged beverage product such as a canned beverage, in which an upper opening container which has been filled with a beverage and which has not been sealed yet is continuously conveyed toward a sealing device. The present invention relates to a liquefied gas flow-down nozzle used for flowing a low temperature liquefied gas of an inert gas into a head space of a container by a predetermined amount.

[0002]

2. Description of the Related Art Non-carbonated beverages such as coffee, black tea, green tea, oolong tea, sports drinks, and fruit juices are filled into a can body having a thin wall such as a DI (squeezed ironing) can for canning. In addition, after adding a small amount of a low temperature liquefied gas of an inert gas such as liquid nitrogen or liquefied argon to the liquid surface of the head space in the can filled with the beverage (the space where there is no beverage in the upper part of the can), By sealing the can lid by tightening it around the opening of the can, the internal pressure of the can after sealing is increased to prevent deformation of the can due to external pressure, and the air in the can is replaced with an inert gas to remove residual oxygen. It has been generally practiced in the past to reduce the amount of the beverage to prevent deterioration of the beverage due to oxidation.

On the other hand, as a can lid winding device used for the production of canned goods, low speed operation and high speed operation (twice the speed of low speed operation)
In addition to the type that switches to the 2nd speed, the one that can change the speed from low speed operation to high speed operation steplessly (curve or slope) has been developed recently.
The liquefied gas flow-down device for adding liquefied gas to the head space inside the can is also stepless in the manufacturing line so that it can correspond to the conveying speed of the can on the manufacturing line that matches the operating speed of this can lid wrapping device. It has been proposed by the applicant of the present invention to make it possible to continuously and steplessly change the amount of liquefied gas flowing down per unit time by following a constant speed change, and according to Japanese Patent Laid-Open No. 10-250711. It is already known.

That is, in Japanese Laid-Open Patent Publication No. 10-250711, a liquefied gas flow nozzle composed of a cylinder and a plug is provided on the inner peripheral surface of the cylinder which is in sliding contact with the outer peripheral surface of the plug, from the upper end to the lower end of the cylinder. A plurality of groove portions for passing through are formed, and at least one or more of each groove portion has a substantially constant width from the upper end to the lower end, and the groove bottom is gradually shallowed. By inclining, the rising position of the plug with respect to the cylinder can be changed so that the amount of liquefied gas flowing through each groove (the amount of liquefied gas per unit time) can be changed continuously and steplessly. It is disclosed.

[0005]

By the way, according to the liquefied gas flow-down nozzle as described above, the liquefied gas is flowed down from a plurality of groove portions separately into a plurality of streams.
The impact of collision with the liquid surface of the beverage during the flow of the liquefied gas can be mitigated, the liquefied gas can be prevented from scattering outside the can, and a plurality of nozzles with different numbers and sizes of nozzle holes are provided. Without changing the nozzle itself and using it, just change the rising position of the plug,
The flow rate of liquefied gas can be finely adjusted steplessly or continuously, and the flow rate of liquefied gas per unit time can be continuously and continuously changed by following the stepless speed change of the canning production line. It can be changed steplessly.

[0006] However, further examination of such a liquefied gas flow-down nozzle has revealed that there are almost no problems in the production of canned beverages using ordinary cylindrical cans such as DI cans, but in recent years it has been used for various beverages. The following problems may occur during the production of canned beverages using rapidly expanding bottle-shaped cans (metal cans with integrally molded screw neck and thin body). It has been found.

That is, in the case of a bottle-type can having a screw-necked neck portion, the inner diameter of the opening is considerably smaller than that of a normal cylindrical can (in a normal can, the inner diameter of the opening is It is about 48 to 60 mm, whereas the inner diameter of the opening is about 20 to 30 mm in the bottle type can), and the liquefied gas flow-down nozzle to be used must necessarily be small, and the groove bottom The inner diameter of the cylinder including the part is 15
It is necessary to set it to mm or less (preferably 10 mm or less).

