JP4821255B2 - Latent heat storage device and engine - Google Patents

Description

  The present invention relates to a latent heat storage device incorporated in an engine.

An engine at the time of cold start is required to complete warm-up early in order to reduce friction, improve fuel efficiency, improve output, and improve exhaust composition. In particular, components having sliding portions such as cylinder bores, pistons, crankshafts, and the like are desired to complete early warm-up in order to realize efficient operation. When an in-cylinder explosion starts, a normal engine warms engine components such as cylinder blocks and cylinder heads, and engine oil that circulates in the oil passages formed in these engine components. Progresses.
Conventionally, in order to achieve early warm-up completion of such an engine, a rapid warm-up device for an internal combustion engine in which a latent heat storage material (heat storage material) is stored in a heat storage material storage chamber formed so as to surround a cylinder has been proposed. (Patent Document 1). Such a rapid warm-up device is configured to apply a voltage to a heat storage material in a supercooled state when the engine is cold started, thereby starting a phase change and generating latent heat. .

JP 11-182393 A

  As described above, the rapid warm-up device for an internal combustion engine described in Patent Document 1 can raise the temperature locally around the cylinder directly immediately after the cold start, and can efficiently raise the temperature of the engine. It is.

  By the way, a water jacket is provided in the engine, and cooling water is circulated to cool the engine. Even in an engine equipped with a quick warm-up device as disclosed in Patent Document 1, the engine is normally cooled with cooling water.

  However, if the cooling water circulates through the water jacket, the heat is taken away, so that the heat generated by the latent heat storage material nucleating may be taken away to the outside. This wastes latent heat and prevents efficient warm-up.

  Therefore, an object of the present invention is to provide a latent heat storage device that can warm up the engine earlier and complete warm-up when the engine is started in the cold state.

In order to solve this problem, the latent heat storage device of the present invention includes a latent heat storage material container in which a latent heat storage material is enclosed and accommodated in a water jacket formed in a cylinder block of an engine, and the inside of the water jacket And cooling water circulation control means for controlling the circulation of the cooling water . By setting it as such a structure, until the engine warm-up is completed, the circulation of the cooling water can be stopped, and the movement of heat by the cooling water can be avoided. As a result, efficient warm-up can be performed, and friction can be reduced and fuel consumption can be improved. As a latent heat storage material used for such a latent heat storage device, a conventionally known latent heat storage material, such as sodium acetate trihydrate, can be employed. Further, the latent heat storage device can be configured to include conventionally known nucleation means such as a nucleation electrode and a needle body that appears and disappears with respect to the latent heat storage material.

In such a latent heat storage device, the latent heat storage material container is disposed on the cylinder block outer wall side in the water jacket, and cooling water is circulated between a bore side wall of the cylinder block and the latent heat storage material container. can do. This is a configuration that takes into account that the part to be cooled in the engine after completion of warm-up is the bore side wall of the cylinder block. That is, it is the structure which can cool a bore | boa side wall efficiently by circulating a cooling water along a bore | boa side wall. However, such a configuration is disadvantageous from the viewpoint of efficiently transferring the heat of the latent heat storage material to the bore side wall. In other words, at the time of designing, if it is important to improve the warm-up effect by the latent heat storage material, a latent heat storage material container is arranged on the bore wall side, and if the cooling effect of the engine after warm-up is prioritized, the latent heat storage The material container can be appropriately changed so as to be disposed on the cylinder block outer wall side in the water jacket.

Moreover, in such a latent heat storage device, the latent heat storage material container can be arranged on the bottom side in the water jacket, and cooling water can be circulated on the upper side of the latent heat storage material container . This is a configuration that takes into account that the part to be cooled in the engine after completion of warm-up is on the upper side of the cylinder block close to the combustion chamber. That is, the cooling water circulates in the upper part of the water jacket formed in the cylinder block, so that the portion close to the combustion chamber can be efficiently cooled.

