1. A pipe assembly comprising:
a first pipe having a first end segment and a flexible collar extending from and around a portion of said first end segment;
a second pipe having a second end segment, said second end segment being adjacent said first end segment and in fluid communication with said first end segment;
a sealing member disposed between said collar and said second end segment for providing a fluid seal between said pipes; and
a connection means for interconnecting said pipes such that said sealing member is resiliently clamped between said collar and said second end.
2. A pipe assembly according to claim 1, wherein said flexible collar includes a first flank extending from said first pipe, a second flank extending from said first pipe apart from and generally parallel to said first flank, and a spring portion interconnecting said flanks for allowing elastic displacement of one of said flanks relative to the other of said flanks.
3. A pipe assembly according to claim 2, wherein said first flank has a rounded section between said first end segment and said spring portion for providing a bearing surface for said sealing member.
4. A pipe assembly according to claim 2, wherein said spring portion has a generally semicircular shape.
5. A pipe assembly according to claim 1, wherein said second end segment has a conical-shaped portion acting as a bearing surface for said sealing member.
6. A pipe assembly according to claim 1, wherein said connection means includes a connecting nut coupled to said second pipe, said nut having an end adjacent said collar and a flange extending radially inward from said end, said flange engaging said second flank so as to elastically deform said collar such that said sealing member is elastically clamped between said collar and second end segment.
7. A pipe assembly according to claim 6, wherein said connection means includes groove surrounding an external portion of said second end portion, and wherein said nut includes a projection disposed in said groove for coupling said nut to said second pipe.
8. A pipe assembly according to claim 7, wherein said groove forms a continuous thread and said projection forms a continuous tread complementary to said groove such that said nut is coupled to said second pipe by a screwing action.
9. A pipe assembly according to claim 6, wherein said connection means includes a threaded part fixed to and surrounding at least a portion of said second end segment, said threaded part having an external surface, wherein said groove is formed in said external surface of said threaded part.
10. A pipe assembly according to claim 9, wherein said threaded part is a plastic part that has been molded directly onto said second pipe.
11. A pipe assembly according to claim 9, wherein said threaded part is a metal part that has been pressed onto said second pipe.
12. A pipe assembly according to claim 9, wherein said second pipe includes a rib formed thereon and said threaded part has a complementary channel for receiving said rib such that said threaded part is held in an interlocking manner on said second pipe.
13. A pipe assembly according to claim 1, wherein one of said pipes is adapted for connection to a fuel tank.
14. A fuel tank assembly for a motor vehicle, comprising:
a fuel tank;
a tank pipe having and tank end segment attached to said fuel tank and a second end segment opposite said tank end segment and external to said tank;
a fuel filler pipe in fluid communication with said tank pipe, said filler pipe having a first end segment adjacent said second end segment, a filler end segment acessible from the outside of said vehicle, and a flexible collar extending from and around a portion of said first end segment;
a sealing member disposed between said collar and said second end segment for providing a fluid seal between said pipes; and
a connection means for interconnecting said pipes such that said sealing member is resiliently clamped between said collar and said second end.
15. A fuel tank assembly according to claim 14, wherein said flexible collar includes a first flank extending from said first pipe, a second flank extending from said first pipe apart from and generally parallel to said first flank, and a spring portion interconnecting said flanks for allowing elastic displacement of one of said flanks relative to the other of said flanks.
16. A fuel tank assembly according to claim 15, wherein said first flank has a rounded section between said first end segment and said spring portion for providing a bearing surface for said sealing member.
17. A fuel tank assembly according to claim 15, wherein said spring portion has a generally semicircular shape.
18. A fuel tank assembly according to claim 14, wherein said connection means includes a connecting nut coupled to said second pipe, said nut having an end adjacent said collar and a flange extending radially inward from said end, said flange engaging said second flank so as to elastically deform said collar such that said sealing member is elastically clamped between said collar and second end segment.
19. A fuel tank assembly according to claim 18, wherein said connection means includes groove surrounding an external portion of said second end portion, and wherein said nut includes a projection disposed in said groove for coupling said nut to said second pipe.
20. A fuel tank assembly according to claim 19, wherein said groove forms a continuous thread and said projection forms a continuous tread complementary to said groove such that said nut is coupled to said second pipe by a screwing action.
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 method of machining a cathode used in an electron gun, comprising the steps of:
placing an object to be machined, which is a material of the cathode, and a machining electrode in an electrically insulating oil;
applying a discharge current to the machining electrode; and
machining the object to be machined to have a shape corresponding to the shape of the machining electrode by means of electric discharge machining of the machining electrode,
wherein the machining electrode comprises a disk, recesses formed on a front surface of the disk, a protrusion provided on a back surface of the disk, and a hole for mounting a lead wire for applying discharge current to the machining electrode, and wherein bumps corresponding to the shape of the recesses of the machining electrode are formed on the object to be machined by means of electric discharge machining.
2. A method according to claim 1, wherein the recesses have small holes formed therein and wherein the insulating oil is circulated through the small holes.
3. A method according to claim 1, wherein the object to be machined comprises any one of LaB6, a single crystal, Ta, Hf and tungsten.
4. A method to claim 3, wherein the disk is comprised of tungsten-silver alloy.
5. A method according to claim 4, further comprising the step of polishing the object to be machined to mirror surfaces after the electric discharge machining is completed.
6. A method of machining a cathode used in an electron gun, comprising the steps of:
placing an object to be machined, which is a material of the cathode, and a machining electrode in an electrically insulating oil;
applying a discharge current to the machining electrode; and
machining the object to be machined to have a shape corresponding to the shape of the machining electrode by means of electric discharge machining of the machining electrode,
wherein the machining electrode includes a disk, a plurality of recesses provided on a front surface of the disk and arranged regularly in X and Y directions, a protrusion provided on a back surface of the disk, and a hole for mounting a lead wire for applying discharge current to the machining electrode, and wherein a plurality of bumps corresponding to the shape of the recesses of the machining electrode are formed on the object to be machined by means of electric discharge machining.
7. A method according to claim 6, wherein the object to be machined is cut along two orthogonal directions after the electric discharge machining to be separated into a plurality of cathodes.
8. A method according to claim 7, wherein the object to be machined comprises any one of LaB6, a single crystal, Ta, Hf and tungsten.
9. A method according to claim 8, wherein the disk is comprised of tungsten-silver alloy.
10. A method according to claim 9, further comprising the step of polishing the object to be machined to mirror surfaces prior to the cutting but after the electric discharge machining is completed.
11. A method according to claim 10, wherein a small hole is formed in each recess of the machining electrode so that the insulating oil is circulated through the small holes during the electric discharge machining.