JP2010192253A - Thermal switch device and superconducting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal switch device advantageous for restraining heat intrusion from outside and a superconducting device. <P>SOLUTION: The thermal switch device 400 is provided with a base body 4 forming a heat-insulating room 40, and a first member 500 arranged in the heat-insulating room 40, and a second member 600, arranged in the heat-insulating room 40 with at least a part formed of a base material having a higher coefficient of thermal expansion than the first member 500. Accordingly, as the second member 600 is cooled, a mode is changed into a first one in which a contact degree of the first member 500 and the second member 600 gets higher, directly or indirectly. As a temperature of the second member 600 is raised, the mode is changed into a second one in which a contact degree of the first member 500 and the second member 600 becomes, directly or non-directly, lower or becomes non-contacting. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a thermal switching device having a base that forms a heat insulating chamber in which heat transfer from the outside is suppressed, and a superconducting device having a thermal switching device.

  A superconducting device will be described as an example. Conventionally, a superconducting part exhibiting a superconducting phenomenon below a critical temperature, a base body having a vacuum heat insulating chamber that accommodates the superconducting part in a vacuum heat insulating state, and a superconducting part accommodated in the vacuum heat insulating chamber of the base body become below the critical temperature. There is known a superconducting device including a cooling unit for cooling the superconducting unit (Patent Documents 1 and 2). According to this, if the superconducting part is cooled below its critical temperature, the superconducting phenomenon of the superconducting part can be obtained and the electrical energy can be saved.

JP 2007-89345 A JP 2008-159828 A

  According to the superconducting device described above, even though the superconducting part is accommodated in the vacuum heat insulating chamber, there is a risk that the temperature of the superconducting part will rise due to heat penetration from the outside into the vacuum heat insulating chamber when the cooling unit is stopped. is there. In this case, depending on the degree of temperature rise of the superconducting part, when restarting the superconducting device, there is a problem that it takes time to cool the superconducting part until the superconducting part shows a superconducting state.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a thermal switch device and a superconducting device that are advantageous in suppressing heat intrusion from the outside as much as possible.

  (1) The thermal switch device of the present invention according to aspect 1 includes a base that forms a heat insulating chamber in which heat transfer from the outside is suppressed, a first member that is disposed in the heat insulating chamber of the base, and a heat insulating chamber of the base. And at least a part of the second member formed using a material having a thermal expansion coefficient larger than that of the first member as a base material. The first member and the second member are separated from each other by the cooling unit. As the temperature of the first member increases, the first member and the second member come into contact with each other directly or indirectly, and the first member and the second member increase in temperature. It is possible to switch to a second form in which the degree of contact that directly or indirectly contacts decreases or becomes non-contact. Here, the contact degree in which the first member and the second member are in direct contact means the contact degree in which the first member and the second member are in contact without an intermediate member. Moreover, the contact degree which a 1st member and a 2nd member contact indirectly means the contact degree which a 1st member and a 2nd member contact via an intermediate member.

  According to aspect 1, as the second member is cooled by the cooling unit, the amount of thermal contraction of the second member increases, so that the thermal first member and the second member contact directly or indirectly. It is switched to the first form in which the degree is increased. On the other hand, the amount of thermal expansion of the second member increases as the temperature of the second member increases, so does the contact degree between the first member and the second member directly or indirectly decrease? Or, it is switched to the second form that is non-contact.

(2) A superconducting device of the present invention according to aspect 2 includes a superconducting portion that exhibits a superconducting phenomenon below a critical temperature, a base that forms a heat insulating chamber in which heat transfer from the outside is suppressed and accommodates the superconducting portion in the heat insulating chamber, A cooling part that cools the superconducting part below the critical temperature, and a thermal switch device that is interposed between the superconducting part and the cooling part and transmits the cooling capacity of the cooling part to the superconducting part. The apparatus includes a first member disposed in the heat insulating chamber of the base member, and a second member formed in the base member of a material that is disposed in the heat insulating chamber of the base member and at least a part of which has a larger coefficient of thermal expansion than the first member. And
The first member and the second member have a first form in which the degree of contact between the first member and the second member directly or indirectly increases as the second member is cooled by the cooling unit; As the temperature of the member rises, the degree of contact with which the first member and the second member are in direct or indirect contact decreases or is switched to the second form in which they are not in contact with each other. Features.

  According to aspect 2, as the second member is cooled by the cooling unit, the amount of thermal contraction of the second member increases, and thus the contact degree at which the first member and the second member are in direct or indirect contact with each other. Is switched to the first form. In this case, the cold heat of the second member cooled by the cooling unit is efficiently transmitted from the second member to the first member, and the superconducting unit is efficiently cooled.

  On the other hand, if the cooling output of the cooling unit decreases or stops, the second member gradually increases in temperature due to heat penetration from the outside. Accordingly, the second member is thermally expanded so as to be separated from the first member. For this reason, the contact degree which a 1st member and a 2nd member contact directly or indirectly falls, or it switches to the 2nd form used as non-contact. In this case, it is suppressed that heat energy is transmitted from the second member to the superconducting portion, and the superconducting low temperature state is easily maintained.

(3) A superconducting device of the present invention according to aspect 3 includes a superconducting portion that exhibits a superconducting phenomenon below a critical temperature, a base that houses a superconducting portion in the heat insulating chamber while forming a heat insulating chamber in which heat transfer from outside is suppressed. A cooling part for cooling the superconducting part below the critical temperature, a power feeding part for feeding power to the superconducting part, and a thermal switch device interposed between the superconducting part and the feeding part to feed power from the feeding part to the superconducting part And
The thermal switch device includes a first member disposed in the heat insulating chamber of the base, and a first member formed in a base material made of a material that is disposed in the heat insulating chamber of the base and has a coefficient of thermal expansion greater than that of the first member. The first member and the second member have a degree of contact with which the first member and the second member are in direct or indirect contact with each other as the second member is cooled by the cooling unit. The 1st form which becomes high, and the 2nd form from which the contact degree which the 1st member and the 2nd member contact directly or indirectly falls or it becomes non-contact as the 2nd member raises temperature It is possible to switch to.

  According to aspect 3, since the amount of thermal contraction of the second member increases as the second member is cooled by the cooling unit, the first contact surface of the first member and the second contact surface of the second member Switching to the first form in which the degree of contact with direct or indirect contact is high. In this case, power is efficiently supplied from the power supply unit to the superconducting unit via the thermal switch device.

  On the other hand, when the cooling output of the cooling unit decreases or stops, the second member gradually increases in temperature. Accordingly, the second contact surface of the second member is thermally expanded so as to be separated from the first contact surface of the first member. For this reason, the contact degree which the 1st contact surface of a 1st member and the 2nd contact surface of a 2nd member contact directly or indirectly falls, or it switches to the 2nd form used as non-contact. In this case, the power supply energy supplied from the power supply unit to the superconducting unit is reduced or eliminated.

  According to the thermal switch device according to aspect 1, as the second member is cooled by the cooling unit, the first member and the second member are switched to the first form in which the degree of contact increases directly or indirectly. It is done. On the other hand, as the temperature of the second member increases, the contact degree in which the first member and the second member are in direct or indirect contact with each other decreases or switches to the second form in which they are not in contact with each other. It is done.

  According to the superconducting device according to aspect 2, as the second member of the thermal switch device is cooled by the cooling unit, the thermal switch device is in contact with the first member and the second member in direct or indirect contact. It is switched to the first form in which the degree is increased. In this case, the cold of the second member cooled by the cooling unit is efficiently transmitted from the second member to the first member via the thermal switch device, and the superconducting unit is efficiently cooled. On the other hand, as the second member of the thermal switch device rises in temperature, the degree of contact between the first member and the second member directly or indirectly decreases or becomes non-contact. The thermal switch device can be switched to two forms. In this case, heat is suppressed from being transmitted from the second member to the superconducting portion via the thermal switch device. Therefore, the low temperature state of the superconducting part is maintained for a long time.

