JP6051888B2 - engine - Google Patents

Description

  The present invention relates to an internal combustion engine (hereinafter referred to as “engine”), and in particular, to an engine having a function capable of switching between heat dissipation and heat insulation from an engine separately from an engine cooling device.

  Insert one end of the heat pipe that transports heat as the latent heat of the working fluid into the inside of the case where the internal atmosphere is high, while ensuring airtightness, and connect the other end of the heat pipe to the outside of the case. There is a heat pipe type air cooling device exposed to (see Patent Document 1).

JP-A-9-273877

  By the way, as an effort to reduce the weight of the engine, in place of the cast iron cylinder block, a separate cast iron liner is cast or an aluminum alloy member cylinder block into which the liner is press-fitted, or an aluminum alloy member upper oil. Bread has appeared.

  However, these measures alone are not sufficient for reducing the weight of the engine. In the technique of the above-mentioned Patent Document 1, there is no description about the weight reduction of the engine.

  Therefore, it is conceivable to replace a part of the structure constituting the engine with a polymer compound material having a specific gravity smaller than that of the metal material. In this case, since the polymer compound material has a lower thermal conductivity than the metal material, the heat insulation of the engine is improved accordingly. Then, when the capacity of the water pump and the capacity of the oil pump (the capacity of the cooling device and the lubrication device) are the same as before, the coolant temperature and the oil temperature are higher than before, especially when the engine is under a heavy load, and the bearing inside the engine Problems such as seizure occur.

  Accordingly, an object of the present invention is to provide an engine that can reduce the weight of the engine and keep the cooling water temperature and the oil temperature at the same level as the conventional one.

In the engine of the present invention, at least a part of the engine structure is composed of a metal member that is in contact with the outside air and a polymer compound member that is disposed inside the engine from the metal member . And it has the heat-transfer member arrange | positioned so that the said metal member and the said high molecular compound member may be connected.

  According to the present invention, by replacing a part of the structure constituting the engine with the polymer compound member, the metal member and the polymer compound member are compared with the structure of the metal uniform member like the conventional engine. It is possible to reduce the weight of the structure constituting the engine by an amount corresponding to the specific gravity difference between them and the volume of the polymer compound member. In addition, since a heat exchangeable structure is configured by arranging the heat transfer member, the cooling water temperature and oil temperature do not become too high, especially when the engine is under high load, and the cooling water temperature and oil temperature are the same level as before. It is possible to fit in. As a result, seizure of the bearing portion inside the engine can be avoided.

It is a schematic block diagram of the cooling device of the engine of 1st Embodiment of this invention. It is a schematic perspective view of an engine. It is a longitudinal cross-sectional view of the engine of 1st Embodiment. It is a characteristic view which shows the state change of the heat storage material accommodated in the heat-transfer member. It is a characteristic view which shows the state change of the thermal storage material accommodated in the 2nd heat-transfer member. It is an expanded sectional view of the A section of FIG. It is an expanded sectional view of the B section of FIG. It is a longitudinal cross-sectional view of the engine of 2nd Embodiment. It is a longitudinal cross-sectional view of the engine of 3rd Embodiment. It is an expanded sectional view of the C section of FIG. It is a schematic perspective view of the lower oil pan of 3rd Embodiment. It is a longitudinal cross-sectional view of the engine of 4th Embodiment. It is a longitudinal cross-sectional view of the engine of 5th Embodiment. It is a longitudinal cross-sectional view of the engine of 6th Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic configuration diagram of an engine cooling device 2 according to a first embodiment of the present invention. In FIG. 1, the cooling water of about 80 to 90 ° C. exiting the engine 1 flows separately into a cooling water passage 4 that passes through the radiator 3 and a bypass cooling water passage 5 that bypasses the radiator 3. Thereafter, the two flows are merged again by the thermostat valve 6 that determines the distribution of the flow rate of the cooling water flowing through both the passages 4 and 5, and then returns to the engine 1 via the water pump 7. The thermostat valve 6 is a three-way valve that controls the flow rate of coolant supplied to the radiator 3 in accordance with the coolant temperature, and has a valve body 6a, two inlet ports 6b and 6c, and one outlet port 6d. Yes. A cooling water passage 4 that passes through the radiator 3 and a cooling water passage 5 that bypasses the radiator 3 are connected to the two inlet ports 6b and 6c. The thermostat valve 6 supplies the cooling water passage 4 to the radiator 3 according to the cooling water temperature. The coolant flow rate is increased or decreased to maintain the coolant temperature appropriately.

  For example, when the temperature of the cooling water flowing through the thermostat valve 6 is less than a predetermined value as in the cold start of the engine, warming the engine 1 improves the efficiency of the engine 1. For this reason, at the time of engine cold start, the valve body 6a shuts off the inlet port 6b and does not flow the cooling water to the radiator 3, but the inlet port 6c and the outlet port 6d are communicated to flow the cooling water to the bypass cooling water passage 5. This prevents the engine 1 from being cooled. On the other hand, knocking must be avoided in a high temperature range where the temperature of the cooling water flowing through the thermostat valve 6 is equal to or higher than a predetermined value as in a high load state. For this reason, at the time of high load, the inlet port 6b is opened by the valve body 6a, and the inlet port 6b and the outlet port 6d are communicated. As a result, cooling water flows through the radiator 3, and the cooling water cooled by the radiator 3 is supplied to the engine 1 to cool the engine 1.

  Hereinafter, the temperature at which the thermostat valve 6 is opened is referred to as “valve opening temperature”. Normally, when the coolant temperature is within a certain temperature range, the thermostat valve 6 gradually increases in opening degree (amount flowing to the radiator side) as the coolant temperature rises to reach a fully open state. . Hereinafter, the valve opening temperature means a representative temperature such as a temperature at which opening begins, a temperature at which the valve opens fully, or an average value thereof.

  2 is a schematic perspective view of the engine 1, and FIG. 3 is a longitudinal sectional view of the engine 1 cut along a plane orthogonal to the longitudinal direction of the serial type engine 1 shown in FIG. In FIG. 2, the cylinder head is omitted. The outline of the engine 1 will be described first with reference to FIG. 3. The engine 1 includes a cylinder block 11, a cylinder head 61 positioned above the cylinder block 11, and an oil pan (31, 51) positioned below the cylinder block 11. It is composed of

  A cylinder block 11 formed of an aluminum die-cast member is composed of a substantially rectangular parallelepiped cylinder bore portion 12 and a skirt portion 15. In the cylinder bore portion 12, cylinders 13 penetrating in the vertical direction are formed in a row in the longitudinal direction of the engine 1, and a water jacket 14 is formed around each cylinder 13. A skirt portion 15 formed below the cylinder bore portion 12 opens downward.

  The oil pan is composed of an upper oil pan 31 positioned relatively above and a lower oil pan 51 positioned relatively below. The upper oil pan 31 formed of an aluminum alloy member and the cylinder block 11 are fastened by bolts (not shown), and the crank chamber 32 that houses the crankshaft is formed by the upper oil pan 31 and the skirt portion 15 of the cylinder block 11. Has been. Inside the crank chamber 32 is housed a crankshaft (not shown) connected via a connecting rod and a piston sliding on the cylinder 13. The cylinder block 11 is provided with a bearing portion of a crankshaft. For example, a plurality of main bearing caps are fixed from below in the engine longitudinal direction, and a half-shaped main bearing (lower) is accommodated in the main bearing cap. On the other hand, a half-shaped main bearing (upper) is also stored on the lower surface of the cylinder block facing the mounting position of the main bearing, and the crankshaft is rotatably supported at a plurality of locations by the pair of half-shaped main bearings.

  The lower oil pan 51 is fastened to the upper oil pan 31 by bolts (not shown). The upper oil pan 31 not only functions as a flange portion to which the lower oil pan 51 is attached, but also serves to increase the bending and torsional rigidity of the entire cylinder block 11. The lower oil pan 51 is formed in a shallow dish shape only with a polymer compound member, and lubricating oil is stored here. This lubricating oil is supplied to each lubricating part such as the pair of half-split main bearings by an oil pump (not shown), thereby preventing seizure from occurring in the bearing part inside the engine. The oil pump is driven by a crankshaft. The water pump 7 is also driven by the crankshaft.

  The cylinder head 61 and the cylinder block 11 formed of an aluminum alloy member are joined via a cylinder head gasket (not shown) and fastened by a bolt (not shown). In the cylinder head 61, a combustion chamber 62, an intake port 63, an exhaust port 64, a water jacket 65, and the like are formed. The water jacket 65 and the water jacket 14 provided in the cylinder bore portion 12 communicate with each other, and constitute a part of the cooling water passage of the engine 1.

  As an effort to reduce the weight of the engine 1, instead of a cast iron cylinder block, a separate cast iron liner is cast, or a cylinder block of an aluminum alloy member into which the liner is press-fitted or an upper of the aluminum alloy member is used. An oil pan is appearing. However, in order to control the vehicle equipped with the engine 1 stably in the future, it is necessary to reduce the weight of the entire vehicle, and it is necessary to reduce the weight of the engine 1 that can follow the weight reduction of the vehicle. In this respect, it is still insufficient to simply form the cylinder block 11 and the upper oil pan 31 with an aluminum die cast member or an aluminum alloy member.

