JP6950650B2 - Rotating piston engine cooling system - Google Patents

Description

The present invention relates to a cooling device for a rotary piston type engine.

As a conventional rotary piston type engine, for example, Japanese Patent Application Laid-Open No. 2001-241303 (Patent Document 1) provides a plurality of pistons sliding in a cylindrical housing with the central axis of the housing as the center of rotation. A configuration is disclosed in which the output shaft is rotated by burning fuel in a combustion chamber formed by an inner peripheral surface of the housing and a plurality of pistons that rotate and slide in the housing.

Japanese Unexamined Patent Publication No. 2001-241303

However, in the rotary piston type engine as described above, it is required to appropriately cool the inside thereof. For example, it is conceivable to cool the inside of the engine by supplying hydraulic oil to the inside of the engine, but since the piston rotates around the axis, the hydraulic oil supplied to the inside of the engine is moved to the outside by centrifugal force. Because it moves, it may not be possible to cool the engine properly.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a cooling device for a rotary piston type engine that efficiently cools an engine during operation of the engine.

A cooling device for a rotary piston engine according to a certain aspect of the present invention includes a housing, a first piston member rotatably supported in the housing, and a second piston member rotatably supported in the housing. It is a cooling device for a rotary piston type engine including a combustion chamber for burning fuel by an inner peripheral surface of a housing, a first piston member, and a second piston member. The first piston member has a piston piece whose inside is hollow due to the provision of a first recess opened in a predetermined first direction. The second piston member has a piston piece whose inside is hollow due to the provision of a second recess opened in a predetermined second direction. The engine has a stop device that stops one of the first piston member and the second piston member when the fuel burns in the combustion chamber. The cooling device includes a supply unit that supplies the cooling medium to the housing, and a discharge unit that is provided in the housing and discharges the cooling medium supplied to the housing to at least one of the first recess and the second recess. The discharge portion is provided at a position facing the opening of one of the first recess and the second recess, which is in a stopped state when fuel is burned in the combustion chamber.

In this way, the cooling medium is supplied from the discharge portion to one of the recesses in the stopped state, so that the temperature rise of one of the first piston member and the second piston member in the stopped state is suppressed. be able to. Further, when the piston member is in the stopped state, the contact period between the piston member and the cooling medium is longer than when the piston member is in the rotating state, and the engine can be cooled efficiently.

Preferably, the discharge portion faces at least the wall surface portion of the wall surface formed in one of the recesses, which is closer to the combustion chamber in which the fuel burns.

In this way, it is possible to suppress the temperature rise of at least the wall surface portion of the wall surface formed in the recessed portion that is in the stopped state, which is closer to the combustion chamber where the fuel is burned. Therefore, the engine can be cooled efficiently.

More preferably, the first piston member has a plurality of piston pieces. The discharge portion is located at a position facing at least the first recess of the piston piece forming the combustion chamber in which the fuel burns, among the first recesses, when the first piston member is stopped due to the combustion of fuel in the combustion chamber. Provided.

In this way, it is possible to suppress the temperature rise of the piston piece forming the combustion chamber in which the fuel of the plurality of piston pieces is burned. Therefore, the engine can be cooled efficiently.

More preferably, the cooling device further includes a discharge amount control device that controls the discharge amount of the cooling medium from the discharge unit. The discharge amount control device increases the discharge amount when the temperature of at least one of the first piston member and the second piston member is higher than the threshold value than when the temperature is lower than the threshold value.

By doing so, it is possible to control the discharge amount so that an appropriate cooling amount can be obtained according to the temperatures of the first piston member and the second piston member, so that the engine can be cooled efficiently.

According to the present invention, it is possible to provide a cooling device for a rotary piston type engine that efficiently cools an engine during operation of the engine.

It is a figure which shows an example of the schematic structure of the power generation system in this embodiment. It is a perspective view which shows a part of the structure of a power generation system. It is a figure which shows an example of the structure of the piston member provided in the engine. It is a figure for demonstrating an example of the operation of each component member at the time of burning fuel in a combustion chamber A. It is a figure for demonstrating an example of the operation of each component member at the time of burning fuel in a combustion chamber D. It is a figure for demonstrating an example of the change of the process in each combustion chamber. It is a perspective view of the 1st piston member. It is a perspective view of the 2nd piston member. It is a figure for demonstrating an example of the structure of the piping included in a cooling device. It is a figure for demonstrating the position of two openings provided on the surface facing the 1st MG. It is a figure for demonstrating the position of the two openings provided on the surface facing the 2nd MG. It is a figure for demonstrating the structure of the discharge part set in the housing. It is a figure for demonstrating the structure of the discharge part set in the housing in the modification. It is a flowchart which shows an example of the control process (the 1) of the oil pump executed by the control device in the modification. It is a figure which shows the high temperature region and low temperature region set by the rotation speed and the fuel supply amount. It is a flowchart which shows an example of the control process (the 2) of the oil pump executed by the control device in the modification. It is a figure for demonstrating the control which operates an oil pump intermittently.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are designated by the same reference numerals. Their names and functions are the same. Therefore, detailed explanations about them will not be repeated.

<About the outline configuration of the power generation system 1>
Hereinafter, the configuration and operation of the power generation system 1 using the rotary piston type engine according to the present embodiment will be described. FIG. 1 is a diagram showing an example of a schematic configuration of a power generation system 1 according to the present embodiment. FIG. 2 is a perspective view showing a part of the configuration of the power generation system 1. As shown in FIGS. 1 and 2, the power generation system 1 includes a rotary piston type engine (hereinafter, simply referred to as an engine) 2, a cooling device 50, a first MG (Motor Generator) 61, and a second MG (Motor Generator). ) 62, the first inverter 71, the second inverter 72, the battery 80, the load 90, the first resolver 101, the second resolver 102, and the control device 200.

<About the configuration of engine 2>
In the present embodiment, the engine 2 is a rotating piston type internal combustion engine. For example, gas, gasoline, light oil, or the like is used as the fuel for the engine 2. The engine 2 includes a housing 4, an intake pipe 6, an exhaust pipe 8, an injector 10, a throttle valve 12, a throttle motor 14, a first output shaft 16, and a second output shaft 18.

One end of the intake pipe 6 is connected to an intake port (not shown) of the housing 4. An air cleaner (not shown) is connected to the other end of the intake pipe 6, for example. The air cleaner removes foreign matter from the air sucked from the outside of the engine 2. While the engine 2 is operating, the air sucked from the air cleaner flows through the intake pipe 6. The air flowing through the intake pipe 6 circulates in the intake port of the housing 4.

The throttle valve 12 is provided in the intake pipe 6 and limits the flow rate of air flowing through the intake pipe 6. The opening degree (throttle opening degree) of the throttle valve 12 is adjusted by the throttle motor 14 that operates in response to the control signal TH from the control device 200.

The injector 10 is provided on the upstream side of the throttle valve 12 of the intake pipe 6, and injects fuel (for example, gas) into the intake pipe 6 in response to the control signal INJ from the control device 200. The injected fuel is mixed with air in the intake pipe 6 and flows to the intake port of the housing 4.