  According to the superconducting device according to aspect 3, as the second member of the thermal switch device is cooled by the cooling unit, the thermal switch device is in contact with the first member and the second member in direct or indirect contact. It is switched to the first form in which the degree is increased. In this case, power is efficiently supplied from the power supply unit to the superconducting unit via the thermal switch device. On the other hand, as the temperature of the second member of the thermal switch device rises, the thermal switch device is switched to the second configuration, and the thermal switch device has a higher blocking performance. In this case, electrical energy fed from the power feeding unit to the superconducting unit via the thermal switch device can be suppressed.

It is sectional drawing which concerns on Example 1 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing which concerns on Example 1 and shows the 1st form of a thermal switch apparatus. It is sectional drawing from a different direction which concerns on Example 1 and shows the 1st form of a thermal switch apparatus. It is sectional drawing from a different direction which concerns on Example 1 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing from a different direction which concerns on Example 1 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing from a different direction which concerns on Example 2 and shows the 1st form of a thermal switch apparatus. It is sectional drawing which concerns on Example 3 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing which concerns on Example 4 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing which concerns on Example 5 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing which concerns on Example 6 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing which concerns on Example 7 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing from a different direction which concerns on Example 8 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing from a different direction which concerns on Example 9 and shows the 2nd form of a thermal switch apparatus. It is sectional drawing from a different direction which concerns on Example 10 and shows the 2nd form of a thermal switch apparatus. It is a side view which concerns on Example 11 and shows the concept of a heat switch apparatus typically. It is a side view which concerns on Example 12 and shows the concept of a thermal switch apparatus typically. It is sectional drawing which concerns on Example 13 and shows typically the concept of the superconducting motor apparatus which has a thermal switch apparatus. It is sectional drawing which concerns on Example 14 and shows typically the concept of the superconducting motor apparatus which has a thermal switch apparatus. It is a graph which shows the relationship between the thermal expansion coefficient of material, and temperature. It is a graph which shows the relationship between the thermal expansion coefficient of material, and temperature.

  At least a part of the second member is formed using a material having a larger coefficient of thermal expansion than that of the first member as a base material. The thermal expansion coefficient corresponds to the thermal contraction ratio when the temperature is lowered. Therefore, as the second member is cooled by the cooling unit, the amount of thermal contraction of the second member becomes larger than the amount of thermal contraction of the first member. Thereby, as the second member is cooled by the cooling unit, the first member and the second member are switched to the first form in which the contact degree is increased directly or indirectly. When the cooling capacity from the cooling unit decreases, the temperature of the second member rises. As the temperature of the second member rises, the amount of thermal expansion of the second member becomes larger than the thermal expansion of the first member. Thereby, it can be switched to the 2nd form from which the contact degree to which a 1st member and a 2nd member contact directly or indirectly falls or it becomes non-contact. Here, the thermal contraction and thermal expansion may be performed in the radial direction of the second member, in the axial length direction of the second member, or in both the radial direction and the axial length direction.

  According to one aspect of the present invention, preferably, the first member is connected to a cooled object, and the second member is connected to a cooling unit for exhibiting a cooling capacity for cooling the cooled object, and the cooling capacity by the cooling unit. Is cooled to form the first form. Any object may be used as the object to be cooled, and a superconducting part is exemplified. According to the present invention relating to each aspect, as the cooling unit, the cooling unit may have a structure including a refrigerator, or may be a heat transfer mechanism that transfers the low temperature from the refrigerator to the superconducting unit side. Alternatively, a mechanism that adiabatically holds a cryogenic refrigerant (for example, liquefied helium, liquefied nitrogen, or liquefied oxygen) without mounting a refrigerator may be used.

  According to one aspect of the present invention, preferably, the first member and the second member can form an energization path through which a current flows between the first member and the second member. In this case, the thermal switch can also be used as an electrical switch.

  According to one aspect of the present invention, preferably, the first member may be a male part, and the second member may be a female part surrounding the male part. A thermal switch is formed in which the male part and the female part are fitted.

  According to one aspect of the present invention, preferably, the male part forming the first member has a cylindrical outer wall surface, and the female part forming the second member faces the outer wall surface. It has a cylindrical inner wall surface, and the contact degree between the outer wall surface and the inner wall surface increases in the first form, and the contact degree between the outer wall surface and the inner wall surface decreases in the second form, or Contact. In this case, a thermal switch is formed in which the outer wall surface having the cylindrical shape of the male portion and the inner wall surface having the cylindrical shape of the female portion are fitted.

According to one aspect of the present invention, preferably, the male part forming the first member has an outer wall surface that is inclined in cross section, and the female part forming the second member is an outer wall surface in cross section. And has an inner wall surface that faces the outer wall surface and has an inclined shape that is inclined in a common direction.
In the first form, the contact degree between the outer wall surface and the inner wall surface is increased, and in the second form, the contact degree between the outer wall surface and the inner wall surface is reduced or non-contacted. In this case, a thermal switch is formed in which the outer wall surface forming the male portion and the inner wall surface forming the female portion are in contact with each other.

  According to one aspect of the present invention, preferably, at least one of the first member and the second member is formed of a plurality of layers, and among the plurality of layers, of the first member and the second member. The layer facing the other is formed using a material having a coefficient of thermal expansion that increases the degree of contact between the first member and the second member as the second member is cooled.

  When the superconducting part is cooled below the critical temperature, the superconducting part exhibits a superconducting state and can be of any shape and structure. Furthermore, the cooling unit maintains the superconducting part at a low temperature below its critical temperature in order to maintain the superconducting state of the superconducting member. The low temperature is preferably a very low temperature. Cryogenic temperature can be below the temperature range which can maintain the superconducting state of a superconducting part. Therefore, the temperature range in the cryogenic state differs depending on the critical temperature or composition of the superconducting material constituting the superconducting portion. Practically, the cryogenic state is preferably lower than the liquefaction temperature of nitrogen gas (77K) or lower. However, the cryogenic state may be 100K or less and 150K or less depending on the composition of the superconducting member. The heat insulating chamber of the substrate is preferably in a reduced pressure state such as a high vacuum state or a low vacuum state. The reduced pressure state means a pressure lower than the atmospheric pressure.

  According to an aspect of the present invention, a support member that supports at least one of the first member and the second member against gravity is provided in order to increase the coaxiality of the first member and the second member. It is preferable.

  1 to 5 show a first embodiment. The thermal switch device 400 includes a base 4 that forms a heat insulating chamber 40 (vacuum heat insulating chamber) in which heat transfer from the outside is suppressed, a first member 500 disposed in the heat insulating chamber 40 of the base 4, and a heat insulating chamber 40 of the base 4. And a second member 600 disposed on the surface. The first member 500 has a first main body 502 that has a first central axis 501 and extends in the longitudinal direction, and is formed at the distal end of the first main body 502 so that the outer diameter is larger than that of the first main body 502. The male part 503 is provided. The second member 600 includes a second body portion 602 having a second central axis 601 and extending in the longitudinal direction, and a female portion 603 having a female hole 604 for fitting the male portion 503 to the distal end portion of the second body portion 602. It has. The outer diameter of the female part 603 is larger than the outer diameter of the second main body part 602. In this case, it is possible to contribute to increasing the inner diameter of the female part 603 and the outer diameter of the male part 503.

  At least the female part 603 of the second member 600 is formed using a material having a thermal expansion coefficient larger than that of the male part 503 of the first member 500 as a base material. The thermal expansion coefficient corresponds to the thermal contraction ratio when the temperature is lowered. Therefore, the female part 603 of the second member 600 is formed using a material having a thermal contraction rate larger than that of the male part 503 of the first member 500 as a base material. The material of the first member 500 and the second member 600 is not particularly limited, and any of metal, ceramics, resin, and reinforcing material reinforced resin may be used. The magnitude relationship of the thermal expansion coefficient (thermal contraction ratio) described above may be used. It is necessary to have. When the reinforcing material is a fiber, the thermal expansion coefficient (thermal contraction coefficient) in the direction in which the fiber extends can often be adjusted.

  As shown in FIG. 1, the outer wall surface 505 (first contact surface) of the male portion 503 forming the first member 500 has a straight cylindrical shape with a substantially uniform outer diameter along the axial length direction. . The inner wall surface 605 (second contact surface) of the female portion 603 forming the second member 600 faces the outer wall surface 505 of the male portion 503 and has a straight shape with a substantially uniform inner diameter along the axial length direction. It has a cylindrical shape.