  Therefore, in the first embodiment of the present invention, a structure in which a part of the aluminum die cast member and the aluminum alloy part of the cylinder head 11 and the upper oil pan 31 is housed in a polymer compound member and the outside is covered with an aluminum alloy member. Replace with (22, 41). This will be described with reference to FIG. 3. A part of the aluminum die cast part of the cylinder block 11 is replaced with the cylinder block structure 22, and a part of the aluminum alloy part of the upper oil pan 31 is replaced with the upper oil pan structure 41. That is, if the cylinder block 11 is roughly divided into a cylindrical inner portion 21 and an outer portion located on the outer periphery thereof, the outer portion is replaced with the cylinder block structure 22. Here, the range of the cylinder block structure 22 is shown surrounded by a one-dot chain line. In this case, even if a part of the aluminum die cast part of the cylinder block 11 is replaced by the cylinder block structure 22, the rigidity of the cylinder block 11 as a whole is not significantly reduced (that is, it is accommodated by the allowable range of rigidity reduction).

  The cylinder block structure 22 includes a hollow metal member 23 and a polymer compound member 24. The hollow metal member 23 is composed of an outer peripheral member 23a on the side farther from the cylinder 13, an inner peripheral member 23b on the side closer to the cylinder 13, and a member (not shown) connecting them, and the whole is made of, for example, an aluminum die cast member. Form. Since the inner peripheral member 23b is also an aluminum die-cast member, there is actually no boundary between the inner portion 21 of the cylinder block 11 and the inner peripheral member 23b, and the inner portion 21 of the cylinder block 11 and the inner peripheral member 23b are integrated.

  Similarly, a part of the aluminum alloy part of the upper oil pan 31 is replaced with the upper oil pan structure 41. Here, the range of the upper oil pan structure 41 is shown surrounded by a two-dot chain line. In this case, even if a part of the aluminum alloy portion of the upper oil tank 31 is replaced by the upper oil tank structure 41, the rigidity of the upper oil tank 31 as a whole is not significantly reduced (that is, it is accommodated by a reduction in the allowable range of rigidity). )

  The upper oil pan structure 41 includes a hollow metal member 42 and a polymer compound member 43. The hollow metal member 42 is composed of an outer peripheral member 42a on the side farther from the crank chamber 32, an inner peripheral member 42b on the side closer to the crank chamber 32, and a member (not shown) connecting them, for example, an aluminum alloy as a whole. Form with members.

  In FIG. 3, the hollow metal member 22 of the cylinder block structure 22 and the hollow metal member 42 of the upper oil pan structure 41 are shown as separate bodies, but they may be provided integrally.

  A polymer compound member 24 is accommodated in the one hollow metal member 23, and a polymer compound member 43 is accommodated in the other hollow metal member 42. As the polymer compound members 24 and 43, a foamed resin that is light and excellent in heat insulation is desirable. Here, the foamed resin refers to a synthetic resin containing countless fine bubbles inside. The material is not limited to the foamed resin, and any polymer compound material that is lighter than a metal material (aluminum die-cast member or aluminum alloy member) may be used.

  Accordingly, as a whole of the cylinder block 11, a part of the metal portion formed by the aluminum die cast member is replaced by the polymer compound member 24. If the high molecular compound member 24 is compared with the aluminum die cast member, the specific gravity is smaller in the high molecular compound member 24. Therefore, the cylinder block 11 is reduced in weight by the amount of the specific gravity multiplied by the volume of the high molecular compound member 24. Will be. Similarly, as a whole of the upper oil pan 31, a part of the metal part formed of the aluminum alloy member is replaced with the polymer compound member 43. If the high molecular compound member 43 is compared with the aluminum alloy member, the specific gravity is smaller in the high molecular compound member 43. Therefore, the upper oil pan 31 is lighter by the amount obtained by multiplying the specific gravity difference by the volume of the high molecular compound member 43. Will be converted.

  In FIG. 3, the cylinder block structure 22 is provided around the cylinder 13, but the portion where the cylinder block structure 22 is provided is not limited to the circumference of the cylinder 13. The number and shape of the cylinder block structures 22 and the positions where the cylinder block structures 22 are provided are arbitrary. For example, the cylinder block structure 22 may be provided only for a specific cylinder or may be provided for each cylinder 13. It is good also as an integral shape which connected the cylinder block structure provided for every cylinder 13. FIG. Similarly, the number and shape of the upper oil pan structures 41 and the positions where the upper oil pan structures 41 are provided are also arbitrary. For example, the upper oil pan structure 41 may be provided only at a specific portion of the upper oil pan 31 or may be provided over a wide range of the upper oil pan 31. The upper oil pan structure 41 may be provided not only on both side surfaces in the longitudinal direction of the engine 1 but also only on one side surface.

  On the other hand, replacing the aluminum die cast part or part of the aluminum alloy part of the cylinder block 11 or the upper oil pan 31 with the hollow metal members 23 and 42 containing the polymer compound members 24 and 43 is from the viewpoint of heat transfer. It may be disadvantageous. That is, when the engine actively generates heat and reaches a high temperature as in a high load, it is desirable to release a large amount of heat from the cylinder block structure 22 and the upper oil pan structure 41 to the outside air accordingly. At this time, if the polymer compound members 24 and 43 inside the structures 22 and 41 function as heat insulating members, the engine 1 cannot be cooled down especially when the engine is under a high load. At this time, the cooling water temperature and the oil temperature are higher than those in the case where the cylinder block structure 22 and the upper oil pan structure 41 are not provided, and problems such as seizure occur in the bearing portion inside the engine.

  Therefore, in the present embodiment, the outer peripheral member 23a of the hollow metal members 23 and 42 is provided in order to balance the heat insulation that prevents the heat of the engine 1 from being taken away by the outside air and the heat dissipation that releases the heat from the engine 1 to the outside air. , 42 a and the polymer compound members 24, 43 are arranged so as to connect the heat transfer member 101. That is, in the cylinder block structure 22, the plurality of heat transfer members 101 are arranged so as to connect the outer peripheral member 23 a of the hollow metal member 23 and the polymer compound member 24. Similarly, in the upper oil pan structure 41, the plurality of heat transfer members 101 are arranged so as to connect the outer peripheral member 42 a of the hollow metal member 42 and the polymer compound member 43. One end of the heat transfer member 101 protrudes (exposes) from the outer surface of the structures 22 and 41 to the outside of the engine. This is to improve the heat dissipation performance from the engine via the heat transfer member 101 especially when the engine is heavily loaded. Note that FIG. 3 does not show the internal state of each heat transfer member 101.

  Here, the heat transfer characteristic of the heat transfer member 101 changes depending on the temperature of the heat transfer member 101 itself so that the heat transfer becomes easier as the temperature of the heat transfer member 101 itself increases. Specifically, each heat transfer member 101 arranged in the two structures 22 and 41 is configured by enclosing a heat storage material 103 (medium) such as paraffin wax in the hollow metal member 102 as shown in FIG. 4A. ing. For this reason, the ease of movement of the heat storage material 103 in the hollow metal member 102 changes depending on the temperature of the heat transfer member 101 itself, whereby the heat transfer characteristics of the heat transfer member 101 change.

  Specifically, the heat storage material 103 is solid when the temperature is equal to or lower than a predetermined temperature that is the melting point of the heat storage material 103, and changes in phase to become liquid when the temperature exceeds the predetermined temperature. That is, when the heat storage material 103 is in a solid state, it is difficult to move in the hollow metal member 102 (the amount of movement of the heat storage material 103 is relatively reduced). When the movement amount of the heat storage material 103 decreases, the heat movement amount also decreases. On the other hand, when the heat storage material 103 is in a liquid state, the heat storage material 103 is easily moved in the hollow metal member 102 (the amount of movement of the heat storage material 103 is relatively increased). The amount of heat transfer increases as the amount of movement of the heat storage material 103 increases.

  The material of the hollow metal member 102 of the heat transfer member 101 is preferably a material (for example, tin) having better thermal conductivity than the aluminum die-cast member or the aluminum alloy member that constitutes the main body of the cylinder block 11 or the upper oil pan 31.

  Here, as a representative of the heat transfer member 101 disposed in the cylinder block structure 22, a mechanism of switching between heat dissipation and heat insulation by the heat transfer member 101 will be described with reference to FIG. 4A. The functions of the heat transfer members 101 are the same between the heat transfer members 101 arranged in the cylinder block structure 22 and the heat transfer members 101 arranged in the upper oil pan structure 41.

