JP2009203875A - Thermomagnetic engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suitably use both of force generated by deformation of shape memory alloy and change of magnetic characteristics of a material having thermomagnetic characteristics. <P>SOLUTION: A material of which deformation temperature at which restoring force to a stored shape is generated and of which magnetic property change temperature at which magnetic properties change from paramagnetic to ferromagnetic are roughly same is used for the shape memory alloy material included in an endless belt 4. When heat of a hot water supplier 5 (heat apply means) and magnetic field by a permanent magnet 7 (magnetic force apply means) are applied on the endless belt 4, restoring force to the stored shape and change of magnetic property from paramagnetic to ferromagnetic are generated in the endless belt 4 at a roughly same temperature. Both of shape memory characteristics and thermomagnetic characteristics can be used simultaneously by an operation cycle of a relatively small temperature range between heating and cooling and can contribute to improvement of energy efficiency and rotation speed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thermomagnetic engine using a material having thermomagnetic properties that change from paramagnetic to ferromagnetic as the temperature rises above a predetermined magnetic change temperature.

  There has been proposed a shape memory alloy engine in which a shape memory endless belt is wound around a pair of pulleys. In the apparatus described in Patent Document 1, a bending moment is generated at a portion that is unwound from one pulley, and the endless belt tries to return to a linear shape or a reverse R shape that is a memorized shape. Based on this bending moment, A rotational force is generated.

  On the other hand, there has been proposed a thermomagnetic engine in which magnetic poles are arranged in the vicinity of a rotating body made of a material having thermomagnetic characteristics in which magnetism changes according to temperature. In the apparatus described in Patent Document 2, a part of the rotating body is heated so as to exceed the so-called Curie temperature, thereby generating a low saturation magnetic flux density region and a high saturation magnetic flux density, which are arranged in the vicinity of the boundary between them. A rotational force is generated by the action of the magnetic pole.

JP 2006-207441 A JP-A-9-268968

  By the way, it would be advantageous if both the restoring force of the shape memory alloy and the magnetic change of the material having thermomagnetic properties can be used simultaneously. However, since the Curie temperature at which the magnetic change occurs is significantly higher than the deformation temperature of the shape memory alloy, it is necessary to increase the temperature range of heating and cooling in the operation cycle in order to use both characteristics. There is a problem that it is scarce.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a thermomagnetic engine that can suitably use both the force generated with deformation of a shape memory alloy and the change in magnetic properties of a material having thermomagnetic properties.

  In order to solve the above-described problems, the thermomagnetic engine according to the present invention has a shape memory characteristic that generates a restoring force to a pre-stored shape with a temperature rise exceeding a predetermined deformation temperature, and a predetermined magnetic change temperature. An endless belt containing a material having a thermomagnetic property that changes from paramagnetic to ferromagnetic with a temperature rise exceeding the temperature, and a heat applying means and a magnetic force applying means arranged to act on the endless belt. Is characterized in that the deformation temperature and the magnetic change temperature are substantially equal.

  In the present invention, as the material included in the endless belt, a material having a deformation temperature that generates a restoring force to a previously stored shape and a magnetic change temperature that changes from paramagnetism to ferromagnetism is approximately equal. When the heating by the applying means and the magnetic field by the magnetic applying means act on the endless belt, the endless belt has a restoring force to a pre-stored shape and a change in magnetism from paramagnetic to ferromagnetic at substantially the same temperature. . Therefore, both shape memory characteristics and thermomagnetic characteristics can be utilized simultaneously by an operation cycle having a relatively small temperature range for heating and cooling. This can contribute to improvement in energy efficiency and rotation speed.