The outer peripheral portion of the housing 4 is formed in a cylindrical shape as shown in FIG. 2, and the inner peripheral portion thereof is also formed in a cylindrical shape. The housing 4 houses a first piston member connected to the first output shaft 16 and a second piston member connected to the second output shaft 18 inside the housing 4.

One end of the exhaust pipe 8 is connected to an exhaust port (not shown) of the housing 4. For example, an exhaust treatment device (not shown) is connected to the other end of the exhaust pipe 8. During the operation of the engine 2, the exhaust generated by the combustion in the housing 4 flows from the exhaust port of the housing 4 to the exhaust pipe 8. The exhaust gas flowing through the exhaust pipe is purified by the exhaust treatment device and discharged to the outside of the engine 2.

<About the internal structure of engine 2>
Hereinafter, an example of the internal structure of the engine 2 will be described with reference to FIG. FIG. 3 is a diagram showing an example of the configuration of a piston member provided inside the engine.

As shown in FIG. 3, the first piston member 24 and the second piston member 28 are housed in the housing 4 in combination. The first piston member 24 includes a first rotating body 24a and a first wall surface member 24b. The second piston member 28 includes a second rotating body 28a and a second wall surface member 28b. The first wall surface member 24b corresponds to a piston piece of the first piston member 24. The second wall surface member 28b corresponds to a piston piece of the second piston member 28.

The first rotating body 24a and the second rotating body 28a are rotatably supported by the housing 4 so that the centers of rotation coincide with each other, and one end surface of the first rotating body 24a and one of the second rotating body 28a. It is provided so as to face the end face.

The first rotating body 24a and the second rotating body 28a are formed so as to have a slope portion in the cross section including the center of rotation thereof. As a result, in a state where the first rotating body 24a and the second rotating body 28a are combined, a recess having a V-shaped cross section is formed between the first rotating body 24a and the second rotating body 28a in the circumferential direction. Is formed in.

The first rotating body 24a is provided with a first wall surface member 24b that extends from the center of rotation toward the inner peripheral surface of the housing 4 and whose end abuts on the inner peripheral surface of the housing 4. The first wall surface member 24b is composed of two triangular plate-shaped members. The two triangular plate-shaped members of the first wall surface member 24b are provided on the first rotating body 24a so as to be symmetrical with respect to the center of rotation.

The second rotating body 28a is provided with a second wall surface member 28b that extends from the center of rotation toward the inner peripheral surface of the housing 4 and whose end abuts on the inner peripheral surface of the housing 4. The second wall surface member 28b is composed of two triangular plate-shaped members having the same shape as the plate-shaped member constituting the first wall surface member 24b described above. The two triangular plate-shaped members of the second wall surface member 28b are provided on the second rotating body 28a so as to have a positional relationship symmetrical with respect to the center of rotation.

The triangular plate-shaped members of the first wall surface member 24b and the second wall surface member 28b are the first rotating body 24a and the first rotating body 24a in a state where the first piston member 24 and the second piston member 28 are housed in the housing 4. It is formed so as to match the cross-sectional shape of a triangle formed by the recess between the two rotating bodies 28a and the inner peripheral surface of the housing 4. Further, the outer peripheral portions of the triangular plate-shaped members of the first wall surface member 24b and the second wall surface member 28b are configured to be slidable with the inner peripheral surface of the housing 4.

Seals and the like are appropriately provided on the contact portion and the sliding portion between the members. The first output shaft 16 is connected to the first rotating body 24a so that the centers of rotation coincide with each other. The second output shaft 18 is connected to the second rotating body 28a so that the centers of rotation coincide with each other. Further, for example, one-way clutches 22 and 26 are provided between each of the first rotating body 24a and the second rotating body 28a and the housing 4. The one-way clutch 22 allows rotation of the first rotating body 24a only in a predetermined rotation direction in the housing 4, and suppresses rotation in a direction opposite to the predetermined rotation direction. Similarly, the one-way clutch 26 allows rotation of the second rotating body 28a only in a predetermined rotation direction in the housing 4, and suppresses rotation in a direction opposite to the predetermined rotation direction.

<About configurations other than engine 2>
Returning to FIGS. 1 and 2, the configuration of the power generation system 1 other than the engine 2 will be described below.

Both the first output shaft 16 and the second output shaft 18 rotate due to the combustion of fuel in the housing 4. The first output shaft 16 is connected to the rotation shaft of the first MG61. The second output shaft 18 is connected to the rotation shaft of the second MG 62.

The first MG61 and the second MG62 are, for example, both three-phase AC rotary electric machines. Both the first inverter 71 and the second inverter 72 are power conversion devices configured to enable power conversion between DC power and AC power.

The first MG 61 is electrically connected to the first inverter 71. The first inverter 71 is controlled by the control signal INV1 from the control device 200. That is, the electric power transferred between the first MG 61 and the first inverter 71 is controlled by the control signal INV1 from the control device 200.

The control device 200 controls the first inverter 71 so that the regenerative torque is generated in the first MG 61, for example. At this time, the regenerative power generated in the first MG 61 is converted from AC power to DC power in the first inverter 71 and supplied to the battery 80. The battery 80 is charged by the DC power supplied from the first inverter 71. Alternatively, the control device 200 controls the first inverter 71 so that the drive torque is generated in the first MG 61. At this time, the power of the battery 80 is converted from DC power to AC power in the first inverter 71 and supplied to the first MG 61.

The second MG 62 is electrically connected to the second inverter 72. The second inverter 72 is controlled by the control signal INV2 from the control device 200. That is, the electric power transferred between the second MG 62 and the second inverter 72 is controlled by the control signal INV2 from the control device 200.

The control device 200 controls the second inverter 72 so that the regenerative torque is generated in the second MG 62, for example. At this time, the regenerative power generated in the second MG 62 is converted from AC power to DC power in the second inverter 72 and supplied to the battery 80. The battery 80 is charged by the DC power supplied from the second inverter 72. Alternatively, the control device 200 controls the second inverter 72 so that the drive torque is generated in the second MG 62. At this time, the power of the battery 80 is converted from DC power to AC power in the second inverter 72 and supplied to the second MG 62.

The battery 80 is a DC power source composed of a secondary battery such as a nickel hydrogen battery or a lithium ion battery, for example. The battery 80 may be a power storage device capable of storing DC power supplied from the first inverter 71 or the second inverter 72, and for example, a capacitor or the like may be used instead of the battery 80.

The cooling device 50 supplies a cooling medium into the housing 4 of the engine 2 to cool the engine 2. In the present embodiment, it will be described that a hydraulic oil having a function of lubrication in addition to cooling is used as a cooling medium. The cooling device 50 includes an oil pump 38, a first pipe 30 for supplying hydraulic oil to the first piston member, a second pipe 32 for supplying hydraulic oil to the second piston member, a first pipe 30, and a first pipe 30. The third pipe 34 connecting the four pipes 36 and the fourth pipe 36 having one end connected to the second pipe 32 and the other end connected to the oil pump 38 are included.

