Double-layer keg

Abstract

A double-layer keg comprises an outer barrel and an inner barrel made of plastic disposed in the outer barrel. A bottom of the outer barrel is fixed with a base, and a lower portion of the outer barrel has a brace for supporting a bottom periphery of the inner barrel. A spear structure is installed at a barrel opening of the inner barrel, and an upper portion of the inner barrel has a shoulder and a neck disposed around the barrel opening. An inner surface of an upper portion of the outer barrel is pressed against an outer surface of the shoulder and/or the neck of the inner barrel. An expansion space, provided for the bottom of the inner barrel to expand downward, is disposed between a portion of the bottom of the inner barrel located at an inner side of the brace and the base.

Claims

1. A double-layer keg, comprising: a rigid outer barrel, the outer barrel having an outer barrel upper portion, an outer barrel lower portion, and an outer barrel bottom; a brace on an inner surface of the outer barrel lower portion, and the outer barrel bottom being fixed with a base; an inner barrel made of plastic disposed in the outer barrel, the inner barrel having an inner barrel opening at an inner barrel upper portion, the inner barrel having an inner barrel bottom; a shoulder and a neck of the inner barrel disposed around the inner barrel opening; and a spear structure being installed at the inner barrel opening; wherein an inner surface of the outer barrel upper portion is pressed against an outer surface of the shoulder and/or the neck of the inner barrel; wherein a bottom periphery of the inner barrel is supported by the brace of the outer barrel; wherein an expansion space is disposed between the base and a middle portion of the inner barrel bottom, the middle portion located at an inner side of the brace, and the expansion space is capable of allowing the inner barrel bottom to expand downward; wherein the base has an annular slot in a circumferential direction, a lower end edge of the outer barrel is inserted downwardly in the slot: and wherein the expansion space is capable of being adjusted by changing a depth of the outer barrel in the slot through a downward expansion of the inner barrel.

2. The double-layer keg as claimed in claim 1, wherein the outer surface of the shoulder is a flat surface, a tapered surface, or a first arcuate surface, and the inner surface of the outer barrel and the outer surface of the shoulder are fitted and pressed against each other.

3. The double-layer keg as claimed in claim 2, wherein both the outer barrel and the inner barrel each has a straight cylindrical trunk, and an inner surface of the trunk of the outer barrel and an outer surface of the trunk of the inner barrel are fitted with each other.

4. The double-layer keg as claimed in claim 3, wherein an opening of the slot faces upward, and an outer surface of the lower end of the outer barrel is tightly fitted with a slot wall of the slot of the base.

5. The double-layer keg as claimed in claim 2, wherein both the outer barrel and the inner barrel each has a straight cylindrical trunk, and a gap with a width of less than 5 mm is disposed between an inner surface of the trunk of the outer barrel and an outer surface of the trunk of the inner barrel.

6. The double-layer keg as claimed in claim 5, wherein an opening of the slot faces upward, and an outer surface of the lower end of the outer barrel is tightly fitted with a slot wall of the slot of the base.

7. The double-layer keg as claimed in claim 2, wherein the brace is formed by a radial contraction of the outer barrel lower portion, the brace is in an annular shape, the brace has an upwardly inclined abutment and a downwardly inclined brace surface, and the abutment and the bottom periphery of the inner barrel are abutted against each other.

8. The double-layer keg as claimed in claim 7, wherein the outer surface of the trunk of the inner barrel and an outer surface of the inner barrel bottom are joined by a second arcuate surface, and the inner barrel abuts against the abutment of the brace through the second arcuate surface.

9. The double-layer keg as claimed in claim 8, wherein the inner barrel bottom is in an arcuate shape, and a middle portion of the inner barrel bottom is lower than the brace.

10. The double-layer keg as claimed in claim 2, wherein an opening of the slot faces upward, and an outer surface of the lower end of the outer barrel is tightly fitted with a slot wall of the slot of the base.

11. The double-layer keg as claimed in claim 1, wherein the brace is formed by a radial contraction of the outer barrel lower portion, the brace is in an annular shape, the brace has an upwardly inclined abutment and a downwardly inclined brace surface, and the abutment and the bottom periphery of the inner barrel are abutted against each other.

12. The double-layer keg as claimed in claim 11, wherein the outer surface of the trunk of the inner barrel and an outer surface of the inner barrel bottom are joined by a second arcuate surface, and the inner barrel abuts against the abutment of the brace through the second arcuate surface.

13. The double-layer keg as claimed in claim 12, wherein the inner barrel bottom is in an arcuate shape, and a middle portion of the inner barrel bottom is lower than the brace.