  An object of the present invention is to stop the circulation of the cooling water before the completion of the warm-up to achieve an early warm-up, and to cool the engine by circulating the cooling water after the completion of the warm-up. Therefore, the cooling water circulation control means is configured by combining, for example, an electric water pump, a temperature measuring means, and an ECU for controlling the driving of the electric water pump, and before the warm-up is completed, the driving of the electric water pump is stopped to stop the cooling water. The circulation of the cooling water is stopped, and after the warm-up is completed, the electric water pump is driven to start the circulation of the cooling water. In the case of such a configuration, it can be determined whether the warm-up is completed based on the temperature data acquired by the temperature measuring means.

That is, in the latent heat storage device as described above, the cooling water circulation control means may include a temperature measurement means, and the cooling water circulation control may be performed based on the temperature data acquired by the temperature measurement means . The temperature measuring means in such a latent heat storage device may be configured to acquire the temperature data by measuring the temperature of the bore portion of the cylinder block or the latent heat storage material, for example . In this configuration, the temperature measuring means is a thermometer, temperature data is acquired by this thermometer, and cooling water circulation control is performed. That is, the drive of the electric water pump is stopped until the temperature data rises to a predetermined value, and the drive of the electric water pump is started when the temperature data exceeds the predetermined value. Here, the reason why the temperature measuring means (thermometer) measures the temperature of the bore portion of the cylinder block or the latent heat storage material is to directly measure the temperature of the portion that needs to be cooled after the warm-up is completed. is there. Note that if the latent heat storage material becomes too hot, the pressure in the latent heat storage material container may be increased or deteriorated, so it is necessary to cool the temperature so that the temperature does not rise above a predetermined value.

Further, the temperature measuring means may be configured to acquire the temperature data based on the temperature of cooling water or engine oil . In this case, the temperature of cooling water or engine oil measured by a normal engine is used as temperature data used for the warm-up completion determination.

Further, the temperature measuring means may be configured to calculate and acquire the temperature data based on engine load data . An engine mounted on a vehicle is usually provided with various sensors, and engine load data is acquired. From the engine load data, the temperature of each part of the engine can be estimated. Therefore, temperature data is acquired from engine load data having a correlation with the temperature of each part of the engine, and this temperature data is used for warm-up completion determination.

  The above configuration is a configuration in which temperature data is acquired and the circulation of the cooling water is controlled by a control means such as an ECU based on the temperature data. The configuration described below uses the properties of the latent heat storage material. Thus, the circulation of the cooling water is controlled.

That is, in the latent heat storage device as described above, the cooling water circulation control means enters a solid phase when the latent heat storage material of the latent heat storage material container flows in and the latent heat storage material nucleates from the supercooled state. It is characterized by being a bag-like part which forms the projection part which inhibits the circulation of the cooling water . The latent heat storage material is in a liquid phase when it is in a supercooled state, but when it is nucleated by using a nucleating means or the like, it causes a phase change to a solid phase while generating latent heat. The present invention pays attention to this point, and is configured to block the water jacket with the latent heat storage material in a solid state, inhibit the circulation of the cooling water, and prevent the heat from the latent heat storage material from being taken outside. .
The latent heat storage material emits latent heat during warm-up and changes phase to a solid phase, forming a protrusion to inhibit circulation of the cooling water. However, when warm-up is completed and the temperature rises, the liquid is stored again. Since the phase changes to the phase, the cooling water that circulates while maintaining a certain pressure can be circulated by pushing the bag-like portion away.

In such a latent heat storage device, a configuration can be adopted in which a shape-retaining member for the bag-shaped portion is disposed in the vicinity of the bag-shaped portion . By arranging such a shape-retaining member, the function of the protrusions to hinder the circulation of the cooling water can be enhanced, and the position thereof can be stabilized. However, the material and size of the shape-retaining member are determined so as not to hinder the circulation of the cooling water after the warm-up is completed.