  In the thermomagnetic engine described in Patent Document 2 described above, by heating a part of the rotating body so as to exceed the Curie point, the saturation magnetic flux density of the part of the thermomagnetic material is reduced, and the other parts However, the Curie point is generally relatively high, and the temperature may be lower if energy efficiency and device durability are taken into consideration. desirable. In this regard, as shown in FIG. 4, the conventionally known thermomagnetic material (dashed line a) has only a change from ferromagnetism to paramagnetism (region II) when the temperature rises above the Curie point. In contrast to the fact that there was no significant magnetic change in the lower temperature region, recent research has shown that in certain thermomagnetic materials, the temperature rises in the lower temperature region I than the Curie point, as shown by the solid line a. Along with this, it has been discovered that a magnetic change from paramagnetism (martensite phase, M phase) to ferromagnetism (austenite phase, A phase) occurs. In the present invention, the use of such a material makes it possible to set the operating temperature to a relatively low value.

  It is preferable that the magnetic force application means in the present invention is disposed adjacent to the heat application means in the traveling direction of the endless belt. In this case, since the magnetic field from the magnetic force applying means acts on the endless belt portion in a state where the heating by the heat applying means has progressed and the magnetism has been strengthened, the rotational force due to the magnetic field can be suitably applied.

  The magnetic force application means in the present invention is preferably arranged inside the region defined by the endless belt. In this case, slipping can be suppressed by the action of attracting the endless belt to the pulley in the vicinity of the portion that is circulated from the pulley.

  In the present invention, the endless belt is wound around a pair of pulleys, the heat applying means is disposed in the vicinity of one of the pair of pulleys, and the magnetic force applying means is disposed in the vicinity of the other pulley. It is preferred that In this case, since the magnetic field from the magnetic force applying means acts on the endless belt portion in a state where the heating by the heat applying means has progressed and the magnetism has been strengthened, the endless belt can be suitably prevented from slipping.

  In this case, the magnetic force applying means is preferably arranged along the peripheral surface of the other pulley, and is further arranged in an annular shape inside the peripheral surface of the other pulley. Particularly preferred.

  Embodiments of the present invention will be described below with reference to the drawings. A thermomagnetic engine 1 according to the first embodiment shown in FIGS. 1 to 3 includes a low temperature side pulley 2 and a high temperature side pulley 3, an endless belt 4 wound around the pair of pulleys 2, 3, and an endless belt 4. Are provided with a hot water supply device 5, a cold water supply device 6 and a permanent magnet 7.

The low temperature side pulley 2 has a larger diameter than the high temperature side pulley 3 (r _c > r _h ). The axis of the low temperature side pulley 2 is arranged in parallel and vertically above the axis of the high temperature side pulley 3. The low temperature side pulley 2 is supported by a shaft 12 fixed to the support column 11 and is rotatable by a bearing 13 provided on the shaft 12. The high temperature side pulley 3 is fixed to the output shaft 14, and the output shaft 14 is rotatably supported by a bearing 15 provided on the support 11.

The endless belt 4 contains a shape memory material. As the shape memory material used in the present embodiment, the restoring force to a previously memorized shape and the change in magnetism from paramagnetism (martensite phase, M phase) to ferromagnetism (austenite phase, A phase) but it is preferred to use approximately equal temperature (e.g., about 30 ° C) that occur as the temperature rises in excess of, for example, Ni ₅₀ Mn _50-y Sn y or _{Ni 50 Mn 50-y Sb y} . Such a shape memory material is obtained by inductively heating particulate raw materials mixed at a desired mass ratio in an argon atmosphere, slicing the resulting ingot, and homogenizing at 1000 ° C for one day in a vacuum. After that, it can be obtained by quenching in water. The deformation of the shape memory material and the transformation from paramagnetism to ferromagnetism are reversible and may have a predetermined hysteresis.

  As shown in FIG. 3, the endless belt 4 in the present embodiment is formed by alternately laminating layers 4p made of a shape memory material foil or a single crystal and an elastomer layer 4q, and deformed into a saw blade shape or a zigzag shape. It has a ribbon shape. The endless belt 4 is in an elongated state in which the pitch p, which is the interval between adjacent valleys, takes a relatively large value at room temperature, and is relatively high in a region where the deformation temperature (for example, 30 ° C.) is higher. The shape is stored in advance so that a degenerated state having a small value is obtained.

