WO2007114309A1

WO2007114309A1 - Latent-heat storage device, engine start facilitation device, and engine

Info

Publication number: WO2007114309A1
Application number: PCT/JP2007/057013
Authority: WO
Inventors: Kenichi Yamada; Hideo Kobayashi; Katuhiko Arisawa; Yoshio Yamashita; Kunihiko Hayashi; Ryu Hamaguchi; Tomoyuki Suzuki; Arata Kobayashi; Yuki Sato; Fumikazu Sano
Original assignee: Toyota Jidosha Kabushiki Kaisha; Futaba Industrial Co., Ltd.; Chuo Hatsujo Kabushiki Kaisha; Aisan Kogyo Kabushiki Kaisha
Priority date: 2006-03-29
Filing date: 2007-03-23
Publication date: 2007-10-11
Also published as: JP2007263045A

Abstract

A cylinder block water jacket 112e formed in a cylinder block 112 accommodates a latent-heat storage material container 120. A magnetic-field generator 130 is disposed externally of the latent-heat storage material container 120. The latent-heat storage material container 120 accommodates a movable magnetic plate 141 and a trigger member 142. The trigger member 142 is disposed between the movable magnetic plate 141 and the magnetic-field generator 130. Upon subjection to a magnetic field generated in the magnetic-field generator 130, the movable magnetic plate 141 moves toward the magnetic-field generator 130. The moving movable magnetic plate 141 presses and elastically deforms the trigger member 142. This elastic deformation causes release of latent heat from a supercooled latent-heat storage material.

Description

DESCRIPTION

LATENT-HEAT STORAGE DEVICE, ENGINE START FACILITATION DEVICE, AND ENGINE

TECHNICAL FIELD

The present invention relates to a latent-heat storage device for retaining latent heat therein in a releasable manner. Also, the invention relates to an engine start facilitation device for thermally facilitating starting of an engine. Furthermore, the invention relates to an engine in which the temperature of a cooling medium can be rapidly increased during starting thereof.

BACKGROUND ART

A known latent-heat storage device utilizes release of latent heat from a so-called latent-heat storage material. The latent-heat storage material is a substance that can retain latent heat therein in a supercooled state and can release the latent heat therefrom through cancellation of the supercooled state being triggered by a certain external stimulus. A known latent-heat storage material is, for example, sodium acetate trihydrate (CH₃COONa-3H₂θ). A latent-heat storage device of this type can cancel a supercooled state of a supercooled latent-heat storage material by giving the above-mentioned stimulus to the supercooled latent-heat storage material.

Japanese Patent Application Laid-Open (kokai) No. 63-105219 (Patent Document 1) discloses an example configuration of an engine having a latent-heat storage device of this type. The latent-heat storage device is configured such that the same can be provided in a cooling water path of the engine. Particularly, the latent-heat storage device is configured such that the same can be accommodated in the cooling water path in a cylinder head. The latent-heat storage device includes a heating container, a heat-insulated container, an activator, a communication portion, and an on-off valve.

The heating container contains the latent-heat storage material. The heat-insulated container is provided adjacent to the heating container. The heat-insulated container contains an activator. The activator is, for example, a crystalline substance (solid) of the latent-heat storage material. Upon contact with the latent-heat storage material, the activator can cause the latent-heat storage material to undergo a phase transition from the gel phase to the solid phase. The communication portion enables communication between the heating container and the heat-insulated container. The on-off valve is provided at the communication portion. The on-off valve is fixed to a distal end portion of a rod, which is operated by an actuator. The rod extends through the heat-insulated container.

According to the above-mentioned configuration, when the engine is started, the actuator operates the rod so as to open the on-off valve for establishing communication through the communication portion. As a result, the gelled latent-heat storage material contained in the heating container is solidified through contact with the activator. The phase transition of the latent-heat storage material from the gel phase to the solid phase causes release of latent heat from the latent-heat storage material. The released latent heat heats the cooling water of the engine. That is, the warming-up of the engine is facilitated.

After the warming-up of the engine is completed, the cooling water heats the latent-heat storage material. This causes the latent-heat storage material to undergo phase transition from the solid phase to the liquid phase. This phase transition causes the latent-heat storage material to store latent heat therein. Subsequently, the on-off valve closes the communication portion.

Japanese Patent Application Laid-Open (kokai) No. 11-182393 (Patent Document 2) discloses another example configuration of an engine having a latent-heat storage device of this type. In this engine, a heat storage material chamber that contains the latent-heat storage material is formed in a cylinder block. The heat storage material chamber is provided in such a manner as to surround a cylinder. A pair of electrodes connected to a predetermined power supply is exposed to the latent-heat storage material.

According to the above-mentioned configuration, when the engine is cold-started, a predetermined voltage is applied between the paired electrodes. This gives an electrical stimulus to the latent-heat storage material in a supercooled state. This electrical stimulus cancels the supercooled state of the latent-heat storage material, so that the stored latent heat is released from the latent-heat storage material. After the warming-up of the engine is completed, heat transferred from the cylinder block melts the latent-heat storage material. Thus, the latent-heat storage material stores latent heat therein.

However, the above-mentioned latent-heat storage device of this kind and an engine having such a latent-heat storage device involve various problems.

For example, in the latent-heat storage device disclosed in Japanese Patent Application Laid-Open (kokai) No. 63-105219 (Patent Document 1), the latent-heat storage material may leak out through a portion of the heat-insulated container through which the rod extends. Particularly, in the case where the latent-heat storage device is disposed within the cooling water path, the cooling water from the cooling water path may enter the heat-insulated container or the heating container. In this case, impurities are mixed in the latent-heat storage material. Mixing impurities in the latent-heat storage material may hinder the latent-heat storage material from storing latent heat therein and releasing latent heat therefrom.

Also, in the latent-heat storage device disclosed in Japanese Patent Application Laid-Open (kokai) No. 63-105219 (Patent Document 1), before cold start, failure of the on-off valve to completely close the communication portion may cause erroneous contact of the activator with the latent-heat storage material. In this case, the supercooled state of the latent-heat storage material is imprudently canceled before cold start. As a result, before cold start, the latent-heat storage material fails to retain latent heat therein. Thus, even when the on-off valve is operated during later cold start, starting of the engine cannot be thermally facilitated.

The latent-heat storage device disclosed in Japanese Patent Application Laid-Open (kokai) No. 11-182393 (Patent Document 2) usually uses silver or silver alloy to form at least a positive electrode (preferably both positive and negative electrodes) of the paired electrodes in order to improve reliability in canceling the supercooled state of the latent-heat storage material. Accordingly, the cost of manufacturing the latent-heat storage device increases.

Also, even when the positive electrode of silver is used, reliability in canceling the supercooled state of the latent-heat storage material is poor. Specifically, when voltage is applied, the surface of the positive electrode of silver is covered with silver oxide through electrochemical reaction on the positive electrode of silver. For the positive electrode of silver covered with silver oxide, canceling the supercooled state becomes difficult.

The present invention has been accomplished for solving the above-mentioned problems, and an object of the invention is to provide a latent-heat storage device capable of reliably releasing latent heat therefrom; an engine start facilitation device capable of thermally facilitating starting of an engine in an improved fashion; and an engine in which the temperature of a cooling medium can be raised in an improved fashion during starting thereof.