14. The double-layer keg as claimed in claim 1, wherein both the outer barrel and the inner barrel each has a straight cylindrical trunk, and an inner surface of the trunk of the outer barrel and an outer surface of the trunk of the inner barrel are fitted with each other.

15. The double-layer keg as claimed in claim 1, wherein both the outer barrel and the inner barrel each has a straight cylindrical trunk, and a gap with a width of less than 5 mm is disposed between an inner surface of the trunk of the outer barrel and an outer surface of the trunk of the inner barrel.

16. The double-layer keg as claimed in claim 1, wherein an opening of the slot faces upward, and an outer surface of the lower end of the outer barrel is tightly fitted with a slot wall of the slot of the base.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a cross-sectional view of a first embodiment of a double-layer keg;

(2) FIG. 2 is a cross-sectional view of a bottom of one embodiment of an inner barrel in the double-layer keg when the bottom is expanded and deformed downwardly;

(3) FIG. 3 is a cross-sectional view of a second embodiment of the double-layer keg;

(4) FIG. 4 is a cross-sectional partial view of a third embodiment of the double-layer keg;

(5) FIG. 5 is a cross-sectional partial view of a fourth embodiment of the double-layer keg;

(6) FIG. 6 is a cross-sectional partial view of a fifth embodiment of the double-layer keg; and

(7) FIG. 7 is a cross-sectional partial view of a sixth embodiment of the double-layer keg.

DETAILED DESCRIPTION OF THE INVENTION

(8) The technical solutions of the present invention are further described below with reference to the specific embodiments of the present invention in conjunction with the accompanied drawings, but the present invention is not limited to these embodiments.

Embodiment 1

(9) As shown in FIG. 1 and FIG. 2, one embodiment of a double-layer keg comprises an outer barrel 1 and an inner barrel 2, both of which are made of PET material, the inner barrel 2 is located inside the outer barrel 1, the outer barrel 1 is some rigidity for supporting the inner barrel 2. a lower end of the outer barrel 1 is penetrated, and a base 3 is fixed at a bottom of the outer barrel 1. The inner barrel 2 comprises a neck 22, a shoulder 21 and a trunk, the neck 22 is in a straight cylindrical shape, and an upper end port of the neck 22 is a barrel opening. A spear structure 4 is installed at the barrel opening of the inner barrel 2 for connecting liquor dispensing devices such as a dispenser. The shoulder 21 is disposed around the barrel opening, and an outer surface thereof is a tapered surface. Of course, the outer surface of the shoulder 21 can also be an annular flat surface, or a first arcuate surface. Corners between the shoulder 21 and the neck 22 as well as between the shoulder 21 and the trunk are arcuately designed, and there can be a gap between the outer surface of the shoulder 21 at the corner positions and an inner surface of the outer barrel 1 at the corner positions. Because the corner design has a higher strength, it does not exhibit expansion and deformation under the effect of internal pressure. Of course, the outer surface of the inner barrel 2 at the corner positions can be fitted to the inner surface of the outer barrel 1 at the corner positions, and the trunk of the inner barrel 2 is also in a straight cylindrical shape, and a height thereof is 1.66 times or more of its diameter. An inner surface of the trunk of the outer barrel 1 and an outer surface of the trunk of the inner barrel 2 are fitted with each other. An inner surface of an upper portion of the outer barrel 1 is fitted and pressed against the outer surface of the shoulder 21 and an outer surface of the neck 22. A lower portion of the outer barrel 1 has a brace 11, and a bottom periphery of the inner barrel 2 abuts against the brace 11, that is, the outer barrel 1 supports the inner barrel 2 through the brace 11. An expansion space 5 is disposed between a portion of the bottom of the inner barrel 2 located at an inner side of the brace 11 and the base 3, and the expansion space 5 is capable of allowing the bottom of the inner barrel 2 to expand downward.

(10) One embodiment of the brace 11 is formed by a radial contraction of the lower portion of the outer barrel 1, the brace 11 is in an annular shape, and the brace 11 has an upwardly inclined abutment 111 and a downwardly inclined brace surface 112. The outer surface of the trunk of the inner barrel 2 and an outer surface of the bottom of the inner barrel 2 are joined by a second arcuate surface, and the inner barrel 2 abuts against the abutment 111 of the brace 11 through the second arcuate surface. When the trunk of the inner barrel 2 expands and deforms downward, the second arcuate surface is more conducive for sliding relative to the abutment 111, so that the bottom of the inner barrel 2 expands and deforms downward. The bottom of the inner barrel 2 is in an arcuate shape, and a middle portion of the bottom of the inner barrel 2 is lower than the brace 11. The base 3 has an annular slot 31 in a circumferential direction, an opening of the slot 31 faces upward, a lower end edge of the outer barrel 1 is inserted downwardly in the slot 31, and an outer surface of the lower end of the outer barrel 1 is tightly fitted with a slot wall of the slot 31 of the base 3. If the expansion space 5 is insufficient and causes the trunk of the inner barrel 2 to expand and deform and abut against the base 3, since the outer barrel 1 is inserted downwardly and connected to the base 3 by tight fitting in place, thus the outer barrel 1 can displace upward loosely relative to the base 3, thereby the expansion space 5 becomes larger, so that the inner barrel 2 expands fully to eliminate stress concentration.