  FIG. 4A shows a heat transfer member in three different states (a state where the engine is warmed up from the top of FIG. 4A, a state where the engine is operating at a high load, and a state where the vehicle equipped with the engine is stopped). It shows how the heat storage material 103 housed in 101 changes its state. In FIG. 4A, the vertical direction is the vertical direction, and the overall shape of the heat transfer member 101 is a capsule shape that is long in the horizontal direction, and heat transfer is performed so as to connect the outer peripheral member 23 a of the hollow metal member 23 and the polymer compound member 24. A member 101 is disposed. Furthermore, it is assumed that one end (the left end in FIG. 4A) of the heat transfer member 101 protrudes from the outer surface 22a of the cylinder block structure 22 to the outside air.

  First, (a) shown in the upper part of FIG. 4A shows a state where the engine is started in a cold state and warmed up. The engine cooling water during warm-up is, for example, about 60 ° C. At this time, since the temperature of the heat storage material 103 is lower than the melting point (predetermined temperature) of the heat storage material 103, it is all solid and exists vertically below, and a region (gas zone) where gas exists is formed vertically above. Yes. At this time, since heat is transferred through the solid heat storage material 103 (heat conduction), the solid heat storage material 103 functions as a heat transfer portion. On the other hand, in the gas zone, heat is transferred by natural convection of the gas (heat transfer), but since the amount of heat transfer is small, the gas zone functions as a heat insulating portion where heat is not transferred. Accordingly, if the type and volume of the heat storage material 103 are determined so that the heat insulation by the gas zone is more dominant than the heat transfer through the solid heat storage material 103, the heat transfer member 101 as a whole has the heat transfer. The member 101 functions as a heat insulating member. While it is necessary to prevent heat from escaping from the engine to the outside of the engine while the engine is warming up, the heat transfer member 101 functions as a heat insulating member. It will be prevented from escaping.

  Next, (b) shown in the middle part of FIG. 4A shows a state where the engine is operated at a high load. When the engine is operated at a high load and high-temperature heat is generated, the engine cooling water rises to about 110 ° C., for example. The high-temperature heat at this time is stored in the polymer compound member 24. At this time, since the temperature of the heat storage material 103 rises beyond the melting point (predetermined temperature) in response to the heat stored in the polymer compound member 24, all of the heat storage material 103 changes from solid to liquid. At this time, the heat storage material 103 takes heat from the surroundings as melting heat. Further, heat generated by the engine is released from the polymer compound member 24 to the outside air through the heat storage material 103 that has become liquid (heat radiation). In this case, the heat of dissolution when the phase changes from solid to liquid is smaller than the heat of vaporization when the phase changes from liquid to gas, and the movement of the liquid is not as easy as gas. Therefore, if the liquid does not move from the inside (position surrounded by the polymer compound member 24) to the outside (position contacting the outside air), the amount of heat transferred from the polymer compound member 24 to the outside air is limited. Become. However, conveniently, the engine has an excitation source due to explosion pressure or inertial force, and therefore vibrates periodically as the crankshaft rotates. That is, the heat storage material 103 that has become liquid due to the vibration of the engine is vibrated. Due to this vibration, the heat storage material 103 that has become liquid is transferred from the inside (position surrounded by the polymer compound member 24) to the outside (position contacting the outside air) (to the left in FIG. 4A) or from the outside to the inside (FIG. It moves easily in the right direction in 4A. The movement of the liquid heat storage material 103 from the inside to the outside carries the heat of the polymer compound member 24 to the outside air, and the liquid heat storage material 103 that has released the heat is then returned from the outside to the inside. . This is heat transfer because heat is transferred by the flow of the liquid heat storage material 103. In heat transfer, heat moves in proportion to the temperature difference between the temperature of the polymer compound member 24 and the temperature of the outside air. Therefore, if the amount of movement of the liquid heat storage material 103 increases, the amount of heat transfer increases accordingly. Become. Since heat transfer is actively performed by the convection (movement) of the liquid heat storage material 103, the heat transfer member 101 functions as a heat dissipation member, and heat dissipation from the polymer compound member 24 to the outside air is promoted. .

  (C) shown in the lower part of FIG. 4A shows that the vehicle on which the engine is mounted is in a stopped state. It is assumed that when idling stop is performed to stop the engine temporarily while the vehicle is stopped, the temperature of the engine decreases and the cooling water of the engine decreases to, for example, about 90 ° C. Accordingly, the temperature of the polymer compound member 24 decreases, so that the temperature of the heat storage material 103 also decreases, and the heat storage material 103 again undergoes a phase change from a liquid to a solid, and a gas exists vertically above. (Gas zone) is formed. That is, the heat transfer member 101 is in the same state as (a) shown in the upper part of FIG. 4A. While it is necessary to prevent heat from escaping from the polymer compound member 24 to the outside of the engine while the vehicle is stopped, the heat transfer member 101 functions as a heat insulating member. As a result, the heat stored in the polymer compound member 24 is prevented from being released from the polymer compound member 24 to the outside air, and the engine is kept warm.

  Although the heat storage material of the heat transfer member 101 provided in the upper oil pan structure 41 is not shown, it works in the same manner as FIG. 4A.

  Thus, in consideration of the decrease in heat dissipation of the engine due to the replacement of the polymer compound member for weight reduction, heat exchange is performed by arranging the heat transfer member 101 having a function capable of switching between heat dissipation and heat insulation. Possible structures 22 and 41 are constructed. By using the heat exchangeable structures 22 and 41, heat dissipation is improved particularly in a high load state of the engine. As a result, there is no inconvenience in the cooling performance and lubrication performance of the engine from the cold start of the engine to the high load state even if the weight is reduced, so that the conventional water pump and oil pump can be used as they are. .

  Now, since the heat storage material 103 changes to a solid in a temperature range below its melting point and changes to a liquid in a temperature range higher than its melting point, it changes according to each operation state of the engine shown in FIG. 4A. It is necessary to determine the melting point (predetermined temperature) of the heat storage material 103 so that the phase changes optimally.

  First, consider how to set the lower limit of the melting point. The opening temperature of the thermostat valve 6 is 60 ° C to 80 ° C. That is, the thermostat 6 starts to open when the cooling water flowing through the cooling water passage is around 60 ° C., and becomes fully open when it reaches 80 ° C. With the valve opening temperature of the thermostat valve 6 as a predetermined switching temperature, the lower limit of the melting point of the heat storage material 103 is preferably equal to or lower than the valve opening temperature, preferably 60 ° C. which is the lowest value of the valve opening temperatures. Set to.

  The reason is as follows. That is, in the temperature range of 60 ° C. or less, which is the lowest value of the opening temperature of the thermostat valve 6, the radiator 3 is bypassed to cool the coolant in order to warm up the engine immediately after starting the engine in the cold state. Is flowing. In this case, when the melting point of the heat storage material 103 is set to be lower than 60 ° C., which is the lowest value among the valve opening temperatures, the heat storage material 103 becomes liquid even in the temperature range where the thermostat valve 6 is fully closed. And phase change. The liquid heat storage material 103 receives the vibration of the engine as described above and convects between the inside and the outside to release heat to the outside air. In the temperature range where the thermostat valve 6 is in the fully closed state, the engine must be warmed up early, but heat transfer is actively performed by the convection of the liquid heat storage material 103 and the polymer compound member 24 is stored. Heat will be actively released to the outside, prolonging the time to complete engine warm-up. Therefore, the lower limit of the melting point of the heat storage material 103 is the valve opening temperature of the thermostat 6 so that the heat storage material 103 becomes liquid and heat is not released from the polymer compound members 24 and 43 to the outside air while the engine is warmed up. The minimum value is set to 60 ° C. or higher.

  Next, consider how to set the upper limit of the melting point. If the engine becomes hot and the cooling water flowing through the cooling water passage evaporates, the engine will overheat. Therefore, the boiling point of the cooling water flowing through the cooling water passage should be controlled to 110 ° C to 130 ° C. Yes. Here, 110 ° C. is a limit of an allowable value at which the cooling water cannot be deteriorated, and if it exceeds 110 ° C., the cooling water may be deteriorated. Considering this cooling water deterioration, the upper limit of the melting point of the heat storage material 103 is set to be equal to or lower than the boiling point of the cooling water, and preferably set to 110 ° C. which is the lowest value of the boiling points of the cooling water. .

  The reason is as follows. That is, if the melting point of the heat storage material 103 is set to a temperature exceeding 110 ° C. which is the lowest value of the boiling points of the cooling water flowing through the cooling water passage, the heat storage material 103 is stored even in a temperature range where the cooling water can be deteriorated. Since the material 103 remains in a solid state, the heat transfer member 101 functions as a heat insulating member. In the temperature range where the cooling water can be deteriorated, the engine must be cooled rapidly, but the heat storage material 103 stays in a solid state and the heat transfer member 101 functions as a heat insulating member. This will cause the cooling water to deteriorate. Therefore, in the temperature range where the cooling water can be deteriorated, the upper limit of the melting point of the heat storage material 103 is the cooling water so that the heat storage material 103 becomes liquid and heat is actively released from the polymer compound members 24 and 43 to the outside air. It is set so as to be 110 ° C. or lower which is the lowest value of the boiling points.