In such a latent heat storage device, for example, the water jacket can be divided along the sliding direction of the piston, and the bag-like portion can be arranged for each divided water jacket . The cylinder block after completion of warm-up is required to be cooled on the side closer to the combustion chamber. Therefore, if the water jacket is divided in this way and the bag-like portion is arranged for each divided water jacket, the latent heat storage material changes from the solid phase to the liquid phase after the warm-up is completed on the side closer to the combustion chamber. The circulation of the cooling water can be resumed.

Furthermore, in such a latent heat storage device, the size and arrangement of the bag-like portion can be determined so as to come into contact with a location where the engine needs to be heated . If there is a place where cooling with cooling water is not desirable even after the warm-up is completed, increasing the size of the bag-like part in contact with the place will increase the latent heat storage material from the solid phase to the liquid phase. Even after the change, the flow of the cooling water at the location is hindered, so that the location can be warmed and kept warm.

If the latent heat storage device as described above is incorporated in a conventional engine, the engine of the present invention can be obtained.

  According to the present invention, since the cooling water circulation is stopped until the warm-up is completed at the time of cold start, the latent heat of the nucleated latent heat storage material is used to raise the temperature of the cylinder block without being taken away to the outside. Therefore, early warm-up, reduction of friction, and improvement of fuel consumption can be achieved.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a schematic configuration of an engine 2 equipped with the latent heat storage device 1 of the present invention, and (a) is a diagram of the cylinder block 3 with the cylinder head removed as viewed from the cylinder head mounting side. (B) is the XX sectional view taken on the line in (a). The latent heat storage device 1 includes a latent heat storage material 4 enclosed therein, a latent heat storage material container 6 accommodated in a water jacket 5 formed in the cylinder block 3 of the engine 2, and a thermometer 7. . The thermometer 7 corresponds to the temperature measuring means in the present invention, is attached to the latent heat storage material container 6, and measures the temperature of the latent heat storage material 4. The thermometer 7 is connected to an ECU 8, and the ECU 8 is further connected to an electric water pump 10 that circulates cooling water that has passed through the radiator 9 to the water jacket 5.

  The latent heat storage material container 6 is arranged on the bore side wall 3 a side of the cylinder block 3 in the water jacket 5, and the cooling water is circulated between the cylinder block outer wall 3 b and the latent heat storage material container 6. The latent heat storage material 4 enclosed in the latent heat storage material container 6 is sodium acetate trihydrate. Sodium acetate trihydrate has a melting point of about 58 ° C. and can maintain a supercooled state up to about −20 ° C. to −30 ° C. This latent heat can be used for heating and warming up the engine 2. Such a latent heat storage material 4 is in a supercooled state before the engine is started (when cold). A nucleation device 11 is attached to the latent heat storage material container 6, and the latent heat storage material 4 is nucleated based on a nucleation command from the ECU 8 based on the ON signal of the ignition 12 to generate heat.

  The operation of the latent heat storage device 1 configured as described above will be described. When the ignition 12 is turned on, the ECU 8 acquires temperature data from the thermometer 7 and determines whether or not the temperature is equal to or higher than the temperature T. This temperature T is a reference temperature for determining whether or not the engine 2 is in the warm-up completion state, and is stored in advance in the ECU 8.

  When the temperature is equal to or lower than the temperature T, the ECU 8 issues a nucleation command to the nucleation device 11. Thus, after the engine 2 is started, the engine 2 is warmed up by the latent heat of the latent heat storage material 4 in addition to the temperature rise due to the combustion of the engine 2 itself. Further, when the temperature is equal to or lower than the temperature T, the ECU 8 keeps the electric water pump 10 in a driving stopped state. By this measure, the cooling water does not circulate, so that heat is not carried away by the cooling water, and an efficient warm-up can be achieved.

  FIG. 2 is a graph showing how the temperature of the bore side wall 3a rises when a conventional latent heat storage material is accommodated in a cylinder block and circulation of cooling water is started simultaneously with engine start and this embodiment is compared. It is. In FIG. 2, a solid line shows a curve indicating a conventional example, but since the cooling water is constantly circulated after the engine is started, a temperature drop due to the removal of heat by the cooling water is observed. On the other hand, in the present embodiment, the broken line indicates that the temperature of the bore side wall 3a rises quickly because the circulation of the cooling water is stopped at the cold start. For this reason, early warm-up can be realized in the area shown by hatching in FIG. 2, and the time until the warm-up is completed can be shortened.