DISCLOSURE OF THE INVENTION

To achieve the above object, a latent-heat storage device of the present invention is configured so as to retain latent heat therein in a releasable manner. The latent-heat storage device comprises a latent-heat storage material, a latent-heat storage material container, an electromagnetic-field generator, and a supercooling canceler.

The latent-heat storage material retains latent heat therein in a supercooled state and releases the latent heat therefrom through cancellation of the supercooled state. The latent-heat storage material container assumes the form of a closed container which internally has a latent-heat-storage-material-accommodating section which is a space for accommodating the latent-heat storage material in a liquid-tight manner. The electromagnetic-field generator generates an electromagnetic field (electric field and/or magnetic field) at the outside of the latent-heat-storage-material-accommodating section. The supercooling canceler is disposed in the latent-heat storage material container. The supercooling canceler cancels the supercooled state of the latent-heat storage material through mechanical operation thereof in the latent-heat storage material in the supercooled state, the mechanical operation being effected by the electromagnetic field.

According to the above-mentioned configuration, the electromagnetic-field generator generates a predetermined electromagnetic field at the outside of the latent-heat-storage-material-accommodating section. The electromagnetic field causes the supercooling canceler to mechanically operate in the latent-heat storage material container in the form of a closed container which accommodates the latent-heat storage material in the supercooled state. Examples of the mechanical operation include elastic deformation, generation of stress, and compression of the latent-heat storage material.

The mechanical operation cancels the supercooled state of a small amount of the latent-heat storage material proximate to the supercooling canceler in the latent-heat storage material container. As a result, the small amount of the latent-heat storage material undergoes phase transition to the solid phase. That is, small nuclei of the solid phase are formed. The formation of the small nuclei of the solid phase causes cancellation of the supercooled state to chain-react to the latent-heat storage material surrounding the nuclei, followed by associated phase transition. As a result, the latent heat is released from the latent-heat storage material.

Subsequently, the latent-heat storage material is heated to a predetermined temperature and thus again undergoes phase transition from the solid phase to the liquid phase. When the latent-heat storage material in the liquid phase drops in temperature below the predetermined temperature, the latent-heat storage material does not undergo phase transition to the solid phase, but assumes a gel state. That is, the latent-heat storage material assumes the supercooled state. Accordingly, latent heat is stored in the latent-heat storage material.

According to the above-mentioned configuration, the electromagnetic-field generator applies an electromagnetic field to the supercooling canceler disposed in the latent-heat storage material container in the form of the closed container from the outside of the latent-heat-storage-material-accommodating section, which is an internal space of the latent-heat storage material container, thereby canceling the supercooled state of the latent-heat storage material. Thus, there can be suppressed leakage of the latent-heat storage material from the latent-heat storage material container and entry of foreign matter into the latent-heat-storage-material-accommodating section.

Also, the above-mentioned configuration can reliably cancel the supercooled state of the latent-heat storage material without use of an expensive material such as silver. Thus, the latent-heat storage device capable of reliably releasing the latent heat can be implemented with an inexpensive configuration.

An engine of the present invention is configured such that the temperature of a cooling medium can be rapidly increased during starting thereof. The engine comprises an engine block, a latent-heat storage material, a latent-heat storage material container, an electromagnetic-field generator, and a supercooling canceler. An engine start facilitation device of the present invention is configured so as to thermally facilitate starting of the engine. The engine start facilitation device comprises the latent-heat storage material, the latent-heat storage material container, the electromagnetic-field generator, and the supercooling canceler.

The engine block is a member for partially constituting a body section of the engine. A cooling-medium jacket serving as a path for the cooling medium is formed in the engine block. The latent-heat storage material container is disposed in the cooling-medium jacket. The electromagnetic-field generator is attached to the engine block.

According to the above-mentioned configuration, during cold start of the engine, the electromagnetic-field generator provided on the engine block generates a predetermined electromagnetic field at the outside of the latent-heat-storage-material-accommodating section. The electromagnetic field causes the supercooling canceler to mechanically operate in the latent-heat storage material container. As mentioned above, the mechanical operation of the supercooling canceler cancels the supercooled state of a small amount of the latent-heat storage material proximate to the supercooling canceler. As a result, small nuclei of the solid phase are formed. The formation of the small nuclei of the solid phase causes cancellation of the supercooled state to chain-react to the latent-heat storage material surrounding the nuclei, whereby the latent heat is released from the latent-heat storage material. After the engine is warmed up, heat generated through operation of the engine heats the latent-heat storage material to a predetermined temperature. This causes the latent-heat storage material to again undergo phase transition from the solid phase to the liquid phase. Subsequently, when the engine stops, and the temperature of the latent-heat storage material drops below the predetermined temperature, the latent-heat storage material in the supercooled state stores latent heat.

The above-mentioned configuration can suppress leakage of the latent-heat storage material from the latent-heat storage material container in the form of the closed container and entry of foreign matter into the latent-heat-storage-material-accommodating section. Particularly, entry of the cooling medium contained in the cooling-medium jacket into the latent-heat-storage-material-accommodating section can be suppressed. Also, the configuration can suppress mixing of the latent-heat storage material in the cooling medium contained in the cooling-medium jacket.

Also, the above-mentioned configuration can reliably cancel the supercooled state of the latent-heat storage material without use of an expensive material such as silver. Thus, the engine start facilitation device capable of thermally facilitating starting of the engine in an improved fashion can be implemented with an inexpensive configuration. Furthermore, the engine in which the temperature of the cooling medium rises in an improved fashion during starting thereof can be implemented with an inexpensive configuration.

The supercooling canceler may comprise a movable magnetic member and a trigger member. The movable magnetic member is disposed in the latent-heat-storage-material-accommodating section. The movable magnetic member is formed and disposed so as to move in the latent-heat-storage-material-accommodating section upon subjection to the electromagnetic field generated in the electromagnetic-field generator. The trigger member is formed and disposed so as to be biased or pressed in the latent-heat-storage-material-accommodating section as a result of movement of the movable magnetic member. Upon being biased or pressed, the trigger member cancels the supercooled state of the latent-heat storage material.

According to the above-mentioned configuration, the electromagnetic field (magnetic field) generated in the electromagnetic-field generator causes the movable magnetic member to move in the latent-heat-storage-material-accommodating section. The moving movable magnetic member biases or presses the trigger member in the latent-heat-storage-material-accommodating section. Upon being biased or pressed, the trigger member cancels the supercooled state of a small amount of the latent-heat storage material proximate thereto. As a result, small nuclei of the solid phase are formed. The formation of the small nuclei of the solid phase causes cancellation of the supercooled state to chain-react to the latent-heat storage material surrounding the nuclei, whereby the latent heat is released from the latent-heat storage material.

The above-mentioned configuration can reliably cancel the supercooled state of the latent-heat storage material. Thus, the latent heat can be reliably released from the latent-heat storage material by means of the simple device configuration.

The movable magnetic member and/or the trigger member may have a path for allowing passage of the latent-heat storage material. The above-mentioned configuration allows the latent-heat storage material to freely pass through the path when the latent-heat storage material is charged into the latent-heat-storage-material-accommodating section. Thus, the latent-heat storage material can fill a space around the movable magnetic member and/or the trigger member. That is, the latent-heat storage material can reliably reach a portion of the trigger member which contributes to formation of the above-mentioned nuclei. Thus, the release of latent heat can be more reliably performed.