The oil pump 38 is, for example, an electric oil pump and operates in response to a control signal PO from the control device 200. The oil pump 38 is a supply source that sucks oil from an oil pan (oil storage portion) (not shown) and supplies hydraulic oil to the fourth pipe 36. The hydraulic oil supplied to the housing 4 shall be returned to the oil pan.

The operation of the power generation system 1 is controlled by the control device 200. The control device 200 includes a CPU (Central Processing Unit) that performs various processes, a memory that includes a ROM (Read Only Memory) that stores programs and data, a RAM (Random Access Memory) that stores the processing results of the CPU, and the like. Includes input / output ports (neither shown) for exchanging information with the outside. The above-mentioned sensors (for example, the first resolver 101 and the second resolver 102) are connected to the input port. Devices to be controlled (for example, engine 2, oil pump 38, first inverter 71, second inverter 72, etc.) are connected to the output port.

The control device 200 controls various devices so that the power generation system 1 is in a desired operating state based on the signals from each sensor and the device, and the map and the program stored in the memory. Note that various controls are not limited to software processing, but can also be processed by dedicated hardware (electronic circuits).

The first resolver 101 detects the rotation angle (hereinafter, referred to as the rotation angle CA1) of the rotation axis (first output shaft 16) of the first MG61. The first resolver 101 transmits a signal indicating the detected rotation angle CA1 to the control device 200.

The second resolver 102 detects the rotation angle (hereinafter, referred to as the rotation angle CA2) of the rotation axis (second output shaft 18) of the second MG 62. The second resolver 102 transmits a signal indicating the detected rotation angle CA2 to the control device 200.

<About the operation of the power generation system 1>
The operation of the power generation system 1 having the above configuration will be described with reference to FIGS. 4 to 6.

FIG. 4 is a diagram for explaining an example of the operation of each component member when fuel is burned in the combustion chamber A. FIG. 5 is a diagram for explaining an example of the operation of each component member when fuel is burned in the combustion chamber D.

FIG. 4 shows a cross section of a central portion of the housing 4 (for example, a contact portion between the first rotating body 24a and the second rotating body 28a). As shown in FIG. 4, four combustion chambers A to D are formed in the housing 4 by the inner peripheral surface of the housing 4, the first piston member 24, and the second piston member 28.

In FIG. 4, the one-way clutches 22 and 26 suppress the counterclockwise rotation of the first piston member 24 and the second piston member 28, and allow the clockwise rotation. The same applies to FIGS. 5, 10, 11 and 17.

In the combustion chamber A shown in FIG. 4, the air-fuel mixture of the compressed air and the fuel becomes an expansion stroke in which the air-fuel mixture is ignited by self-ignition. That is, when the fuel burns in the combustion chamber A, the counterclockwise movement of the first piston member 24 is suppressed by the one-way clutch 22, so that the second piston member 28 is maintained while the rotational position of the first piston member 24 is maintained. Only rotates in the direction of the dashed arrow, and the volume of the combustion chamber A increases with the expansion of the gas in the combustion chamber A.

In the combustion chamber B shown in FIG. 4, the expanded exhaust gas is discharged from the exhaust pipe 8. That is, when the second piston member 28 rotates in the direction of the broken arrow arrow due to the combustion of fuel in the combustion chamber A, the rotational position of the first piston member 24 is maintained, so that the volume of the combustion chamber B decreases. At this time, the combustion chamber B communicates with the exhaust pipe 8. Therefore, the exhaust gas in the combustion chamber B is discharged to the exhaust pipe 8 as the volume of the combustion chamber B decreases.

In the combustion chamber C shown in FIG. 4, the intake stroke is such that the air-fuel mixture is sucked from the intake pipe 6. That is, when the second piston member 28 rotates in the direction of the broken arrow arrow due to the combustion of fuel in the combustion chamber A, the rotational position of the first piston member 24 is maintained, so that the volume of the combustion chamber C increases. At this time, the combustion chamber C communicates with the intake pipe 6 while the second piston member 28 is rotating in the direction of the broken line arrow. Therefore, as the volume of the combustion chamber C increases, the air-fuel mixture is sucked into the combustion chamber C from the intake pipe 6.

In the combustion chamber D shown in FIG. 4, the compression stroke is such that the air-fuel mixture sucked from the intake pipe 6 is compressed. That is, when the second piston member 28 rotates in the direction of the broken arrow arrow due to the combustion of fuel in the combustion chamber A, the rotational position of the first piston member 24 is maintained, so that the volume of the combustion chamber D decreases. At this time, since the combustion chamber D does not communicate with either the intake pipe 6 or the exhaust pipe 8, the air-fuel mixture in the combustion chamber D is compressed by the decrease in the volume of the combustion chamber D.

Then, when a clockwise force acts on the first piston member 24 due to the increase in the pressure in the combustion chamber D, the first piston member 24 rotates, and the positions of the first piston member 24 and the second piston member 28 are located. The relationship is the positional relationship shown in FIG.

FIG. 5 shows a cross section of the central portion of the housing 4 as in FIG. The configuration of the engine 2 shown in FIG. 5 has a positional relationship between the first piston member 24 and the second piston member 28 and the positions and volumes of the combustion chambers A to D as compared with the configuration of the engine 2 shown in FIG. The same is true except that

In the combustion chamber D shown in FIG. 5, the expansion stroke is performed after the compression stroke. That is, in the combustion chamber D, the air-fuel mixture of the compressed air and the fuel is ignited by self-ignition. When the fuel burns in the combustion chamber D, the counterclockwise movement of the second piston member 28 is suppressed by the one-way clutch 26, so that only the first piston member 24 can maintain the rotational position of the second piston member 28. It rotates clockwise, and the volume of the combustion chamber D increases as the gas in the combustion chamber D expands.

In the combustion chamber A shown in FIG. 5, the exhaust stroke is performed after the expansion stroke. That is, when the first piston member 24 rotates clockwise due to the combustion of fuel in the combustion chamber D, the rotational position of the second piston member 28 is maintained, so that the volume of the combustion chamber A decreases. At this time, the combustion chamber A communicates with the exhaust pipe 8. Therefore, the exhaust gas in the combustion chamber A is discharged to the exhaust pipe 8 as the volume of the combustion chamber A decreases.

In the combustion chamber B shown in FIG. 5, the intake stroke is performed after the exhaust stroke. That is, when the first piston member 24 rotates clockwise due to the combustion of fuel in the combustion chamber D, the rotational position of the second piston member 28 is maintained, so that the volume of the combustion chamber B increases. At this time, the combustion chamber B communicates with the intake pipe 6 while the first piston member 24 is rotating. Therefore, as the volume of the combustion chamber B increases, the air-fuel mixture is sucked into the combustion chamber B from the intake pipe 6.

In the combustion chamber C shown in FIG. 5, the compression stroke is performed after the intake stroke. That is, when the first piston member 24 rotates clockwise due to the combustion of fuel in the combustion chamber D, the rotational position of the second piston member 28 is maintained, so that the volume of the combustion chamber C decreases. At this time, since the combustion chamber C does not communicate with either the intake pipe 6 or the exhaust pipe 8, the air-fuel mixture in the combustion chamber C is compressed by the decrease in the volume of the combustion chamber C.

