1. A refrigerator comprising:
an inner case configured to form a storage space, the inner case comprising a first communication hole;
an outer case spaced apart from the inner case, the outer case comprising a second communication hole;
a first support plate disposed on a surface of at least one of the inner case and the outer case, and in a vacuum space between the inner case and the outer case, the first support plate comprising a third communication hole;
spacers disposed between the first support plate and at least the other one of the inner case and the outer case, the spacers being fixed to the first support plate to support and maintain the vacuum space between the inner case and the outer case; and
a connection pipe connecting the first communication hole to the second communication hole, the connection pipe passing through the vacuum space, an external portion of the connection pipe corresponding to the vacuum space and an internal portion of the connection pipe being separated from the vacuum space,
wherein the third communication hole is formed between the first communication hole and the second communication hole, and a diameter of the third communication hole is larger than a diameter of the first communication hole or a diameter of the second communication hole,
wherein the connection pipe comprises a first pipe part and a second pipe part,
wherein a diameter of the external portion of the connection pipe is greater than a diameter of the first communication hole, and the first pipe part is welded to the outer case and the second pipe part is welded to the inner case, and
wherein each of the spacers has a cylindrical shape and comprises convexly curved ends to be received in a plurality of grooves.
2. The refrigerator according to claim 1, wherein the connection pipe comprises a lateral wall corrugation part having an inner diameter area welded to a respective inner diameter area of another piece of the corrugation part and an outer diameter area welded to a respective outer diameter are of another piece of the corrugation part.
3. The refrigerator according to claim 1, wherein:
the first support plate comprises reinforced plastic, and
the connection pipe comprises metal and is welded to the inner case and the outer case.
4. The refrigerator according to claim 1, wherein a diameter of the outer diameter area is greater than a distance between two neighboring spacers.
5. The refrigerator according to claim 2, wherein the first pipe part comprises an upper pipe part and the second pipe part comprises a lower pipe part.
6. The refrigerator according to claim 5, wherein a distance between the upper pipe part and the lower pipe part is the same as a distance between the first support plate and the other one of the inner case and the outer case.
7. The refrigerator according to claim 5, wherein a distance between the first support plate and the other one of the inner case and the outer case is greater than a distance between the upper pipe part and the lower pipe part.
8. The refrigerator according to claim 5, wherein a portion of the upper pipe part or a portion of the lower pipe part traverses the third communication hole.
9. A refrigerator comprising:
an inner case comprising a first communication hole;
an outer case spaced apart from the inner case, the outer case comprising a second communication hole;
a connection pipe connecting the first communication hole to the second communication hole, the connection pipe comprising a lateral wall corrugation part having an inner diameter area and an outer diameter area, the connection pipe comprising a first pipe part and a second pipe part,
wherein a diameter of the outer diameter area is greater than a diameter of the first communication hole, and the first pipe part is welded to the outer case and the second pipe part is welded to the inner case, and
wherein the first pipe part comprises an upper pipe part and the second pipe part comprises a lower pipe part.
10. The refrigerator according to claim 9, wherein a diameter of the inner diameter area is the same as the diameter of the first communication hole.
11. The refrigerator according to claim 9, wherein:
the diameter of the outer diameter area is greater than a diameter of the second communication hole, and
the diameter of the inner diameter area is the same as the diameter of the second communication hole.
12. The refrigerator according to claim 9, wherein the lateral wall corrugation part comprises a metal thin film having a thickness between 0.05 mm and 0.2 mm.
13. The refrigerator according to claim 9, wherein an inner surface of the connection pipe is coated by plastic.
14. The refrigerator according to claim 13, wherein a first side wall of the lateral wall corrugation part directly contacts the plastic coating of the connection pipe and a second side wall of the lateral wall corrugation part directly contacts the one of the inner case or the outer case.
15. The refrigerator according to claim 9, wherein the connection pipe comprises metal and is welded to the inner case and the outer case.
16. The refrigerator according to claim 9, wherein a cumulative height of the upper pipe part, the lower pipe part, and the lateral wall corrugation part is the same as a distance between the inner case and the outer case.
17. The refrigerator according to claim 9, wherein a distance between the inner case and the outer case is greater than a distance between the upper pipe part and the lower pipe part.