Also, when the movable magnetic member moves in the latent-heat-storage-material-accommodating section, the latent-heat storage material around the movable magnetic member and/or the trigger member freely passes through the path. This lowers resistance of the latent-heat material to movement of the movable magnetic member, an operation of pressing the trigger member, elastic deformation of the trigger member, and the like. Accordingly, the electromagnetic-field generator can be of lower output; i.e., of a smaller-sized configuration. Also, the trigger member can be biased or pressed more reliably, so that the release of latent heat can be more reliably performed.

The trigger member may be designed to cancel the supercooled state of the latent-heat storage member through elastic deformation thereof.

According to the above-mentioned configuration, the electromagnetic field (magnetic field) generated in the electromagnetic-field generator causes the movable magnetic member to move in the latent-heat-storage-material-accommodating section. The moving movable magnetic member elastically deforms the trigger member in the latent-heat-storage-material-accommodating section. Upon being

ll elastically deformed, the trigger member cancels the supercooled state of a small amount of the latent-heat storage material proximate thereto. As a result, small nuclei of the solid phase are formed. The formation of the small nuclei of the solid phase causes cancellation of the supercooled state to chain-react to the latent-heat storage material surrounding the nuclei, whereby the latent heat is released from the latent-heat storage material.

According to the above-mentioned configuration, the latent heat can be reliably released from the latent-heat storage material with simple device configuration.

The latent-heat storage device of the present invention may further comprise a limiter portion for limiting elastic deformation of the trigger member.

According to the above-mentioned configuration, the electromagnetic field (magnetic field) generated in the electromagnetic-field generator causes the trigger member to be elastically deformed in the latent-heat-storage-material-accommodating section. At this time, the limiter portion limits elastic deformation of the trigger member.

The limiter portion effectively suppresses plastic deformation or cracking of the trigger member, which could otherwise result from excessive deformation of the trigger member.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a straight 3-cylinder engine according to an embodiment of the present invention taken perpendicular to the direction of cylinder arrangement for explaining the internal configuration of the engine. FIG. 2 is a perspective view of a latent-heat storage material container and a magnetic-field generator shown in FIG. 1.

FIG. 3 is a sectional view showing, on an enlarged scale, the magnetic-field generator shown in FIG. 1 and its periphery.

FIG. 4 is a sectional view showing, on an enlarged scale, the magnetic-field generator shown in FIG. 1 and its periphery.

FIG. 5(A) is a sectional view, on an enlarged scale, of a trigger member shown in FIG. 3.

FIG. 5(B) is a plan view of the trigger member shown in FIG. 5(A).

FIG. 6 is a pair of views showing a modification of the movable magnetic plate and the trigger member shown in FIG. 3, wherein FIG. 6(A) is a sectional view, and FIG. 6(B) is a plan view.

FIG. 7 is a pair of views showing another modification of the movable magnetic plate and the trigger member shown in FIG. 3, wherein FIG. 7(A) is a sectional view, and FIG. 7(B) is a plan view.

FIG. 8 is sectional view showing another modification of the latent-heat storage material container, the movable magnetic plate, and the trigger member shown in FIG. 3.

FIG. 9 is a sectional view showing a modification of the latent-heat storage material container, the movable magnetic plate, and the trigger member shown in FIG. 8.

FIG. 10 is a sectional view showing a modification of the magnetic-field generator shown in FIG. 3.

FIG. 11 is a view showing still another modification of the movable magnetic plate and the trigger member shown in FIG. 3.

FIG. 12 is a pair of views showing a modification of a seat portion and the trigger member shown in FIG. 11, wherein FIG. 12(A) is a sectional view, and FIG. 12(B) is a plan view.

FIG. 13 is a pair of views showing a modification of the movable magnetic plate shown in FIG. 12, wherein FIG. 13(A) is a sectional view of the movable magnetic plate and its periphery of the present modification, and FIG. 13(B) is a plan view of the movable magnetic plate.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention (the best mode contemplated by the applicant at the time of filing the present application) will next be described in detail with reference to the drawings. <General Configuration of Engine>

FIG. 1 is a sectional view of a straight 3-cylinder engine according to an embodiment of the present invention taken perpendicular to the direction of cylinder arrangement for explaining the internal configuration of the engine.

An engine 100 has an engine block 110. The engine block 110 is a member that partially constitutes a body section of the engine 100, and includes a cylinder head 111 and a cylinder block 112.

The cylinder head 111 has a cylinder head water jacket 111a, which is a flow path for cooling water for cooling the engine 100. The cylinder head water jacket 111 a is formed in the vicinity of an intake port 111b, which is a path for air-fuel mixture. The cylinder head water jacket 111a is also formed in the vicinity of an exhaust port 111c, which is a path for discharging exhaust gas. Furthermore, the cylinder head water jacket 111a is formed between an intake valve 111d and an exhaust valve 111e, the intake valve 111d and the exhaust valve 111e being disposed so as to open/close the intake port 111b and the exhaust port 111c, respectively.

The cylinder block 112 has a block bore 112a, which is a cylindrical through-hole. A thin-walled cylindrical cylinder liner 112b is inserted into the block bore 112a. The internal space of the cylinder liner 112b serves as a cylinder 112c. The cylinder 112c accommodates a piston 112d such that the piston 112d can reciprocate along the vertical direction in FIG. 1.

A cylinder block water jacket 112e, which is a flow path for the above-mentioned cooling water, is formed in an upper portion of the cylinder block 112. The cylinder block water jacket 112e surrounds an upper portion of the cylinder 112c and an upper portion of the cylinder liner 112b and assumes the form of a generally cylindrical, hollow portion.

A gasket 113 intervenes between the cylinder head 111 and the cylinder block 112. The gasket 113 has a through-hole 113a for allowing passage of the cooling water. The through-hole 113a allows the cooling water to flow between the cylinder block water jacket 112e and the cylinder head water jacket 111a.

A latent-heat storage material container 120 is designed to be disposed in the cylinder block water jacket 112e. The latent-heat storage material container 120 is accommodated in the cylinder block water jacket 112e while a clearance for allowing passage of the cooling water is formed between the same and the inner wall surface of the cylinder block water jacket 112e. The latent-heat storage container 120 assumes the form of a closed container that can contain a latent-heat storage material in a liquid-tight manner.

The latent-heat storage material is a substance that can retain latent heat therein in a supercooled state, in which the substance has a temperature lower than its melting point and maintains the gel phase, and that can release the latent heat therefrom through cancellation of the supercooled state with resultant phase transfer to the solid phase. That is, the latent-heat storage material is a substance having the following characteristic (supercooling characteristic): after the latent-heat storage material is heated in excess of its melting point and assumes the liquid phase, even when the latent-heat storage material is cooled below the melting point, the latent-heat storage material maintains the gel phase while retaining latent heat therein without undergoing phase change to the solid phase. Also, the latent-heat storage material is a substance that can release the latent heat therefrom at a temperature below its melting point through cancellation of the supercooled state being triggered by a certain external stimulus.

The latent-heat storage material used in the present embodiment is a substance having a melting point lower than the temperature (e.g., about 82⁰C) of the cooling water as measured after warming-up. Specifically, the latent-heat storage material is, for example, sodium acetate trihydrate (CH₃COONa SHbO; melting point 58°C). Even when cooled to about minus 2O⁰C to minus 3O⁰C, the latent-heat storage material can maintain the supercooled state.