Therefore, as a liquefied gas flow-down nozzle that can be applied to bottle-shaped cans, specifically, the upper end surface is a mortar-shaped concave curved surface, and the groove portion (the groove width is about 1 mm) parallel to the axis is the inner peripheral surface. The diameter of the virtual circle connecting the groove bottoms of the respective groove portions at the upper end of the groove portion is about 9mm, and the diameter of the virtual circle connecting the groove bottoms of the respective groove portions at the lower end of the groove portion is about 7mm. In addition to creating a cylinder so that the inclination angle of the groove bottom with respect to the axis of the groove is about 3 ° and the diameter of the imaginary circle connecting the inner peripheral surface where the groove is not formed is about 5.5 mm, Has a rod-shaped (cylindrical) plug portion that slidably contacts with the inner peripheral surface of the cylinder, and above the rod-shaped plug portion is a resin-made closing portion having a convex curved surface that matches the concave curved surface of the upper end surface of the cylinder. I made a plug with.

Further, a liquefied gas flow-down device in which a liquefied gas passage is connected to the lower end of the liquefied gas storage tank, and the liquefied gas flow-down nozzle composed of the cylinder and the plug is provided at the lower end of the liquefied gas passage. By using the opening / closing valve provided in the liquefied gas supply pipe that connects the liquefied gas storage tank of the device and the liquefied gas source tank, the liquid level of the storage tank is detected and opened / closed, By maintaining the height of the liquid level in the tank substantially constant and communicating the inside of the storage tank with the outside,
While maintaining the pressure on the liquid surface in the storage tank at atmospheric pressure, each groove (8) on the inner peripheral surface of the cylinder of the liquefied gas flow-down nozzle
Liquid nitrogen is kept flowing down through the groove of the book) (per unit time), and the inner diameter of the mouth / neck opening is 20
About 491 g of a bottle-shaped can with a capacity of 500 ml in mm
After passing the liquefied gas flow nozzle under the liquefied gas flow nozzle in a state of being filled with water, add a predetermined amount of liquid nitrogen into the bottle-shaped can, seal the cap with the cap, and then touch An experiment was conducted to measure the internal pressure of a can with a can machine.

As a result, as shown in FIG. 5, the liquid nitrogen flowing down from the liquefied gas flowing nozzle is dispersed in the same number (8) of threads as the number of groove portions of the cylinder immediately below the nozzle. However, since the groove bottom of each groove of the cylinder is inclined toward the center, a plurality of (8) filamentous flows gradually approach each other in the middle, and finally one flow Therefore, the impact of liquid nitrogen falling on the liquid surface in the can increases, and the view on the liquid surface in the can increases and the liquid nitrogen scatters. It has been found that the problem that the variation in the internal pressure of each can becomes large due to the above.

The present invention is intended to solve the above problems. Specifically, a plurality of liquefied gases are passed through a groove portion formed on the inner peripheral surface of a cylinder with an inclined groove bottom. The flow rate of the liquefied gas can be finely adjusted steplessly or continuously by dividing the liquefied gas into multiple streams, and the liquefied gas that has been divided into multiple streams and flowed down It is an object of the present invention to drop onto the liquid surface in the container while being surely dispersed, without merging with each other.

[0012]

In order to solve the above-mentioned problems, the present invention comprises a cylinder whose axis is vertical and a plug which is inserted into the cylinder from above, and which slides on the outer peripheral surface of the plug. From the upper end to the lower end of the inner peripheral surface of the contacting cylinder, there is a groove for passing liquefied gas,
A plurality of cylinders are formed in parallel with each other in the axial direction of the cylinder, and at least one pair of opposing groove portions have a substantially constant width from the top to the bottom so that the depth of the groove gradually becomes shallow. The bottom of the groove is slanted, and when the plug that can move up and down relative to the cylinder reaches the bottom end position, each groove of the cylinder is closed by the plug. In the nozzle, in the vicinity of the lower end of the groove portion where the groove bottom of the cylinder is inclined, the depth of the groove is substantially the same from the lower end of the groove portion by a predetermined height.