Embodiment 2

(11) The structure of the double-layer keg is basically the same as that of the first embodiment. The differences lie in, as shown in FIG. 3, a gap with a width of less than 5 mm is disposed between the inner surface of the trunk of the outer barrel 1 and the outer surface of the trunk of the inner barrel 2. The gap is used for a radial expansion of the inner barrel 2, so that the inner barrel 2 is fully expanded and uniformly contacted with the inner surface of the outer barrel 1, thereby avoiding local stress concentration and burst of the inner barrel 2 and results in bursting.

Embodiment 3

(12) The structure of the double-layer keg is basically the same as that of the first embodiment. The differences lie in, as shown in FIG. 4, the inner surface of the outer barrel 1 is simultaneously pressed against the outer surfaces of the shoulder 21 and the neck 22 of the inner barrel 2. Wherein, at the position of the shoulder 21, the inner surface of the outer barrel 1 is pressed against an arcuate and bent portion at an outer periphery of the shoulder 21 of the inner barrel 2, and there is still a certain gap above other positions of the shoulder 21 of the inner barrel 2, at this time, the outer barrel 1 can limit a position of the inner barrel 2 by pressing against the neck 22 and the arcuate and bent portion at the outer periphery of the shoulder 21 of the inner barrel 2, thereby preventing the inner barrel 2 from expanding and deforming upward.

Embodiment 4

(13) The structure of the double-layer keg is basically the same as that of the first embodiment. The differences lie in, as shown in FIG. 5, the inner surface of the outer barrel 1 is simultaneously pressed against the outer surfaces of the shoulder 21 and the neck 22 of the inner barrel 2. Wherein, at the position of the shoulder 21, the inner surface of the outer barrel 1 is pressed against an arcuate and bent portion at an inner periphery of the shoulder 21 of the inner barrel 2, and there is still a certain gap above other positions of the shoulder 21 of the inner barrel 2, at this time, the outer barrel 1 can limit a position of the inner barrel 2 by pressing against the neck 22 and the arcuate and bent portion at the inner periphery of the shoulder 21 of the inner barrel 2, thereby preventing the inner barrel 2 from expanding and deforming upward.

Embodiment 5

(14) The structure of the double-layer keg is basically the same as that of the first embodiment. The differences lie in, as shown in FIG. 6, the inner surface of the outer barrel 1 is only pressed against the outer surface of the shoulder 21 of the inner barrel 2, and there is a certain gap between the outer surface of the neck 22 of the inner barrel 2 and the inner surface of the outer barrel 1. At this time, the outer barrel 1 can limit a position of the inner barrel 2 by pressing against the shoulder 21 of the inner barrel 2, thereby preventing the inner barrel 2 from expanding and deforming upward.

Embodiment 6

(15) The structure of the double-layer keg is basically the same as that of the first embodiment. The differences lie in, as shown in FIG. 7, the inner surface of the outer barrel 1 is only pressed against the outer surface of the neck 22 of the inner barrel 2, and there is a certain gap between the outer surface of the shoulder 21 of the inner barrel 2 and the inner surface of the outer barrel 1. At this time, an outer diameter of an arcuate and bent portion at the lower end of the neck 22 of the inner barrel 2 gradually becomes larger, thus can also limit a position of the inner barrel 2 to prevent the inner barrel 2 from expanding and deforming upward.

(16) The specific embodiments described herein are merely illustrative of the spirit of the present invention. Technical personnel skilled in the art to which the present invention pertains can make various modifications or additions to the specific embodiments described or replace them in a similar manner, without departing from the spirit of the present invention or beyond the scope defined by the appended claims.

(17) Although the terms outer barrel 1, brace 11, abutment 111, and the like are used more frequently herein, the possibility of using other terms is not excluded. These terms are merely used to describe and explain the nature of the present invention more conveniently; construing them as any of the additional restrictions is contrary to the spirit of the present invention.

LIST OF REFERENCED PARTS

(18) 1 outer barrel 11 brace 111 abutment 112 brace surface 2 inner barrel 21 shoulder 22 neck 3 base 31 slot 4 spear structure 5 expansion space