  The hot water supply device 5 can supply hot water such as engine cooling water from an on-vehicle radiator (not shown) to the endless belt 4 continuously or intermittently. Hot water from the hot water supplier 5 is supplied to a linear portion 4 h of the endless belt 4 from the low temperature side pulley 2 to the high temperature side pulley 3.

  The cold water feeder 6 can supply cold water from a cold water tank (not shown), for example, continuously or intermittently toward the endless belt 4. The cold water from the cold water feeder 6 is supplied to a portion 4 c that is lower in temperature than the hot water and extends from the high temperature side pulley 3 to the low temperature side pulley 2 in the endless belt 4.

  The permanent magnet 7 is arranged along the traveling path of the endless belt 4 so as to cover the linear portion 4c extending from the lower side of the high temperature side pulley 3 to the low temperature side pulley 2 of the endless belt 4. The magnetic field is arranged on the outer side so that the magnetic field can act on the endless belt 4. The permanent magnet 7 is fixed to the magnet base 16, and the magnet base 16 and the support column 11 are fixed to the base 17.

  In the above configuration, when the hot water from the hot water supply device 5 is supplied to the high temperature portion 4h of the endless belt 4 and the cold water from the cold water supply device is supplied to the low temperature portion 4c of the endless belt 4, the high temperature portion 4h. At least part of the temperature rises above the deformation temperature and magnetic change temperature of the shape memory material contained therein, the endless belt is deformed into a pre-stored degenerated state, and the magnetic properties of the shape memory material are paramagnetic. It changes from (M phase) to ferromagnetism (A phase). On the other hand, the temperature of at least a part of the low temperature portion 4c is lowered below the deformation temperature and the magnetic change temperature by cooling, and returns to the extended state and paramagnetic (M phase).

  The force generated by the contraction of the high temperature portion 4h acts in the direction in which the low temperature side pulley 2 and the high temperature side pulley 3 are rotated in the opposite direction, but the radius rc of the low temperature side pulley 2 is greater than the radius rh of the high temperature side pulley 3. Therefore, the low temperature side torque Fc is larger than the high temperature side torque Fh, and the endless belt 4 generates a rotational force in the R direction in the figure. Further, since the magnetic properties of the high temperature portion 4h are ferromagnetic and the low temperature portion 4c is paramagnetic, the endless belt 4 similarly generates a rotational force in the R direction in the figure due to the attractive force of the permanent magnet 7. Therefore, the thermomagnetic engine 1 rotates in the R direction in the drawing while the supply of hot water and cold water continues.

  As described above, in the first embodiment, the shape memory material included in the endless belt 4 has a deformation temperature that generates a restoring force to a previously stored shape and a magnetic change temperature that changes from paramagnetic to ferromagnetic. Since substantially the same material is used, when the heating by the hot water supply device 5 (heat applying means) and the magnetic field by the permanent magnet 7 (magnetic force applying means) act on the endless belt 4, the endless belt 4 has a shape stored in advance. And the change in magnetism from paramagnetism to ferromagnetism occur at substantially the same temperature. Therefore, both shape memory characteristics and thermomagnetic characteristics can be utilized simultaneously by an operation cycle having a relatively small temperature range for heating and cooling. This can contribute to improvement in energy efficiency and rotation speed.

  In this embodiment, as indicated by a solid line a in FIG. 4, paramagnetic (martensite phase, M phase) to ferromagnetism (austenite phase, A phase) as the temperature rises in a region I lower than the Curie point. It is possible to set the operating temperature to a relatively lower value than the region II in the vicinity of the Curie point. This is advantageous in terms of energy efficiency and device durability.