  When the second member 600 is cooled and cooled by the cooling unit 3E or the like, the thermal contraction amount of the female portion 603 of the second member 600 is the male portion 503 of the first member 500 in the radially inward direction (arrow DA2 direction). The amount of heat shrinkage is relatively larger. For this reason, in the thermal switch device 400, the degree of contact with which the inner wall surface 605 of the female portion 603 of the second member 600 contacts the outer wall surface 505 of the male portion 503 of the first member 500 is increased, and the heat switch device 400 is switched to the first form. According to the first embodiment, as shown in FIG. 3, it is preferable that the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 are in contact with the entire circumference. This is because heat or cold mobility between the second member 600 and the first member 500 constituting the thermal switch device 400 is ensured satisfactorily. In addition, when the thermal switch device 400 forms an energization path, the electrical conductivity between the second member 600 and the first member 500 is ensured.

  On the other hand, when the temperature of the second member 600 is increased, the thermal expansion amount of the female portion 603 of the second member 600 is larger than the thermal expansion amount of the first member 500 in the radially outward direction (the arrow DB2 direction). It becomes relatively large. For this reason, the inner wall surface 605 of the female portion 603 of the second member 600 is separated from the outer wall surface 505 of the male portion 503 of the first member 500. Therefore, the thermal switch device 400 has a second form in which the contact degree between the inner wall surface 605 and the outer wall surface 505 decreases or the inner wall surface 605 and the outer wall surface 505 are not in contact with each other. Can be switched. According to the second embodiment, as shown in FIG. 4, the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 are uniformly spaced all around, and a gap 507 having a uniform gap width is formed inside. It is preferable to form the entire circumference between the wall surface 605 and the outer wall surface 505. In this case, the heat penetration amount from the female portion 603 of the second member 600 into the male portion 503 of the first member 500 is effectively suppressed by the gap 507, and the temperature rise of the first member 500 is suppressed. When the thermal switch device 400 forms an energization path through which current flows from the second member 600 to the first member 500, the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 are uniform over the entire circumference. It is preferable that they are separated from each other. This is because the mobility of heat or cold between the second member 600 and the first member 500 is suppressed. In addition, when the thermal switch device 400 forms an energization path, the electrical conductivity between the second member 600 and the first member 500 is suppressed.

  However, also in the second embodiment, when the thermal switch device 400 does not form an energization path, the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 are almost separated as shown in FIG. However, only a part of the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 may be in contact with each other. Even in this case, since the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 are almost separated from each other, in the thermal switch device 400, the male portion of the first member 500 is separated from the female portion 603 of the second member 600. The amount of heat entering the portion 503 is suppressed. In addition, although the temperature range where the favorable clearance gap 507 is obtained changes also with the use of the thermal switch apparatus 400, use environment, a kind, and the base material of the 1st member 500 and the 2nd member 600, it is higher than -50 degreeC. Examples include a temperature region, a temperature region higher than −20 ° C., a temperature region higher than −10 ° C., a temperature region higher than 0 ° C., and a temperature region in a normal temperature region. However, it is not limited to these.

  In addition, it is preferable that the material of the 1st member 500 and the 2nd member 600 has favorable heat conductivity and / or electroconductivity. Therefore, the base material of the female portion 603 of the second member 600 is exemplified by aluminum or an aluminum alloy. Examples of the base material of the male part 503 of the first member 500 include copper and a copper alloy.

  FIG. 6 shows a second embodiment. Although the present embodiment has the same configuration and the same function and effect as the first embodiment, the male portion 503 of the first member 500 has a polygonal shape (hexagonal shape) in a cross section orthogonal to the first central axis 501. . When the second member 600 is cooled, the first form in which the inner wall surface 605 forming the cylindrical shape of the female portion 603 of the second member 600 is in contact with the corner portion 503x of the male portion 503 of the first member 500 is increased. The thermal switch device 400 is switched. According to the second form, the inner wall surface 605 forming the cylindrical shape of the female portion 603 of the second member 600 is separated from the corner portion 503x of the male portion 503 of the first member 500.

  FIG. 7 shows a third embodiment. The present embodiment has the same configuration and the same operational effects as the first embodiment. The outer wall surface 505 of the male part 503 forming the first member 500 is inclined in a cross section passing through the first central axis 501 along the first central axis 501. The inner wall surface 605 of the female portion 603 that forms the second member 600 has the same cross section and is inclined in the same direction as the outer wall surface 505, and faces the outer wall surface 505 of the male portion 503. Specifically, as shown in FIG. 7, the outer wall surface 505 of the male portion 503 is a conical wall surface whose outer diameter decreases toward the distal end surface 503 e of the male portion 503. The inner wall surface 605 of the female portion 603 is a conical wall surface whose inner diameter increases toward the tip end surface 603e of the female portion 603. In the second form, a gap 507 is formed between the inner wall surface 605 and the outer wall surface 505, and heat intrusion from the second member 600 to the first member 500 is suppressed.

  As shown in FIG. 7, the 1st support member 540 which supports the male part 503 of the 1st member 500 with respect to gravity is provided. A second support member 640 that supports the female portion 603 of the second member 600 against gravity is provided. Thereby, the drooping of the first central axis 501 of the first member 500 and the drooping of the second central axis 601 of the second member 600 are suppressed, so that the coaxiality of the axes 501 and 601 becomes high at a microscopic level, and the gap It is advantageous to make the gap width of 507 uniform over the entire circumference. The first support member 540 and the second support member 640 are preferably formed of a material with low thermal conductivity. When the thermal switch device exhibits electrical conductivity, the first support member 540 and the second support member 640 are preferably formed of a material having high electrical resistance or a material having electrical insulation.

  FIG. 8 shows a fourth embodiment. The present embodiment has the same configuration and the same operational effects as the first embodiment. The outer wall surface 505 of the male part 503 forming the first member 500 is inclined in a cross section passing through the first central axis 501 along the first central axis 501. The inner wall surface 605 of the female portion 603 that forms the second member 600 has an inclined shape that is inclined in the same section as the outer wall surface 505 and faces the outer wall surface 505. Specifically, as illustrated in FIG. 8, the outer wall surface 505 of the male part 503 is a conical wall surface whose outer diameter increases toward the distal end surface 503 e of the male part 503. The inner wall surface 605 of the female portion 603 is a conical wall surface whose inner diameter decreases toward the distal end surface 603e of the female portion 603. The cone angle of the inner wall surface 605 is preferably substantially the same as the cone angle of the outer wall surface 505.

  In FIG. 8, when the second member 600 is cooled and cooled by the cooling unit 3E or the like, the amount of thermal contraction of the female portion 603 of the second member 600 in the radial direction (arrow DA2 direction) is the first member 500. The amount of heat shrinkage is relatively larger. For this reason, the contact degree which the inner wall surface 605 of the female part 603 of the 2nd member 600 contacts with the outer wall surface 505 of the male part 503 of the 1st member 500 becomes high, and it switches to a 1st form. According to the first embodiment, it is preferable that the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 are in contact with the entire circumference. This is because heat or cold mobility between the second member 600 and the first member 500 is ensured.

  As described above, when the thermal switch device 400 is switched to the first mode, the second member 600 is cooled by the cooling unit 3E or the like. At this time, the second member 600 is thermally contracted not only in the radial direction (arrow DA2 direction) but also in the axial length direction (arrow LA2 direction), and the length of the second member 600 is contracted. The female part 603 is mutated in the direction of the arrow LA2. As a result, according to the first embodiment, the contact degree at which the inner wall surface 605 of the female portion 603 of the second member 600 contacts the outer wall surface 505 of the male portion 503 of the first member 500 is further increased.

  Thus, when the contact degree of the thermal switch device 400 becomes high, the cold heat from the second member 600 is transmitted to the first member 500 through the contact. For this reason, the first member 500 is cooled and cooled. At this time, the first member 500 is thermally contracted not only in the radial direction (arrow DA1 direction) but also in the axial length direction (arrow LA1 direction), the length of the first member 500 is contracted, and the male portion 503 is moved to the arrow. Displacement in the direction of LA1. As a result, there is an advantage that the contact degree at which the inner wall surface 605 of the female portion 603 of the second member 600 contacts the outer wall surface 505 of the male portion 503 of the first member 500 is further increased. As a result, the mobility of heat or cold between the second member 600 and the first member 500 is further enhanced. Further, when the thermal switch device 400 forms an energization path, the electrical conductivity between the second member 600 and the first member 500 is enhanced.

