초록 ▼

A heat shield assembly for use in a crystal puller has an outer reflector interposed between the ingot and the crucible as the ingot is pulled from the molten source material. A cooling shield is interposed between the ingot and the outer reflector whereby the cooling shield is exposed to heat radia

A heat shield assembly for use in a crystal puller has an outer reflector interposed between the ingot and the crucible as the ingot is pulled from the molten source material. A cooling shield is interposed between the ingot and the outer reflector whereby the cooling shield is exposed to heat radiated from the ingot for increasing the rate at which the ingot is cooled, thereby increasing the axial temperature gradient of the ingot. In a further embodiment, an inner shield panel is disposed generally intermediate the cooling shield and the ingot in radially spaced relationship with the cooling shield and is constructed of a material substantially transparent to radiant heat from the ingot.

대표청구항 ▼

A heat shield assembly for use in a crystal puller has an outer reflector interposed between the ingot and the crucible as the ingot is pulled from the molten source material. A cooling shield is interposed between the ingot and the outer reflector whereby the cooling shield is exposed to heat radia

A heat shield assembly for use in a crystal puller has an outer reflector interposed between the ingot and the crucible as the ingot is pulled from the molten source material. A cooling shield is interposed between the ingot and the outer reflector whereby the cooling shield is exposed to heat radiated from the ingot for increasing the rate at which the ingot is cooled, thereby increasing the axial temperature gradient of the ingot. In a further embodiment, an inner shield panel is disposed generally intermediate the cooling shield and the ingot in radially spaced relationship with the cooling shield and is constructed of a material substantially transparent to radiant heat from the ingot. g device operates in response to energy from an rf heating source. 23. Method of claim 17 wherein the distal portion of said catheter is curved and the cutting device is a needle knife. 24. Method for orientating a tissue cutting device located in a distal portion of a first lumen of an endoscopic catheter which comprises: providing said catheter with a second lumen having a reciprocating cable therein, said second lumen having a fixed member therein for imparting rotary motion to said cable when reciprocated therethrough and a sliding member attached to said cable distally of said fixed member; and reciprocating said cable to cause rotation of said sliding member and at least a distal portion of said catheter to orient said cutting device. 25. Method of claim 24 wherein said second lumen is non-round in cross section. 26. Method of claim 25 wherein said second lumen is square in cross section. 27. Method of claim 25 wherein said sliding member is square in cross section. 28. Method of claim 24 wherein said cable has spiral threads on an outer circumference thereof. 29. Method of claim 28 wherein said fixed member includes a spiral thread on an inner circumference thereof. 30. Method of claim 24 wherein said distal portion of said catheter is curved and the cutting device is a needle knife. 31. In an endoscopic catheter having a cable actuated needle knife in a lumen thereof, said needle knife being deployable from a distal end of said catheter, the improvement for substantially preventing movement of said needle knife after deployment which comprises a distally positioned fixed stabilizing element in said lumen internally engaging said needle knife cable to prevent such movement. 32. Catheter of claim 31 wherein said needle knife cable includes a spiral thread on an outer circumference thereof. 33. Catheter of claim 32 wherein said fixed stabilizing element includes a spiral thread on an inner circumference thereof. 34. Catheter of claim 33 further comprising a pivot element included within said needle knife cable. 35. Catheter of claim 34 wherein said pivot element is proximal of said fixed stabilizing element. 36. Catheter of claim 35 wherein said needle knife cable includes a spiral thread on an outer circumference thereof. 37. Catheter of claim 36 wherein said fixed stabilizing element includes a spiral thread on an inner circumference thereof. 38. In an endoscopic catheter having a cable actuated needle knife in a first lumen thereof, said needle knife being deployable from a distal end of said catheter, the improvement for orienting the cutting device and for substantially preventing movement of said needle knife after deployment which comprises: providing said catheter with a second lumen having a reciprocating cable therein, said second lumen having a fixed member therein for imparting rotary motion to said cable when reciprocated therethrough; reciprocation of said cable causing rotation of at least a distal portion of said catheter to orient said cutting device, and providing a distally positioned fixed stabilizing element in said first lumen internally engaging said needle knife cable to prevent such movement. 39. Catheter of claim 38 wherein said reciprocating cable has spiral threads on an outer circumference thereof. 40. Catheter of claim 39 wherein said fixed member includes a spiral thread on an inner circumference thereof. 41. Catheter of claim 38 wherein said needle knife operates in response to energy from an rf heating source. 42. Catheter of claim 38 wherein said distal portion of said catheter is curved. 43. Catheter of claim 38 wherein said needle knife cable includes a spiral thread on an outer circumference thereof. 44. Catheter of claim 43 wherein said fixed stabilizing element includes a spiral thread on an inner circumference thereof. 45. Catheter of claim 38 further comprising a pivot element included within said needle knife cable. 46. Catheter of claim 45 wherein said pivot element