Claims
- 1. A tubular body comprising:
- a series of periodically wavy recessed ribs formed on the external surface of the tubular body, said recessed ribs having a specific depth and a specific angle and a specific wave form about a base line at a center of the wave form, plural base lines being formed as rings at a specific angle to a plane perpendicular to a longitudinal axis of the tubular body; and
- a corresponding series of projecting ribs having the same specific wave form about the same base line formed on the internal surface of the tubular body,
- the specific wave form being selected from a group of wave forms consisting of a sinusoid wave form, a saw tooth wave form, a wave form made on continuously connected alternating opposite semicircular curves, and a rectangular wave form.
- 2. A tubular body of claim 1, wherein the base line of said recessed ribs and projecting ribs are, most desirably, spirally set in the range of lead angles 1.degree..about.30.degree..
- 3. A tubular body of claim 1, wherein the depth of said recessed ribs is most desirably set at 0.5.about.5 mm.
- 4. A tubular body of claim 1, wherein said recessed rib is formed as an alternate continuation of circular part and straight part.
- 5. A tubular body of claim 4, wherein the period of the waveform of said recessed ribs is most desirably set at 3.5.about.50 mm.
- 6. A tubular body of claim 4, wherein the angle of intersection between the base line of said recessed rib and said straight part is most desirably set at 5.degree..about.60.degree..
- 7. A tubular body of claim 1, wherein said recessed rib is a sine wave of Sin .beta..
- 8. A tubular body of claim 1, wherein the value of .beta. is most desirably set at 5.degree..about.60.degree..
- 9. A tubular body of claim 1, wherein said recessed rib is a cosine wave of Cos .beta..
- 10. A tubular body of claim 9, wherein the value of .beta. is most desirably set at 5.degree..about.60.degree..
- 11. A tubular body of claim 1, wherein said recessed rib is a saw-tooth wave.
- 12. A tubular body of claim 11, wherein the period of said saw-tooth wave is most desirably set at 3.5.about.50 mm.
- 13. A tubular body of claim 11, wherein the angle of intersection between the base line of said recessed rib and said saw-tooth wave is most desirably set at 5.degree..about.60.degree..
- 14. A tubular body of claim 1, wherein said recessed rib is formed as an alternate continuation of semi-circular part and its inversion.
- 15. A tubular body of claim 14, wherein the period of the waveform of said recessed rib is most desirably set at 3.5.about.50 mm.
- 16. A tubular body of claim 14, wherein the angle between the base line of recessed rib and the transition line from said circular part to its inversion is most desirably set at 1.degree..about.90.degree..
- 17. A tubular body of claim 1, wherein said recessed rib is a square wave.
- 18. A tubular body of claim 17, wherein the period of said square wave is most desirably set at 3.5.about.50 mm.
- 19. A tubular body of claim 17, wherein the angle of intersection between the base line of recessed rib and said square wave is most desirably set at 1.degree..about.90.degree..
- 20. A heat exchanger comprising a plurality of tubular bodies of claim 1 having aligned axes and adjacent ends, and having framework means holding the adjacent ends.
- 21. A tubular body comprising:
- a series of periodically wavy recessed ribs formed on the external surface of the tubular body, said recessed ribs having a specific depth and a specific angle and a specific wave form about a base line at a center of the wave form, the base line being of a ring fashion formed at a specific angle to a plane perpendicular to a longitudinal axis of the tubular body; and
- a corresponding series of projecting ribs having the same specific wave form about the same base line formed on the internal surface of the tubular body,
- the specific wave form being selected from a group of wave forms consisting of sinusoid wave form, a saw tooth wave form, a wave form made of continuously connected alternating opposite semicircular curves, and a rectangular wave form.
- 22. A tubular body of claim 21, wherein the basic line of recessed ribs and projecting ribs are of a ring fashion.
- 23. A tubular body of claim 22, wherein the ring fashion of said baseline is desirably cut at a specific angle 1.degree..about.30.degree. from a line perpendicular to the longitudinal axis of the tubular body.
Priority Claims (1)
Number |
Date |
Country |
Kind |
51-59863 |
May 1976 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 7,530, filed Jan. 29, 1979, now abandoned, which is a division of application Ser. No. 776,215, filed Mar. 10, 1977, now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (2)
Number |
Date |
Country |
2043459 |
Mar 1972 |
DEX |
11612 OF |
Jan 1899 |
GBX |
Divisions (1)
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Number |
Date |
Country |
Parent |
776215 |
Mar 1977 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
7530 |
Jan 1979 |
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