A magnetic-field generator 130 is attached to the cylinder block 112. The magnetic-field generator 130 includes an electromagnet and is disposed so as to face the latent-heat storage material container 120. During cold start, the magnetic-field generator 130 is energized under control of an unillustrated engine control computer and generates a predetermined magnetic field.

FIG. 2 is a perspective view of the latent-heat storage material container 120 and the magnetic-field generator 130 shown in FIG. 1. FIGS. 3 and 4 are sectional views showing, on an enlarged scale, the magnetic-field generator 130 shown in FIG. 1 and its periphery. «Latent-Heat Storage Material Container»

Referring to FIG. 2, the latent-heat storage container 120 includes a container body 121 formed from a sheet of SUS304, which is a non-magnetic material. The container body 121 is composed of an outer side plate 121a, an inner side plate 121b, and horizontal plates 121c.

The outer side plate 121a and the inner side plate 121b are each formed into such a shape that three cylinders arranged in a row in an overlapping manner and are smoothly joined together. A space is formed between the outer side plate 121a and the inner side plate 121b for accommodating the latent-heat storage material. The horizontal plates 121c are connected to respective upper and lower ends of the outer side plate 121a and the inner side plate 121b.

Referring to FIGS. 2 and 3, the latent-heat storage material container 120 is accommodated in the cylinder block water jacket 112e such that a clearance for allowing passage of the cooling water is formed between the outer and inner side plates 121a and 121b and the inner wall surface of the cylinder block water jacket 112e.

A flat seat portion 122 is formed at a vertically central portion of the outer side plate 121a. The seat portion 122 is provided so as to face the magnetic-field generator 130. The seat portion 122 has an opening portion 122a in the form of a through-hole.

A seal plate 123 is joined to the outer surface of the seat portion 122 in such a manner as to cover the opening portion 122a in a liquid-tight manner. The seal plate 123 is also formed from a sheet of SUS304, which is a non-magnetic material. A trigger-accommodating portion 123a is formed at a central portion of the seal plate 123 in such a manner as to project toward the exterior of the latent-heat storage material container 120. The interior recess of the trigger-accommodating portion 123a serves as a space that can accommodate the latent-heat storage material.

The outer side plate 121a, the inner side plate 121b, and the horizontal plates 121c are joined together in a liquid-tight manner. A peripheral edge portion of the seal plate 123 and the outer surface of the seat portion 122 are joined together in a liquid-tight manner via a seal portion 124. As mentioned above, the latent-heat storage material container 120 is a closed container which internally has a latent-heat-storage-material-accommodating section 125 serving as a space for accommodating the latent-heat storage material in a liquid-tight manner. «Magnetic-Field Generator»

Referring to FIG. 3, the magnetic -field generator 130 is attached to a coil attachment portion 112f, which projects from the outer surface of the cylinder block 112. The magnetic-field generator 130 is configured so as to generate a magnetic field at the outside of the latent-heat-storage-material-accommodating section 125.

The magnetic-field generator 130 includes a coil 131 and a core 132, which constitute an electromagnet. The coil 131 and the core 132 are accommodated in an inner coil holder 133 having a generally cylindrical shape. The inner coil holder 133 is formed from SUS304, which is a non-magnetic material. An end portion of the inner coil holder 133 on a side toward the latent-heat storage material container 120 is formed into a shape that coincides with the profile of the trigger-accommodating portion 123a, so as to be able to abut the trigger-accommodating portion 123a. In other words, the end surface of the inner coil holder 133 on the side toward the latent-heat storage material container 120 is formed so as to come into contact with the outer surface of the trigger-accommodating portion 123a with the coil 131 and the core 132 being accommodated in the inner coil holder 133.

An outer coil holder 134 having a generally cylindrical shape is provided externally of the inner coil holder 133. The outer coil holder 134 internally supports the inner coil holder 133, thereby indirectly supporting the coil 131 and the core 132.

An end portion of the outer coil holder 134 on a far side from the latent-heat storage material container 120 is formed into an externally threaded portion. The externally threaded portion is threadingly engaged with an internally threaded portion of the coil attachment portion 112f, whereby the magnetic-field generator 130 is attached to the cylinder block 112. A fixing nut 135 is threadingly engaged with the externally threaded portion of the outer coil holder 134, whereby the magnetic-field generator 130 is fixed to the cylinder block 112 so as not to be detached from the cylinder block 112.

An O ring 136 intervenes between the outer coil holder 134 and the coil attachment portion 112f. The O ring 136 suppresses leakage of the cooling water from the cylinder block water jacket 112e to the exterior of the cylinder block 112 through a clearance between the outer coil holder 134 and the coil attachment portion 112f. «Supercooling canceler»

A movable magnetic plate 141 and a trigger member 142 are accommodated in the internal recess of the trigger-accommodating portion 123a formed at a central portion of the seal plate 123. In other words, the movable magnetic plate 141 and the trigger member 142 are disposed in the interior of the latent-heat-storage-material-accommodating section 125.

The movable magnetic plate 141 is formed from SUS430, which is a magnetic material, and has a disk-like shape. The movable magnetic plate 141 is disposed so as to face the core 132 of the magnetic-field generator 130 with the trigger member 142 and the seal plate 123 intervening therebetween. As shown in FIGS. 3 and 4, the movable magnetic plate 141 is formed and disposed so as to move in the latent-heat-storage-material-accommodating section 125 upon subjection to a magnetic field generated in the magnetic-field generator 130.

The trigger member 142 is disposed between the movable magnetic plate 141 and the seal plate 123. The trigger member 142 is a leaf spring member and is formed from a sheet of SUS304, which is a non-magnetic material. The trigger member 142 biases the movable magnetic plate 141 toward the seat portion 122.

The trigger member 142 is composed of a pan portion 142a and flange portions 142b. The pan portion 142a has a recess that opens toward the movable magnetic plate 141. That is, the pan portion 142a is formed in such a manner as to project toward the seal plate 123 (core 132) away from the movable magnetic plate 141. The flange portions 142b extend radially outward from the peripheral edge of the pan portion 142a.

The trigger member 142 is formed and disposed so as to be pressed toward the core 132 in the latent-heat-storage-material-accommodating section 125 as a result of movement of the movable magnetic member 141 toward the core 132 at the time when the coil 131 is energized. As shown in FIGS. 3 and 4, the trigger member 142 is designed such that, when the trigger member 142 is pressed as a result of movement of the movable magnetic plate 141, the pan portion 142a is elastically deformed.

Referring to FIGS. 3 and 4, the movable magnetic plate 141 and the trigger member 142, which constitute the supercooling canceler of the present invention, are designed to cancel the supercooled state of the latent-heat storage material by means of mechanically operating in the supercooled latent-heat storage material as a result of subjection to a magnetic field.

FIG. 5(A) is a sectional view, on an enlarged scale, of the trigger member 142 shown in FIG. 3. FIG. 5(B) is a plan view of the trigger member 142 shown in FIG. 5(A).

Referring to FIG. 5(B), a plurality of (four in the present embodiment) flange portions 142b project radially outward and each assume the form of a narrow tongue. A space between the adjacent flange portions 142b serves as a latent-heat storage material path 142c, which is a path for allowing passage of the latent-heat storage material. The pan portion 142a has a large number of notches 142d.