  Paraffin wax is used as the heat storage material 103, but the heat storage material 103 is not limited thereto, and any organic heat storage material may be used. Another example of paraffin wax is a commercially available wax. Since these waxes are a mixture of many kinds of substances, the melting point can be adjusted by the substances to be mixed. Therefore, a commercially available wax satisfying the lower limit and upper limit conditions of the melting point may be selected, or a wax satisfying the lower limit and upper limit conditions of the melting point may be newly produced by mixing different substances. In addition, naphthalene, myristic acid, stearic acid, polyethylene glycol, or the like can be used as the heat storage material 103.

  In the embodiment, the plurality of heat transfer members 101 are arranged in the cylinder block structure 22 and the upper oil pan structure 41, respectively, but it is not always necessary to arrange the plurality of heat transfer members 101. At least one cylinder block structure 22 and one upper oil pan structure 41 may be disposed. That is, the number and shape of the heat transfer members 101 and the positions at which the heat transfer members 101 are arranged in the cylinder block structure 22 and the upper oil pan structure 41 are the same as the hollow metal members of the structures 22 and 41. As long as it arrange | positions so that a high molecular compound member may be connected, it is arbitrary. This will be described. FIG. 5 is an enlarged cross-sectional view of part A in FIG. 3, and FIG. 6 is an enlarged cross-sectional view of part B in FIG. 5 and 6 show the four aspects of the first embodiment side by side in the vertical direction. 5 and 6 also do not show the internal state of the heat transfer member 101.

  As shown in the uppermost part of FIG. 5, in the case of FIG. 3, one end (the right end in FIG. 5) of the heat transfer member 101 protrudes (exposes) from the outer surface 22 a of the cylinder block structure 22. The present invention is not limited to this case, as long as the outer peripheral member 23a of the hollow metal member 23 and the polymer compound member 24 are connected as shown in the second stage of FIG. 5 as another aspect of the first embodiment. The one end of the heat transfer member 101 may not protrude from the outer surface 22a of the cylinder block structure 22. Further, as shown in the third and fourth stages of FIG. 5 as another aspect of the first embodiment, the other end (the left end in FIG. 5) of the heat transfer member 101 is the inner peripheral member of the hollow metal member 23. You may connect with 23b.

  As shown in the uppermost part of FIG. 6, in the case of FIG. 3, one end (right end in FIG. 6) of the heat transfer member 101 protrudes (exposes) from the outer surface 41 a of the upper oil pan structure 41. The present invention is not limited to this case, as long as the outer peripheral member 42a of the hollow metal member 42 and the polymer compound member 43 are connected as shown in the second stage of FIG. 6 as another aspect of the first embodiment. The one end of the heat transfer member 101 may not protrude from the outer surface 41a of the upper oil pan structure 41. Further, as shown in the third and fourth stages of FIG. 6 as another aspect of the first embodiment, the other end (left end in FIG. 6) of the heat transfer member 101 is the inner peripheral member of the hollow metal member 42. You may connect with 42b.

  5 and 6, the heat transfer member 101 has a rectangular cross section, but may have an elliptical cross section. The overall shape of the heat transfer member 101 may be a pencil shape with a hexagonal cross section, a capsule shape with both ends protruding with curved surfaces (see FIG. 4A), or a flat plate shape as shown in FIG. Here, in FIG. 2, it is assumed that the cylinder block structure 22 and the upper oil pan structure 41 are provided over the entire two side surfaces of the cylinder block 11 and the upper oil pan 31 in the longitudinal direction of the engine. In this case, as shown in FIG. 2, the heat transfer member 101 disposed on the cylinder block structure 22 provided on the side surface in the engine longitudinal direction may be a flat plate that runs horizontally in the engine longitudinal direction. In FIG. 2, only the portion protruding (exposed) from the surface of the cylinder block structure 22 is shown, so that the three horizontal chopstick-shaped heat transfer members 101 from the top and the fourth horizontal chopstick-shaped from the bottom. This heat transfer member 101 is the flat heat transfer member 101 referred to herein. The horizontal split chopstick-shaped heat transfer member 101 has a rectangular cross section, but may have an elliptical shape. In FIG. 2, the plurality of rod-shaped heat transfer members 101 arranged in the cylinder block structure 22 are shown fourth from the top and third from the bottom.

  Similarly, the heat transfer member 101 disposed in the upper oil pan structure 41 provided on the side surface in the longitudinal direction of the engine also has a capsule shape in which the cross section is a hexagonal pencil shape and both ends protrude with curved surfaces ( In addition to the configuration shown in FIG. 4A, it may be a flat plate running in the longitudinal direction of the engine as shown in FIG. In FIG. 2, only the portion protruding (exposed) from the surface of the upper oil pan structure 41 is shown, so the second horizontal chopstick-shaped heat transfer member 101 from the bottom is the flat plate-like shape here. It is the heat transfer member 101. The horizontal split chopstick-shaped heat transfer member 101 has a rectangular cross section, but may have an elliptical shape. In FIG. 2, the plurality of rod-like heat transfer members 101 arranged in the upper oil pan structure 41 are shown first from the bottom.

  As described above, the overall shape of the heat transfer member 101 includes a hexagonal pencil shape in cross section, a capsule shape in which both ends protrude with curved surfaces, a plate shape, and a rod shape, but the shape of the heat transfer member 101 is a case. I just need it. The case generally refers to a box shape, but is not limited to a box shape, but is used in a broad concept including all of the pencil shape, capsule shape, plate shape, and rod shape. Any shape may be used as long as the heat storage material can be enclosed therein.

  2 and FIG. 3 do not correspond to the number and position of the heat transfer members 101. That is, FIG. 2 shows the heat transfer members 101 arranged in the cylinder block structure 22 and the upper oil pan structure 41 regardless of the number and arrangement of the heat transfer members 101 shown in FIG.

  Next, the lower oil pan 51 of the present embodiment is made of only a polymer compound member, so that it is lighter than when the lower oil pan is formed of a uniform metal member. On the other hand, however, if the lower oil pan 51 is formed only of a polymer compound member, heat is released to the outside air at a high engine load because the heat insulation is better than when the lower oil pan is formed of a uniform metal member. It becomes difficult. Therefore, in the present embodiment, one end of the second heat transfer member 105 similar to the heat transfer member 101 is projected (exposed) to the lower oil pan 51 formed only of the polymer compound member. Deploy. Here, the heat transfer characteristics of the second heat transfer member 105 are also increased as the temperature of the second heat transfer member 105 increases due to the temperature of the second heat transfer member 105 itself, as with the heat transfer member 101. It changes to make it easier to convey. Specifically, the second heat transfer member 105 disposed in the lower oil pan 51 is configured by enclosing a heat storage material 107 (medium) such as paraffin wax in a hollow metal member 106 as shown in FIG. 4B. Yes. For this reason, the ease of movement of the heat storage material 107 in the hollow metal member 106 changes depending on the temperature of the second heat transfer member 105 itself, whereby the heat transfer characteristics of the second heat transfer member 105 change.

  Specifically, the heat storage material 107 is solid when it is equal to or lower than a predetermined temperature that is the melting point of the heat storage material 107, and changes in phase when it exceeds a predetermined temperature. That is, when the heat storage material 107 is in a solid state, it is difficult to move within the hollow metal member 106 (the amount of movement of the heat storage material 107 is relatively reduced). When the amount of movement of the heat storage material 107 decreases, the amount of heat transfer also decreases. On the other hand, when the heat storage material 107 is in a liquid state, the heat storage material 107 is easily moved in the hollow metal member 106 (the amount of movement of the heat storage material 107 is relatively increased). The amount of heat transfer increases as the amount of movement of the heat storage material 107 increases.

  Here, the mechanism of switching between heat dissipation and heat insulation by the second heat transfer member 105 will be described with reference to FIG. 4B.

  FIG. 4B is similar to FIG. 4A in three different states (a state where the engine is warmed up, a state where the engine is operating at a high load, and a state where the engine is mounted is stopped). It shows how the heat storage material 107 housed in the second heat transfer member 105 changes its state. Also in FIG. 4B, the vertical direction is the vertical direction, and the entire shape of the second heat transfer member 105 is a capsule shape that is long in the horizontal direction, and the second heat transfer member is placed on the lower oil pan 51 formed of a polymer compound. 105 is arranged. Furthermore, it is assumed that one end (the left end in FIG. 4B) of the second heat transfer member 105 protrudes from the outer surface 51 a of the lower oil pan 51 to the outside air.