18. A refrigerator comprising:
an inner case comprising a first communication hole;
an outer case spaced apart from the inner case, the outer case comprising a second communication hole;
spacers configured to maintain a vacuum space between the inner case and the outer case;
a connection pipe connecting the first communication hole to the second communication hole, the connection pipe passing through the vacuum space, an external portion of the connection pipe corresponding to the vacuum space and an internal portion of the connection pipe being separated from the vacuum space,
wherein the connection pipe comprises a first pipe part welded to the outer case and a second pipe part welded to the inner case,
wherein an outer diameter of a lateral wall portion of the connection pipe is greater than a diameter of the first communication hole, is spaced apart a predetermined distance from the spacers, and does not interfere with the spacers, and
wherein the first pipe part comprises an upper pipe part and the second pipe part comprises a lower pipe part.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A back-up tong for assembling or disassembling threaded tubing joints, comprising:
a first gripping mechanism;
a second gripping mechanism;
the first gripping mechanism having a first plurality of jaws for engaging a tubing to prevent rotation of the tubing in a clockwise direction; and
the second gripping mechanism having a second plurality of jaws for engaging the tubing to prevent rotation of the tubing in a counter-clockwise direction;
a first plate, a second plate, and a third plate, where the first gripping mechanism is housed between the first and second plates and where the second gripping mechanism is housed between the second and third plates, and where at least one jaw in the first plurality of jaws and at least one jaw in the second plurality of jaws is connected to the second plate.
2. The back-up tong of claim 1, where the first gripping mechanism further includes a first rotatably mounted ring gear in mesh with the jaws in the first plurality of jaws.
3. The back-up tong of claim 1, where the second gripping mechanism further includes a second rotatably mounted ring gear in mesh with the jaws in the second plurality of jaws.
4. (canceled)
5. The back-up tong of claim 14 where each jaw in the first plurality of jaws is pivotally connected to the first and second plates.
6. The back-up tong of claim 14 where each jaw in the second plurality of jaws is pivotally connected to second and third plates.
7. The back-up tong of claim 4, where each jaw in the first plurality of jaws is pivotally connected to the first and second plates and each jaw in the second plurality of jaws is pivotally connected to the second and third plates, and where each jaw of the first plurality of jaws has a pivot point and each jaw of the second plurality of jaws has a pivot point and where the pivot point of each jaw in the first plurality of jaws is axially offset from the pivot points of each jaw in the second plurality of jaws.
8. The back-up tong of claim 7 where each jaw in the first plurality of jaws is pivotally connected by a pivot pin extending through aligning holes in the first and second plates and the jaws in the first plurality of jaws, and where each jaw in the second plurality of jaws is pivotally connected by a pivot pin extending through aligning holes in the second and third plates and the jaws in the second plurality of jaws.
9. A back-up tong for assembling or disassembling threaded tubing joints, comprising:
a tong head having a top plate, an intermediate plate and a bottom plate,
a first gripping mechanism positioned between the top and intermediate plates;
a second gripping mechanism positioned between the intermediate and bottom plates;
the first gripping mechanism having a first ring gear rotatably mounted between the top and intermediate plates and a plurality of first jaws pivotally connected to the top and intermediate plates and in mesh with the first ring gear such that rotation of the first ring gear pivots the first jaws between a retracted position and a gripping position; and
the second gripping mechanism having a second ring gear rotatably mounted between the intermediate and bottom plates and a plurality of second jaws pivotally connected to the intermediate and bottom plates and in mesh with the second ring gear such that rotation of the second ring gear pivots the second jaws between a retracted position and a gripping position
10. The back-up tong of claim 9, where the first jaws each have a toothed end in mesh with the first ring gear and where the second jaws each have a toothed end in mesh with the second ring gear.
11. The back-up tong of claim 10, where both the first and second ring gears have teeth along an interior circumference for meshing with the first jaws and second jaws respectively.
12. The back-up tong of claim 9 where an outer circumference of the first ring gear is supported by at least two radial spacers mounted to the top plate.
13. The back-up tong of claim 9 where an outer circumference of the second ring gear is supported by at least two radial spacers mounted to the bottom plate.