According to the above construction, when the liquefied gas is made to flow down through the respective groove portions of the cylinder by raising the plug from the lowermost position, the raising position of the plug is changed according to the speed of the manufacturing line. Thereby, the amount of liquefied gas flowing down (the amount of liquefied gas per unit time) passing through each groove portion where the groove bottom of the cylinder is inclined can be continuously and steplessly changed.

Further, in order to change the flow rate of the liquefied gas, at least one pair of the groove portions facing each other are inclined and the groove bottom is inclined so that the depth of the groove is gradually decreased from top to bottom. On the other hand, in the vicinity of the lower ends of the grooves, the depths of the grooves are made substantially the same from the lower ends of the grooves by a predetermined height, so that as shown in FIG. The liquefied gas that has flowed down slightly toward the center along the bottom of the groove along the non-tilted groove bottom of approximately the same depth changes to a downward (vertical) flow. The liquefied gas flowing down from the lower end of the groove is
Without merging on the way, it becomes the same number of undisturbed threads as the number of grooves, and always flows down stably.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a liquefied gas flow-down nozzle of the present invention will be described below in detail with reference to the drawings. Regarding the liquefied gas flow-down nozzle of the present embodiment, FIG. 1 shows the lower end portion of the liquefied gas flow-down device in which the nozzle is arranged, and FIG. 2 shows a state in which the nozzle is opened at a desired opening degree. 3A and 3B show the structure of the cylinder that constitutes the nozzle, and FIG. 4 shows the state in which the liquefied gas flows down through the groove of the cylinder. Further, FIG. 5 shows a state in which the liquefied gas flows down through the groove of the cylinder in the liquefied gas flow-down nozzle of the comparative example.

Although the overall structure of the liquefied gas flow-down device (the structure of the other parts except the structure of the nozzle part) using the liquefied gas flow-down nozzle of the present embodiment is not shown, for example, 63-35933, Japanese Utility Model Publication No. 1-10331, Japanese Patent Publication No. 1-59170, Japanese Unexamined Patent Publication No. 10-250711, etc. The liquefied gas flowed down through a nozzle provided at the lower end of the gas flow-down device is added from above to the head space of the can that has been filled with the beverage and has not yet been sealed.

In such a liquefied gas flow-down device, a low-temperature liquefied gas (a low-temperature liquefied gas of an inert gas such as nitrogen gas or argon gas) supplied from the original tank for liquefied gas is insulated from the ambient temperature. After being stored in the storage tank surrounded by the vacuum insulation chamber, the height of the liquid surface of the liquefied gas stored in the storage tank was always kept constant, and the liquid surface was opened to the atmosphere ( On the liquid surface is almost the same as atmospheric pressure),
Due to its own weight, it is made to flow down through the liquefied gas flow-down nozzle while always being under a constant pressure.

The liquefied gas flow-down nozzle of this embodiment used in such a liquefied gas flow-down device will be described. At the lower end of the liquefied gas flow-down device, as shown in FIG. A liquefied gas passage 5 is formed so as to communicate with the bottom of the storage tank 4 in an enclosed state, and the cylinder 2 is provided at the lower end of the liquefied gas passage 5.
A nozzle 1 for flowing a liquefied gas, which is composed of a plug and a plug 3, is provided. Further, in order to prevent the water vapor from the beverage in the atmosphere and in the can from rising to the vicinity of the outlet of the nozzle 1 due to the flow of the low-temperature liquefied gas, corresponding to the nozzle 1, and to be frozen and adhered. , The defrosting cover 7 is the vacuum insulation chamber 6
Is detachably attached to an outer cylinder portion 8 surrounding the liquefied gas passage 5 as a part of the outer wall of the nitrogen gas, and the nitrogen gas dried in the gap between the defrosting cover 7 and the outer cylinder portion 8 is removed. Is introduced so as to flow out from the opening at the lower end of the anti-frost cover 7. Although not shown, a heater is attached to the anti-frost cover 7 to prevent frost from adhering to the vicinity of the opening.