  First, as shown in (a) of FIG. 4B, the engine cooling water in the middle of warming up is about 60 ° C., for example. At this time, since the temperature of the heat storage material 107 is lower than the melting point of the heat storage material 107, all of the heat storage material 107 is solid and exists vertically downward, and a region (gas zone) where gas exists is formed vertically upward. At this time, since heat is transferred through the solid heat storage material 107 (heat conduction), the solid heat storage material 103 functions as a heat transfer portion. On the other hand, in the gas zone, heat is transferred by natural convection of the gas (heat transfer), but since the amount of heat transfer is small, the gas zone functions as a heat insulating portion where heat is not transferred. Therefore, if the type and volume of the heat storage material 107 are determined so that the heat insulation by the gas zone is more dominant than the heat transfer through the solid heat storage material 107, the heat transfer member 105 as a whole can be used as a heat transfer member 105. The member 105 functions as a heat insulating member. Since it is necessary to prevent heat from escaping from the polymer compound member (51) to the outside during the engine warm-up, the heat transfer member 105 functions as a heat insulating member. It will be prevented from escaping from the member (51) to the outside air.

  Next, as shown in the middle part (b) of FIG. 4B, when the engine is operated at a high load and high-temperature heat is generated, the engine cooling water rises to about 110 ° C., for example. The high-temperature heat at this time is stored in the polymer compound member forming the lower oil pan 51. At this time, since the temperature of the heat storage material 107 rises beyond the melting point in response to heat stored in the polymer compound member, all of the heat storage material 107 undergoes a phase change from solid to liquid. At this time, the heat storage material 107 takes heat from the surroundings as melting heat. Furthermore, heat is released from the polymer compound member (51) to the outside air (heat radiation) through the heat storage material 107 that has become liquid. In this case, the heat of dissolution when the phase changes from solid to liquid is smaller than the heat of vaporization when the phase changes from liquid to gas, and the movement of the liquid is not as easy as gas. Therefore, if the liquid does not move from the inside (position surrounded by the polymer compound member) to the outside (position contacting the outside air), the amount of heat transferred from the polymer compound member (51) to the outside air is limited. It becomes. However, conveniently the engine vibrates. That is, the heat storage material 107 that has become liquid due to the vibration of the engine is vibrated. Due to this vibration, the heat storage material 107 that has become a liquid moves from the inside (position surrounded by the polymer compound member) to the outside (position in contact with the outside air) (to the left in FIG. 4B) or from the outside to the inside (FIG. 4B). In the right direction) and move easily. The heat of the polymer compound member (51) is transferred to the outside air by the movement of the heat storage material 107 that has become liquid from the inside to the outside, and the liquid heat storage material 107 that has released the heat is now returned from the outside to the inside. It is. This is heat transfer because heat is transferred by the flow of the liquid heat storage material 107. In heat transfer, heat moves in proportion to the temperature difference between the temperature of the polymer compound member and the temperature of the outside air. Therefore, if the amount of movement of the liquid heat storage material 107 increases, the amount of heat transfer increases accordingly. . Since heat transfer is actively performed by the convection (movement) of the liquid heat storage material 107, the heat transfer member 105 functions as a heat dissipation member, and heat dissipation from the polymer compound member (51) to the outside air is promoted. It becomes.

  As shown in (c) in the lower part of FIG. 4B, when the engine is temporarily stopped while the vehicle is stopped, the temperature of the engine decreases, and the cooling water of the engine decreases to, for example, about 90 ° C. Suppose that In accordance with this, the temperature of the polymer compound member forming the lower oil pan 51 decreases, so the temperature of the heat storage material 107 also decreases, and the heat storage material 107 again undergoes a phase change from liquid to solid, A region (gas zone) where gas exists vertically above is formed. That is, the heat transfer member 105 is in the same state as (a) shown in the upper part of FIG. 4B. While stopping, it is necessary to prevent heat from escaping from the polymer compound member (51) to the outside of the engine. However, since the heat transfer member 105 functions as a heat insulating member, the polymer compound member (51) is stored. The heat that is in the air is prevented from being released to the outside air, and the engine is kept warm.

  The lower limit and upper limit of the melting point of the heat storage material 107 housed inside the second heat transfer member 105 may be the same as the lower limit and upper limit of the melting point of the heat storage material 103 sealed inside the heat transfer member 101.

  Since the lower oil pan 51 is formed of a polymer compound member, it originally has a heat insulating effect. Therefore, disposing the second heat transfer member 105 in the lower oil pan 51 means that the heat exchangeable lower oil pan 51 having a heat radiation function is configured. That is, when the engine is heavily loaded, high-temperature heat generated by the engine is released from the polymer compound member (51) to the outside air via the second heat transfer member 105. Thereby, at the time of high load, the rise of the cooling water temperature and the oil temperature can be suppressed as compared with the case where the second heat transfer member 105 is not disposed in the lower oil pan 51.

  Here, the function and effect of the first embodiment will be described.

  In the first embodiment, the aluminum die cast part of the cylinder block 11 and a part of the aluminum alloy part of the upper oil pan 31 (at least part of the engine structure) are made of the hollow metal members 23 and 42 (metal member) and the polymer compound. The heat transfer member 101 is configured to include the members 24 and 43 and arranged so as to connect the hollow metal members 23 and 42 and the polymer compound members 24 and 43. According to the first embodiment, by replacing the aluminum die cast part of the cylinder block 11 and the aluminum alloy part of the upper oil pan 31 with the polymer compound members 24 and 43, an aluminum die cast uniform member like a conventional cylinder block is obtained. Compared with the structure of the aluminum alloy uniform member such as the conventional upper oil pan, the cylinder block 11 is made by the amount corresponding to the specific gravity difference between the aluminum die cast member and the polymer compound 24 and the volume of the polymer compound member. The upper oil pan 31 can be reduced in weight by the specific gravity difference between the aluminum alloy member and the polymer compound member 43 and the volume of the polymer compound member 43. In addition, the cylinder block structure 22 and the upper oil pan structure 41 capable of heat exchange are configured by disposing the heat transfer member 101, so that the cooling water temperature and the oil temperature do not become excessively high particularly when the engine is under a high load. The cooling water temperature and the oil temperature can be kept at the same level as the conventional one, thereby avoiding seizure of the bearing portion inside the engine.

  According to the first embodiment, since the heat transfer characteristics of the heat transfer member 101 change depending on the temperature of the heat transfer member 101 itself, the amount of heat transferred changes depending on the temperature of the heat transfer member 101 itself. The heat radiation from the engine and the heat insulation that blocks the heat radiation from the engine can be switched according to the temperature state of the engine according to the temperature of 101 itself.

  According to the first embodiment, the heat transfer characteristics of the heat transfer member 101 change so that heat becomes easier to transfer as the temperature of the heat transfer member 101 itself becomes higher. When the engine is relatively cold, heat dissipation from the engine can be cut off.

  According to the first embodiment, the heat transfer member 101 includes a hollow metal member 102 (housing) and a heat storage material 103 (medium) sealed inside the hollow metal member 102, and the heat transfer member 101 itself. The ease of movement of the heat storage material 103 in the hollow metal member 102 changes depending on the temperature, so that the heat transfer characteristics of the heat transfer member 101 change. Therefore, the heat storage material 103 moves when the engine is relatively hot. It becomes easy to dissipate heat from the engine, and when the engine is at a relatively low temperature, the heat storage material 103 is difficult to move, and heat dissipation from the engine can be blocked.

  According to the first embodiment, the heat storage material 103 (medium) is solid when it is equal to or lower than the melting point (predetermined temperature) of the heat storage material 103 and becomes liquid when the melting point of the heat storage material 103 is exceeded. Is relatively low, the heat storage material 103 becomes a solid and accumulates vertically downward, and a gas zone is formed vertically upward. Therefore, the heat transfer member 101 functions as a heat insulating member as a whole. That is, when the cooling water temperature and the oil temperature are relatively low, engine warm-up can be promoted by the function of the heat transfer member 101 as a heat insulating member. On the other hand, when the cooling water temperature or the oil temperature is relatively high as in a high load, the heat storage material 103 becomes liquid, and the movement amount of the heat storage material 103 in the hollow metal member 102 is relatively affected by the vibration of the engine. Therefore, the heat transfer member 101 now functions as a heat dissipation member. That is, when the coolant temperature and the oil temperature are relatively high, the engine can be cooled by actively releasing heat from the engine. Further, when the cooling water temperature or the oil temperature is gradually lowered due to idling stop by stopping, the heat storage member 103 in the hollow metal member 102 is phase-converted into a solid and a gas zone is generated upward, so that the heat transfer member 101 is entirely As a heat insulating member. That is, when the cooling water temperature or the oil temperature is gradually lowered due to the idling stop due to the stop, the heat transfer member 101 acts as a heat insulating member to suppress a rapid drop in the oil water temperature (exhibiting the oil temperature warming effect). ). This heat retention effect improves fuel efficiency at cold start after prolonged idle stop.

  According to the first embodiment, the cooling device 2 that circulates the cooling water to cool the engine is provided, and the cooling device 2 has a temperature of the cooling water of 60 ° C. that is the lowest value among the opening temperatures of the thermostat valve 6. The cooling water passage is switched so that the amount of heat dissipated from the cooling water to the outside of the engine is increased above (predetermined switching temperature), and the melting point (predetermined temperature) of the heat storage material 103 is set to open the thermostat valve 6. Since it is 60 ° C. (predetermined switching temperature) which is the lowest value among the temperatures, when the cooling water temperature or the oil temperature is relatively low, the heat storage material 103 is phase-converted into a solid so that the gas zone is located above. As a result, the heat transfer member 101 functions as a heat insulating member as a whole. As a result, warming up of the engine can be promoted, and it is possible to avoid prolonging the time until completion of warming up of the engine.