  Moreover, in this embodiment, since the permanent magnet 7 (magnetic force provision means) is arrange | positioned adjacent to the running direction of the endless belt 4 with respect to the warm water supply device 5 (heat provision means), the heating by the warm water supply device 5 advances. The magnetic field from the permanent magnet 7 acts on the endless belt 4 in a state where the magnetism is strengthened. Therefore, the rotational force by a magnetic field can be provided suitably.

  Next, a second embodiment of the present invention will be described. A thermomagnetic engine 101 according to the second embodiment shown in FIGS. 5 to 9 includes a low temperature pulley 102 and a high temperature pulley 103, an endless belt 104 wound around the pair of pulleys 102, 103, and an endless belt 104. And a hot water tank 105 disposed so as to be capable of acting on the water.

The low temperature side pulley 102 has a larger diameter than the high temperature side pulley 103 (r _c > r _h ). The axis line of the low temperature side pulley 102 is arranged in a position parallel to the axis line of the high temperature side pulley 103 and shifted from above in the vertical direction. The low temperature side pulley 102 is fixed to a shaft 112, and the shaft 112 is rotatably supported by a bearing 113 provided on a support column 111 (see FIG. 6). The high temperature side pulley 103 is fixed to the output shaft 114, and the output shaft 114 is rotatably supported by a bearing 115 provided on the support column 111. The low temperature side pulley 103 may be solid or hollow.

  The endless belt 104 contains a shape memory material. As the shape memory material used in this embodiment, it is preferable to use the same material as the endless belt 104 in the first embodiment. The endless belt 104 in this embodiment is, for example, one in which particles 104p of a shape memory material are dispersed in an elastomer (FIG. 7), or one in which a linear molded product 104q of a shape memory material is bundled and impregnated with an elastomer (FIG. 8). ), Or a layer of shape memory material foil 104r and elastomer layer 104s alternately stacked (FIG. 9) can be used, but is not limited thereto. The endless belt 104 is relatively soft (low Young's modulus) at normal temperature and relatively hard (high Young's modulus) in a region higher than the deformation temperature (for example, 30 ° C), or the pulley 102, The shape is stored in advance so as to have a reverse r shape opposite to the arcuate contour of 103.

  The hot water tank 105 is configured such that hot water such as engine cooling water from an on-vehicle radiator (not shown) is continuously supplied, for example. The water level of the hot water in the hot water tank 105 is set so that a part of the high temperature side pulley 103, in particular, a portion 103 a where the endless belt 104 extends from the high temperature side pulley 103 is immersed.

  A cylindrical permanent magnet 107 is integrally disposed with the low temperature side pulley 102 along the peripheral surface of the low temperature side pulley 102 and inside the peripheral surface. The magnetic field from the permanent magnet 107 can act on the endless belt 104.

  In the above configuration, when the heat from the hot water in the hot water tank 105 acts on the endless belt 104, at least a part of the high temperature portion 104h immersed in the hot water in the endless belt 104 contains the shape memory material contained therein. Rises above the deformation temperature and magnetic change temperature of the material and deforms into a pre-stored linear shape or reverse r shape, and the magnetic properties of the shape memory material change from paramagnetic (M phase) to ferromagnetic (A phase) Change. On the other hand, the temperature of at least a part of the low temperature portion, which is the remaining portion of the endless belt 104, falls below the deformation temperature and the magnetic change temperature by cooling with the outside air, and returns to soft and paramagnetic (M phase).

  The bending moment accompanying the deformation of the high temperature portion 104h acts to bulge the lower straight portion 104s of the endless belt 104 outward as indicated by a two-dot chain line 104s' in the figure. The tension acts on the endless belt 104 in the direction R in the figure because the portion of the endless belt 104 that is going to be linear or reverse r-shaped shifts to a stable posture located in the common tangential region of the pulleys 102 and 103. Directional rotational force is generated. Further, since the magnetic properties of the high temperature portion 4h are ferromagnetic and the remaining low temperature portion is paramagnetic, the endless belt 104 also has a rotational force in the R direction in the figure due to the attractive force of the permanent magnet 107. Arise. Therefore, the thermomagnetic engine 1 rotates in the R direction in the figure while the supply of hot water continues.