In the nozzle 1 for flowing liquefied gas, the cylinder 2 is packed with a flange portion 21 formed on the outer peripheral surface near the lower end of the cylinder 2 by a cylinder cap 9 screwed onto the lower outer peripheral surface of the outer cylinder portion 8. The plug 3 is fixed to the bottom wall of the liquefied gas passage 5 in a state of being fastened together with the plug 3, and the plug 3 is attached to the lower end portion of a long rod 10 extending in the vertical direction, which itself has a generally known structure. Through the joint 11, the plug 3, which is movably connected so as to be able to swing back and forth and to the left and right and to be eccentrically slidable, and which is inserted into the cylinder 2 from above can be moved up and down by the rod 10. , Is vertically movable with respect to the fixed cylinder 2.

The plug 3 of the nozzle 1 has a cold resistance and a resistance such as a fluororesin or a polyamide resin above the cylindrical rod-shaped plug portion 31 which is in sliding contact with the cylindrical inner peripheral surface (cylinder hole) of the cylinder 2. A packing member 32 made of resin having excellent wear resistance and slipperiness is integrally attached, and as shown in FIG. 1, it is completely inserted until the lower end of the rod-shaped plug portion 31 of the plug 3 reaches the lower end of the cylinder 2. State (plug 3
Is in the lowermost position), the lower surface of the packing member 32 of the plug 3 (of the cylinder 2 of the cylinder 2 is different from the upper end surface 23 of the cylinder 2 which is formed in the concave shape of the mortar (or may be a tapered surface of the mortar). The convex shape which matches the concave shape of the upper end surface 23) is closely attached.

The cylinder 2 of the nozzle 1 is shown in FIG.
As shown in (A) and (B), a flange portion 21 is formed on the outer peripheral surface near the lower end of the cylinder 2, and the inner peripheral surface 20 of the cylinder 2 is in sliding contact with the outer peripheral surface of the rod-shaped plug portion 31 of the plug 3.
In addition, the width of the groove is almost constant from the upper end to the lower end, the depth of the groove bottom gradually decreases from top to bottom, and it becomes extremely small near the lower end. A plurality of (22 in the illustrated example) 22 are formed in a radial pattern with respect to the axis of the cylinder 2, and are parallel to the axial direction of the cylinder 2.

In the nozzle 1 for flowing down the liquefied gas composed of the cylinder 2 and the plug 3 as described above, as shown in FIG. 1, the plug 3 is completely inserted into the cylinder 2 until it reaches the lowermost position. In this state, the lower surface of the packing member 32 of the plug 3 comes into close contact with the upper end surface 23 of the cylinder 2, so that the upper end open portions of the groove portions 22 of the cylinder 2 are all blocked by the packing member 32 of the plug 3.
Since the nozzle 1 is completely closed, the liquefied gas stored in the storage tank 4 is
Does not flow down through the nozzle 1.

By raising the rod 10 by a desired amount of movement from such a state, as shown in FIG. 2, when the plug 3 is moved upward by a desired height with respect to the cylinder 2 and stopped, The packing member 32 of the plug 3 is separated upward from the upper end surface 23 of the cylinder 2,
The upper end open part of each groove part 22 of No. 2 communicates with the liquefied gas passage 5, and at the bottom position of the groove part 22 of the cylinder 2 at the lower end position of the rod-shaped plug part 31 of the stopped plug 3 (cross-sectional area of groove part). Accordingly, each groove 22 is opened downward so that the liquefied gas passes therethrough.

Therefore, the liquefied gas stored in the storage tank 4 flows from the liquefied gas passage 5 to each groove portion of the cylinder 2 at a flow rate corresponding to the cross-sectional area of each groove portion 22 of the cylinder 2 at the lower end position of the plug 3. A plurality of (eight) uniform yarns are dispersed through 22 to flow downward. Therefore, the rising position of the plug 3 with respect to the cylinder 2 is adjusted by the movement amount of the rod 10 to move downward. By changing the cross-sectional area of each groove 22 to be opened, the amount of liquefied gas flowing down through each groove 22 (nozzle 1
The opening degree) can be continuously changed steplessly.