Then, when a clockwise force acts on the second piston member 28 due to the increase in the pressure in the combustion chamber C, the second piston member 28 rotates, and the positions of the first piston member 24 and the second piston member 28 are located. The relationship is the positional relationship shown in FIG.

In this way, each time combustion is performed in any of the combustion chambers A to D, the first piston member 24 and the second piston member 28 rotate alternately to operate the engine 2. In this case, as shown in FIG. 4, when the fuel burns in the combustion chamber A or the combustion chamber C, the rotation of the second piston member 28 while the second piston member 28 rotates to a predetermined rotation position. Is generated by generating a regenerative torque for braking in the second MG 62. Similarly, as shown in FIG. 5, when the fuel burns in the combustion chamber B or the combustion chamber D, the rotation of the first piston member 24 is performed while the first piston member 24 rotates to a predetermined rotation position. Power is generated by generating a regenerative torque for braking in the first MG61.

That is, the first piston member 24 and the second piston member 28 rotate alternately to generate electricity in the first MG 61 and the second MG 62, and the generated AC power becomes DC power in the first inverter 71 and the second inverter 72. It is converted and supplied to the battery 80. In the present embodiment, the one-way clutches 22 and 26 correspond to a "stop device" that stops one of the first piston member 24 and the second piston member 28 when the fuel burns in the combustion chamber.

FIG. 6 is a diagram for explaining an example of a change in the process in each combustion chamber. As shown in FIG. 6, for example, in the stroke (1), the combustion chamber A becomes an expansion stroke, the combustion chamber B becomes an exhaust stroke, the combustion chamber C becomes an intake stroke, and the combustion chamber D becomes a compression stroke. The positional relationship between the first piston member 24 and the second piston member 28 is the positional relationship shown in FIG. Therefore, in the stroke (1), the second piston member 28 is rotated by the combustion in the combustion chamber A, and the regenerative torque is generated in the second MG 62.

In step (2), the combustion chamber A becomes the exhaust stroke, the combustion chamber B becomes the intake stroke, the combustion chamber C becomes the compression stroke, and the combustion chamber D becomes the expansion stroke. The positional relationship between the first piston member 24 and the second piston member 28 is the positional relationship shown in FIG. Therefore, in the process (2), the first piston member 24 is rotated by the combustion in the combustion chamber D, and the regenerative torque is generated in the first MG 61.

In the process (3), the combustion chamber A becomes the intake stroke, the combustion chamber B becomes the compression stroke, the combustion chamber C becomes the expansion stroke, and the combustion chamber D becomes the exhaust stroke. The positional relationship between the first piston member 24 and the second piston member 28 is the positional relationship shown in FIG. Therefore, in the process (3), the second piston member 28 is rotated by the combustion in the combustion chamber C, and the regenerative torque is generated in the second MG 62.

In step (4), the combustion chamber A becomes the compression stroke, the combustion chamber B becomes the expansion stroke, the combustion chamber C becomes the exhaust stroke, and the combustion chamber D becomes the intake stroke. The positional relationship between the first piston member 24 and the second piston member 28 is the positional relationship shown in FIG. Therefore, in the stroke (4), the first piston member 24 is rotated by the combustion in the combustion chamber B, and the regenerative torque is generated in the first MG 61.

After that, as long as the operation of the engine 2 continues, the operations of the steps (1) to (4) are repeated.

In the engine 2 included in the power generation system 1 having such a configuration, it is required to appropriately cool the inside thereof. When the hydraulic oil is supplied to the inside of the engine 2 by using the cooling device 50, the first piston member 24 and the second piston member 28 rotate around the axis, so that the hydraulic oil supplied to the inside of the engine 2 is used. It may move outward due to centrifugal force. Therefore, the engine 2 may not be cooled properly.

Therefore, in the present embodiment, the engine 2 and the cooling device 50 have the following features. That is, the first piston member 24 has a first wall surface member 24b whose inside is hollow due to the provision of a first recess opened in a predetermined first direction. The second piston member 28 has a second wall surface member 28b whose inside is hollow due to the provision of a second recess opened in a predetermined second direction. The cooling device 50 is provided in the housing 4, and includes a discharge portion for discharging the cooling medium supplied from the oil pump 38, which is a supply source, to the housing 4 into at least one of the first recess and the second recess. The discharge portion is provided at a position facing one of the first recess and the second recess, which is in a stopped state when fuel is burned in the combustion chamber. In the present embodiment, the predetermined first direction and the second direction are both directions parallel to the rotation axis.

In this way, hydraulic oil is supplied from the discharge portion to one of the recesses in the stopped state, so that the temperature of one of the stopped piston members of the first piston member 24 and the second piston member 28 rises. It can be suppressed. Further, when the piston member is in the stopped state, the contact period between the piston member and the hydraulic oil is longer than when the piston member is in the rotating state, and the engine 2 can be cooled efficiently.

Hereinafter, the detailed structures of the first recess and the second recess provided in the first piston member 24 and the second piston member 28, respectively, will be described with reference to FIGS. 7 and 8.

FIG. 7 is a perspective view of the first piston member 24. As shown in FIG. 7, the first piston member 24 is provided with four recesses 24c, 24d, 24e, and 24f that are opened in a direction opposite to the direction facing the second piston member 28. The recess 24c and the recess 24d are provided symmetrically with respect to the rotation axis, and the opening shape and the internal shape are also formed symmetrically. The recess 24e and the recess 24f are provided symmetrically with respect to the rotation axis, and the opening shape and the internal shape are also formed symmetrically. Of the recesses 24c, 24d, 24e, 24f, the recesses 24e and 24f are all formed so that the bottom reaches the inside of the first wall surface member 24b. That is, in the present embodiment, the recesses 24e and 24f correspond to the "first recess".

FIG. 8 is a perspective view of the second piston member 28. As shown in FIG. 8, the second piston member 28 is provided with four recesses 28c, 28d, 28e, 28f which are opened in a direction opposite to the direction facing the first piston member 24. The recess 28c and the recess 28d are provided symmetrically with respect to the rotation axis, and the opening shape and the internal shape are also formed symmetrically. The recess 28e and the recess 28f are provided symmetrically with respect to the rotation axis, and the opening shape and the internal shape are also formed symmetrically. Of the recesses 28c, 28d, 28e, and 28f, the recesses 28e and 28f are all formed so that the bottom reaches the inside of the second wall surface member 28b. That is, in the present embodiment, the recesses 28e and 28f correspond to the "second recess".

Next, an example of the configuration of the piping included in the cooling device 50 will be described. FIG. 9 is a diagram for explaining an example of the configuration of the piping included in the cooling device 50.