  On the other hand, when the cooling heat transmitted from the cooling unit 3E to the second member 600 decreases, the temperature of the second member 600 is gradually increased. Then, in the radially outward direction (arrow DB2 direction), the thermal expansion amount of the female portion 603 of the second member 600 is relatively larger than the thermal expansion amount of the male portion 503 of the first member 500. Therefore, as shown in FIG. 8, the inner wall surface 605 of the female portion 603 of the second member 600 is separated from the outer wall surface 505 of the male portion 503 of the first member 500, and a gap 507 is formed. Therefore, the degree of contact between the inner wall surface 605 and the outer wall surface 505 decreases, or the inner wall surface 605 and the outer wall surface 505 are not in contact with each other, and the thermal switch device 400 is switched to the second form.

  Thus, when the heat switch apparatus 400 is switched to a 2nd form, the 2nd member 600 is heated up. At this time, the second member 600 is thermally expanded not only in the radially outward direction (arrow DB2 direction) but also in the axial length direction (arrow LB2 direction), and the length of the second member 600 is extended. As a result, according to the second embodiment, since the inner wall surface 605 of the female portion 603 of the second member 600 is further separated from the outer wall surface 505 of the male portion 503 of the first member 500, the gap width of the gap 507 increases. The degree of non-contact is further increased.

  As described above, when the temperature of the first member 500 is raised when the thermal switch device 400 is switched to the second configuration, the first member 500 is not only in the radially outward direction (arrow DB1 direction) but also in the axial length direction (arrow LB1 direction). ), The length of the first member 500 extends. As a result, according to the second embodiment, the inner wall surface 605 of the female portion 603 of the second member 600 and the outer wall surface 505 of the male portion 503 of the first member 500 are further displaced in a direction away from each other. For this reason, the gap width of the gap 507 is further increased, and an advantage that the non-contact degree between the first member 500 and the second member 600 is further increased can be obtained. In this case, the mobility of heat or cold between the second member 600 and the first member 500 is suppressed. Further, when the thermal switch device 400 forms an energization path, the electrical conductivity between the second member 600 and the first member 500 is suppressed.

  FIG. 9 shows a fifth embodiment. This embodiment has the same configuration and the same function and effect as the embodiment shown in FIG. However, the 2nd main-body part 602 of the 2nd member 600 has the curved part 609 (expansion-absorption absorption part in an axial length direction). When the second member 600 is cooled down by the cooling unit 3E and the second member 600 is cooled down and switched to the first mode, the second member 600 is cooled. At this time, the second member 600 is thermally contracted not only in the radially inward direction (arrow DA2 direction) but also in the axial length direction (arrow LA2 direction), and the length of the second member 600 contracts. As a result, when the amount of thermal contraction in the axial length direction (arrow LA2 direction) is large, the inner wall surface 605 of the female portion 603 of the second member 600 is the first member depending on the base material of the first member 500 and the second member 600. There is a risk of excessive contact with the outer wall surface 505 of the male portion 503 of 500, and excessive pulling of the first member 500 in the length direction thereof.

  In this regard, according to the present embodiment shown in FIG. 9, the curved portion 609 is formed in the second main body portion 602 of the second member 600, and the curved portion 609 is excessive in the axial length direction (arrow LA2 direction). Absorbs heat shrinkage. For this reason, the possibility that the inner wall surface 605 of the female portion 603 of the second member 600 is excessively in contact with the outer wall surface 505 of the male portion 503 of the first member 500 is reduced.

  FIG. 10 shows a sixth embodiment. In this embodiment, the stretchability of the second member 600 in the length direction is used. When the temperature of the second member 600 is increased, the second contact surface 605K of the second member 600 and the first contact surface 505K of the first member 500 form a gap 507 in the direction in which the axes 501 and 601 extend. Facing each other. Here, the first contact surface 505K and the second contact surface 605K are perpendicular to the central axes 501 and 601.

  In contrast, when the temperature of the second member 600 is decreased, for example, when the second member 600 is cooled, the second member 600 is heated not only in the radially inward direction but also in the axial length direction (arrow LA2 direction). As a result, the length of the second member 600 contracts. As a result, when the amount of thermal contraction in the axial length direction is large, the second member 600 is pulled in the direction of the arrow LA2, and the second contact surface 605K of the second member 600 contacts the first contact surface 505K of the first member 500. , Switched to the first form.

  In contrast, when the cooling operation of the cooling unit 3E is stopped, the temperature of the second member 600 is gradually increased. At this time, the second member 600 is thermally expanded not only in the radially outward direction but also in the axial length direction (the direction of the arrow LB2), and the length of the second member 600 is expanded. As a result, the second member 600 extends in the direction of the arrow LB2, the second contact surface 605K is separated from the first contact surface 505K, a gap 507 is formed, and the second form is switched.

  Here, the amount of expansion / contraction in the length direction of the second member 600 is larger than the amount of expansion / contraction in the radial direction of the second member 600. For this reason, even if the gap width of the gap 507 is increased, good contact between the second contact surface 605K and the first contact surface 505K is ensured during thermal contraction. In addition, the coating layer 508 may be coat | covered by the outer peripheral wall surface of the 1st member 500 as needed. The covering layer 508 is preferably formed of a high electrical insulating material and / or a material having high thermal insulating properties (for example, glass-based or ceramic-based).

  FIG. 11 shows a seventh embodiment. In this embodiment, the stretchability of the second member 600 in the length direction is used. The outer wall surface 505 (first contact surface) of the male part 503 forming the first member 500 is inclined in a cross section passing through the first central axis 501 along the first central axis 501. The second member 600 has a female portion 603 extending in a direction intersecting with the second central axis 601 thereof. The inner wall surface 605 (second contact surface) of the female portion 603 has an inclined shape that is inclined in the same section as the outer wall surface 505 and faces the outer wall surface 505. Since the female hole 604 penetrates in the direction of the second central axis 601, it is easy to process the inner wall surface 605 that forms the conical shape of the female hole 604.

  Specifically, as illustrated in FIG. 11, the outer wall surface 505 of the male portion 503 is a conical wall surface whose outer diameter increases toward the distal end surface 503 e of the male portion 503. The inner wall surface 605 of the female portion 603 is a conical wall surface whose inner diameter decreases toward the distal end surface 603e of the female portion 603. The cone angle of the inner wall surface 605 is preferably substantially the same as the cone angle of the outer wall surface 505. The central axes 501 and 601 are shifted by ΔME in the radial direction.

  When the second member 600 is cooled and cooled by the cooling unit 3E or the like, the thermal switch device 400 is switched to the first form in the radial direction (arrow DA2 direction). When the second member 600 is thus cooled, the second member 600 is thermally contracted not only in the radial direction (arrow DA2 direction) but also in the axial length direction (arrow LA2 direction). Is shrunk. As a result, the female part 603 is displaced in the direction of the arrow LA2. Accordingly, the contact degree at which the inner wall surface 605 of the female portion 603 of the second member 600 contacts the outer wall surface 505 of the male portion 503 of the first member 500 is further increased. In this case, the mobility of heat or cold between the second member 600 and the first member 500 is enhanced. Further, when the thermal switch device 400 forms an energization path, the electrical conductivity between the second member 600 and the first member 500 is enhanced.

  On the other hand, when the cooling heat transmitted from the cooling unit 3E to the second member 600 decreases, the temperature of the second member 600 is gradually increased. Then, in the radially outward direction (arrow DB2 direction) and the axial length direction (arrow LB2 direction), the thermal expansion amount of the female portion 603 of the second member 600 is relative to the thermal expansion amount of the male portion 503 of the first member 500. Become bigger. For this reason, as shown in FIG. 11, the female part 603 is displaced in the direction of the arrow LB2. Accordingly, the inner wall surface 605 of the female portion 603 of the second member 600 is separated from the outer wall surface 505 of the male portion 503 of the first member 500. For this reason, the contact degree in which the inner wall surface 605 and the outer wall surface 505 contact each other decreases, or the inner wall surface 605 and the outer wall surface 505 are switched to the second form in which they are not in contact with each other.