  The ECU 8 starts driving the electric water pump 10 after the warm-up is completed, that is, when it is determined that the temperature data from the thermometer 7 is equal to or higher than the temperature T, and circulates the cooling water cooled by the radiator 9 to To cool down. At the same time, the temperature rise and pressure rise of the latent heat storage material 4 are also suppressed.

  The latent heat storage material 4 that has generated heat by generating nuclei receives heat that will be generated by the engine 2 after warming up, returns to the supercooled state again, and prepares for the next nucleation.

  As described above, in this embodiment, the temperature data is acquired, and the circulation of the cooling water is stopped until the warm-up is completed. Here, the temperature data is acquired by the thermometer 7, but this temperature data can also be acquired by other means. That is, since it is only necessary to acquire data that can determine whether the engine 2 has been warmed up, for example, the temperature data can be acquired based on the temperature of cooling water or engine oil. If it is a normal engine mounted on a vehicle, it is equipped with a water temperature meter that measures the temperature of the cooling water and an oil temperature meter that measures the temperature of the engine oil. You may make it perform drive control of the electric water pump 10 based on data.

  In addition, various sensors are attached to the engine mounted on the vehicle, and the engine load can be calculated from these sensors. Since this engine load data has a correlation with the temperature of each part of the engine, the engine load The temperature data may be calculated based on the data, and drive control of the electric water pump 10 may be performed based on the temperature data.

  Furthermore, in this embodiment, the circulation of the cooling water is controlled by controlling the driving of the electric water pump 10, but the control target by the ECU 8 may be a valve body that opens and closes using a solenoid or the like. That is, it is possible to control the circulation of the cooling water by closing the water jacket with the valve body. When such a valve body is an object to be controlled by the ECU 8, a mechanical pump that circulates cooling water can be employed.

  Next, a second embodiment of the present invention will be described with reference to FIGS. The latent heat storage device 20 of the present embodiment is similar to the latent heat storage device 1 of the first embodiment, in which the latent heat storage material 4 is enclosed and the latent heat stored in the water jacket 5 formed in the cylinder block 3 of the engine 2. A heat storage material container 6 is provided. The latent heat storage material container 6 is a container made of a hard resin having a hole 21, and a resin film 22 is attached to the hole 21. The resin film 22 forms a bag-like portion in the present invention, and the latent heat storage material 4 in the latent heat storage material container 6 flows into the resin film 22. The resin film 22 is sized to close the water jacket 5 when the latent heat storage material 22 is filled therein. Further, a rubber shape-retaining member 23 having elasticity that keeps the shape of the resin film 22 is mounted around the resin film 22.

  The latent heat storage material container 6 is equipped with a nucleation means 11 for nucleating the latent heat storage material 4, and the nucleation means 11 is connected to an ECU 8 connected to an ignition 12 in the first embodiment. Same as the case. However, the engine 2 of this embodiment is equipped with a mechanical water pump 27 instead of the electric water pump 10 in the first embodiment. Constituent elements common to the latent heat storage device 1 of the first embodiment are denoted by common reference numerals in the drawings, and detailed description thereof is omitted.

  In the latent heat storage device 20 configured as described above, when the ignition 12 is turned on during cold start, the ECU 8 issues a nucleation command to the nucleation device 11 and the latent heat storage material 4 starts nucleation. At this time, the latent heat storage material 4 in the supercooled state changes from the liquid phase to the solid phase and forms the protrusion 24. As a result, the water jacket 5 is closed as shown in FIG. 4A, and the circulation of the cooling water is hindered. That is, the protrusion 24 functions as a cooling water valve. At this time, the latent heat storage material 4 emits latent heat, but since heat is not carried away by the cooling water, warm-up of the engine 2 can be promoted.