Regarding the control of the opening of the nozzle 1 by controlling the rising position of the plug 3 as described above, a specific example of the case of applying it to an actual canning production line will be described in detail. Per unit time, and the flow rate of the liquefied gas per unit time, and the flow rate of the liquefied gas per unit time required to produce canned food at the speed of the canning production line (the internal pressure required for the canned food to be produced is The relationship with the obtained quantity) is checked in advance, and while inputting them into the computer, the speed of the canning production line is monitored and sent to the computer, and the position of the plug 3 matching the speed is calculated. When a signal for instructing the position movement of the plug 3 is sent to a servomotor (not shown) attached to the upper end of the rod 10, the canned product is produced at the speed of the line. By moving the plug 3 to a position where a required amount of liquefied gas per unit time can be obtained, the amount of liquefied gas flowing from the nozzle 1 can be adjusted to a non-step change in line speed. It can be changed in steps.

By the way, the groove bottom of each groove formed in the cylinder of the nozzle for flowing the liquefied gas gradually becomes shallower from the upper end to the lower end (in the direction toward the axis of the cylinder 2). In the case where the liquefied gas is tilted in the same manner, the liquefied gas is flown down as shown in FIG.
On the way, the filamentous flow from each groove 22 gradually approaches and eventually merges into a single flow. As a result, depending on the distance between the liquid level of the headspace in the can and the nozzle, When the liquefied gas falls on the liquid surface, the impact is large, and the view on the liquid surface becomes large, and the liquefied gas may be scattered.

In order to deal with such a problem, in the liquefied gas flow-down nozzle 1 of the present embodiment, as shown in FIG. 4, a predetermined height H from the lower end of the groove portion 22 is provided near the lower end of the groove portion 22. The depths of the grooves are made substantially the same, that is, the groove bottoms are extended from the lower ends of the groove portions 22 in a substantially vertical direction by a predetermined height H without being inclined.

According to the liquefied gas flow-down nozzle 1 of this embodiment as described above, the groove portions 22 of the cylinder 2 are simply changed by controlling the movement amount of the rod 10 and changing the rising position (fixed position) of the plug 3. The flow rate of the liquefied gas flowing down from the nozzle 1 through the nozzle 1 can be continuously changed steplessly by a small amount so as to correspond to the stepless change in the speed of the canning production line. The amount of liquefied gas required to obtain a constant can internal pressure can be added to the can regardless of the speed change of the can.

The plurality of groove portions 22 of the cylinder 2 are also provided.
The liquefied gas that has flowed through the can can be made to flow down into the lower can in the state of being dispersed in a uniform filament shape without joining in the middle, and the liquefied gas that has flowed down is the beverage liquid in the can. Since the impact at the time of colliding with the surface can be mitigated, it is possible to effectively prevent the liquefied gas from scattering outside the container due to the impact due to the collision with the liquid surface.

That is, as shown in FIG. 4, in the vicinity of the lower end of the groove portion 22, a predetermined height H (preferably 2 to 1) from the lower end is obtained.
0 mm, particularly preferably 3 to 8 mm), the depths of the grooves are made substantially the same, so that the liquefied gas that has flowed down slightly toward the center along the inclined surface of the groove bottom of the groove portion 22 is In the vicinity of the lower end (range of a predetermined height H from the lower end), the current flows along the non-inclined groove bottoms of substantially the same depth, so that the flow changes downward (vertical direction). The liquefied gas that has flowed down through the groove portion 22 does not merge into a single stream on the way, but flows down into the lower can in a state of being dispersed in a uniform filament shape. In addition, chamfering the corner of the lower end of the groove bottom at the lower end of the groove is also effective in flowing down the liquefied gas in a state of being dispersed in a uniform filament shape, and in particular, the above predetermined height H is If it is short (1 to 3 mm),
It is preferable to chamfer the corners.

Further, in this embodiment, the nozzle outlet portion 24 at the lower end surface of the cylinder 2 by the respective lower ends of the respective groove portions 22 and the portion between them is projected below the peripheral portion 25, so that liquefaction is achieved. The gas has good drainability (the liquefied gas does not flow from the lower end of each groove 22 to the peripheral portion).