  FIG. 12 shows an eighth embodiment. The present embodiment has the same configuration and the same operational effects as the respective embodiments. As shown in FIG. 12, the female portion 603 of the second member 600 is formed of a plurality of layers, the second outer layer 621 facing away from the male portion 503 of the first member 500, and the male portion of the first member 500. And a second inner layer 622 facing the outer wall surface 505 of 503. The base material of the second inner layer 622 is selected so that the thermal expansion coefficient of the second inner layer 622 is larger than the thermal expansion coefficient of the second outer layer 621 and the thermal expansion coefficient of the male part 503 of the first member 500. . Accordingly, when the temperature is lowered, the thermal contraction rate of the second inner layer 622 is larger than the thermal contraction rate of the second outer layer 621 and the thermal contraction rate of the male portion 503 of the first member 500. The material is selected. Here, generally, a material having a thermal expansion coefficient larger than that of a normal material is generally high in cost. However, according to this embodiment, the female portion 603 of the second member 600 is formed of a plurality of layers of the second outer layer 621 and the second inner layer 622. For this reason, since only the second inner layer 622 needs to be a material having a higher coefficient of thermal expansion than that of the normal material, the thermal switching device 400 can realize the switching action of the first and second modes of the thermal switching device 400. It is advantageous to reduce the manufacturing cost of 400.

  FIG. 13 shows a ninth embodiment. The present embodiment has the same configuration and the same operational effects as the respective embodiments. As shown in FIG. 13, the male part 503 of the first member 500 is formed of a plurality of layers, and the first outer layer 521 facing the inner wall surface 605 of the female part 603 of the second member 600 and the second member 600. The first inner layer 522 facing away from the inner wall surface 605 of the female portion 603 is provided. The base material of the first outer layer 521 is selected so that the thermal expansion coefficient of the first outer layer 521 is smaller than the thermal expansion coefficient of the first inner layer 522 and the thermal expansion coefficient of the female portion 603 of the second member 600. . Accordingly, when the temperature is lowered, the thermal contraction rate of the first outer layer 521 is smaller than the thermal contraction rate of the first inner layer 522 and the thermal contraction rate of the female portion 603 of the second member 600. The material is selected. In general, a material having a coefficient of thermal expansion smaller than that of a normal material is expensive. However, according to the present embodiment, as shown in FIG. 12, since the male portion 503 of the first member 500 is formed of a plurality of layers of the first outer layer 521 and the first inner layer 522, the coefficient of thermal expansion is small. The only expensive material is the first outer layer 521. For this reason, it is advantageous to reduce the manufacturing cost of the thermal switching device 400 while realizing the switching action of the first and second configurations of the thermal switching device 400.

  FIG. 14 shows a tenth embodiment. The present embodiment has the same configuration and the same operational effects as the respective embodiments. As shown in FIG. 14, the female portion 603 of the second member 600 is formed of a plurality of layers, and the cylindrical second outer layer 621 facing the male portion 503 of the first member 500 and the first member 500. A cylindrical second inner layer 622 facing the male portion 503, and a cylindrical second intermediate layer 623 interposed between the second inner layer 622 and the second outer layer 621. The thermal expansion coefficient of the second inner layer 622 facing the male part 503 is larger than the thermal expansion coefficient of the second outer layer 621 and the thermal expansion coefficient of the male part 503 of the first member 500. The material is selected. Accordingly, when the temperature is lowered, the thermal contraction rate of the second inner layer 622 is larger than the thermal contraction rate of the second outer layer 621 and the thermal contraction rate of the male portion 503 of the first member 500. The material is selected. Here, a material having a larger coefficient of thermal expansion than a normal material is generally expensive. However, according to the present embodiment, since the second member 600 includes the second outer layer 621 and the second inner layer 622, only the second inner layer 622 needs to be a material having a large coefficient of thermal expansion (thermal contraction rate) and high cost. . For this reason, it is advantageous to reduce the manufacturing cost of the thermal switching device 400 while realizing the switching action of the first and second configurations of the thermal switching device 400.

  Further, the base material is selected so that the second intermediate layer 623 has an intermediate thermal expansion coefficient between the second outer layer 621 and the second inner layer 622. When the female portion 603 of the second member 600 is thermally expanded in the radially outward direction or when thermally contracted in the radially inward direction, the advantage that the second member 600 can be favorably displaced is obtained. An intermediate layer may be formed on the male portion 503.

  FIG. 15 shows Example 11. The present embodiment has the same configuration and the same operational effects as the respective embodiments. As shown in FIG. 15, the apparatus forms an object 700 to be cooled, which is preferably maintained at a low temperature, and a vacuum heat insulating chamber 40 (heat insulating chamber) in which heat transfer from the outside is suppressed, and is cooled in the vacuum heat insulating chamber 40. The body 4 that accommodates the body 700, the cooling unit 3E for cooling the body 700 to be cooled, and the cooling heat (cooling output) of the cooling unit 3E interposed between the body 700 and the cooling unit 3E. And a thermal switch device 400 to be transmitted to 700. The thermal switch device 400 is disposed in the vacuum heat insulation chamber 40 of the base body 4 and has a first member 500 having a male part 503, and the heat conductivity having a female part 603 disposed in the vacuum heat insulation chamber 40 of the base body 4. The 2nd member 600 which has these. The female part 603 is formed using a material having thermal conductivity and a thermal expansion coefficient (thermal contraction rate) larger than that of the male part 503 of the first member 500 in the radial direction.

  Here, when the compressor of the cooling unit 3E is turned on and the cooling unit 3E generates a refrigeration output, the second member 600 is cooled in the vacuum heat insulating chamber 40 by the cold heat of the cooling unit 3E. Here, when the second member 600 is cooled to an extremely low temperature (low temperature), the amount of thermal contraction of the female portion 603 of the second member 600 is larger than the amount of thermal contraction of the male portion 503 of the first member 500 in the radial direction. Is also relatively large. For this reason, the contact degree with which the inner wall surface 605 of the female part 603 of the 2nd member 600 contacts the outer wall surface 505 of the male part 503 of the 1st member 500 becomes high, and the thermal switch apparatus 400 is switched to a 1st form. According to such a 1st form, when it considers transmitting cold heat of the cooling part 3E to the to-be-cooled body 700 effectively, the inner wall surface 605 of the female part 603 of the 2nd member 600 and the male of the 1st member 500 It is preferable that the outer wall surface 505 of the part 503 contacts the entire circumference.

  On the other hand, when the compressor of the cooling unit 3E is turned off and the cooling heat transmitted from the cooling unit 3E to the second member 600 is reduced, the second member 600 is also kept in the heat insulating state in the vacuum heat insulating chamber 40. Regardless, the temperature of the second member 600 is gradually increased. Then, in the radially outward direction, the thermal expansion amount of the female portion 603 of the second member 600 is relatively larger than the thermal expansion amount of the male portion 503 of the first member 500. For this reason, the inner wall surface 605 of the female portion 603 of the second member 600 is separated from the outer wall surface 505 of the male portion 503 of the first member 500, and the degree of contact between the inner wall surface 605 and the outer wall surface 505 decreases. Alternatively, the inner wall surface 605 and the outer wall surface 505 are not in contact with each other. As a result, the thermal switch device 400 is switched to the second configuration. As a result, the amount of heat penetration from the female part 603 of the second member 600 toward the male part 503 of the first member 500 is suppressed. The low temperature state of the cooled object 700 that is thermally connected to the first member 500 is well maintained for a long time.

  According to such a 2nd form, the inner wall surface 605 of the female part 603 of the 2nd member 600 and the outer wall surface 505 of the male part 503 of the 1st member 500 are uniformly spaced on the whole periphery, and uniform gap width It is preferable that the gap 507 having the In this case, the amount of heat penetration from the female part 603 of the second member 600 toward the male part 503 of the first member 500 is effectively suppressed. However, even in the second embodiment, although the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 are almost separated from each other, only a part of the inner wall surface 605 and the male portion 503 of the female portion 603 is outside. The wall surface 505 may be in contact. Also in this case, since the inner wall surface 605 of the female part 603 and the outer wall surface 505 of the male part 503 are almost separated from each other, heat intrusion from the female part 603 of the second member 600 to the male part 503 of the first member 500 is performed. The amount is limited.