  As described above, in the second embodiment, the shape memory material included in the endless belt 104 has a deformation temperature that generates a restoring force to a previously stored shape and a magnetic change temperature that changes from paramagnetic to ferromagnetic. Since substantially the same material is used, both the shape memory characteristic and the thermomagnetic characteristic can be simultaneously utilized by an operation cycle having a relatively small temperature range for heating and cooling, as in the first embodiment. This can contribute to improvement in energy efficiency and rotation speed.

  In the present embodiment, the permanent magnet 107 (magnetic force applying means) is arranged adjacent to the hot water tank 105 (heat applying means) in the traveling direction of the endless belt 104, so that the heating by the hot water tank 105 proceeds and the magnetism is increased. The magnetic field from the permanent magnet 107 acts on the endless belt 104 in a state where the strength of the endless belt 104 is increased. Therefore, the rotational force by a magnetic field can be provided suitably.

  In this embodiment, since the permanent magnet 107 (magnetic force applying means) is disposed inside the region defined by the endless belt 104, the installation space of the magnetic force applying means can be suppressed and the permanent magnet 107 can be routed from the high temperature side pulley 103. Slip can be suppressed by the action of attracting the endless belt 104 to the high-temperature pulley 103 in the vicinity of the portion 103a to be operated.

  In the present embodiment, a hot water tank 105 (heat application means) is disposed in the vicinity of one of the pair of pulleys 102 and 103 near the high temperature side pulley 103, and a permanent magnet 107 ( Magnetic force applying means) is arranged. Therefore, since the endless belt is brought into the low temperature side pulley 102 in a state in which the endless belt is heated and magnetized, the slip of the endless belt 104 can be suitably suppressed.

  Moreover, in this embodiment, since the permanent magnet 107 is arrange | positioned along the surrounding surface of the low temperature side pulley 102, and was arrange | positioned annularly inside the surrounding surface of the low temperature side pulley 102, the installation space of a magnetic force provision means can be suppressed.

  Further, instead of or in addition to the permanent magnet 107 in the second embodiment, the permanent magnet 117 (FIG. 5) is located at a fixed position inside the endless belt 104 along the traveling path and adjacent to the high temperature portion 104h. Reference) may be arranged. In this case, the winding angle around the pulley 102 can be increased by the attractive force of the permanent magnet 117, and slipping of the endless belt 104 can be suitably suppressed.

  10 and 11, the inner iron core 127 is provided inside the low temperature side pulley 102 and the track of the endless belt 104 along the outer peripheral surface of the low temperature side pulley 102. A magnetic path former 130 composed of a permanent magnet 128 and an external iron core 129 may be arranged so as to cover In this case, since the formation of a magnetic path through the permanent magnet 128, the outer iron core 129, and the inner iron core 127 is promoted, a magnetic force can be more suitably applied to the endless belt 104.

  Next, a third embodiment of the present invention will be described. A thermomagnetic engine 201 according to the third embodiment shown in FIG. 12 includes a pulley 202, an endless belt 204 wound around the pulley 202, and a hot water tank 205 disposed so as to act on the endless belt 204. ing.

  The endless belt 204 includes the same shape memory material as the endless belt 4 in the first embodiment described above, and has a structure bent in a wavy or zigzag manner. However, the endless belt 204 has a number of weights 204a fixed thereto. Different. The endless belt 204 is preliminarily stored in a shape so that it degenerates in a region higher than the deformation temperature (for example, 30 ° C.) and the interval (pitch) between the weights 204a becomes a relatively small value p1. At room temperature below the deformation temperature, the endless belt 204 extends and the pitch of the weights 204a becomes a relatively large value p2. The pitch of the weights 204a is equally spaced throughout the endless belt 204 at the same temperature.

