Claims:WE CLAIM:
1. A device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines comprising inlet pipe assembly placed concentrically in the inlet pipe of the rotating machine and return line pipe assembly connected with stationary cryocooler; the bearing housing assembly and rotating sleeve having concentric piping assembly carrying the cold gas and warm gas accommodated in rotating sleeve, and a sealing assembly containing two phase seal, which is assembled with the rotating sleeve.

2. The device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines as claimed in claim 1, wherein the inlet pipe assembly supplies the cold gas to the center pipe of the concentric piping assembly of the HTSC rotor and the warm gas flows through one of the concentric pipes of piping assembly and gets collected in warm gas collection chamber.

3. The device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines as claimed in claim 1 or 2, wherein the warm gas collection chamber transfers the warm gas back to cryocooler in order to cool the gas again and complete one cooling cycle.

4. The device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines as claimed in any of the preceding claims, wherein the sealing assembly is exposed to the warm gas collected in warm gas collection chamber, in which the maximum leakage of the gas is prevented by first phase seal and the further gas leakage is stopped by second stage seal.

5. The device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines as claimed in any of the preceding claims, wherein the second stage seal involves two highly polished surfaces to stop the further gas leakage, in which the rotating face seal rubs on the stationary face seal coating.

6. The device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines as claimed in any of the preceding claims, wherein the cold gas line of the cryocooler is connected with cold gas pipe supplying the cold gas in inner most pipe of piping assembly of the HTSC motor.

7. The device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines as claimed in any of the preceding claims wherein the warm gas flows in one of the pipes of piping assembly following absorption of the heat from the required cooling section of the HTSC motor.

8. The device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines as claimed in any of the preceding claims wherein the bearing housing and sealing assembly housing are joined with intermediate flange.

9. The device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines as claimed in any of the preceding claims wherein the sealing assembly is fastened with sealing enfold assembly separated from atmosphere with a vacuum chamber, which is locked with flange at one end, other end of which is locked with flange.

10. The device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines as claimed in any of the preceding claims is associated with the advantageous features such as herein described.
, Description:A device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines
FIELD OF INVENTION
[001] This invention is directed to a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines.

BACKGROUND/PRIOR ART

[002] The typical operating temperature of the 1st generation HTSC conductor is 25-40K and for the 2nd generation conductor is little higher may be in the range of 50-65 K but certainly lower than the liquid nitrogen temperature i.e. ~ 77K. There is enormous amount of heat load due to thermal mass and also due to high heat in leak from atmosphere. The heat load owing to thermal mass can be removed by initial cooling but heat leak from atmosphere has to be countered by means of continuous cooling with the help of cold gas. The cold gas is cooled with the help of an external cooler which is stationary and is away from HTSC machines. The coolant flows in a closed loop circuit. Hence, a device is required to be devised, which can exchange cold and warm gas from stationary cryocooler to rotary HTSC machine.

[003] Now, reference may be made to the following known patents.

[004] US3991588A: This invention relates to electrical machines employing superconducting rotors and more particularly to apparatus for transferring coolant from a stationary source to such rotors. Cryogenic liquid coolant is transferred from a stationary liquefier through a bayonet to a conduit rotating with the rotor of a superconducting generator, using a cryogenic fluid transfer joint attached to the collector end of the rotor.

[005] US6901955B2: This document describes a cryogenic rotary coupling and in particular the use of such coupling in articulated cryogenic fluid feed lines and in cryogenic propellant rocket engines.

[006] US20120133126Al: The present invention is directed to a cryo-rotary joint which lends itself to extreme downsizing by using a structure in which a cylindrical relatively rotating member is implemented for a sealing portion between a rotary part and stationary part of the rotary joint and a refrigerant tube is passed internally through the relatively rotating member.

[007] However, none of the above can meet the requirements of present invention, for which it is developed. Therefore, the invention introduces a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines.

OBJECTS OF THE INVENTION

[008] An object of the invention is to provide a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines which transfers the cold gas from stationary cryocooler to rotary HTSC rotating machines.

[009] Another object of the invention is to provide a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines which collects the warm gas from HTSC rotating machines and sends the same back to stationary crycooler.