As shown in FIG. 9, the first pipe 30 includes a pipe 30a that branches from the third pipe 34 to the upper side of the first output shaft 16 and a pipe 30b that branches from the third pipe 34 to the lower side of the first output shaft 16. And include. One end of the pipe 30a is connected to a branch point with the third pipe 34, and the other end of the pipe 30a is an opening provided at a position above the first output shaft 16 on the surface of the housing 4 facing the first MG61. Connected to the part. One end of the pipe 30b is connected to a branch point with the third pipe 34, and the other end of the pipe 30b is an opening provided at a position below the first output shaft 16 on the surface of the housing 4 facing the first MG61. Connected to the part. The two openings provided on the surface of the housing 4 facing the first MG 61 are provided at positions symmetrical with respect to the axial center of the first output shaft 16.

The second pipe 32 includes a pipe 32a that branches from the fourth pipe 36 to the upper side of the second output shaft 18, and a pipe 32b that branches from the fourth pipe 36 to the lower side of the second output shaft 18. One end of the pipe 32a is connected to a branch point with the fourth pipe 36, and the other end of the pipe 32a is an opening provided at a position above the second output shaft 18 on the surface of the housing 4 facing the second MG 62. Connected to the unit. One end of the pipe 32b is connected to a branch point with the fourth pipe 36, and the other end of the pipe 32b is an opening provided at a position below the second output shaft 18 on the surface of the housing 4 facing the second MG 62. Connected to the part. The two openings provided on the surface of the housing 4 facing the second MG 62 are provided at positions symmetrical with respect to the axial center of the second output shaft 18.

FIG. 10 is a diagram for explaining the positions of the two openings provided on the surface facing the first MG61.

As shown in FIG. 10, on the surface of the housing 4 facing the first MG61, openings of recesses 24e and 24f are provided when the first piston member 24 is in a rotational position in which the first piston member 24 is stopped during the operation of the engine 2. Two openings 40a and 40b are provided at positions facing each other.

When the first piston member 24 and the second piston member 28 are in a positional relationship as shown in FIG. 10 during the operation of the engine 2, the combustion chamber A ignites and the fuel in the combustion chamber A burns. Combustion pressure acts on the first piston member 24 and the second piston member 28. Since the one-way clutch 22 suppresses the counterclockwise rotation of the first piston member 24, the first piston member 24 is maintained in a stopped state. At this time, the openings 40a and 40b are provided on the surface of the housing 4 facing the first MG61 at positions facing the openings of the recesses 24e and 24f provided in the first piston member 24, whereby the openings 40a and 40b are provided. The hydraulic oil can be directly supplied to the recesses 24e and 24f via the discharge portions 42a and 42b described later.

FIG. 11 is a diagram for explaining the positions of the two openings provided on the surface facing the second MG 62.

As shown in FIG. 11, on the surface of the housing 4 facing the second MG 62, openings of recesses 28e and 28f are provided when the second piston member 28 is in a rotational position in which the second piston member 28 is stopped during the operation of the engine 2. Two openings 40c and 40d are provided at positions facing each other.

When the first piston member 24 and the second piston member 28 are in a positional relationship as shown in FIG. 11 during the operation of the engine 2, the ignition is made in the combustion chamber D and the fuel in the combustion chamber D is burned. The combustion pressure acts on the first piston member 24 and the second piston member 28. Since the one-way clutch 26 suppresses the counterclockwise rotation of the second piston member 28, the second piston member 28 is maintained in the stopped state. At this time, the openings 40c and 40d are provided on the surface of the housing 4 facing the second MG 62 at positions facing the openings of the recesses 28e and 28f provided in the second piston member 28, so that the openings 40c and 40d The hydraulic oil can be directly supplied to the recesses 28e and 28f via the discharge portions 42c and 42d described later.

As shown in FIGS. 10 and 11, a plurality of discharge portions 42a, 42b, 42c, 42d are set inside the housing 4. Discharge portions 42a and 42b are connected to the openings 40a and 40b, respectively. The discharge portions 42a and 42b are configured to discharge hydraulic oil toward the recesses 24c, 24d, 24e, 24f provided in the first piston member 24 that is rotating or stopped. Further, discharge portions 42c and 42d are connected to the openings 40c and 40d, respectively. The discharge portions 42c and 42d are configured to discharge hydraulic oil toward the recesses 28c, 28d, 28e and 28f provided in the second piston member 28 that is rotating or stopped.

Next, the detailed structure of the discharge portions 42a, 42b, 42c, 42d will be described. Hereinafter, the structure of the discharge unit 42a will be described as an example, but the discharge units 42b, 42c, and 42d have the same structure as the discharge unit 42a. Therefore, the detailed explanation will not be repeated. FIG. 12 is a diagram for explaining the structure of the discharge portion 42a set in the housing 4.

As shown in FIG. 12, a discharge portion 42a is formed inside the housing 4. In this embodiment. The discharge portion 42a is a separate component from the housing 4, and is fixed so as to communicate with the opening 40a inside the housing 4. One end of the pipe 30a is connected to the opening 40a.

The discharge portion 42a has, for example, a hollow pipe shape, and has a bent portion that is bent in a predetermined direction in the middle.

As a predetermined direction at the bent portion of the discharge portion 42a, for example, when the first piston member 24 is in the stopped state, the wall surface formed in the recess 24e, which is closer to the combustion chamber where fuel is burned. It is set in a direction in which hydraulic oil can be discharged toward the wall surface of the. Therefore, the discharge portion 42a faces at least the wall surface portion of the wall surface formed in the recess 24e, which is closer to the combustion chamber where the fuel burns.

In the present embodiment, when the operation of the engine 2 is started, the control device 200 starts the control of the oil pump 38 so that the discharge amount becomes a predetermined discharge amount, and the operation of the engine 2 is stopped. The control of the oil pump 38 shall be continued until the oil pump 38 is controlled.

The operation of the cooling device 50 based on the above configuration will be described below. When the operation of the engine 2 is started, the operation of the oil pump 38 is started. Therefore, as shown in FIG. 1, the hydraulic oil is supplied from the oil pump 38 to the fourth pipe 36 and the pipe 32a of the second pipe 32. It is supplied to 32b and is supplied from the oil pump 38 to the pipes 30a and 30b of the first pipe 30 via the fourth pipe 36 and the third pipe 34.

The hydraulic oil supplied to the pipe 30a is discharged from the discharge portion 42a into the housing 4 via the opening 40a as shown in FIG. Similarly, the hydraulic oil supplied to the pipe 30b is discharged from the discharge portion 42b into the housing 4 via the opening 40b.

Therefore, during the operation of the engine 2, while the first piston member 24 is rotating, the hydraulic oil discharged from the discharge portions 42a and 42b is at least one of the recesses 24c, 24d, 24e and 24f shown in FIG. Supplied to either. As a result, the temperature rise of the first piston member 24 is suppressed.

Further, when the rotation of the first piston member 24 is stopped during the operation of the engine 2, the openings of the recesses 24e and 24f and the discharge portions 42a and 42b face each other as shown in FIG. Due to the positional relationship, a larger amount of hydraulic oil is supplied to the recesses 24e and 24f than when the first piston member 24 is rotating. Further, the hydraulic oil discharged from the discharge portions 42a and 42b is discharged toward the wall surface portion of the wall surfaces formed in the recesses 24e and 24f, which is closer to the combustion chamber where the fuel burns, and is therefore more efficient. The temperature rise of the first piston member 24 is often suppressed.