  The pulley 202 is entirely disposed at a position higher than the water surface of the hot water tank 205. The pulley 202 is fixed to the output shaft 212. A large number of recesses 202a for engaging the weight 204a are formed on the peripheral surface of the pulley 202, and the recesses 202a are arranged at equiangular intervals corresponding to the pitch of the endless belt 204 extended.

  The hot water tank 205 is configured to be continuously supplied with hot water such as engine cooling water from an on-vehicle radiator (not shown), for example. The hot water enters the hot water layer 205 from the supply port 205a and is discharged from the discharge port 205b. In the hot water tank 205, a spacer 205d that separates the high temperature side 205h and the low temperature side 205c, and two cylindrical guides 205e that guide the endless belt 204 are disposed.

  A spiral cooling pipe 206 through which the endless belt 204 passes, and a cylindrical permanent magnet through which the endless belt 204 passes, are provided at the bottom of the hot water tank 205, which is an intermediate part between the high temperature side 205h and the low temperature side 205c. 207 is arranged. The cooling pipe 206 can cool the endless belt 204 below the deformation temperature and the magnetic change temperature by supplying cold water from the outside. The magnetic field of the permanent magnet 207 can act on the endless belt 204.

  In the above configuration, when the heat from the hot water in the hot water tank 205 acts on the endless belt 204, at least a part of the temperature of the high temperature portion of the endless belt 204 on the high temperature side of the endless belt 204 is contained therein. The temperature rises beyond the deformation temperature and the magnetic change temperature of the material and deforms into a prestored degenerated shape, and the magnetic properties of the shape memory material change from paramagnetic (M phase) to ferromagnetic (A phase). On the other hand, the temperature of at least a part of the low temperature portion, which is the remaining portion of the endless belt 104, falls below the deformation temperature and the magnetic change temperature due to cooling of the cooling pipe 206, and returns to the extended state and paramagnetic (M phase). To do.

  When the pitch of the weight 204a is reduced from p2 to p1 due to the shrinkage of the high temperature portion, the number of weights 204a existing on the high temperature side 205h becomes larger than that on the low temperature side 205c. In the figure, a rotational force in the R direction is generated. Therefore, the thermomagnetic engine 201 rotates in the R direction in the figure while the supply of hot water continues.

  As described above, in the third embodiment, the shape memory material included in the endless belt 204 has a deformation temperature that generates a restoring force to a previously stored shape and a magnetic change temperature that changes from paramagnetic to ferromagnetic. Since substantially the same material is used, both the shape memory characteristic and the thermomagnetic characteristic can be simultaneously utilized by an operation cycle having a relatively small temperature range for heating and cooling, as in the first embodiment. This can contribute to improvement in energy efficiency and rotation speed.

  In this embodiment, the permanent magnet 207 (magnetic force applying means) is adjacent to the traveling direction of the endless belt 104 with respect to the high temperature side 205h (heat applying means) of the hot water tank 205 with respect to the traveling direction of the endless belt 204. The magnetic field from the permanent magnet 207 acts on the portion of the endless belt 204 in the state where the heating by the high temperature side 205h has progressed and the magnetism has been strengthened. Therefore, the rotational force by a magnetic field can be provided suitably.

  Next, a fourth embodiment of the present invention will be described. The thermomagnetic engine 301 of the fourth embodiment shown in FIG. 13 includes a first pulley 302 and a second pulley 303 that are rotatably supported, and an endless belt 304 wound around the pair of pulleys 302 and 303. And a hot water tank 305 disposed so as to be able to act on the endless belt 304.

  The first pulley 302 and the second pulley 303 have the same diameter, and the shaft height positions are equal to each other. In the present embodiment, the endless transmission belt 324 and the large-diameter transmission pulley 322 (radius r1) wound around the endless transmission belt 324 are separated from the endless belt 304 including the shape memory material and the pulleys 302 and 303 (radius r0) wound around the endless belt 304. ), A small-diameter transmission pulley 323 (radius r2) is used. A large-diameter transmission pulley 322 is fixed to the first pulley 302, and a small-diameter transmission pulley 323 is fixed to the second pulley 303 coaxially. The friction resistances of the bearing portions of the first pulley 302 and the second pulley 303 are equal to each other.