Further, in this embodiment, since the rod 10 and the plug 3 are connected via the universal joint 11, the mounting position of the rod 10 and the mounting position of the cylinder 2 are slightly deviated, or the rod 10 is moved. Even if the shaft center of the rod 10 and the shaft center of the cylinder 2 do not precisely coincide with each other due to slight tilt, when the plug 3 is inserted in the cylinder 2, the rod 10 is tilted with respect to the cylinder 2. Is not affected, the plug 3 is inserted into the cylinder 2 without tilting, and as a result, the outer peripheral surface of the plug 3 (rod-shaped plug portion 31) and the inner peripheral surface of the cylinder 2 (cylinder hole) are in sliding contact with each other. The so-called galling phenomenon does not occur between the upper surface 23 of the cylinder 2 and the lower surface of the packing member 32 of the plug 3 and the tight contact between the upper surface 23 of the cylinder 2 and the lower surface of the packing member 32. Gender will not be such as becomes worse.

Further, in this embodiment, as shown in FIG. 3 (B), the upper end surface 23 of the cylinder 2 is formed into a mortar-shaped concave curved surface (or a mortar-shaped tapered surface).
As a result, when the plug 3 is inserted into the cylinder 2 from above, the rods 10 and the cylinder 2 are not precisely aligned with each other in the axial center, so that the lower end of the plug 3 (the rod-shaped plug portion 3
Even if the positional relationship between the lower end (1) and the cylinder hole of the cylinder 2 is deviated, the plug 3 can be easily inserted into the cylinder 2.

That is, the shape of the upper end surface of the cylinder 2 may be any shape including a flat surface as long as the shape of the lower surface of the packing member 32 of the plug 3 is matched with it. 2 upper end surface, such as a tapered surface or concave curved surface inclined like a mortar,
By forming the inclined surface so as to incline downward from the outer peripheral portion toward the central portion, when the plug 3 is inserted into the cylinder 2 from above, the lower end of the plug 3 (lower end of the rod-shaped plug portion 31) and the cylinder Even if the positional relationship with the second cylinder hole is deviated, the lower end of the plug 3 is forcibly guided to the central cylinder hole by the inclined surface of the upper end of the cylinder 2 simply by lowering the rod 10. ,
The plug 3 can be easily inserted into the cylinder 2.

As shown in FIG. 3B, in order to form the upper end surface 23 of the cylinder 2 into a mortar-shaped inclined surface, the upper surface 23 is formed into a concave curved surface instead of a simple tapered surface.
If the lower surface of the packing member 32 of the plug 3 is formed to have a convex curved surface so as to match the concave curved surface, the upper end surface 23 of the cylinder 2 and the packing member 32 of the plug 3 can be formed as compared with the case where it is simply a tapered surface. The contact area with the lower surface of the cylinder 2 can be increased as much as possible, and the upper end surface 23 of the cylinder 2
It is possible to improve the sealing performance when the nozzle is closed due to the close contact between the plug 3 and the packing member 32 of the plug 3.

Although one embodiment of the liquefied gas flow-down nozzle of the present invention has been described above, the present invention is not limited to the specific structure shown in the above-mentioned embodiment, and, for example, The shape of the inner peripheral surface of the cylinder (and the outer peripheral surface of the rod-shaped plug portion of the plug) is not limited to the one having the cross-sectional shape of a perfect circle as shown in the above embodiment,
As an elliptical cross-sectional shape having a pair of opposed plane walls, a plurality of groove portions may be formed in parallel on each of the plane walls from the upper end to the lower end of the cylinder. In such a case By installing a liquefied gas flow-down nozzle so that the plane wall is parallel to the can conveying direction, it is possible to collect a plurality of streams of liquefied gas to be dispersed and flow down in a narrow range. Therefore, it is suitable for flowing the liquefied gas into the container having a small opening diameter.