  According to 1st Embodiment, since the melting | fusing point (predetermined temperature) of the thermal storage material 103 is below the boiling point of cooling water, when the cooling water temperature or oil temperature is relatively high, the thermal storage material 103 phase-converts into a liquid. Thus, the heat transfer member 101 functions as a heat dissipation member and actively dissipates heat. As a result, it is possible to avoid the cooling water temperature from reaching a temperature range where the cooling water can be deteriorated when the engine is under a high load.

  According to the first embodiment, the engine structure includes a cylinder block structure 22 and an upper oil pan structure 41 (which includes hollow metal members 23 and 42 (metal members) and polymer compound members 24 and 43). 1) and a lower oil pan 51 (second structure) composed only of a polymer compound member, and the heat transfer member 101 is connected to the cylinder block structure 22 and the upper oil pan structure 41. Therefore, a part of the conventional cylinder block 11 and the upper oil pan 31 formed of the metal uniform member is replaced with the polymer compounds 24 and 43, and the specific gravity of both and the polymer compound member 24, The cylinder block 11 and the upper oil pan 31 can be reduced in weight by an amount corresponding to the volume of 43. In addition, since the heat transfer member 101 is disposed in the cylinder block structure 22 and the upper oil pan structure 41, the cooling water temperature and the oil temperature do not become excessively high when the engine is relatively hot, and the bearing inside the engine You can avoid seizure.

  According to the first embodiment, since the second heat transfer member 105 is disposed in the lower oil pan 51 (second structure) composed only of the polymer compound member, the lower oil pan 51 capable of heat exchange. Therefore, even when the lower oil pan 51 composed only of the polymer compound member is provided, the cooling water temperature and the oil temperature do not become too high when the engine is relatively hot, In addition, the warm-up promotion during cold start and the heat retention effect after engine stop are improved.

  According to the first embodiment, the engine structure includes a cylinder head 61, a cylinder block 11, an upper oil pan 31, and a lower oil pan 51. The first structure includes the cylinder block 11 and the upper oil pan 31 ( At least one of a cylinder head, a cylinder block, and an upper oil pan), and the second structure is a lower oil pan 51. Among the engine structures, the cylinder block 11 and the upper oil pan 31 are originally heavy members, and a part of these members is replaced with a first structure composed of a metal member and a polymer compound member. The engine can be significantly reduced in weight. And since the 2nd structure comprised only with a high molecular compound member is the lower oil pan 51, the heat retention effect improves.

  According to the first embodiment, part of the heat transfer member 101 protrudes (exposes) outside the engine from the outer surfaces of the cylinder block structure 22 and the upper oil pan structure 41 (engine 1 structure). The heat dissipation performance from the engine can be improved.

(Second Embodiment)
FIG. 7 is a longitudinal sectional view of the engine 1 cut along a plane perpendicular to the engine longitudinal direction of the second embodiment, which replaces FIG. 3 of the first embodiment. The same parts as those in FIG. 3 are denoted by the same reference numerals.

  In the first embodiment, a part of the aluminum die cast part of the cylinder block 11 is replaced with the structure 22, and a part of the aluminum alloy part of the upper oil pan 31 is replaced with the structure 41. The heat transfer member 101 is connected so that the hollow metal member 23 and the polymer compound member 24 are connected to the structure 22, and the heat transfer is performed so that the hollow metal member 42 and the polymer compound member 43 are connected to the structure 41. Each member 101 was disposed. On the other hand, in the second embodiment, only a part of the aluminum alloy part of the upper oil pan 31 is replaced with the upper oil pan structure 41 as in the first embodiment, and the structure 41 is replaced with a hollow metal member 42 and a polymer. The heat transfer member 101 is disposed so as to connect the compound member 43. In other words, in the second embodiment, the cylinder block 11 constituted by the aluminum die-cast uniform member remains the same as before.

  Also in the second embodiment, the upper oil pan structure 41 and the heat transfer member 101 have the same operational effects as in the first embodiment.

(Third embodiment)
FIG. 8 is a longitudinal sectional view of the engine 1 cut along a plane orthogonal to the engine longitudinal direction of the third embodiment, which replaces FIG. 3 of the first embodiment. The same parts as those in FIG. 3 are denoted by the same reference numerals.

  In the first embodiment, the lower oil pan 51 is formed of only a polymer compound member for weight reduction. However, there are still few engines in which the lower oil pan 51 is formed of only a polymer compound member, and an engine in which the lower oil pan 51 is formed of a uniform metal member such as iron, aluminum, or magnesium is more common. . The third embodiment is based on the lower oil pan 51 formed of such a metal uniform member, and a part of the metal portion of the lower oil pan 51 is replaced with the lower oil pan structure 111. Here, the range of the lower oil pan structure 111 is surrounded by a short broken line. In addition, since the structure of the cylinder block 11 and the upper oil pan 31 is the same as the structure of 1st Embodiment, the description is abbreviate | omitted.

  The configuration of the lower oil pan structure 111 is slightly different from that of the cylinder block structure 22 and the upper oil pan structure 41. That is, the lower oil pan structure 111 is configured by stacking and bonding a polymer compound member 113 having the same shape as the lower oil pan member 112 on the outer periphery of the lower oil pan member 112 made of sheet metal on the vertically lower side. . Here, the joining of the lower oil pan member 112, which is a metal member, and the polymer compound member 113 is not limited to the method using an adhesive. A joining method that does not use an adhesive that has recently appeared (joining a metal member and a polymer compound member by an anchor effect) may be used.

  Thus, as a whole of the lower oil pan 51, a part of the metal portion of the conventional lower oil pan formed of the metal uniform member is replaced with the polymer compound member 113. If the polymer compound member 113 and the metal member are compared, the specific gravity is smaller in the polymer compound member 113, so the lower oil pan 51 is lightened by the amount obtained by multiplying the difference in specific gravity between the two by the volume of the polymer compound member 113. Will be. As described above, the third embodiment has room for application when the lower oil pan 51 is formed of a uniform metal member and the lower oil pan 51 is thick enough to be replaced with the lower oil pan structure 111. .

  On the other hand, replacing a part of the metal portion of the lower oil pan 51 with the lower oil pan structure 111 in which the polymer compound member 113 is laminated and bonded to the lower oil pan member 112, which is a metal member, is a heat transfer surface. May be disadvantageous. That is, when the engine 1 actively generates heat as in a high load, it is desirable to release a large amount of heat from the lower oil pan structure 111 to the outside air accordingly. At this time, if the polymer compound member 113 inside the lower oil pan structure 111 worked as a heat insulating member, the effect of cooling the engine particularly at a high load of the engine is lowered unlike the lower oil pan 51 of the metal uniform member. To do.

  Therefore, the heat transfer member 114 is disposed so as to connect the lower oil pan member 112 made of sheet metal and the polymer compound member 113 to the lower oil pan structure 111. One end of the heat transfer member 114 is projected (exposed) from the outer surface of the structure 111 to the outside of the engine. This is to improve the heat dissipation performance from the engine via the heat transfer member 114 especially when the engine is heavily loaded. Note that FIG. 8 does not show the internal state of the heat transfer member 114.

  The configuration of the heat transfer member 114 is the same as that of the heat transfer member 101 of the first embodiment. That is, the heat transfer characteristics of the heat transfer member 114 change so that the heat transfer becomes easier as the temperature of the heat transfer member 114 itself becomes higher due to the temperature of the heat transfer member 114 itself. Specifically, the heat transfer member 114 arranged in the structure 111 is configured by enclosing a heat storage material (medium) such as paraffin wax in a hollow metal member, as shown in FIG. 4A. For this reason, the heat transfer characteristic of the heat transfer member 114 is changed by changing the ease of movement of the heat storage material in the hollow metal member depending on the temperature of the heat transfer member 114 itself.

  Specifically, the heat storage material is solid when the temperature is equal to or lower than a predetermined temperature that is the melting point of the heat storage material, and when the heat storage material exceeds the predetermined temperature, the phase changes to a liquid. That is, when the heat storage material is in a solid state, it is difficult to move within the hollow metal member (the amount of movement of the heat storage material is relatively reduced). If the amount of movement of the heat storage material decreases, the amount of heat transfer also decreases. On the other hand, when the heat storage material is in a liquid state, the heat storage material is easily moved within the hollow metal member (the amount of movement of the heat storage material is relatively increased). The amount of heat transfer increases as the amount of movement of the heat storage material increases.

  The material of the hollow metal member of the heat transfer member 114 is preferably a material having better thermal conductivity than the metal member forming the lower oil pan member 112 made of sheet metal.

