1. An apparatus for manufacturing a silicon carbide single crystal by growing the silicon carbide single crystal on a surface of a seed crystal made from a silicon carbide single crystal substrate by supplying a material gas for silicon carbide from below the seed crystal, the apparatus comprising:
a cylindrical tube-shaped heating container having an inner wall surface defining a reaction chamber;
a base located in the reaction chamber of the heating container and having a first side and a second side opposite to the first side, the seed crystal mounded on the first side of the base;
a first purge gas inlet provided to the inner wall of the heating container to cause a purge gas to flow along the inner wall surface of the heating container;
a purge gas source for supplying the purge gas to the first purge gas inlet;
a second purge gas inlet provided to an outer wall of the base to cause the purge gas to flow along the outer wall surface of the base; and
a purge gas introduction mechanism for supporting the base and for supplying the purge gas to the base from the second side of the base.
2. The apparatus according to claim 1, wherein
the first purge gas inlet extends circularly along the inner wall surface of the heating container in a circumferential direction of the heating container.
3. The apparatus according to claim 1, wherein
the heating container includes a tube portion and a first guide portion having a ring shape, and
the first guide portion is spaced from the inner wall surface of the tube portion to form the first purge gas inlet therebetween.
4. The apparatus according to claim 3, wherein
the first guide portion is spaced from the inner wall surface of the tube portion by a predetermined constant distance, and
the inner wall surface of the tube portion is parallel to an outer wall surface of the first guide portion.
5. The apparatus according to claim 3, wherein
an inner diameter of the first guide portion is increased in a flow direction of the material gas.
6. The apparatus according to claim 5, wherein
an inner wall surface of the first guide portion is tapered so that the inner diameter of the first guide portion is increased in the flow direction of the material gas, and
the inner wall surface of the first guide portion and the outer wall surface of the first guide portion form an angle of 45 degrees or less.
7. The apparatus according to claim 3, wherein
the tube portion of the heating container has a first tube part and a second tube part communicating with the first part,
an inner diameter of the first tube part is gradually reduced in a flow direction of the material gas,
the first tube part is located on the downstream side of the second tube part in the flow direction of the material gas, and
the first tube part is located on the downstream side of the first purge gas inlet in the flow direction of the material gas.
8. The apparatus according to claim 1, wherein
the first purge gas inlet comprises a plurality of first purge gas inlets.
9. The apparatus according to claim 1, wherein
the heating container is coated with a refractory metal carbide.
10. The apparatus according to claim 1, further comprising:
a second guide portion having a ring shape, wherein
the second guide portion is spaced from the outer wall surface of the base to form the second purge gas inlet therebetween.
11. The apparatus according to claim 10, wherein
the second guide portion is spaced from the outer wall surface of the base by a predetermined constant distance, and
an inner wall surface of the second guide portion is parallel to the outer wall surface of the base.
12. The apparatus according to claim 10, wherein
the purge gas introduction mechanism has a pipe member through which the purge gas is supplied to the base,
the base includes a coupling portion coupled to the pipe member and a mounting portion having a first side and a second side opposite to the first side,
the first side of the mounting portion defines a mounting surface where the seed crystal is mounded,
the coupling portion includes a cylindrical tube portion fitted with the second side of the mounting portion,
an outer wall surface of the tube portion of the coupling portion defines the outer wall surface of the base,
the mounting portion has the second guide portion,
the second guide portion projects perpendicularly from the second side of the mounting portion in such a manner that an inner wall surface of the second guide portion faces and is spaced from the outer wall surface of the tube portion of the coupling portion to form the second purge gas inlet therebetween, and
the second purge gas inlet is configured in such a manner that the purge gas that is discharged through the second purge gas inlet flows along the outer wall surface of the tube portion of the coupling portion in the same direction as a flow direction of the material gas.
13. The apparatus according to claim 12, wherein
an outer diameter of the second guide portion is reduced in the flow direction of the material gas.
14. The apparatus according to claim 10, wherein
the purge gas introduction mechanism has a pipe member through which the purge gas is supplied to the base,
the base includes a coupling portion coupled to the pipe member and a mounting portion having a first side and a second side opposite to the first side,
the first side of the mounting portion defines a mounting surface where the seed crystal is mounded,
the coupling portion includes a cylindrical tube portion fitted with the second side of the mounting portion,
the tube portion of the coupling portion has a thicker portion defining a first inner diameter and a thinner portion defining a second inner diameter larger than the first inner diameter,
the mounting portion has a cylindrical tube with a bottom portion that closes a first end of the tube,
a second end of the tube of the mounting portion is fitted into the tube portion of the coupling portion so that the coupling portion and the mounting portion are connected together,
an inner wall surface of the thinner portion of the tube portion of the coupling portion is spaced from an outer wall surface of the tube of the mounting portion to form the second purge gas inlet therebetween, and
the second purge gas inlet is configured in such a manner that the purge gas that is discharged through the second purge gas inlet flows along the outer wall surface of the tube of the mounting portion in an opposite direction to a flow direction of the material gas.