The hydraulic oil supplied to the pipe 32a is discharged from the discharge portion 42c into the housing 4 via the opening 40c. Similarly, the hydraulic oil supplied to the pipe 32b is discharged from the discharge portion 42d into the housing 4 via the opening 40d.

Therefore, during the operation of the engine 2, while the second piston member 28 is rotating, the hydraulic oil discharged from the discharge portions 42c and 42d is at least one of the recesses 28c, 28d, 28e and 28f shown in FIG. Supplied to either. As a result, the temperature rise of the second piston member 28 is suppressed.

Further, when the rotation of the second piston member 28 is stopped during the operation of the engine 2, the openings of the recesses 28e and 28f and the discharge portions 42c and 42d are in a positional relationship facing each other. 28e and 28f are supplied with a larger amount of hydraulic oil than when the second piston member 28 is rotating. Further, the hydraulic oil discharged from the discharge portions 42c and 42d is discharged toward the wall surface portion of the wall surfaces formed in the recesses 28e and 28f, which is closer to the combustion chamber where the fuel burns, and is therefore more efficient. The temperature rise of the second piston member 28 is often suppressed.

As described above, according to the cooling device 50 of the rotary piston type engine according to the present embodiment, the hydraulic oil is discharged from the discharge portion into the recess of the first piston member 24 and the second piston member 28 which is in the stopped state. Is supplied, so that it is possible to suppress a temperature rise of one of the first piston member 24 and the second piston member 28, which is in a stopped state. Further, when the piston member is in the stopped state, the contact period between the piston member and the cooling medium is longer than when the piston member is in the rotating state, and the engine can be cooled efficiently. Therefore, it is possible to provide a cooling device for a rotary piston type engine that efficiently cools the engine during operation of the engine.

Further, since the hydraulic oil is supplied from the discharge portion toward at least the wall surface portion of the wall surface formed in the recessed state in which the fuel is burned, which is closer to the combustion chamber, the temperature of the wall surface portion is increased. It can be suppressed. Therefore, the engine can be cooled efficiently.

Hereinafter, a modified example will be described.
In the above-described embodiment, the case where the number of piston members provided in the housing 4 is two has been described as an example, but the number of piston members provided in the housing 4 may be three or more. In this case, the fuel may be burned in any one of the plurality of combustion chambers formed in the housing, or the fuel may be burned in the plurality of combustion chambers.

Further, in the above-described embodiment, the case where the fuel is burned by self-ignition of the air-fuel mixture in the combustion chamber has been described as an example. May be configured to burn.

Further, in the above-described embodiment, the rotating cross section of the recess between the first rotating body 24a and the second rotating body 28a has a triangular shape, and the first piston member 24 and the second piston member 28 are both triangular plates. Although it has been described that the shaped members are provided as the first wall surface member 24b and the second wall surface member 28b, the shape of the rotating cross section of the recess and the shapes of the first wall surface member 24b and the second wall surface member 28b are limited to triangles. It may be a quadrangle, a semicircle, or a fan, for example.

Further, in the above-described embodiment, the injector 10 has been described as injecting fuel into the intake pipe 6, but for example, the injector 10 may be configured to directly inject fuel into the combustion chamber of the compression stroke in the housing 4.

Further, in the above-described embodiment, the control device 200 has been described as controlling the first inverter 71, the second inverter 72, the throttle motor 14, and the injector 10. However, a plurality of control devices are used to control these electric devices. You may control it. For example, the control device 200 divides the first control device that controls the first inverter 71 and the second inverter 72 and the second control device that controls the throttle motor 14 and the injector 10 into these electric devices. You may control it.

Further, in the above-described embodiment, the first piston member 24 has a set of piston pieces arranged symmetrically with respect to the rotation axis, and when the first piston member 24 is in the stopped state, the recess 24e, Although the discharge portions 42a and 42b have been described so as to supply the hydraulic oil to both of the 24f, the discharge portion is a recess of a plurality of piston pieces when the first piston member 24 has a plurality of piston pieces. Of these, at least it may be provided at a position facing the recess of the piston piece forming the combustion chamber where the fuel burns. For example, the discharge portion 42b is omitted and only the discharge portion 42a is set in the housing 4. May be good.

Even in this way, it is possible to suppress the temperature rise of the wall surface portion closer to the piston piece forming the combustion chamber where the fuel burns. Therefore, the engine can be cooled efficiently.

Further, in the above-described embodiment, the discharge portions 42a, 42b, 42c, and 42d have been described as being set as separate parts from the housing 4, but are integrally formed in, for example, the housing 4. It may be set by.

FIG. 13 is a diagram for explaining the structure of the discharge portion set in the housing in the modified example. As shown in FIG. 13, the discharge portion is set by forming the through hole so that the longitudinal angle of the through hole forming the opening 40a is the angle at which the hydraulic oil is discharged in a predetermined direction. You may.

In this way, the hydraulic oil can be discharged in a predetermined direction without providing a separate part.

Further, in the above-described embodiment, the oil pump 38 has been described as being constantly operated during the operation of the engine 2, but for example, the temperature of at least one of the first piston member 24 and the second piston member 28 has been described. The oil pump 38 may be controlled so that the discharge amount corresponds to the above.

The control device 200 may control the oil pump 38 so that the discharge amount corresponds to the temperature of at least one of the directly detected first piston member 24 and the second piston member 28, for example. Alternatively, the oil pump 38 may be controlled so that the discharge amount corresponds to the operating region of the engine 2 that correlates with the temperatures of the first piston member 24 and the second piston member 28.

Hereinafter, an example of the control process executed by the control device 200 in this modified example will be described with reference to FIG. FIG. 14 is a flowchart showing an example of the control process (No. 1) of the oil pump 38 executed by the control device 200 in the modified example. The process shown in this flowchart is called and executed from the main routine (not shown) at predetermined control cycles.

In step 100 (hereinafter, step is referred to as S) 100, the control device 200 acquires the rotation position of the first piston member 24 and the rotation position of the second piston member 28. The control device 200 acquires the rotation position of the first piston member 24 by using, for example, the rotation position (rotation angle CA1) of the first MG61. Similarly, the control device 200 acquires the rotation position of the second piston member 28 by using, for example, the rotation position (rotation angle CA2) of the second MG 62.

In S102, the control device 200 acquires the rotation speed of the first piston member 24 and the rotation speed of the second piston member 28. The control device 200 may acquire the rotation speed of the first piston member 24 by using, for example, the amount of change in the rotation position of the first piston member 24 (or the first MG61) per predetermined time immediately before. Alternatively, the control device 200 may acquire the rotation speed of the second piston member 28 by using, for example, the amount of change in the rotation position of the second piston member 28 (or the second MG 62) per predetermined time immediately before.