  Considering that the heat dissipation of the engine is reduced by replacing the polymer compound member for weight reduction, heat exchange is performed by arranging the heat transfer member 114 having a function capable of switching between heat dissipation and heat insulation. A possible lower oil pan structure 111 is constructed. By using the heat-exchangeable lower oil pan structure 111, the heat dissipation is improved particularly in a high-load state of the engine. As a result, the weight reduction of the lower oil pan 51 does not inconvenience the cooling performance and lubrication performance of the engine from the cold start of the engine to the high load state. It can be used as it is.

  In the third embodiment, a plurality of heat transfer members 114 are arranged in the lower oil pan structure 111, but it is not always necessary to arrange a plurality of heat transfer members 114. At least one lower oil pan structure 111 may be disposed. That is, the number and shape of the heat transfer members 114 and the positions at which the heat transfer members 114 are arranged in the lower oil pan structure 111 are such that the heat transfer member 114 connects the hollow metal member of the structure 111 and the polymer compound member. As long as it is arranged, it is optional. Describing this, FIG. 9 is an enlarged cross-sectional view of a portion C in FIG. FIG. 9 shows two aspects of the third embodiment side by side. Note that FIG. 9 also does not show the internal state of the heat transfer member 114.

  As shown in the upper part of FIG. 9, in the case of FIG. 8, one end (the right end in FIG. 9) of the heat transfer member 114 protrudes (exposes) from the outer surface 111 a of the lower oil pan structure 111. In this case, the heat transfer member 114 is not limited as long as the lower oil pan member 112 and the polymer compound member 113 are connected as shown in the lower part of FIG. 9 as another aspect of the third embodiment. One end may not protrude from the outer surface 111a of the lower oil pan structure 111.

  In FIG. 9, the heat transfer member 114 has a rectangular cross section, but may have an elliptical cross section. As for the overall shape of the heat transfer member 114, as in the heat transfer member 101 of the first embodiment, the cross section is a hexagonal pencil shape, both ends are curved capsule shapes, and the flat plate shape shown in FIG. It can be considered. Here, FIG. 10 is a schematic perspective view in which the lower oil pan 51 is modeled in a simple shallow dish shape. In FIG. 10, the lower oil pan 51 is provided with a lower oil pan structure 111 over the entire two side surfaces in the engine longitudinal direction. In this case, as shown in FIG. 10, the heat transfer member 114 disposed in the lower oil pan structure 111 provided on the side surface in the engine longitudinal direction may be a flat plate that runs horizontally in the engine longitudinal direction. In FIG. 10, only the portion protruding (exposed) from the surface of the lower oil pan structure 111 is shown, so that the upper horizontal chopstick-like heat transfer member 114 is a flat plate-like heat transfer member here. 114. The horizontal split chopstick-shaped heat transfer member 114 has a rectangular cross section, but may have an elliptical shape. In FIG. 10, a plurality of rod-like heat transfer members 114 arranged in the lower oil pan structure 111 are further shown below.

  In FIGS. 8 and 10, the heat transfer member 114 is not arranged in a horizontal portion located vertically below the lower oil pan structure 111. This is because the minimum ground clearance of the vehicle is determined by the height position of the lower oil pan 51. Therefore, by arranging the heat transfer member 114 in the horizontal portion located vertically below the lower oil pan structure 111, the lowest This is to prevent the ground clearance from being lost. Of course, technically, the heat transfer member 114 can also be arranged in a horizontal portion located vertically below the lower oil pan structure 111, and in this case, care must be taken so that the minimum ground clearance does not change.

  In the third embodiment, a part of the metal part of the lower oil pan 51 (at least part of the engine structure) is composed of a lower oil pan member 112 (metal member) made of sheet metal and a polymer compound member 113, A heat transfer member 114 is provided so as to connect the lower oil pan member 112 made of sheet metal and the polymer compound member 113. According to the third embodiment, by replacing a part of the metal portion of the lower oil pan 51 with the polymer compound member 113, the metal member and the polymer compound member 113 are compared with the lower oil pan of the metal uniform member. The lower oil pan 51 can be reduced in weight according to the specific gravity difference between the two and the volume of the polymer compound member 113. In addition, since the lower heat pan structure 111 capable of heat exchange is configured by arranging the heat transfer member 114, the cooling water temperature and the oil temperature are not excessively high particularly when the engine is under a high load, and the cooling water temperature and the oil temperature are conventionally increased. It is possible to reduce the seizure of the bearing portion inside the engine.

(Fourth and fifth embodiments)
FIGS. 11 and 12 are longitudinal sectional views of the engine 1 cut along a plane orthogonal to the engine longitudinal direction of the fourth and fifth embodiments, which replace FIG. 8 of the third embodiment. The same parts as those in FIG. 8 are denoted by the same reference numerals.

  In the third embodiment shown in FIG. 8, on the assumption that the lower oil pan 51 is formed with a uniform metal member, a part of the metal member of the lower oil pan 51 is replaced with the lower oil pan structure 111. Further, the heat transfer member 114 is disposed so as to connect the lower oil pan member 112 made of sheet metal and the polymer compound member 113 to the lower oil pan structure 111. On the other hand, in the fourth and fifth embodiments shown in FIGS. 11 and 12, similarly to the third embodiment, the metal member of the lower oil pan 51 is premised on the assumption that the lower oil pan 51 is formed of a uniform metal member. Is replaced with the lower oil pan structure 111. Further, in the fourth and fifth embodiments, the heat transfer member 114 is arranged so as to connect the lower oil pan member 112 made of sheet metal and the polymer compound member 113 to the lower oil pan structure 111. This is the same as in the third embodiment.

  The fourth embodiment is different from the third embodiment in that a part of the aluminum die cast part of the cylinder block 11 is not replaced with the cylinder block structure 22 as in the third embodiment. Similarly, the fifth embodiment differs from the third embodiment in that a part of the aluminum die cast part of the cylinder block 11 and a part of the aluminum alloy part of the upper oil pan 31 are cylinders as in the third embodiment. The block structure 22 and the upper oil pan structure 41 are not replaced.

  Even in the fourth and fifth embodiments, the lower oil pan structure 111 and the heat transfer member 114 have the same effects as the third embodiment.

(Sixth embodiment)
FIG. 13 is a longitudinal sectional view of the engine 1 cut along a plane orthogonal to the engine longitudinal direction of the sixth embodiment, which replaces FIG. 3 of the first embodiment. The same parts as those in FIG. 3 are denoted by the same reference numerals.

  In the first and second embodiments, part of the metal parts of the cylinder block 11 and the upper oil pan 31 is replaced with the cylinder blocks and upper oil pan structures 22 and 41, and heat is transferred to the structures 22 and 41. The member 101 was arranged. In the third to fifth embodiments, a part of the metal portion of the lower oil pan 51 is replaced with the lower oil pan structure 111, and the heat transfer member 114 is arranged in the structure 111. On the other hand, in the sixth embodiment, a part of the aluminum alloy part of the cylinder head 61 is replaced with a cylinder head structure 121 in which a polymer compound member is housed and the outside is covered with metal. The heat transfer member 123 is arranged. Here, the range of the cylinder head structure 121 is shown surrounded by a two-dot chain line.

  More specifically, the cylinder head side surface 61a on the intake port 63 side (left side in FIG. 13), between the one opening end 63a of the intake port 63 that opens to the cylinder head side surface 61a and the cylinder head bottom surface 61b. The structure body 121 is pasted. In addition, since the shape of the cylinder head 61 is complicated, for convenience of explanation, the cylinder head structure 121 will be described as affixed to the side surface 61a of the cylinder head 61. However, simply attaching the cylinder head 61 reduces the weight of the cylinder head 61. Can not do it. Actually, a portion of the aluminum alloy portion of the cylinder head 61 that can be replaced by the intake side and the cylinder head structure 121 is searched, and that portion is replaced by the cylinder head structure 121.

  Here, the cylinder head structure 121 includes a hollow metal member 122 and a polymer compound member 123. The hollow metal member 122 includes an outer peripheral member 122a, an inner peripheral member 122b, and a member (not shown) that connects them, and the whole is formed of, for example, an aluminum alloy member. Since the cylinder head 61 is also an aluminum alloy member, there is actually no boundary between the cylinder head 61 and the inner peripheral member 122b, and the cylinder head and the inner peripheral member 122b are integrated.

  A polymer compound member 123 is accommodated in the hollow metal member 122. As the polymer compound member 123, a foamed resin that is light and excellent in heat insulation is desirable, as in the first embodiment. The material is not limited to the foamed resin, and any polymer compound material that is lighter than the metal material may be used.

  Accordingly, as a whole of the cylinder head 61, a part of the metal portion formed of the aluminum alloy member is replaced with the polymer compound member 123. If the high molecular compound member 123 is compared with the aluminum alloy member, the specific gravity is smaller in the high molecular compound member 123. Therefore, the weight of the cylinder head 61 is reduced by multiplying the difference in specific gravity between the two by the volume of the high molecular compound member 123. Will be.