15. The apparatus according to claim 10, wherein
the purge gas introduction mechanism has a pipe member through which the purge gas is supplied to the base,
the base includes a coupling portion coupled to the pipe member and a mounting portion where the seed crystal is mounted,
the coupling portion has a hollow disc shape with an inner space,
the mounting portion includes a circular plate and a solid cylinder,
the circular plate has a first side defining a mounting surface where the seed crystal is mounted and a second side opposite to the first side of the circular plate,
the solid cylinder of the mounting portion is located on the second side of the circular plate and fitted into the inner space of the coupling portion so that the coupling portion and the mounting portion are connected together,
the second side of the circular plate of the mounting portion is spaced from the coupling portion to form the second purge gas inlet therebetween, and
the second purge gas inlet is configured in such a manner that the purge gas is discharged through the second purge gas inlet from an outer edge of the seed crystal in a radial outward direction of the base and that the discharged purge gas flows along an outer wall surface of the coupling portion.
16. The apparatus according to claim 10, wherein
the purge gas introduction mechanism has a pipe member through which the purge gas is supplied to the base,
the base includes a frustum and a cylindrical tube,
the frustum has a top surface and a bottom surface defining a mounting surface where the seed crystal is mounted,
the tube of the base projects perpendicularly from the top surface of the frustum and is fitted into an end of the pipe member,
the second guide portion is provided to the end of the pipe member, and
an inner diameter of the second guide portion is increased with a distance from the end of the pipe member,
the frustum is spaced from the second guide portion to form the second purge gas inlet therebetween, and
the second purge gas inlet is configured in such a manner that the purge gas that is discharged through the second purge gas inlet flows along an outer wall surface of the frustum in an opposite direction to a flow direction of the material gas.
17. The apparatus according to claim 10, wherein
the purge gas introduction mechanism has a pipe member through which the purge gas is supplied to the base,
the base includes a frustum and a cylindrical tube,
the frustum has a top surface and a bottom surface defining a mounting surface where the seed crystal is mounted,
the tube of the base projects perpendicularly from the top surface of the frustum and is fitted into an end of the pipe member,
the second guide portion has a hollow frustum shape and is spaced from an outer wall surface of the frustum to form the second purge gas inlet therebetween,
the top surface of the frustum is recessed to form a recess,
the recess communicates with the pipe member,
an inner wall surface of the recess is provided with communication holes that are arranged at a regular interval in a circumferential direction of the recess,
the second guide portion covers the communication holes 94b to change a direction of flow of the purge gas that is discharged through the communication hole, and
the second purge gas inlet is configured in such a manner that the purge gas that is discharged through the second purge gas inlet flows along the outer wall surface of the frustum not only in the same direction as a flow direction of the material gas but also in an opposite direction to the flow direction of the material gas.
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 leisure chair comprising:
a base adapted to be placed on a ground, with the base including an upper end having a supporting portion, with the base further including a rear end;
a seat mounted on the upper end of the base;
a backrest including a lower end pivotably connected to the rear end of the seat, with the backrest having a rearward inclination angle relative to the seat, with the rearward inclination angle being adjustable;
a connection seat mounted between the base and the seat, with the connection seat including a lower coupling portion, two pivotal rod units, and an upper coupling portion, with the lower coupling portion coupled with the supporting portion of the seat, with the lower coupling portion including two sides, with a lower coupling plate provided at each of the two sides of the lower coupling portion and extending in a frontback direction of the seat, with each of the two pivotal rod units pivotably connected to and movable relative to one of the lower coupling plates, with each of the two pivotal rod units including a front, vertical pivotal rod substantially extending perpendicularly to the ground, a rear, vertical pivotal rod substantially extending perpendicularly to the ground, and a connecting rod extending in the frontback direction of the seat, with the front, vertical pivotal rod of each of the two pivotal rod units having a lower end pivotably connected to a front end of the lower coupling plate, with the rear, vertical pivotal rod of each of the two pivotal rod units having a lower end pivotably connected to a rear end of one of the two lower coupling plates, with the connecting rod of each of the two pivotal rod units having a rear end pivotably connected to an upper end of one of the rear, vertical pivotal rods, with the connecting rod of each of the two pivotal rod units further having a front end located in front of a front end of one of the front, vertical pivotal rods, with the upper coupling portion including two upper coupling plates extending in the frontback direction of the seat, with the two upper coupling plates fixed to the seat, with each of the two upper coupling plates pivotably connected to the upper end of the front, vertical pivotal rod of one of the two pivotal rod units;
a legrest unit including two link units movable between an extended position and a folded position, with each of the two link units including a rear end pivotably connected to the front end of one of the upper coupling plates and one of the connecting rods;
an adjusting unit including a driving rod pivotably connected to a rear end of the legrest unit, wherein when the driving rod moves forwards, the two link units move to the extended position, the connecting rods are actuated to move the two pivotal link units, and the upper coupling portion moves forwards relative to the lower coupling portion.