The trigger member 142 is designed to cancel the supercooled state of the latent-heat storage material proximate to the notches 142d provided on the pan portion 142a through elastic deformation of the pan portion 142a. <Operation of Engine of the Embodiment

The operation of the engine 100 having the above-mentioned configuration will next be described with reference to FIGS. 1 to 5.

Referring to FIG. 1 , when, after warming-up, the cooling water has a temperature higher than a predetermined warming-up end temperature (e.g., about 82°C), the entire latent-heat storage material (sodium acetate trihydrate (CH₃COONa-3H₂O; melting point 58⁰C) contained in the latent-heat storage material container 120 is heated above its melting point by the cooling water in the cylinder block water jacket 112e and thus assumes the liquid phase.

Subsequently, the engine 100 is stopped, and the cylinder block 112 and the cooling water in the cylinder block water jacket 112e drops in temperature to the outside air temperature or so. In this case, the latent-heat storage material does not undergo phase change to the solid phase, but is maintained in a state of the gel phase. That is, the latent-heat storage material retains latent heat therein by assuming the supercooled state.

Referring to FIG. 3, while the engine 100 is stopped, the coil 131 of the magnetic-field generator 130 is de-energized. In this case, the magnetic-field generator 130 does not generate a predetermined magnetic field for attracting the movable magnetic plate 141. Thus, while the engine 100 is stopped, as shown in FIG. 3, the trigger member 142 presses the movable magnetic plate 141 against the seat portion 122.

When the engine 100 is restarted, and warming-up is performed, the coil 131 is energized. Accordingly, the magnetic-field generator 130 which is located externally of the latent-heat-storage-material-accommodating section 125 generates the predetermined magnetic field for attracting the movable magnetic plate 141. Thus, as shown in FIG. 4, the movable magnetic plate 141 moves toward the core 132 against a biasing force of the trigger member 142.

As a result of the movement of the movable magnetic plate 141 , the movable magnetic plate 141 presses the flange portions 142b of the trigger member 142 toward the magnetic-field generator 130. This pressing causes the pan portion 142a to be elastically deformed. The elastic deformation of the pan portion 142a cancels the supercooled state of the latent-heat storage material proximate to the notches 142d (see FIG. 5), whereby small nuclei of the solid phase are generated. Contact of the nuclei with the surrounding latent-heat storage material in the supercooled state causes cancellation of the supercooled state to chain-react to the latent-heat storage material surrounding the nuclei.

Then, the cancellation of the supercooled state of the latent-heat storage material in the trigger-accommodating portion 123a spreads, through the opening portion 122a, to the entire latent-heat storage material stored in the space between the outer side plate 121a and the inner side plate 121b. In this manner, the supercooled state of the latent-heat storage material is canceled in a chain-reacting fashion, whereby the latent-heat storage material releases stored latent heat therefrom.

The latent heat released from the latent-heat storage material is transmitted to an upper portion of the cylinder block 112 via the cooling water around the latent-heat storage material container 120 in the cylinder block water jacket 112e. This facilitates warming-up during cold start.

The cooling water which is warmed by the latent heat released as mentioned above flows into the cylinder head water jacket 111a of the cylinder head 111, thereby warming regions proximate to the intake port 111b of the cylinder head 111 and the intake valve 111d. This suppresses, to the greatest possible extent, condensation of vaporized fuel and adhesion of condensed fuel to the wall of the intake port 111b and to the surface of the intake valve 111d, thereby suppressing variation in the air-fuel ratio of the air-fuel mixture to the greatest possible extent during cold start. <Effects of the Configuration of the Embodiment

The effects of the above-mentioned configuration of the present embodiment will next be described.

As shown in FIGS. 3 and 4, according to the configuration of the present embodiment, the movable magnetic plate 141 and the trigger member 142 are designed to cancel the supercooled state of the latent-heat storage material through mechanical operation thereof; i.e., pressing and elastic deformation effected by the pressing, and are accommodated in the latent-heat storage material container 120, which is a closed container. Being located externally of the latent-heat storage material container 120, which is a closed container; i.e., externally of the latent-heat-storage-material-accommodating section 125, which is a liquid-tight closed space, the magnetic-field generator 130 generates a magnetic field. The thus-generated magnetic field effects the above-mentioned pressing and elastic deformation.

The above-mentioned configuration can cancel the supercooled state of the latent-heat storage material without need to use such a structure that a rod member for driving the movable magnetic plate 141 and the trigger member 142 extends and moves in a reciprocating manner through the latent-heat storage material container 120. This can effectively suppress leakage of the latent-heat storage material from the latent-heat storage material container 120 as well as entry of the latent-heat storage material into the cylinder block water jacket 112e, which would otherwise result from the leakage. Also, entry of foreign matter; particularly, entry of the cooling water contained in the cylinder water jacket 111a, into the latent-heat-storage-material-accommodating section 125 can be effectively suppressed.

Thus, the configuration of the present embodiment can provide a latent-heat storage device capable of reliably releasing the latent heat therefrom, an engine start facilitation device capable of thermally facilitating starting of the engine 100 in an improved fashion, and the engine 100 in which the temperature of a cooling medium can be raised in an improved fashion during starting thereof, with simple device configuration and at low cost.

According to the configuration of the present embodiment, the trigger member 142 cancels the supercooled state of the latent-heat storage material through elastic deformation thereof. Therefore, the supercooled state of the latent-heat storage material can be reliably canceled without need to use an expensive material such as silver to form the trigger member 142.

According to the configuration of the present embodiment, the end surface of the inner coil holder 133 on the side toward the latent-heat storage material container 120 is formed so as to come into contact with the outer surface of the trigger-accommodating portion 123a with the coil 131 and the core 132 being accommodated in the inner coil holder 133. With the trigger-accommodating portion 123a in contact with the coil 131 , the core 132, and the inner coil holder 133, the movable magnetic plate 141 moves toward the core 132, thereby pressing the trigger member 142.

According to the above-mentioned configuration, the magnetically attractive force between the core 132 and the movable magnetic plate 141 is effectively used to elastically deform the trigger member 142. That is, wasteful use of the attractive force for, for example, deforming the trigger-accommodating portion 123a can be effectively suppressed. Therefore, the device configuration of the magnetic-field generator 130 can be simplified; for example, the size of the magnetic-field generator 130 can be reduced through use of the coil 131 having a fewer number of windings. Also, the magnetic-field generator 130 can be of low output and low power consumption. Furthermore, the trigger member 142 is reliably pressed by a small force. This enables more reliable release of the latent heat.

Referring to FIG. 5, according to the configuration of the present embodiment, the latent-heat storage material paths 142c for allowing passage of the latent-heat storage material are formed between the adjacent flange portions 142b.

According to the above-mentioned configuration, when the moving movable magnetic plate 141 presses the trigger member 142, the latent-heat storage material around the trigger member 142 freely passes through the latent-heat storage material paths 142c. Thus, resistance of the latent-heat storage material to elastic deformation of the trigger member 142 becomes relatively low. Accordingly, referring to FIGS. 3 and 4, the device configuration of the magnetic-field generator 130 can be more simplified, and the magnetic-field generator 130 can be of lower output and lower power consumption. Also, the trigger member 142 is more reliably pressed by a smaller force. This enables far more reliable release of the latent heat.