Further, the plurality of groove portions formed on the inner peripheral surface of the cylinder are not limited to those having the same shape in which all the groove portions have the inclined groove bottoms as shown in the above-mentioned embodiment, but a plurality of groove portions may be formed. It suffices that the groove bottoms are inclined in at least one pair of the groove portions facing each other, and the number and size of the groove portions can be appropriately changed. The smaller the number of plugs, the smaller the flow rate of the liquefied gas does not change significantly even if the position of the plug is changed.Therefore, in order to increase the range of change in the flow rate of the liquefied gas, the liquefied gas should be dispersed and flowed down. It is preferable to provide an appropriate number of groove portions on the bottom surface and to incline all (or most of) the groove bottoms.

Further, regarding the plug of the liquefied gas flow-down nozzle, in the above embodiment, the lower end of the rod for moving the plug and the plug are connected via the universal joint, but the axial center of the rod supporting the plug is used. The rod and the plug may be directly connected to each other as long as the axes of the cylinder and the axis of the cylinder can be precisely matched. Further, regarding the shape of the upper end surface of the cylinder, in the above-described embodiment, from the outer peripheral portion toward the central portion. Although the inclined surface is inclined downward (a mortar-shaped concave curved surface or a tapered surface), it is needless to say that the design can be changed as appropriate such as a flat surface or another shape.

[0039]

According to the liquefied gas flow-down nozzle of the present invention as described above, the flow-down amount of the liquefied gas per unit time can be changed steplessly by a simple structure, Since the flow rate of liquefied gas per unit time can be increased or decreased by following the stepless speed change of the line, no matter how the production line speed changes, the desired amount of liquefied gas can always be stored in the container. The liquefied gas that is dispersed from the nozzle and flows down can be added downward to the liquefied gas that has been dispersed in a uniform filamentous state without flowing down, It is possible to prevent the liquefied gas from scattering due to the collision with the liquid surface in the container.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a lower end portion of a liquefied gas flow-down device provided with a liquefied gas flow-down nozzle according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing a state where the liquefied gas flow-down nozzle shown in FIG. 1 is opened at a desired opening.

3A is a top view showing the structure of the cylinder of the liquefied gas flow-down nozzle shown in FIG. 1, and FIG.
The longitudinal cross-sectional view along the B line.

FIG. 4 is an explanatory longitudinal cross-sectional view showing a state in which the liquefied gas flows down through the groove of the cylinder in the cylinder of the liquefied gas flow-down nozzle shown in FIG.

FIG. 5 is a vertical cross-sectional explanatory view showing a state in which a liquefied gas flows down through a groove portion of a cylinder in a comparative example of a liquefied gas flow-down nozzle.

[Explanation of symbols]

1 (for liquefied gas flow) nozzle 2 cylinders 3 plugs 22 Groove 24 Nozzle outlet H The predetermined height from the bottom of the groove

Claims (3)

[Claims] 1. A groove portion for passing a liquefied gas from an upper end to a lower end of an inner peripheral surface of a cylinder which has a vertical axis and a plug which is inserted into the cylinder from above and slidably contacts the outer peripheral surface of the plug. Is formed in parallel with the axial direction of the cylinder, and at least a pair of opposing groove portions have a substantially constant width from the top to the bottom, and the depth of the groove gradually decreases. The liquefied gas is designed so that the groove bottom is inclined so that when the plug that can move up and down relatively to the cylinder reaches the lowest position, each groove of the cylinder is blocked by the plug. In the flow-down nozzle, near the lower end of the groove portion where the groove bottom of the cylinder is inclined, the depth of the groove is approximately the same as the depth of the groove from the lower end of the groove portion. Le. 2. The predetermined height of a portion where the depth of the groove is substantially the same from the lower end of the groove portion where the groove bottom is inclined is 2 to 10 mm.
The liquefied gas flow-down nozzle according to claim 1, wherein 3. The nozzle outlet portion at the lower end surface of the cylinder, which is formed by the respective lower ends of the respective groove portions and the portion between them, projects downward from the peripheral portion thereof. Liquefied gas flow nozzle.