2. The leisure chair as claimed in claim 1, with the front end of each of the two upper coupling plates including two front pivotal portions, with the rear end of each of the two link units including first and second links pivotably connected to the two front pivotal portions, respectively, with the first link located behind the second link and pivotably connected with the front end of one of the connecting rods.
3. The leisure chair as claimed in claim 2, with each of the two upper coupling plates including a through-hole, with a transverse connecting beam coupled in and extending through the through-holes of the two upper coupling plates, with a side coupling portion mounted to an outer side of one of the two upper coupling plates and having an axle, with the adjusting unit further including a control rod, two swaying rods, and two first springs, with the control rod including an upper end having a gripping portion and a lower end having a pivotal portion pivotably connected to the axle of the side coupling portion, with the control rod including a pressing portion above the pivotal portion thereof, with each of the two swaying rods mounted to the outer side of one of the upper coupling plates, with each of the two swaying rods including a front end having an engagement hole and a rear end, with the transverse connecting beam of the connection seat securely engaged in the engagement holes of the two swaying rods, with the transverse connecting beam and the two swaying rods jointly moveable, with the rear end of each of the two swaying rods pivotably connected to a rear end of the driving rod, with each of the two swaying rods further including an intermediate portion having a peg, with each of two first springs having first and second ends, with the first end of each of the two first springs attached to the peg of one of the two swaying rods, with the second end of each of the two first springs attached to a protrusion of one of the two upper coupling plates, with an imaginary line extending through the engagement hole of each of the two swaying rods and the protrusion of one of the two upper coupling plates, with the rear end of the driving rod pivotably connected to the two swaying rods, with the driving rod further including a front end pivotably connected to the first link of one of the two link units,
wherein when the legrest unit is in the storage position, the pegs of the two swaying rods located above the imaginary lines, and
wherein when the control rod moves forwards, the pressing portion presses against and actuates the two swaying rods to move, and the legrest unit moves to the extended position under elastic forces provided by the first springs when the pegs of the two swaying rods located below the imaginary lines.
4. The leisure chair as claimed in claim 3, with the adjusting unit further including a second spring attached between the control rod and the side coupling portion.
5. The leisure chair as claimed in claim 3, further comprising a transverse rod interconnected between the two front, vertical pivotal rods and a transverse rod interconnected between the two upper coupling plates.
6. The leisure chair as claimed in claim 4, with the side coupling portion including a rear board having an intermediate section with a bend, with the bend of the intermediate section of the rear board having an abutment portion, with the control rod including a push portion, and with the push portion of the control rod abutting the abutment portion to limit a maximum displacement angle of the control rod.
7. The leisure chair as claimed in claim 3, with each of the two lower coupling plates of the connection seat further including a soft buffering member mounted to an outer side thereof, and with the rear, vertical pivotal rods abutting the soft buffering members during movement of the rear, vertical pivotal rods.
8. The leisure chair as claimed in claim 3, with the side coupling portion including a rear board, with the adjusting unit further including a pneumatic rod and a pull rod, with the rear board of the side coupling portion including a lower end having a guiding hole, with the control rod further including a push portion below the pivotal portion thereof, with the pneumatic rod including a rear end pivotably connected to the backrest and a front end pivotably connected to the seat, with the pneumatic rod further including a control cable extending through the guiding hole of the side coupling portion, with the pneumatic rod further including an end, with the pull rod including an upper end pivotably connected to the axle and a lower end coupled to the end of the pneumatic rod,
wherein when the control rod moves rearwards, the push portion actuates the pull rod to move and pull the control cable of the pneumatic rod.
9. The leisure chair as claimed in claim 8, with the adjusting unit further including a third spring having two ends respectively attached to the rear board of the side coupling portion and the pull rod, wherein when the pull rod moves, the third spring is tensioned for returning the pull rod.