  Thus, the latent heat storage device 20 of the present embodiment stops the circulation of the cooling water when the latent heat storage material 4 changes to the solid phase, but the latent heat is increased when the engine 2 is warmed up and the temperature further rises. The heat storage material 4 again causes a phase change in the liquid phase. When the latent heat storage material 4 is in a liquid phase, the resin film 22 is pushed by the flow of cooling water as shown by an arrow 25 in FIG. 4B, and the cooling water circulates in the water jacket 5. Thereby, each part of the engine can be actively cooled.

  As described above, in the latent heat storage device 22 of the present embodiment, the circulation of the cooling water is controlled using the phase change of the latent heat storage material 4. The resin film 22 that forms the protrusion 24 that controls the circulation of the cooling water can be appropriately changed in its location in consideration of the cooling characteristics of the engine 2 and the like.

  For example, a configuration as shown in FIG. FIGS. 5A and 5B are explanatory views in which the respective sections are cross-sectioned with each other in order to explain the arrangement position of the protrusion 24. 5A is a cross-sectional view taken along line AA in FIG. 5B, FIG. 5B is a cross-sectional view taken along line BB in FIG. 5C, and FIG. It is CC sectional view taken on the line in (a). In the example shown in FIG. 5, the latent heat storage material container 6 is disposed on the cylinder block outer wall 3 b side in the water jacket 5, and the cooling water is circulated between the bore side wall 3 a of the cylinder block 3 and the latent heat storage material container 6. It is supposed to let you. Therefore, an opening 26 is provided for introducing cooling water supplied from the outside into the water jacket 5 as indicated by an arrow 27. With such a configuration, the cooling water circulation can be stopped by the protrusion 24 at the time of cold start, and the bore side wall 3a can be actively cooled by the cooling water after warming up.

  FIG. 6 shows still another configuration, FIG. 6 (a) is a cross-sectional view taken along the line DD in FIG. 6 (b), and FIG. 6 (b) is an EE in FIG. 6 (c). FIG. 6C is a sectional view taken along line FF in FIG. 6A. In the example shown in FIG. 6, the latent heat storage material container 6 is arranged on the bottom side in the water jacket 5, and the cooling water is circulated on the upper side of the latent heat storage material container 6. With such a configuration, the cooling water circulation can be stopped by the protrusion 24 at the time of cold start, and the upper portion of the cylinder block 3 that is susceptible to the influence of combustion heat by the cooling water after warm-up is positive. Can be cooled to.

  FIG. 7 shows still another configuration. FIG. 7A is a cross-sectional view taken along line GG in FIG. 7B, and FIG. 7B is a cross-sectional view taken along line H-H in FIG. FIG. 7C is a cross-sectional view taken along the line II in FIG. 7A. In the example shown in FIG. 7, the water jacket 5 is divided along the sliding direction of the piston, and the resin film 22 is arranged for each of the divided water jackets 5 a, 5 b, and 5 c, and the protrusion 24 is formed. Is. With such a configuration, it is possible to circulate the cooling water only in a portion where cooling with the cooling water is necessary, and to stop the circulation of the cooling water by the protrusion 24 at the cold start. Further, the latent heat storage material container 6 having a shape as shown in FIG. 7 can also obtain the effect of a water jacket spacer, and can be expected to improve the fuel efficiency after warming up.

  FIG. 8 shows still another configuration. FIG. 8 (a) is a cross-sectional view taken along the line JJ in FIG. 8 (b), and FIG. 8 (b) is a cross-sectional view taken along line KK in FIG. FIG. 8C is a cross-sectional view taken along line LL in FIG. 8A. In the example shown in FIG. 8, the size and arrangement are determined so that the protrusions 24 a, 24 b, and 24 c come into contact with the heating-necessary portions of the engine 2. With such a configuration, it is possible to increase the contact area between the protrusions 24a to 24c in which the latent heat storage material 4 is sealed and the location where the cylinder block 3 is to be overheated, so that the heat generated by the latent heat storage material 4 is transferred to the cylinder block. 3 can be transmitted efficiently and warm-up can be promoted. Further, if the size of the protruding portion 24 is increased, the flow of the cooling water can be prevented even after the warm-up is completed, and it can be used as a guide for the cooling water, and the flow of the cooling water can be controlled. Further, the effect of the water jacket spacer is obtained as in the example shown in FIG.