Referring to FIG. 1, according to the configuration of the present embodiment, the latent-heat storage material container 120 is accommodated in the cylinder block water jacket 112e.

Thus, according to the present embodiment, when the engine 100 is started, the cancellation of the supercooled state of the latent-heat storage material and the release of latent heat are performed within the cylinder block water jacket 112e. Accordingly, heat that is generated through cancellation of the supercooled state does not escape to the outside air, but is effectively transmitted to the cooling water contained in the cylinder block water jacket 112e and to the cylinder block 112.

According to the configuration of the present embodiment, a clearance for allowing passage of the cooling water is formed between the inner wall surface of the cylinder block water jacket 112e and the outer wall surface of the latent-heat storage material container 120.

In the above-mentioned configuration, when, during cold start, the latent heat is released from the latent-heat storage material, the released heat is transmitted to the cooling water that fills the clearance between the latent-heat storage material container 120 and the cylinder block water jacket 112e. Heat that is transmitted to the cooling water heats the cylinder block 112 to the greatest possible uniformity along the height direction of the cylinder 112c. This effectively suppresses friction loss in the cylinder block 112 which is undergoing warming-up. After warming-up, passage of the cooling water through the clearance between the inner wall surface of the cylinder block water jacket 112e and the outer wall surface of the latent-heat storage material container 120 prevents overheat of the latent-heat storage material contained in the latent-heat storage material container 120. <Modifications>

As mentioned previously, the above-described embodiment is a mere example of a typical embodiment of the present invention contemplated as the best mode by the applicant at the time of filing the present application. The above-described embodiment should not be construed as limiting the invention. Therefore, various modifications to the above-described embodiment are possible so long as the invention is not modified in essence.

Typical modifications will next be exemplified. In the following description of the modifications and the description of the above embodiment, members similar in structure and function are denoted by same reference numerals. The description of such members in relation to the above embodiment can be applied to the modifications so long as no technical inconsistencies are involved.

Needless to say, modifications are not limited to those exemplified below. Also, a plurality of modifications can be combined as appropriate so long as no technical inconsistencies are involved.

The above embodiment and the following modifications should not be construed as limiting the present invention (particularly, those component elements which constitute means for solving the problems to be solved by the invention and are illustrated in terms of operations and functions). (1) Application of the present invention is not limited to engines and automobiles as in the case of the above-mentioned embodiment. In application to engines, the present invention can be applied to not only straight-type engines such as straight 3-cylinder engines as in the case of the above-mentioned embodiment and straight 4-cylinder engines but also single-cylinder engines, V-type engines having a bank angle in excess of 0 degree and equal to or less than 180 degrees, and horizontally opposed engines.

In application of the present invention to engines having a plurality of cylinders, each cylinder may be provided with an independent latent-heat storage device (latent-heat storage material container 120, magnetic-field generator 130, movable magnetic plate 141 , and trigger member 142). Alternatively, only a certain cylinder may be provided with the latent-heat storage device.

(2) Examples of the latent-heat storage material include sodium acetate trihydrate (CHsCOONa ShbO); oxalic acid, magnesium acetate, manganese acetate, nickel sulfate, magnesium sulfate, copper sulfate, zinc sulfate, sodium thiosulfate, sodium sulfite, and hydrates thereof; naphthalene; palmitic acid; benzoic acid; high-purity paraffin; and mixtures thereof.

(3) Referring to FIG. 2, a plurality of seat portions 122, seal plates 123, and magnetic-field generators 130 may be provided. This enables more reliable release of the latent heat.

(4) Referring to FIG. 3, parting treatment may be conducted on the inner surface of the outer side plate 121a and the inner surface of the inner side plate 121b, which face the latent-heat-storage-material-accommodating section 125. Specifically, for example, the inner surfaces may be coated with a synthetic fluorine-containing resin. Alternatively, the container body 121 may be formed from a synthetic fluorine-containing resin.

The above-mentioned configuration can suppress, to the greatest possible extent, erroneous release of the latent heat before starting, which would otherwise result from generation of nuclei on the inner surfaces in a very-low-temperature environment during the engine being stopped.

(5) FIG. 6 is a pair of views showing a modification of the movable magnetic plate 141 and the trigger member 142 shown in FIG. 3, wherein FIG. 6(A) is a sectional view, and FIG. 6(B) is a plan view.

Referring to FIG. 6(A), leg portions 142e are formed at radially outer end portions of the flange portions 142b of the trigger member 142. The leg portions 142e project from the end portions of the flange portions 142b in a direction opposite the projecting direction of the pan portion 142a.

Referring to FIG. 6(B), elongated leg-portion-fixing holes 141a are formed in a peripheral portion of the movable magnetic plate 141. The leg-portion-fixing holes 141a receive the respective leg portions 142e, thereby retaining the trigger member 142.

According to the above-mentioned configuration, the movable magnetic plate 141 and the trigger member 142 are positioned. By virtue of this, during canceling of the supercooled state of the latent-heat storage material, the relative position between the movable magnetic plate 141 and the trigger member 142 is maintained substantially constant. Thus, even though the movable magnetic plate 141 and the trigger member 142 are repeatedly driven, the supercooled state of the latent-heat storage material can be reliably canceled at all times.

(6) FIG. 7 is a pair of views showing another modification of the movable magnetic plate 141 and the trigger member 142 shown in FIG. 3, wherein FIG. 7(A) is a sectional view, and FIG. 7(B) is a plan view.

Referring to FIG. 7(A), limiter protrusions 142f are provided on the respective flange portions 142b of the trigger member 142. The limiter protrusions 142f project in the same direction as the projecting direction of the pan portion 142a. The limiter protrusions 142f are bosses that are formed on the respective flange portions 142b by press-working.

According to the above-mentioned configuration, the limiter protrusions 142f limit elastic deformation of the pan portion 142a. Specifically, upon abutting the trigger-accommodating portion 123a (see FIG. 4), the limiter protrusions 142f suppress further elastic deformation of the pan portion 142a.

The configuration of the above-mentioned modification effectively suppresses plastic deformation or cracking of the pan portion 142a, which could otherwise result from excessive elastic deformation of the trigger member 142. Thus, even though the movable magnetic plate 141 and the trigger member 142 are repeatedly driven, the supercooled state of the latent-heat storage material can be consistently canceled. (7) FIG. 8 is a sectional view showing another modification of the latent-heat storage material container 120, the movable magnetic plate 141 , and the trigger member 142 shown in FIG. 3.

Referring to FIG. 8, the opening portion 122a formed in the outer side plate 121a of the container body 121 is a through-hole greater than the movable magnetic plate 141. That is, the opening portion 122a surrounds the circumference of the movable magnetic plate 141. A latent-heat storage material path 122b for allowing passage of the latent-heat storage material is formed between the opening circumference of the opening portion 122a and the circumference of the movable magnetic plate 141.

The inner side plate 121b has a flat seat portion 121b1 located in opposition to the seat portion 122. The seat portion 121 b1 faces the movable magnetic plate 141.

The trigger member 142 is disposed in such a manner that the pan portion 142a projects toward the movable magnetic plate 141 and that the flange portions 142b abut the trigger-accommodating portion 123a. The pan portion 142a has a positioning protrusion 142g at a central portion thereof as viewed in plane. The positioning protrusion 142g projects toward the movable magnetic plate 141.