  FIG. 16 shows a twelfth embodiment. This example has the same configuration and the same effect as the example 11 shown in FIG. However, as shown in FIG. 16, a plurality (two) of thermal switching devices 400 are arranged in series between the cooled object 700 and the cooling unit 3E. Here, one thermal switch device 400 suppresses the amount of heat intrusion from the female portion 603 of the second member 600 to the male portion 503 of the first member 500. Since a plurality of thermal switch devices 400 are arranged in series, the amount of heat intrusion from the female portion 603 of the second member 600 to the male portion 503 of the first member 500 is further suppressed, and the heat to the cooled object 700 is reduced. The amount of intrusion is further suppressed.

  Note that three or four thermal switch devices 400 may be arranged in series, or more. In this case, since each thermal switch device 400 functions to block heat penetration, the amount of heat penetration from the female portion 603 of the second member 600 to the male portion 503 of the first member 500 is further suppressed.

  FIG. 17 shows a thirteenth embodiment. The present embodiment is merely an example of the present invention, and is not limited to this. The present embodiment is applied to a superconducting motor device as an example of a magnetic field generator that is a typical example of a superconducting device. FIG. 17 shows a superconducting motor device 1 according to this example. The superconducting motor device 1 can be used for in-vehicle use, stationary use, industrial use, and the like, and includes a superconducting motor 2 that functions as a magnetic field generation unit, a cryogenic generation unit 3 that functions as a cooling unit, and a container-shaped substrate. 4.

  Here, the superconducting motor 2 forms a motor that supplies three-phase alternating currents having phases different from each other by 120 degrees. The superconducting motor 2 includes a cylindrical stator 20 that makes a round around the axis P <b> 1 thereof, and a rotor 27 that functions as a movable element that can rotate with respect to the stator 20. The rotor 27 includes a rotating shaft 28 that is rotatably supported around the axis P1 of the superconducting motor 2, and a plurality of permanent magnets arranged on the outer peripheral portion of the rotating shaft 28 at intervals in the circumferential direction thereof. Part 29. The permanent magnet portion 29 can be formed of a known permanent magnet.

  The stator 20 functions as a cylindrical fixed iron core 21 made of a material having high magnetic permeability that functions as a magnetically permeable yoke, and a superconducting part that is wound and held around a tooth portion 210 that constitutes the fixed iron core 21. And a superconducting coil 22. A plurality of teeth 210 are arranged at equal intervals in the radial direction. In FIG. 1, in the superconducting coil 22, the coil wire 22 x and the coil wire 22 y sandwiching the tooth portion 210 flow currents in opposite directions.

  The superconducting coil 22 functioning as a superconducting part is divided into three parts so that a three-phase alternating current can be passed. Superconducting coil 22 is made of a known superconducting material. The superconducting coil 22 is disposed in a throttle groove 21 a formed in the inner peripheral portion of the fixed iron core 21. When a three-phase alternating current flows through the superconducting coil 22, a rotating magnetic field that rotates around the stator 20, that is, around the axis P1 is generated. The rotor 27 is rotated around its axis P1 by the rotating magnetic field, and a motor function is obtained.

  The cryogenic temperature generator 3 maintains the superconducting coil 22 at a cryogenic temperature in order to maintain the superconducting state of the superconducting coil 22. The cryogenic temperature range obtained by the cryogenic generator 3 is selected according to the material of the superconducting material constituting the superconducting coil 22, but can be made lower than the nitrogen liquefaction temperature, for example, 0 to 150 K, especially 1 -100K, 1-80K. However, it is not limited to these depending on the material of the superconducting material. The cryogenic temperature generation unit 3 includes a refrigerator 30 that generates an extremely low temperature in the cold head 32. Examples of the refrigerator 30 include known refrigerators such as a pulse tube refrigerator, a Stirling refrigerator, a Gifod McMahon refrigerator, a Solvay refrigerator, a Villemeier refrigerator, and the like.

  A heat conducting portion 33 is provided that uses a heat transfer material as a base material that connects the cold head 32 of the refrigerator 30 and the fixed iron core 21 of the stator 20 of the superconducting motor 2 so as to allow heat transfer. The heat conducting unit 33 has a head 33 h that is cooled to a low temperature by the cold head 32. The heat conducting portion 33 is formed of a material having high heat conductivity (for example, copper, copper alloy, aluminum, aluminum alloy) or the like.

As shown in FIG. 17, the substrate 4 has a container shape, and forms a vacuum heat insulating chamber 40 that functions as a vacuum heat insulating chamber that functions as a heat insulating chamber 40 that insulates the superconducting coil 22. Vacuum is meant to be a reduced pressure enough to maintain sufficient Naru insulation, for example, ¹⁰ -1 Pa or ^less, can be ¹⁰ -2 Pa or less, or ¹⁰ -5 Pa or less. The vacuum heat insulating chamber 40 of the base 4 is an outer vacuum heat insulating chamber 41 (for example, surrounding the outer peripheral side (outside) of the superconducting coil 22 wound around the stator 20 together with the outer peripheral side (outer side) of the stator 20. 10 ⁻¹ Pa or less, 10 ⁻² Pa or less) and an inner vacuum heat insulation chamber 42 (pressure: 10 ⁻¹ ) surrounding the inner peripheral side (inner side) of the superconducting coil 22 together with the inner peripheral side (inner side) of the stator 20. Pa or less, 10 ⁻² Pa or less). The vacuum heat insulation chamber 40 is maintained in a high vacuum state (a state where the pressure is reduced from the atmospheric pressure) at the time of shipment, but it is preferable that the vacuum heat insulation chamber 40 be maintained in a high vacuum state for a long time by maintenance or the like.

  In this case, since the superconducting coil 22 is surrounded by the outer vacuum heat insulating chamber 41 and the inner vacuum heat insulating chamber 42, the superconducting coil 22 is maintained in an extremely low temperature state, and thus the superconducting state is maintained. As shown in FIG. 17, the outer vacuum heat insulating chamber 41 includes a first heat insulating chamber portion 41 a that surrounds the outer peripheral portion of the stator 20, and a second outer portion that surrounds the outside of the head portion 33 h and the cold head 32 of the heat conducting portion 33. And a heat insulating chamber portion 41c. The second heat insulating chamber portion 41c surrounds the heat conducting section 33 and the cold head 32, and maintains these low temperatures.

  As shown in FIG. 17, the base 4 includes a first container 43, a second container 44, a third container 45, and a fourth container 46 that are coaxially arranged from the outside to the inside. The first container 43 and the second container 44 face each other in the radial direction of the fixed iron core 21 so as to form the outer vacuum heat insulation chamber 41. The third container 45 and the fourth container 46 face each other in the radial direction of the fixed iron core 21 so as to form the inner vacuum heat insulation chamber 42.

  A rotor 27 is rotatably disposed in a cylindrical space 47 defined by the fourth container 46. The space 47 communicates with the atmosphere. The rotor 27 is connected to a rotary operating body. In addition, when the superconducting motor device 1 is mounted on a vehicle such as an automobile, the rotary operating body is exemplified by a traveling wheel or the like. Therefore, when the rotor 27 rotates, the wheel can rotate.

  As shown in FIG. 17, the first container 43 includes a cylindrical first surrounding portion 431 that surrounds the outer peripheral portion of the superconducting motor 2, and a second surrounding portion 434 that covers the cold head 32 and the heat conducting portion 33. In order to attach a cylindrical guide portion 433 that forms a guide chamber 432 that guides a three-phase current introduction line 56 that supplies power to the superconducting coil 22, and a flange 30c of the compressor 30a that compresses the refrigerant gas of the refrigerator 30. Mounting flange portion 435. As shown in FIG. 17, the guide portion 433 protrudes from the second surrounding portion 434 that surrounds the superconducting motor 2 in the first container 43. In addition, although the outer side of the 1st container 43 can be open | released to air | atmosphere, it is not limited to this. The outside of the first container 43 may be covered with a heat insulating material.