  The number and shape of the cylinder head structures 121 and the positions where the cylinder head structures 121 are provided on the intake port 63 side are arbitrary. For example, the cylinder head structure 121 may be provided only near the specific intake port 63 or may be provided near the intake port 63 of each cylinder. It is good also as an integral shape which connected the cylinder head structure provided for every intake port 63. FIG.

  On the other hand, replacing a part of the aluminum alloy portion of the cylinder head 61 with the hollow metal member 122 containing the polymer compound member 123 may be disadvantageous from the viewpoint of heat transfer. That is, when the engine actively generates heat and becomes high temperature, such as during a high load, it is desirable to release a large amount of heat from the cylinder head structure 121 to the outside air accordingly. At this time, if the polymer compound member 123 inside the cylinder head structure 121 functions as a heat insulating member, the effect of cooling the engine particularly when the engine is under a high load is reduced as compared with the case where the cylinder head structure 121 is not provided.

  Therefore, the heat transfer member 124 is disposed so as to connect the outer peripheral member 122 a of the hollow metal member 122 and the polymer compound member 123. Note that FIG. 13 does not show the internal state of the heat transfer member 124.

  Here, similarly to the heat transfer member 101 of the first embodiment, the heat transfer characteristics of the heat transfer member 124 are such that heat is more easily transferred as the temperature of the heat transfer member 124 increases due to the temperature of the heat transfer member 124 itself. It will change. Specifically, the heat transfer member 124 is configured by encapsulating a heat storage material (medium) such as paraffin wax in a hollow metal member as in FIG. 4A. For this reason, the heat transfer characteristic of the heat transfer member 124 is changed by changing the ease of movement of the heat storage material in the hollow metal member depending on the temperature of the heat transfer member 124 itself.

  Specifically, the heat storage material is solid when it is below a predetermined temperature, which is the melting point of the heat storage material, and becomes liquid when it exceeds a predetermined temperature. That is, when the heat storage material is in a solid state, it is difficult to move within the hollow metal member (the amount of movement of the heat storage material is relatively reduced). If the amount of movement of the heat storage material decreases, the amount of heat transfer also decreases. On the other hand, when the heat storage material is in a liquid state, the heat storage material is easily moved within the hollow metal member (the amount of movement of the heat storage material is relatively increased). The amount of heat transfer increases as the amount of movement of the heat storage material increases.

  The material of the hollow metal member of the heat transfer member 124 is preferably a material having better thermal conductivity than the aluminum alloy member constituting the main body of the cylinder head 61.

  The mechanism of switching between heat dissipation and heat insulation by the heat transfer member 124 is the same as the mechanism of switching between heat dissipation and heat insulation by the heat transfer member 101 of the first embodiment.

  In this way, considering that the heat dissipation of the engine is reduced by replacing the polymer compound member for weight reduction, heat exchange is performed by arranging the heat transfer member 124 having a function capable of switching between heat dissipation and heat insulation. A possible cylinder head structure 121 is constructed. By using the cylinder head structure 121 capable of heat exchange, heat dissipation is improved particularly in a high load state of the engine. As a result, the weight reduction of the cylinder head 61 does not cause any inconvenience in the cooling performance and lubrication performance of the engine from the cold start of the engine to the high load state. Therefore, the conventional water pump and oil pump can be used as they are. Can be used.

  Also in the sixth embodiment, the cylinder head structure 121 and the heat transfer member 124 have the same effects as the cylinder block structure 22, the upper oil pan structure 41, and the heat transfer member 101 of the first embodiment. That is, in the sixth embodiment, a part of the aluminum alloy part of the cylinder head 61 (at least a part of the engine structure) is constituted by the hollow metal member 122 (metal member) and the polymer compound member 123, and the hollow metal A heat transfer member 124 is provided so as to connect the member 122 and the polymer compound member 123. According to the sixth embodiment, by replacing a part of the aluminum alloy portion of the cylinder head 61 with the polymer compound member 123, the aluminum alloy member is compared with the structure of a uniform aluminum alloy member such as a conventional cylinder head. The weight of the cylinder head 61 can be reduced by an amount corresponding to the specific gravity difference between the polymer compound member 123 and the volume of the polymer compound member 123. In addition, since the cylinder head structure 121 capable of heat exchange is configured by arranging the heat transfer member 124, the cooling water temperature and the oil temperature do not become excessively high particularly when the engine is under a high load, and the cooling water temperature and the oil temperature are reduced. This makes it possible to keep the same level as before, thereby avoiding seizure of the bearing portion inside the engine.

  In the embodiment, the case where the heat transfer member is a heat transfer member in which a heat storage material that changes phase between a solid and a liquid is encapsulated has been described. It can be used as a member. Here, the heat pipe is obtained by enclosing a volatile liquid (medium) as a working liquid in a pipe made of a material having high thermal conductivity. In the heat pipe, one of the pipes is heated as a high temperature part, and the other of the pipes is cooled as a low temperature part, whereby a cycle of evaporation and condensation of the working fluid occurs and heat is transferred. When such a heat pipe is used as a heat transfer member, for example, when the engine is heavily loaded, the working fluid absorbs heat of vaporization from the surroundings and evaporates at the high temperature portion. This steam travels through the cavity in the pipe to the cold part. The vapor cooled in the low temperature part aggregates and returns to the liquid, and again moves to the high temperature part. Thus, by giving a temperature difference to both ends, a working fluid circulates in a heat pipe, and the heat transfer from a high temperature part to a low temperature part occurs (heat dissipation improves).

  In the embodiment, the engine structure includes a cylinder head 61, a cylinder block 11, an upper oil pan 31, and a lower oil pan 51. The first structure includes the cylinder head 61, the cylinder block 11, and the upper oil pan 31. At least one and the second structure was the lower oil pan 51. The structure of the engine is not limited to this, and may include a cylinder head, a cylinder block, and an oil pan. At this time, the first structure is at least one of a cylinder head and a cylinder block, and the second structure is an oil pan.

  In the embodiment, the case where the cylinders of the engine are arranged in series has been described. However, the present invention is not limited to this. The present invention is also applicable to V-type and horizontally opposed engines.

1 Engine 11 Cylinder block 22 Cylinder block structure (first structure)
23 Hollow metal member (metal member)
24 Polymer compound member 31 Upper oil pan 41 Upper oil pan structure (first structure)
42 Hollow metal member (metal member)
43 Polymer compound member 51 Lower oil pan (second structure)
61 Cylinder head 101 Heat transfer member 102 Hollow metal member (housing)
103 Heat storage material (medium)
105 Second heat transfer member 106 Hollow metal member (housing)
107 Heat storage material (medium)
121 Cylinder head structure (first structure)
122 Hollow metal member (metal member)
123 Polymer compound member 124 Heat transfer member

Claims (12)

At least a part of the structure is composed of a metal member that is in contact with outside air and a polymer compound member that is disposed inside the engine from the metal member, and is disposed so as to connect the metal member and the polymer compound member. An engine comprising a heat transfer member.   The engine according to claim 1, wherein the heat transfer member changes in heat transfer characteristics depending on a temperature of the heat transfer member itself.   The engine according to claim 2, wherein the heat transfer characteristics of the heat transfer member change so that heat becomes easier to transfer as the temperature of the heat transfer member itself increases.   The heat transfer member is composed of a housing and a medium enclosed in the housing, and the ease of movement of the medium in the housing changes depending on the temperature of the heat transfer member itself. The engine according to claim 2 or 3, wherein a heat transfer characteristic of the heat transfer member changes.   The engine according to claim 4, wherein the medium is solid when the temperature is equal to or lower than a predetermined temperature, and becomes liquid when the predetermined temperature is exceeded. Equipped with a cooling device that circulates cooling water to cool the engine,
The cooling device is configured to switch the cooling water passage so that the amount of heat dissipated from the cooling water to the outside of the engine is increased when the temperature of the cooling water is equal to or higher than a predetermined switching temperature,
The engine according to claim 5, wherein the predetermined temperature is equal to or higher than the predetermined switching temperature.   The engine according to claim 6, wherein the predetermined temperature is equal to or lower than a boiling point of the cooling water. The structure includes a first structure composed of a metal member and a polymer compound member, and a second structure composed only of the polymer compound member,
The engine according to any one of claims 1 to 7, wherein the heat transfer member is disposed in the first structure.   The engine according to claim 8, wherein a second heat transfer member is disposed in the second structure. The structure includes a cylinder head, a cylinder block, and an oil pan,
The first structure is at least one of the cylinder head and the cylinder block;
The engine according to claim 8 or 9, wherein the second structure is the oil pan. The structure includes a cylinder head, a cylinder block, an upper oil pan, and a lower oil pan,
The first structure is at least one of the cylinder head, the cylinder block, and the upper oil pan;
The engine according to claim 8 or 9, wherein the second structure is the lower oil pan.   The engine according to any one of claims 1 to 12, wherein a part of the heat transfer member is exposed to the outside of the engine from an outer surface of the structure.

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