The movable magnetic plate 141 has a positioning-protrusion-fixing hole 141b at a central portion thereof as viewed in plane. The positioning-protrusion-fixing hole 141b receives the positioning protrusion 142g.

According to the above-mentioned configuration, the positioning protrusion 142g and the positioning-protrusion-fixing hole 141b cooperatively set the relative position between the movable magnetic plate 141 and the trigger member 142. Thus, even though the movable magnetic plate 141 and the trigger member 142 are repeatedly driven, the supercooled state of the latent-heat storage material can be reliably canceled at all times.

When the latent-heat storage material is charged into the latent-heat-storage-material-accommodating section 125, the latent-heat storage material can freely pass through the latent-heat storage material path 122b. Thus, the latent-heat storage material can fill a space around the movable magnetic member 141 and the trigger member 142. That is, the latent-heat storage material can reliably reach a portion of the trigger member 142 which contributes to formation of the aforementioned nuclei. Thus, the release of latent heat can be more reliably performed.

Furthermore, when the movable magnetic member 141 moves in the latent-heat-storage-material-accommodating section 125, the latent-heat storage material around the movable magnetic member 141 freely passes through the latent-heat storage material path 122b. This lowers resistance of the latent-heat material to movement of the movable magnetic member 141. Accordingly, the electromagnetic-field generator 130 (see FIG. 3) can be of lower output; i.e., of a smaller-sized configuration. Additionally, the trigger member 142 can be biased or pressed more reliably, so that the release of latent heat can be more reliably performed. (8) FIG. 9 is a sectional view showing a modification of the latent-heat storage material container 120, the movable magnetic plate 141, and the trigger member 142 shown in FIG. 8.

Referring to FIG. 9, according to the present modification, the movable magnetic plate 141 has a positioning protrusion 141c. The positioning protrusion 141c projects toward the seal plate 123. Also, according to the present embodiment, the trigger member 142 has a positioning-protrusion-fixing hole 142h.

The above-mentioned configuration yields actions and effects similar to those of the modification which has been described with reference to FIG. 8. Furthermore, according to the present modification, the positioning protrusion 141c limits movement of the movable magnetic plate 141. Accordingly, the positioning protrusion 141c also limits deformation of the trigger member 142. This effectively suppresses plastic deformation or the like of the trigger member 142, which could otherwise result from excessive elastic deformation of the trigger member 142.

(9) FIG. 10 is a sectional view showing a modification of the magnetic-field generator 130 shown in FIG. 3. The magnetic-field generator 130 of the present embodiment has an actuator 137 and a permanent magnet 138 in place of the coil 131 and the core 132 shown in FIG. 3.

The actuator 137 includes a motor or a solenoid. Upon being energized, the actuator 137 advances/retreats a movable shaft 137a. The permanent magnet 138 is fixed to an end of the movable shaft 137a.

According to the above-mentioned configuration, when, during cold start, the actuator 137 is driven, the permanent magnet 138 moves toward the movable magnetic plate 141. This causes the movable magnetic plate 141 to move toward the permanent magnet 138 through attraction by the permanent magnet 138. The moving movable magnetic plate 141 presses the trigger member 142, thereby canceling the supercooled state of the latent-heat storage material around the trigger member 142.

(10) FIG. 11 is a view showing still another modification of the movable magnetic plate 141 and the trigger member 142 shown in FIG. 3.

Referring to FIG. 11 , the movable magnetic plate 141 is disposed externally of the seat portion 122. The movable magnetic plate 141 has a trigger penetrant shaft 143, which projects from its side facing the seat portion 122 into the space between the outer side plate 121a and the inner side plate 121b. The trigger penetrant shaft 143 is formed integrally with the movable magnetic plate 141.

The trigger member 142 is disposed in the space between the outer side plate 121a and the inner side plate 121b. That is, the trigger member 142 is disposed in such a manner that the flange portions 142b thereof are in contact with the inner surface of the seat portion 122 (the surface of the seat portion 122 on a side toward the inner side plate 121b). The trigger member 142 is disposed in such a manner that the pan portion 142a projects into the space between the outer side plate 121a and the inner side plate 121b.

The pan portion 142a has a central projecting portion 142k which is located at a central portion thereof as viewed in plane. The central projecting portion 142k projects toward the inner side plate 121b. The central projecting portion 142k has a through-hole through which the trigger penetrant shaft 143 is inserted. A stopper 144 has an outside diameter greater than the through-hole in the central projecting portion 142k. The stopper 144 is fixed to an end portion of the trigger penetrant shaft 143 so as to prevent the trigger penetrant shaft 143 from coming off the through-hole in the central projecting portion 142k.

According to the above-mentioned configuration, when the coil 131 is energized, the magnetic-field generator 130 generates the aforementioned predetermined magnetic field for attracting the movable magnetic plate 141. Upon the movable magnetic plate 141 being attracted by the magnetic field, the trigger penetrant shaft 143 and the stopper 144 are also urged to move toward the magnetic-field generator 130. This causes the central projecting portion 142k of the trigger member 142 to be biased upward in FIG. 11. As a result of the central projecting portion 142k being biased, a region of the pan portion 142a of the trigger member 142 between the central projecting portion 142k and the flange portions 142b is elastically deformed. This elastic deformation of the pan portion 142a cancels the supercooled state of the latent-heat storage material proximate to the pan portion 142a and located internally of the opening portion 122a within the latent-heat-storage-material-accommodating section 125.

According to the above-mentioned configuration, the trigger member 142 generates the nuclei within the space between the outer side plate 121a and the inner side plate 121b. Accordingly, the generation of nuclei promptly chain-reacts to most of the latent-heat storage material stored in the space between the outer side plate 121a and the inner side plate 121b. Therefore, according to the configuration, the latent heat is released more promptly and reliably.

(11) FIG. 12 is a pair of views showing a modification of the seat portion 122 and the trigger member 142 shown in FIG. 11, wherein FIG. 12(A) is a sectional view, and FIG. 12(B) is a plan view.

In the present modification, the trigger member 142 including the flange portion 142b assumes the form of a disk having neither cut portions nor joined portions. In other words, the trigger member 142 of the present modification does not have a path for allowing passage of the latent-heat storage material.

In the present modification, the seat portion 122 has a plurality of latent-heat storage material paths 122b. The latent-heat storage material paths 122b are grooves that radiate from the opening portion 122a. Distal end portions of the latent-heat storage material paths 122b open at positions located radially outward of the flange portion 142b of the trigger member 142.

According to the above-mentioned configuration, during movement of the movable magnetic plate 141 , the latent-heat storage material can freely pass through the latent-heat storage material paths 122b. Thus, the movable magnetic plate 141 can smoothly move in the trigger-accommodating portion 123a by virtue of low resistance. Accordingly, referring to FIGS. 3 and 4, the device configuration of the magnetic-field generator 130 can be more simplified, and the magnetic-field generator 130 can be of lower output and lower power consumption. Also, the trigger member 142 is more reliably pressed by a smaller force. This enables far more reliable release of the latent heat.

(12) FIG. 13 is a pair of views showing a modification of the movable magnetic plate 141 shown in FIG. 12, wherein FIG. 13(A) is a sectional view of the movable magnetic plate 141 and its periphery of the present modification, and FIG. 13(B) is a plan view of the movable magnetic plate 141.