  As a material constituting the first container 43, it is preferable that the leakage magnetic flux is not transmitted or is difficult to transmit and has strength. Examples of such a material include non-magnetic metal materials having a low magnetic permeability (for example, alloy steel such as austenitic stainless steel). As a material constituting the second container 44, the third container 45, and the fourth container 46, a material having a high electric resistance is preferable in order to suppress an eddy current based on a change in magnetic flux. Examples of such materials include resins, reinforcing material reinforced resins, ceramics, and the like. Examples of the reinforcing material of the reinforcing material-reinforced resin include inorganic substances such as glass and ceramics. The reinforcing material is preferably a reinforcing fiber, and examples thereof include inorganic fibers such as glass fibers and ceramic fibers. The resin may be either a thermosetting resin or a thermoplastic resin.

  As shown in FIG. 17, a plate-like fixing portion 70 is fixed to the distal end portion of a cylindrical guide portion 433 projecting partially from the first container 43. The fixing portion 70 is preferably formed of a material that is electrically and thermally highly insulating and / or a material that hardly transmits magnetic flux. For example, nonmagnetic and paramagnetic metal materials (for example, austenite type), resin, fiber reinforced resin, and ceramics having low magnetic permeability are exemplified. Since the guide chamber 432 communicates with the outer vacuum heat insulation chamber 41, the guide chamber 432 is in a vacuum heat insulation state (reduced pressure heat insulation state) and can exhibit a heat insulation function. Therefore, the electrode 5 functioning as a power feeding unit is easily maintained as low a temperature as possible.

  As shown in FIG. 17, the plurality (three) of electrodes 5 are electrically connected to the superconducting coil 22 via current introduction wires 56, and are terminals based on a conductive material that supplies power to the superconducting coil 22. It is. The electrode 5 has a protruding portion 55 that protrudes from the fixed portion 70 in a direction away from the fixed portion 70. The electrode 5 is held in a fixed state by the fixing portion 70 at the distal end portion of the guide portion 433 of the first container 43. The material for forming the electrode 5 is not particularly limited as long as it is a conductive material, and examples thereof include copper, copper alloy, aluminum, aluminum alloy, iron, iron alloy, silver, and silver alloy, but are not limited thereto. What is necessary is just to have electroconductivity instead of what.

  When the superconducting motor 2 is driven, a three-phase alternating current is supplied to the electrode 5 connected to an external power source when a changeover switch (not shown) is turned on. As a result, power is supplied to the superconducting coil 22. As a result, a rotating magnetic field is generated around the axis P1 in the superconducting motor 2, and the rotor 27 rotates around the axis P1. Thereby, the superconducting motor 2 is driven. Here, the magnetic flux passes through the third container 45, the inner vacuum heat insulation chamber 42, and the fourth container 46, causes the permanent magnet portion 29 of the rotor 27 to be attracted and repelled, and the rotor 27 rotates. Thus, when the superconducting motor 2 is rotationally driven, the superconducting coil 22 and the fixed iron core 21 are satisfactorily brought into a cryogenic state through the cold head 32 and the heat conducting unit 33 due to the cryogenic temperature generated by the cryogenic temperature generating unit 3. Maintained. Therefore, the superconducting coil 22 is well maintained below its critical temperature, and the superconducting motor 2 is driven to rotate well. Since the electric resistance of the superconducting coil 22 is 0 or extremely low, the output of the superconducting motor 20 is high.

  Now, according to the present embodiment, as shown in FIG. 17, the thermal switching device 400 </ b> W is disposed in each of the three-phase current introduction wires 56 that connect the electrode 5 and the superconducting coil 22. The thermal switch device 400W has any one of the structures described above. When the inside of the vacuum heat insulating chamber 40 (including the guide chamber 432) is cooled to a very low temperature state by the cryogenic temperature generation unit 3, the second member 600 of the thermal switch device 400W is cooled to a very low temperature state. Then, the thermal switch device 400W is switched to the first form and becomes electrically conductive. In this case, power is supplied from the electrode 5 toward the superconducting coil 22 via the current introduction line 56 and the thermal switch device 400W.

  On the other hand, when the superconducting motor 2 is stopped, the switching element 58 connected to the electrode 5 is turned off, power supply to the electrode 5 is stopped, and the refrigerator 30 of the cryogenic temperature generating unit 3 is turned off. In this case, external heat easily enters the superconducting coil 22 from the electrode 5 via the current introduction line 56 and the thermal switch device 400W. Therefore, the temperature of the thermal switch device 400W is gradually increased to be in the second form. Thus, if the thermal switch apparatus 400W becomes a 2nd form, as mentioned above, the inside of the thermal switch apparatus 400W will be interrupted | blocked thermally and electrically. For this reason, it is suppressed that external heat enters the superconducting coil 22 from the electrode 5 via the current introduction line 56 and the thermal switch device 400W. Accordingly, the superconducting coil 22 can be favorably maintained at a low temperature for a long time. Therefore, an advantage that is advantageous when the superconducting motor device is restarted can be obtained.

  FIG. 18 shows a fourteenth embodiment. This embodiment has basically the same configuration and the same function and effect as the thirteenth embodiment shown in FIG. As shown in FIG. 18, a thermal switching device 400 </ b> W is disposed in each of the three-phase current introduction wires 56 that connect the electrode 5 and the superconducting coil 22. When the cryogenic chamber 3 is cooled to a cryogenic state by the cryogenic temperature generator 3, when the second member 600 is cooled to a cryogenic state, the thermal switching device 400W is switched to the first configuration, and the thermal switching device 400W is Conducts electrically. When the thermal switching device 400W is thus conducted, power is supplied from the electrode 5 toward the superconducting coil 22 through the current introduction line 56 and the thermal switching device 400W.

  On the other hand, when the cryogenic temperature generating unit 3 is turned off, the thermal switching device 400W is in the second form as described above, and is thermally and electrically cut off. When the thermal switching device 400W is thus cut off, external heat is prevented from entering the superconducting coil 22 from the electrode 5 via the current introduction line 56 and the thermal switching device 400W. Accordingly, the superconducting coil 22 can be maintained at a low temperature for a long time.

  Further, as shown in FIG. 18, a thermal switching device 400 </ b> X is interposed between the head 33 h of the heat conducting unit 33 and the cold head 32 of the cryogenic temperature generating unit 3. The thermal switch device 400X includes a first member 500 having a male part 503 and a second member 600 having a female part 603 having a female hole 604 into which the male part 503 is fitted. Here, when the cryogenic temperature generator 3 is turned on and the cold head 32 is cooled to an extremely low temperature, the second member 600 of the thermal switch device 400X is cooled to an extremely low temperature by the cold head 32. As a result, the amount of thermal contraction of the female portion 603 of the second member 600 is relatively larger than the amount of thermal contraction of the male portion 503 of the first member 500 in the radial direction (arrow DA2 direction). For this reason, the contact degree in which the inner wall surface 605 of the female portion 603 of the second member 600 contacts the outer wall surface 505 of the male portion 503 of the first member 500 is increased, and the thermal switch device 400X is switched to the first form. According to such a 1st form, the cold heat of the cold head 32 is transmitted to the superconducting coil 22 via the thermal switch apparatus 400X, and the superconducting coil 22 is effectively cooled.

  On the other hand, when the cryogenic temperature generator 3 is turned off, the cold head 32 is gradually heated. Then, the amount of thermal expansion of the female portion 603 of the second member 600 is relatively larger than the amount of thermal expansion of the first member 500 in the radially outward direction (arrow DB2 direction). For this reason, the heat switch device 400X is switched to the second form, and a gap 507 is formed. As a result, the inner wall surface 605 of the female portion 603 of the second member 600 is separated from the outer wall surface 505 of the male portion 503 of the first member 500. To do. Accordingly, the degree of contact between the inner wall surface 605 and the outer wall surface 505 decreases, or the inner wall surface 605 and the outer wall surface 505 are not in contact with each other. According to such a second embodiment, in the thermal switching device 400X, the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 are uniformly spaced all around, and the gap 507 having a uniform gap width. Is preferably formed all around. In this case, the amount of heat penetration from the female portion 603 of the second member 600 into the male portion 503 of the first member 500 is effectively suppressed. In some cases, in the thermal switch device 400X, if the inner wall surface 605 of the female portion 603 and the outer wall surface 505 of the male portion 503 are mostly non-contact, the inner wall surface 605 of the female portion 603 and the outer wall surface of the male portion 503 505 may be in contact with only a part.