[0010] Still another object of the invention is to provide a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines which prevents the cold gas leakage during transferring the cold gas from stationary frame to rotating frame.

[0011] Yet another object of the present invention is to provide a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines that prevents mixing of cold gas and warm gas in rotary coupling.

[0012] Further object of the present invention is to provide a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines which reduces the heat in leak from atmosphere to the cold gas.

[0013] Still further object of the present invention is to provide a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines which prevents any contamination of cold gas as well as of warm gas.

SUMMARY OF THE INVENTION

[0014] According to this invention , there is provided a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines comprising inlet pipe assembly placed concentrically in the inlet pipe of the rotating machine and return line pipe assembly connected with stationary cryocooler; the bearing housing assembly and rotating sleeve having concentric piping assembly carrying the cold gas and warm gas accommodated in rotating sleeve, and a sealing assembly containing two phase seal, which is assembled with the rotating sleeve.

[0015] The inlet pipe assembly supplies the cold gas to the center pipe of the concentric piping assembly of the HTSC rotor and the warm gas flows through one of the concentric pipes of piping assembly and gets collected in warm gas collection chamber.

[0016] The warm gas collection chamber transfers the warm gas back to cryocooler in order to cool the gas again and complete one cooling cycle.

[0017] The sealing assembly is exposed to the warm gas collected in warm gas collection chamber, in which the maximum leakage of the gas is prevented by first phase seal and the further gas leakage is stopped by second stage seal.

[0018] The second stage seal involves two highly polished surfaces to stop the further gas leakage, in which the rotating face seal rubs on the stationary face seal coating.

[0019] The cold gas line of the cryocooler is connected with cold gas pipe supplying the cold gas in inner most pipe of piping assembly of the HTSC motor.

[0020] The warm gas flows in one of the pipes of piping assembly following absorption of the heat from the required cooling section of the HTSC motor.

[0021] The bearing housing and sealing assembly housing are joined with intermediate flange.

[0022] The sealing assembly is fastened with sealing enfold assembly separated from atmosphere with a vacuum chamber, which is locked with flange at one end, other end of which is locked with flange.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[0023] Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawings of the exemplary embodiments and wherein:-

FIG-1 shows: Schematic drawing of rotary coupling of device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines according to the present invention.

FIG-2 shows: Bearing housing assembly and rotating sleeve of the device of the present invention.

FIG-3 shows: Sealing assembly of the device in accordance with the present invention.

FIG-4 shows: Sealing assembly housing and warm gas collection chamber of the device of invention.

DETAIL DESCRIPTION OF THE PRESENT INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS

[0024] The present invention makes a disclosure in respect of a device to exchange the coolant media in high temperature superconducting (HTSC) rotating machines.

[0025] Fig 1 represents the schematic of rotary device to exchange the cold and warm fluid from stationary to rotary part ofHTSC electrical rotating machine. The inlet pipe assembly 102 is connected with stationary cryo-cooling system. This inlet pipe is kept concentrically in the inlet pipe of HTSC electrical rotating machines. The return line pipe assembly 103 is also connected with stationary cryocooler to complete the cooling circuit. First stage sealing 109 stops the maximum amount of return gas leakage, which is further stopped by second stage sealing 110. The sealing assembly 105 is fastened with sealing enfold assembly. The other end of sealing assembly (105) is secured with rotating sleeve 107. The rotating sleeve 107 is supported by bearing housing 106. The inlet pipe assembly 102 supplies the cold gas to the center pipe of the concentric piping assembly 108 of the HTSC rotor. The warm gas flows through one of the concentric pipes of piping assembly 108 and gets collected in warm gas collection chamber. This warm gas collection chamber 111 transfers the warm gas back to cryocooler in order to cool the gas again and complete one cooling cycle. The sealing enfold assembly 104 is in thermal contact with inlet pipe assembly 102 which is at cryogenic temperature. Further, this sealing enfold assembly is separated from atmosphere with a vacuum chamber 101.