In the present modification, the movable magnetic plate 141 has through-holes 141d and cutouts 141e. As shown in FIG. 13(B), the cutouts 141e are formed in a peripheral edge portion of the movable magnetic plate 141. The through-holes 141d and the cutouts 141e serve as latent-heat storage material paths for free passage of the latent-heat storage material.

According to the above-mentioned configuration, during movement of the movable magnetic plate 141 , the latent-heat storage material can freely pass through the through-holes 141d and the cutouts 141e. Thus, the movable magnetic plate 141 can smoothly move in the trigger-accommodating portion 123a by virtue of low resistance.

(13) In the embodiment and modifications described above, the magnetic-field generator 130 is provided on the cylinder block 112 and is located externally of the latent-heat storage material container 120. However, the magnetic-field generator 130 may be provided on the latent-heat storage material container 120.

(14) The movable magnetic plate 141 and the trigger member 142 can be integrated together. Specifically, at least a portion of the trigger member 142 is formed from a magnetic material, whereby the movable magnetic plate 141 can be eliminated.

(15) In the embodiment and modifications described above, the magnetic member in the latent-heat-storage-material-accommodating section 125 is moved by a magnetic force, thereby canceling the supercooled state of the latent-heat storage material.

However, the present invention is not limited thereto. For example, an electric-field generator may replace the magnetic-field generator 130. In this case, the latent-heat-storage-material-accommodating section 125 accommodates a member that can mechanically operate in accordance with an electric field generated by the electric-field generator.

(16) Those component elements which constitute means for solving the problems to be solved by the invention and are illustrated in terms of operations and functions include specific structures disclosed in the above-described embodiment and modifications, and any other structures that can implement the operations and functions.

INDUSTRIAL APPLICABILITY

The present invention can be applied to a latent-heat storage device for retaining latent heat therein in a releasable manner, to an engine start facilitation device for thermally facilitating starting of an engine, and to an engine in which the temperature of a cooling medium can be rapidly increased during starting thereof.

Claims

1. A latent-heat storage device for retaining latent heat therein in a releasable manner, comprising: a latent-heat storage material for retaining latent heat therein in a supercooled state and releasing the latent heat therefrom through cancellation of the supercooled state; a latent-heat storage material container in the form of a closed container internally having a latent-heat-storage-material-accommodating section which is a space for accommodating the latent-heat storage material in a liquid-tight manner; an electromagnetic-field generator for generating an electromagnetic field at the outside of the latent-heat-storage-material-accommodating section; and a supercooling canceler disposed in the latent-heat storage material container and adapted to cancel the supercooled state of the latent-heat storage material through mechanical operation thereof in the latent-heat storage material in the supercooled state, the mechanical operation being effected by the electromagnetic field.

2. A latent-heat storage device according to claim 1 , wherein the supercooling canceler comprises: a movable magnetic member which is disposed in the latent-heat-storage-material-accommodating section and which moves in the latent-heat-storage-material-accommodating section upon subjection to the electromagnetic field generated in the electromagnetic-field generator; and a trigger member which is formed and disposed so as to be biased or pressed in the latent-heat-storage-material-accommodating section as a result of movement of the movable magnetic member and which, when biased or pressed, cancels the supercooled state of the latent-heat storage material.

3. A latent-heat storage device according to claim 2, wherein the movable magnetic member and/or the trigger member has a path for allowing passage of the latent-heat storage material.

4. A latent-heat storage device according to claim 2 or 3, wherein the trigger member cancels the supercooled state of the latent-heat storage member through elastic deformation thereof.

5. A latent-heat storage device according to claim 4, further comprising a limiter portion for limiting elastic deformation of the trigger member.

6. An engine start facilitation device for thermally facilitating starting of an engine, comprising: a latent-heat storage material for retaining latent heat therein in a supercooled state and releasing the latent heat therefrom through cancellation of the supercooled state; a latent-heat storage material container in the form of a closed container internally having a latent-heat-storage-material-accommodating section which is a space for accommodating the latent-heat storage material in a liquid-tight manner, the latent-heat storage material container being disposed in a cooling-medium jacket which is a cooling-medium path formed in an engine block partially constituting a body section of the engine; an electromagnetic-field generator for generating an electromagnetic field at the outside of the latent-heat-storage-material-accommodating section, the electromagnetic-field generator being attached to the engine block; and a supercooling canceler disposed in the latent-heat storage material container and adapted to cancel the supercooled state of the latent-heat storage material through mechanical operation thereof in the latent-heat storage material in the supercooled state, the mechanical operation being effected by the electromagnetic field.

7. An engine start facilitation device according to claim 6, wherein the supercooling canceler comprises: a movable magnetic member which is disposed in the latent-heat-storage-material-accommodating section and which moves in the latent-heat-storage-material-accommodating section upon subjection to the electromagnetic field generated in the electromagnetic-field generator; and a trigger member which is formed and disposed so as to be biased or pressed in the latent-heat-storage-material-accommodating section as a result of movement of the movable magnetic member and which, when biased or pressed, cancels the supercooled state of the latent-heat storage material.

8. An engine start facilitation device according to claim 7, wherein the movable magnetic member and/or the trigger member has a path for allowing passage of the latent-heat storage material.

9. An engine start facilitation device according to claim 7 or 8, wherein the trigger member cancels the supercooled state of the latent-heat storage member through elastic deformation thereof.

10. An engine start facilitation device according to claim 9, further comprising a limiter portion for limiting elastic deformation of the trigger member.

11. An engine in which temperature of a cooling medium can be rapidly increased during starting thereof, comprising: an engine block in which a cooling-medium jacket serving as a path for the cooling medium is formed and which partially constitutes a body section of the engine; a latent-heat storage material for retaining latent heat therein in a supercooled state and releasing the latent heat therefrom through cancellation of the supercooled state; a latent-heat storage material container in the form of a closed container internally having a latent-heat-storage-material-accommodating section which is a space for accommodating the latent-heat storage material in a liquid-tight manner, the latent-heat storage material container being disposed in the cooling-medium jacket; an electromagnetic-field generator provided on the engine block and adapted to generate an electromagnetic field at the outside of the latent-heat-storage-material-accommodating section; and a supercooling canceler disposed in the latent-heat storage material container and adapted to cancel the supercooled state of the latent-heat storage material through mechanical operation thereof in the latent-heat storage material in the supercooled state, the mechanical operation being effected by the electromagnetic field.

12. An engine according to claim 11, wherein the supercooling canceler comprises: a movable magnetic member which is disposed in the latent-heat-storage-material-accommodating section and which moves in the latent-heat-storage-material-accommodating section upon subjection to the electromagnetic field generated in the electromagnetic-field generator; and a trigger member which is formed and disposed so as to be biased or pressed in the latent-heat-storage-material-accommodating section as a result of movement of the movable magnetic member and which, when biased or pressed, cancels the supercooled state of the latent-heat storage material.

13. An engine according to claim 12, wherein the movable magnetic member and/or the trigger member has a path for allowing passage of the latent-heat storage material.

14. An engine according to claim 12 or 13, wherein the trigger member cancels the supercooled state of the latent-heat storage member through elastic deformation thereof.

15. An engine according to claim 14, further comprising a limiter portion for limiting elastic deformation of the trigger member.