  A lower straight portion 304 h of the endless belt 304 positioned below the first pulley 302 and the second pulley 303 is immersed in hot water (not shown) in the hot water tank 305. On the other hand, the straight portion of the endless belt 304 located above the first pulley 302 and the second pulley 303 is curved downward by the three idler pulleys 432, and cold water (not shown) in the cold water layer 306 is formed. Soaked in

  The endless belt 304 contains a shape memory material. As the shape memory material used in this embodiment, it is preferable to use the same material as the endless belt 4 in the first embodiment. The structure of the endless belt 304 is preferably the same as that of the endless belt 104 in the second embodiment. Support plates 306 and 308 for suppressing drooping are disposed below the upper straight portion of the endless belt 304 and below the lower straight portion.

  The hot water tank 305 is configured to be continuously supplied with hot water such as engine cooling water from a vehicle-mounted radiator (not shown), for example. The level of the hot water in the hot water tank 305 is set so that a part of the pulleys 302 and 303, in particular, a portion where the endless belt 304 comes out from the pulleys 302 and 303 is immersed.

  A permanent magnet 307 is arranged along the track of the endless belt 304 including the upper side of the peripheral surface of the first pulley 302. A magnetic field from the permanent magnet 307 can act on the endless belt 304.

  In the fourth embodiment, a large number of endless belts 304 arranged in parallel to each other in the axial direction are used, and the pulleys 302 and 303 are pulleys with multiple grooves so that the large number of endless belts 304 are wound. It has become. One of the pulleys 302 and 303 (not shown) is an output shaft.

  In the above configuration, when the heat from the hot water in the hot water tank 305 acts on the endless belt 304, the temperature of at least a part of the lower straight portion 304h (high temperature portion) immersed in the hot water in the endless belt 304 is reduced. It exceeds the deformation temperature and the magnetic change temperature of the shape memory material contained, and is deformed into a previously stored linear shape or reverse r shape, and the magnetic properties of the shape memory material change from paramagnetic (M phase) to ferromagnetic (A Phase). On the other hand, the temperature of at least a part of the low-temperature portion, which is the remaining portion of the endless belt 304, falls below the deformation temperature and the magnetic change temperature by cooling, and returns to soft and paramagnetic (M phase).

  The bending moment accompanying the deformation of the lower straight portion 304h, which is a high temperature portion, acts to bulge the lower straight portion 304h downward in the figure, and the tension of the endless belt 304 at that time is linear. The portion of the endless belt 304 that is going to act acts in the direction of shifting to a stable posture located in the linear region between the pulleys 302 and 303. Here, since the radius r1 of the large-diameter transmission pulley 322 is larger than the radius r2 of the small-diameter transmission pulley 323, the drag of the large-diameter transmission pulley 322 becomes relatively large, and the endless belt 304 has an R direction in the figure. The rotational force is generated. Further, since the magnetic property of the lower straight portion 304h that becomes high temperature is ferromagnetic, and the low temperature portion that is the remaining portion is paramagnetic, the endless belt 304 is similarly R in the figure by the attractive force of the permanent magnet 307. Directional rotational force is generated. Therefore, the thermomagnetic engine 301 rotates in the R direction in the drawing while the supply of hot water continues.

  As described above, in the fourth embodiment, the shape memory material included in the endless belt 304 has a deformation temperature that generates a restoring force to a previously stored shape and a magnetic change temperature that changes from paramagnetic to ferromagnetic. Since substantially the same material is used, both the shape memory characteristic and the thermomagnetic characteristic can be simultaneously utilized by an operation cycle having a relatively small temperature range for heating and cooling, as in the first embodiment. This can contribute to improvement in energy efficiency and rotation speed.