  The above-described embodiments are merely examples for carrying out the present invention, and the present invention is not limited thereto. Various modifications of these embodiments are within the scope of the present invention. It is apparent from the above description that various other embodiments are possible within the scope. For example, the material of the latent heat storage material container 6 may be made of metal instead of the hard resin.

It is a figure which shows schematic structure of the engine which mounted | wore the latent heat storage apparatus of Example 1, (a) is the figure which looked at the cylinder block of the state which removed the cylinder head from the cylinder head mounting side, (b) It is XX sectional drawing in a). It is the graph which showed the mode of the temperature rise of the bore | boa side wall of Example 1 compared with the prior art example. It is a figure which shows schematic structure of the engine which mounted | wore the latent heat storage apparatus of Example 2, and was the figure which looked at the cylinder block of the state which removed the cylinder head from the cylinder head mounting side. (A) is explanatory drawing which shows the state which a projection part obstruct | occludes a water jacket, (b) is explanatory drawing which shows a mode that a cooling water pushes away a projection part and distribute | circulates the inside of a water jacket. (A)-(b) is explanatory drawing which made each part the cross section mutually in order to demonstrate the arrangement position of a projection part. (A)-(b) is explanatory drawing which made each part a cross section mutually in order to demonstrate the arrangement position of another protrusion part. (A)-(b) is explanatory drawing which made each part a cross section mutually in order to demonstrate the arrangement position of another protrusion part. (A)-(b) is explanatory drawing which made each part a cross section mutually in order to demonstrate the arrangement position of another protrusion part.

Explanation of symbols

1, 20 Latent heat storage device 2 Engine 3 Cylinder block 3a Bore side wall 3b Cylinder block outer wall 4 Latent heat storage material 5 Water jacket 6 Latent heat storage material container 7 Thermometer 8 ECU
9 Radiator 10 Electric water pump 11 Nucleation device 12 Ignition 22 Resin film 23 Shape retaining member 24, 24a, 24b, 24c Protrusion 27 Mechanical water pump

Claims (7)

A latent heat storage material container enclosed in a latent heat storage material and housed in a water jacket formed in the cylinder block of the engine;
Cooling water circulation control means for controlling the circulation of the cooling water in the water jacket;
With
The cooling water circulation control means is a protrusion that inhibits the circulation of the cooling water when the latent heat storage material of the latent heat storage material container flows in and the latent heat storage material nucleates from the supercooled state to become a solid phase. A latent heat storage device, wherein the latent heat storage device is a bag-like portion forming a portion. The latent heat storage device according to claim 1,
A latent heat storage device in which a shape-retaining member for the bag-like part is disposed in the vicinity of the bag-like part. The latent heat storage device according to claim 1 or 2,
A latent heat storage device, wherein the water jacket is divided along a sliding direction of a piston, and the bag-like portion is arranged for each divided water jacket. In the latent heat storage device according to any one of claims 1 to 3,
A latent heat storage device characterized in that the size and arrangement of the bag-like portion are determined so as to come into contact with a location where the engine needs to be heated. In the latent heat storage device according to any one of claims 1 to 4,
The latent heat storage material container is arranged on the cylinder block outer wall side in the water jacket, and the cooling water is circulated between a bore side wall of the cylinder block and the latent heat storage material container. In the latent heat storage device according to any one of claims 1 to 3,
The latent heat storage material container is arranged on the bottom side in the water jacket, and the cooling water is circulated on the upper side of the latent heat storage material container. An engine incorporating the latent heat storage device according to any one of claims 1 to 6 .

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