In S104, the control device 200 acquires the fuel supply amount. The control device 200 may acquire, for example, a command value of the fuel supply amount set according to the operating state of the engine 2 (for example, the throttle opening degree, etc.) as the fuel supply amount.

In S106, the control device 200 determines whether or not the operating region of the engine 2 is within a high temperature region where the engine 2 can reach a high temperature (the temperature of the engine 2 is higher than the threshold value). The control device 200 determines, for example, whether or not the operating region of the engine 2 is within the high temperature region by using a predetermined map.

FIG. 15 is a diagram showing a high temperature region and a low temperature region set by the rotation speed and the fuel supply amount. The vertical axis of FIG. 15 shows the fuel supply amount. The horizontal axis of FIG. 15 indicates the rotation speed of the piston member. The solid line in FIG. 15 shows the boundary between the high temperature region and the low temperature region.

As shown by the solid line in FIG. 15, the operating state of the engine 2 is set to a high temperature region where the engine 2 is required to be cooled by using the cooling device 50 by an experiment or the like, and the high temperature region and the low temperature region are defined. Boundaries are preset.

In the control device 200, the operating point of the engine 2 based on the fuel supply amount acquired in the processes of S102 and S104, the rotation speed of the first piston member 24, and the rotation speed of the second piston member 28 is closer to the boundary line. It is determined whether the operating region is in the high temperature region or the low temperature region depending on whether it is on the upper side or the lower side.

More specifically, the control device 200 has, for example, the operating point of the engine 2 on the graph shown in FIG. 15 specified by the acquired fuel supply amount and the rotation speed of the first piston member 24 (hereinafter, the first operation). When the point (described as a point) is above the boundary line shown by the solid line in FIG. 15, it is determined that the operating region of the engine 2 is within the high temperature region.

Alternatively, the control device 200 is described as, for example, an operating point of the engine 2 on the graph shown in FIG. 15 specified by the acquired fuel supply amount and the rotation speed of the second piston member 28 (hereinafter, referred to as a second operating point). ) Is above the boundary line shown by the solid line in FIG. 15, it is determined that the operating region of the engine 2 is within the high temperature region.

Further, in the control device 200, for example, when both the first operating point and the second operating point are below the boundary line shown by the solid line in FIG. 15, the operating region of the engine 2 is within the low temperature region. Is determined.

When it is determined that the operating region of the engine 2 is within the high temperature region (YES in S106), the process is transferred to S108.

At S108, the control device 200 executes discharge control. Specifically, the control device 200 discharges hydraulic oil from the discharge units 42a, 42b, 42c and 42d by operating the oil pump 38.

When it is determined that the operating region of the engine 2 is within the low temperature region (NO in S106), the process is transferred to S110.

In S110, the control device 200 does not execute the discharge control. Specifically, the control device 200 puts the oil pump 38 in a stopped state when the oil pump 38 is operating, and continues the stopped state of the oil pump 38 when the oil pump 38 is stopped. do.

In this way, during the operation of the engine 2, the rotational position of the first piston member 24 and the rotational position of the second piston member 28 are acquired (S100), and based on the amount of change in the acquired rotational position. The rotational speed of the first piston member 24 and the rotational speed of the second piston member 28 are acquired (S102), and the fuel supply amount is acquired (S104).

Therefore, when it is determined that the operating region of the engine 2 is within the high temperature region based on the acquired rotational speed of the first piston member 24, the rotational speed of the second piston member 28, and the fuel supply amount ( YES in S106), discharge control is executed (S108). On the other hand, when it is determined that the operating region of the engine 2 is within the low temperature region (NO in S106), the discharge control is not executed (S110). Therefore, the engine 2 can be efficiently cooled because the discharge amount can be controlled so as to be appropriately cooled according to the temperatures of the first piston member and the second piston member. Further, in the operating region where the temperature of the engine 2 is low, the discharge control is not executed, so that it is possible to suppress the operation of the oil pump 38 unnecessarily, so that the power consumption of the oil pump 38 is increased. It can be suppressed.

In this modification, the fuel supply amount and the rotation speed of the piston member are used to determine whether or not the temperature is in the high temperature region. For example, the temperature of the engine 2 is detected and detected by a sensor or the like. Discharge control may be executed when the temperature is higher than the threshold value, and may not be executed when the temperature is lower than the threshold value. Further, even within the same high temperature region, the discharge amount may be increased as the operating point where the temperature of the engine 2 can be higher is reached, and the discharge amount may be decreased as the temperature approaches the boundary line.

Further, in the above-described embodiment, the oil pump 38 has been described as being constantly operated during the operation of the engine 2, but for example, it depends on the rotational position of the first piston member 24 and the rotational position of the second piston member 28. The oil pump 38 may be operated intermittently.

Hereinafter, the control process executed by the control device 200 in this modification will be described with reference to FIG. FIG. 16 is a flowchart showing an example of the control process (No. 2) of the oil pump executed by the control device 200 in the modified example. The process shown in this flowchart is called and executed from the main routine (not shown) at predetermined control cycles.

In S200, the control device 200 acquires the rotation position of the first piston member 24 and the rotation position of the second piston member 28. Since the method of acquiring the rotation position is as described above, the detailed description thereof will not be repeated.

In S202, the control device 200 determines whether or not it is the timing of discharging the hydraulic oil to the first piston member 24. The control device 200 has, for example, a rotation position in which the rotation position of the first piston member 24 is located in front of the rotation position of the first piston member 24 shown in FIG. 10 by a predetermined rotation angle (counterclockwise direction). When the rotation position is within the section between the rotation position of the first piston member 24 shown in FIG. 10 and the rotation position located behind (clockwise) by a predetermined rotation angle, the first piston member 24 is reached. It is determined that it is the discharge timing of the hydraulic oil. When the rotation position of the first piston member 24 is a rotation position outside the section, the control device 200 determines that it is not the timing of discharging the hydraulic oil to the first piston member 24. In this section, for example, at least the first piston member 24 is stopped in consideration of the response delay time from the start of the hydraulic oil discharge operation to the actual discharge of the hydraulic oil from the discharge portions 42a and 42b. It is desirable that the hydraulic oil is continuously discharged from the discharge units 42a and 42b during the period of the state. When it is determined that it is the timing for discharging the hydraulic oil to the first piston member 24 (YES in S202), the process is transferred to S204.

At S204, the control device 200 executes discharge control. Since the discharge control is as described above, the detailed description thereof will not be repeated.

When it is determined that it is not the timing for discharging the hydraulic oil to the first piston member 24 (NO in S202), the process is transferred to S206.

In S206, the control device 200 determines whether or not it is the timing of discharging the hydraulic oil to the second piston member 28. In the control device 200, for example, the rotation position of the second piston member 28 is set before the rotation position of the second piston member 28 shown in FIG. 11 by a predetermined rotation angle, and the second piston member shown in FIG. 11 When the rotation position is within the section between the rotation position and the rotation position after a predetermined rotation angle from the rotation position of 28, it is determined that the hydraulic oil is discharged to the second piston member 28. When the rotation position of the second piston member 28 is a rotation position outside the section, the control device 200 determines that it is not the timing of discharging the hydraulic oil to the second piston member 28. In the section, at least the second piston member 28 is in a stopped state in consideration of the response delay time from the discharge operation of the hydraulic oil to the actual discharge of the hydraulic oil from the discharge portions 42c and 42d. It is desirable that the hydraulic oil is continuously discharged from the discharge units 42c and 42d during this period. When it is determined that it is the timing for discharging the hydraulic oil to the second piston member 28 (YES in S206), the process is transferred to S204.