  In the present embodiment, the permanent magnet 307 (magnetic force applying means) is disposed adjacent to the hot water tank 305 (heat applying means) in the traveling direction of the endless belt 304, so that the heating by the hot water tank 305 proceeds and the magnetism is increased. The magnetic field from the permanent magnet 307 acts on the portion of the endless belt 304 in a state where the strength is increased. Therefore, the rotational force by a magnetic field can be provided suitably.

  In the above embodiments, the present invention has been described with a certain degree of concreteness, but various modifications and changes can be made to the present invention without departing from the spirit and scope of the invention described in the claims. It must be understood that it is possible. That is, the present invention includes modifications and changes that fall within the scope and spirit of the appended claims and their equivalents. For example, the deformation temperature of the shape memory material and the magnetic change temperature of the thermomagnetic material are not limited to the same, but may be the same within a predetermined error range. Moreover, as a magnetic force provision means, it may replace with a permanent magnet and may use an electromagnet. Further, as the heat applying means, a heat source other than the engine cooling water, for example, heat from an engine exhaust pipe or an oil pan may be used, and such a modification belongs to the category of the present invention.

It is a front view showing a schematic structure of a thermomagnetic engine of a 1st embodiment of the present invention. It is a side view which shows the cross section of 1st Embodiment. It is a perspective view which shows the endless belt in 1st Embodiment. It is a graph which shows the thermomagnetic characteristic of the material used suitably for 1st Embodiment. It is a front view which shows schematic structure of the thermomagnetic engine of 2nd Embodiment. It is a side view which shows the cross section of 2nd Embodiment. It is sectional drawing which shows the structural example of the endless belt in 2nd Embodiment. It is sectional drawing which shows another structural example of the endless belt in 2nd Embodiment. It is sectional drawing which shows another structural example of the endless belt in 2nd Embodiment. It is a front view which shows the principal part of the modification of 2nd Embodiment. It is a side view which shows the cross section of the principal part of the modification of 2nd Embodiment. It is a front view which shows schematic structure of the thermomagnetic engine of 3rd Embodiment. It is a front view which shows schematic structure of the thermomagnetic engine of 4th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101,121,201,301 Thermomagnetic engine 2,102 Low temperature side pulley 3,103 High temperature side pulley 4,104,204,304 Endless belt 5 Hot water supply device 6 Cold water supply device 7,107,117,128,207 , 307 Permanent magnet 14, 114, 212 Output shaft

Claims (6)

A shape memory characteristic that generates a restoring force to a pre-stored shape as the temperature rises above a predetermined deformation temperature, and a thermomagnetic characteristic that changes from paramagnetic to ferromagnetic as the temperature rises above a predetermined magnetic change temperature. An endless belt comprising a material having;
A heat application means and a magnetic force application means arranged so as to act on the endless belt;
With
The thermomagnetic engine, wherein the material has the deformation temperature and the magnetic change temperature substantially equal. The thermomagnetic engine according to claim 1,
The thermomagnetic engine, wherein the magnetic force applying means is disposed adjacent to the heat applying means in the traveling direction of the endless belt. The thermomagnetic engine according to claim 1 or 2,
The thermomagnetic engine, wherein the magnetic force applying means is disposed inside a region defined by the endless belt. The thermomagnetic engine according to any one of claims 1 to 3,
The endless belt is wound around a pair of pulleys;
A thermomagnetic engine characterized in that the heat applying means is arranged in the vicinity of one pulley of the pair of pulleys, and the magnetic force applying means is arranged in the vicinity of the other pulley. The thermomagnetic engine according to claim 4,
The thermomagnetic engine, wherein the magnetic force applying means is disposed along a peripheral surface of the other pulley. The thermomagnetic engine according to claim 4,
The thermomagnetic engine, wherein the magnetic force applying means is annularly arranged inside the peripheral surface of the other pulley.

Images