[0026] Now, reference may be made to fig. 2 illustrating the bearing housing assembly and rotating sleeve. The concentric piping assembly carrying the cold gas and warm gas is housed in rotating sleeve 206. This sleeve 206 is supported on two bearings 201. The balance is maintained by placing a bearing spacer 204 which keeps the bearing at desired place. The inner race of the bearing is supported on rotating sleeve 206 whereas the outer race of the bearing is supported by a support pad 205. The vacuum sleeve 101 is anchored at flange 202 with bearing housing. One leakage port 207 is provided to prevent the cold gas to reach to the bearing. The intermediate flange 203 of bearing housing assembly joins the sealing enfold assembly. The rotating device and HTSC rotor are integrated with flange 209. The knife edged metal gasket flange 208 indents on metal gasket which completely seals the gas even at very low temperature.

[0027] Now, referring to Fig. 3 indicating the sealing assembly which contains two phase seal. The sealing assembly is assembled with rotating sleeve (206) with a sharp edged metal gasket flange 301. Further, the sealing assembly is exposed to the warm gas only which is collected in warm gas collection chamber 111. The maximum leakage of the gas is stopped by first phase seal with the help of a plurality of seal rings 307. The further gas leakage is stopped by second stage seal. In the second stage seal, two highly polished surfaces are used to stop the further gas leakage. The Rotating face seal 304 rubs on the stationary face seal coating 303. The surface finish of these two faces is in the order of 2-3 light bend. The rotating seal face coating is provided on the rotary seal holder 302. The stationary face seal 304 is inserted in stationary face seal holder 306 with a below 305 to put pressure on seal faces. This sealing assembly 105 and warm gas collection chamber 111 join with the knife edge metal gasket flange 308.

[0028] Fig 4 represents the sealing assembly housing and warm gas collection chamber. The cold gas line of the cryo-cooling system is connected with cold gas pipe connection 401. This cold gas pipe supplies the cold gas in inner most pipe of piping assembly 408 of HTSC motor. After picking the heat from the required cooling section of HTSC motor, the warm gas flows in one of the pipes of piping assembly 408. The warm gas and cold gas are separated by proper insulation to prevent heat transfer. The warm gas gets collected in warm collection chamber 403, which is sent back to cryo-cooling system through return gas pipe connection 402. The sealing assembly 105 and warm gas collection chamber 403 are joined with metal gasket flange 407 by means of metal gasket 406 so as to ensure no leakage of gas at even very low temperatures. The bearing housing and sealing assembly housing are joined with intermediate flange 405. The vacuum chamber 101 is locked with flange 202 at one end, other end of which is locked with flange 404.

Features of the Invention:

[0029] -Transfers the cold gas from a stationary frame to a rotary frame.

- Collects the return warm gas from rotary frame and supplies back to stationary frame for re-cooling of the warm gas.
- The gas leakage from this device is negligible during operation thereof.
- Avoids mixing of cold gas and warm gas during gas exchange processes.
- Reduction in the heat in-leak to cold gas as well as warm gas to minimum.
- Prevents contamination of the cold gas and warm gas by any other element in the course of exchange process.

[0030] Reference Numerals

Fig. 1
101-Vacuum sleeve
102-Inlet pipe assembly
103-Return line pipe assembly
1 04-Sealing enfold assembly
1 05-Selaing assembly
1 06-Bearing housing assembly
107-Rotating shaft
108-Concentric piping assembly from HTSC rotor
109-First stage seal
110-Second stage seal
111-Warm gas collection chamber

Fig. 2
201-Ball Bearings
202-Vacuum sleeve holding flange
203-Intermediate flange
204-Bearing spacer
205-Supporting pad
206-Rotating sleeve
207-Leakage port
208-Metal gasket flange
209-Shaft flange

Fig. 3
301-Metal gasket flange
302-Stationary face seal holder
303-Face seal coating
304-Stationary face seal coating
305-Bellow
306-Stationary face seal holder
307-Seal ring
308-Metal gasket flange

Fig. 4
40 1-Cold gas pipe connection
402-Return gas pipe connection
403-Warm gas collection chamber
404-Vacuum sleeve holding flange
405-Intermediate flange
406-Metal gasket
407-Metal gasket flange
408-Piping assembly

[0031] It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims:-