  19 and 20 show the relationship between the base material and the coefficient of thermal expansion. In consideration of FIGS. 19 and 20, the first member 500 and the second member 600 are configured such that the base material of the thermal expansion coefficient (thermal contraction rate) of the second member 600 is larger than the base material of the first member 500. The base material can be selected from copper, copper alloy, iron, iron alloy, nickel, nickel alloy, titanium, titanium alloy and the like. Invar, Inco and Inconel alloys have a relatively low coefficient of thermal expansion.

  According to the embodiment applied to the superconducting motor device described above, the cryogenic generator 3 has a structure including a refrigerator. However, the invention is not limited to this, and a cryogenic refrigerant (e.g., liquefied helium) is not limited to this. , Liquefied nitrogen, liquefied oxygen) may be used. The rotor 27 includes a rotary shaft 28 supported so as to be rotatable around an axis P1 and a plurality of permanent magnet portions 29 arranged on the outer peripheral portion of the rotary shaft 28 at intervals in the circumferential direction thereof. Have. However, the present invention is not limited thereto, and the permanent magnet portion may be provided on the stator 20 side, and the superconducting coil 22 may be provided on the rotor 27 side. Although it is applied to the in-vehicle superconducting motor apparatus 1, it is not limited to in-vehicle use, and may be stationary. According to the embodiment applied to the superconducting motor device described above, since the superconducting motor device 1 is a rotary type, the movable element is the rotor 27. However, a linear motion type linear motor that linearly moves the movable element may be used. good. In this case, the stator 20 has a shape extending in one direction, and generates a movable magnetic field that moves the mover linearly. The superconducting motor device 1 is a three-phase motor, but is not limited thereto, and may be a two-phase motor. The rotor 27 has a permanent magnet portion 29, and the stator 20 has a fixed iron core 21 and a superconducting coil 22 that is wound around the fixed iron core 21, but is not limited thereto. The stator may have a permanent magnet portion and the rotor may have a superconducting coil. Although the fixed iron core 21 has a cylindrical shape, a plurality of divided bodies divided in the circumferential direction may be assembled in the circumferential direction to form a cylindrical body. Structures and functions specific to one embodiment can be applied to other embodiments. In addition, the present invention is not limited to the above-described embodiments and examples, and can be implemented with appropriate modifications within a range not departing from the gist.

The following technical idea can also be grasped from the above description.
[Additional Item 1] A superconducting portion exhibiting a superconducting phenomenon below a critical temperature, a heat insulating chamber in which heat transfer from the outside is suppressed, and a base body in which the superconducting portion is accommodated in the heat insulating chamber, and the superconducting portion are A superconducting device comprising: a cooling unit for cooling to a critical temperature or less; and a thermal switch device interposed between the superconducting unit and the cooling unit to transmit the cooling capacity of the cooling unit to the superconducting unit.

  The present invention can be used for, for example, industrial, in-vehicle, and medical superconducting devices.

  1 is a superconducting motor device (superconducting device), 2 is a superconducting motor, 20 is a stator, 21 is a fixed iron core, 22 is a superconducting coil (superconducting portion), 27 is a rotor (movable element), 3 is a cryogenic generator ( (Cooling unit), 30 is a refrigerator, 30a is a compressor, 32 is a cold head, 33 is a heat conduction unit, 4 is a container (base), 41 is an outer vacuum heat insulation chamber, 42 is an inner vacuum heat insulation chamber, and 43 is a first container. 432 is a guide chamber (vacuum heat insulation chamber), 44 is a second container, 45 is a third container, 46 is a fourth container, 41 is an outer vacuum heat insulation chamber, 42 is an inner vacuum heat insulation chamber, and 5 is an electrode (power supply unit). , 400 is a thermal switch device, 500 is a first member, 503 is a male part, 505 is an outer wall surface, 507 is a gap, 521 is a first outer layer, 522 is a second inner layer, 600 is a second member, 603 is a female part, 605 is an inner wall surface, 700 is an object to be cooled, and 621 is a second layer. 622 shows a second inner layer.

Claims (9)

A base body that forms a heat insulating chamber capable of suppressing heat transfer from the outside;
A first member disposed in the heat insulation chamber of the base;
A second member that is disposed in the heat insulating chamber of the base body and at least a part of which is formed using a material having a thermal expansion coefficient larger than that of the first member as a base material;
The first member and the second member have a first form in which the degree of contact between the first member and the second member directly or indirectly increases as the temperature of the second member decreases, As the temperature of the second member increases, the degree of contact with which the first member and the second member come into direct or indirect contact decreases, or the second member can be switched to a second form in which it is non-contact. The thermal switch device characterized by being made.   2. The first member and the second member according to claim 1, wherein the first member is connected to an object to be cooled, and the second member is connected to a cooling unit for exhibiting a cooling ability for cooling the object to be cooled. Is a first form after being cooled by the cooling ability of the cooling section.   The thermal switch device according to claim 1, wherein the first member and the second member form an energization path through which a current flows between the first member and the second member.   The thermal switch device according to claim 1, wherein the first member has a male part, and the second member has a female part surrounding the male part. 5. The male part of the first member according to claim 4, wherein the male part has a cylindrical outer wall surface, and the female part of the second member faces the outer wall surface and has a cylindrical inner wall surface. Have
In the first embodiment, the contact degree between the outer wall surface and the inner wall surface is increased, and in the second embodiment, the contact degree between the outer wall surface and the inner wall surface is reduced or non-contacted. Thermal switch device. 5. The male part of the first member has an outer wall surface inclined in a cross section, and the female part of the second member is inclined in a direction common to the outer wall surface in a cross section. And has an inner wall surface that faces the outer wall surface.
In the first embodiment, the contact degree between the outer wall surface and the inner wall surface is increased, and in the second embodiment, the contact degree between the outer wall surface and the inner wall surface is reduced or non-contacted. Thermal switch device.   7. The device according to claim 1, wherein at least one of the first member and the second member is formed of a plurality of layers, and the first member and the first of the plurality of layers are formed. The layer facing the other of the two members is formed using a material having a coefficient of thermal expansion that increases the degree of contact between the first member and the second member as the temperature of the second member is lowered. A thermal switch device characterized by comprising: A superconducting portion exhibiting a superconducting phenomenon below a critical temperature, a heat insulating chamber that suppresses heat transfer from the outside, a base that accommodates the superconducting portion in the heat insulating chamber, and the superconducting portion cooled below the critical temperature And a thermal switching device that is interposed between the superconducting unit and the cooling unit and transmits the cooling capacity of the cooling unit to the superconducting unit,
The thermal switch device is:
A first member disposed in the heat insulation chamber of the base;
A second member that is disposed in the heat insulating chamber of the base body and at least a part of which is formed using a material having a thermal expansion coefficient larger than that of the first member as a base material;
The first member and the second member have a higher degree of contact with which the first member and the second member are in direct or indirect contact with each other as the second member is cooled by the cooling unit. 1 form and the 2nd form from which the contact degree which the said 1st member and the said 2nd member contact directly or indirectly falls or it becomes non-contact as the said 2nd member heats up A superconducting device characterized in that it can be switched to. A superconducting portion exhibiting a superconducting phenomenon below a critical temperature, a heat insulating chamber that suppresses heat transfer from the outside, a base that accommodates the superconducting portion in the heat insulating chamber, and the superconducting portion are cooled below the critical temperature A cooling unit, a power feeding unit that feeds power to the superconducting unit, and a thermal switch device that is interposed between the superconducting unit and the power feeding unit and feeds power from the power feeding unit to the superconducting unit,
The thermal switch device is:
A first member disposed in the heat insulation chamber of the base;
A second member that is disposed in the heat insulating chamber of the base body and at least a part of which is formed using a material having a thermal expansion coefficient larger than that of the first member as a base material;
The first member and the second member have a higher degree of contact with which the first member and the second member are in direct or indirect contact with each other as the second member is cooled by the cooling unit. 1 form and the 2nd form from which the contact degree which the said 1st member and the said 2nd member contact directly or indirectly falls or it becomes non-contact as the said 2nd member heats up A superconducting device characterized in that it can be switched to.

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