If it is determined that it is not the timing to discharge the hydraulic oil to the second piston member 28 (NO in S206), the process is transferred to S208. In S208, the control device 200 does not execute the discharge control. Since the specific operation is as described above, the detailed description thereof will not be repeated.

The operation of the control device 200 based on the above-mentioned flowchart will be described with reference to FIG. FIG. 17 is a diagram for explaining control for intermittently operating the oil pump 38.

During the operation of the engine 2, the rotational position of the first piston member 24 and the rotational position of the second piston member 28 are acquired (S200). As shown in FIG. 17A, the acquired rotation position of the first piston member 24 becomes a rotation position prior to the rotation position of the first piston member 24 at the time of ignition (see the broken line frame) by a predetermined rotation angle. Occasionally (YES in S200), discharge control is executed (S204). Then, the discharge control corresponds to the case where the rotation position of the first piston member 24 becomes the rotation position corresponding to the ignition time as shown in FIG. 17 (B) or the ignition time as shown in FIG. 17 (C). It is continuously executed from the rotation position to the rotation position after a predetermined rotation angle.

On the other hand, as shown in FIG. 17D, it is not the timing of discharging the hydraulic oil to the first piston member 24 (NO in S202), nor is it the timing of discharging the hydraulic oil to the second piston member 28 (S206). NO), the discharge control is not executed (S208).

Then, as shown in FIG. 17 (E), the rotation position of the second piston member 28 becomes a rotation position prior to the rotation position of the second piston member 28 at the time of ignition (see the broken line frame) by a predetermined rotation angle. Occasionally (YES in S206), discharge control is executed (S204). Then, the discharge control is continuously executed until the rotation position of the second piston member 28 becomes the rotation position after the rotation position corresponding to the ignition time by a predetermined rotation angle.

In this way, hydraulic oil can be supplied to the recesses of the piston members that are in the stopped state of the first piston member 24 and the second piston member 28 and can reach a high temperature, so that the engine 2 can be supplied with hydraulic oil. The temperature rise can be appropriately suppressed. Further, when it is not the timing of discharging the hydraulic oil to the first piston member 24 or the timing of discharging the hydraulic oil to the second piston member 28, the discharge control is not executed, so that the oil pump 38 is unnecessary. Since it is possible to suppress the operation of the oil pump 38, it is possible to suppress an increase in power consumption in the oil pump 38.

In this modification, the discharge operation is performed by turning the oil pump 38 on and off. For example, an on-off valve that opens and closes each of the pipes 30a, 30b, 32a, and 32b in response to a control signal from the control device 200. The on-off valve may be turned on and off while the oil pump 38 is constantly operated. In this case, at the timing of discharging the hydraulic oil to the first piston member 24, the on-off valves of the pipes 30a and 30b are opened, and at the timing of discharging the hydraulic oil to the second piston member 28, the pipes 32a, The on-off valve of 32b may be opened.

Further, in the above-described embodiment, the case where the hydraulic oil is used as the cooling medium of the cooling device 50 has been described as an example, but other liquid refrigerant or gas refrigerant may be used.

Further, in the above-described embodiment, the concave portion of the first piston member 24 and the concave portion of the second piston member 28 are both described as opening in a direction parallel to the rotation axis, but are opened in a predetermined direction. Anything may be used, and the opening is not particularly limited to the one that opens in the direction parallel to the rotation axis. The recesses of the first piston member 24 and the recesses of the second piston member 28 are opened to the wall surface in the radial direction (direction toward the center of the rotation axis) in each of the first wall surface member 24b and the second wall surface member 28b, for example. It may be, or each of the first wall surface member 24b and the second wall surface member 28b may open to the wall surface in the circumferential direction (direction around the rotation axis).

The above-mentioned modification may be carried out in whole or in combination.
It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and it is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 Power generation system, 2 engine, 4 housing, 6 intake pipe, 8 exhaust pipe, 10 injector, 12 throttle valve, 14 throttle motor, 16 1st output shaft, 18 2nd output shaft, 22, 26 one-way clutch, 24 1st Piping member, 24a first rotating body, 24b first wall surface member, 24c, 24d, 24e, 24f, 28c, 28d, 28e, 28f recess, 28 second piston member, 28a second rotating body, 28b second wall surface member, 30 1st pipe, 30a, 30b, 32a, 32b pipe, 32 2nd pipe, 34 3rd pipe, 36 4th pipe, 38 oil pump, 40a, 40b, 40c, 40d opening, 42a, 42b, 42c, 42d Discharge unit, 50 cooling device, 61 1st MG, 62 2nd MG, 71 1st inverter, 72 2nd inverter, 80 battery, 90 load, 101 1st resolver, 102 2nd resolver, 200 control device.

Claims (4)

The inner peripheral surface of the housing and the first piston member include a housing, a first piston member rotatably supported in the housing, and a second piston member rotatably supported in the housing. A cooling device for a rotary piston engine in which a combustion chamber for burning fuel is formed by the second piston member and the first piston member, wherein the first piston member is a first opening in a predetermined first direction. The second piston member has a piston piece whose inside is hollow due to the provision of the recess, and the inside of the second piston member is hollow due to the provision of the second recess opened in a predetermined second direction. The engine has a stop device that stops one of the first piston member and the second piston member when fuel burns in the combustion chamber.
The cooling device is
A supply unit that supplies a cooling medium to the housing,
A discharge portion provided in the housing and discharging the cooling medium supplied to the housing to at least one of the first recess and the second recess is provided.
The discharge portion of the rotary piston type engine is provided at a position of the first recess and the second recess facing the opening of one of the recesses that is stopped when fuel is burned in the combustion chamber. Cooling system. The cooling device for a rotary piston engine according to claim 1, wherein the discharge portion faces at least a wall surface portion of the wall surface formed in the one recess, which is closer to the combustion chamber where fuel is burned. The first piston member has a plurality of piston pieces and has a plurality of piston pieces.
The discharge portion is formed in the first recess of the piston piece that forms at least the combustion chamber in which the fuel burns among the first recesses when the first piston member is stopped due to the combustion of fuel in the combustion chamber. The cooling device for a rotary piston type engine according to claim 1 or 2, which is provided at opposite positions. The cooling device further includes a discharge amount control device for controlling the discharge amount of the cooling medium from the discharge unit.
When the temperature of at least one of the first piston member and the second piston member is higher than the threshold value, the discharge amount control device produces a discharge amount more than when the temperature is lower than the threshold value. The cooling device for a rotary piston type engine according to any one of claims 1 to 3, which is increased.

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