JP3842843B2 - Internal combustion engine and gas heat pump device using the internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an internal combustion engine having a sub oil pan and a gas heat pump device using the internal combustion engine, and more particularly to a technique for forcibly circulating engine oil between a main oil pan and a sub oil pan.
[0002]
[Prior art]
In recent years, commercial refrigerators used in packaged air conditioners and the like have increasingly adopted gas heat pumps using a gas engine (hereinafter simply referred to as an engine) as an internal combustion engine as a drive source of a compressor.
[0003]
In a gas heat pump type air conditioner, a compressor of a refrigerator is driven by an engine, and air conditioning is performed by switching a four-way valve, and heat energy of engine cooling water and exhaust gas is collected and used for heating. Therefore, the engine cooling water circuit is provided with an outdoor heat exchanger or refrigerant heat exchanger that transfers thermal energy from the cooling water to the refrigerant, and an exhaust heat exchanger that transfers thermal energy from the exhaust gas to the cooling water. ing. In the gas heat pump type air conditioner, heat energy is transferred from the cooling water or the exhaust gas to the refrigerant, so that sufficient heating can be performed even in a severe winter period when the outside air temperature becomes zero degrees or less.
[0004]
By the way, an engine for a gas heat pump has a high operation rate and is often continuously operated for a long time, so that engine oil deteriorates in a short period of time as compared with an engine for an automobile or the like. Further, since the engine body is housed in the casing, access during oil change is generally not good. Therefore, in order to lengthen the interval between oil changes, in addition to the main oil pan attached to the engine body, there has been a product that increases the total oil amount by adding a relatively large capacity sub oil pan. .
[0005]
Usually, the sub oil pan and the main oil pan are communicated with each other by a communication pipe and a pressure equalizing pipe, and the engine oil moves between the two oil pans by the action of gravity. For example, when the engine is operated, the engine oil in the main oil pan is pumped to the valve system of the engine body, the bearings of each part, etc., and the oil level in the main oil pan is lowered. As a result, there is a difference in level between the oil levels of both oil pans, and the engine oil in the sub oil pan flows into the main oil pan. Immediately after the engine is stopped, engine oil drops and circulates from each part of the engine to the main oil pan, and the oil level of the main oil pan rises. As a result, there is a difference in height between the oil levels of both oil pans, and the engine oil in the main oil pan flows into the sub oil pan.
[0006]
[Problems to be solved by the invention]
By the way, in the internal combustion engine described above, the circulation of the engine oil relies only on the gravity, so that it is difficult to sufficiently secure the circulation frequency and the circulation amount, and the effect of installing the sub oil pan is not sufficiently exhibited. there were.
[0007]
For example, since the engine oil is circulated only when the engine is started and stopped, when the engine is continuously operated for a long time, the circulation frequency is very low. In view of this, the conventional apparatus employs means such as temporarily stopping the engine at a predetermined time (for example, every 24 hours) to increase the circulation frequency. However, this method is not preferable because the engine is stopped regardless of the operation request on the air conditioning side, which hinders the intended air conditioning performance.
[0008]
In the sub oil pan, engine oil in the vicinity of the communication oil pipe mainly moves between the main oil pan. For this reason, even if the capacity of the sub oil pan is increased, the amount of engine oil that is actually circulated is much less than the total oil amount, and it is difficult to greatly increase the engine oil change interval. It was.
[0009]
The present invention has been made in view of the above situation, and has realized an internal combustion engine that forcibly circulates engine oil between a main oil pan and a sub oil pan, thereby significantly increasing an engine oil replacement interval. And it aims at providing the gas heat pump apparatus using the internal combustion engine.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, in the invention according to claim 1, the main oil pan attached to the engine body and the main oil pan communicated with each other via the first communication oil passage and the first pressure equalization passage. In the internal combustion engine having a sub oil pan, a second communication oil passage communicating the main oil pan and the sub oil pan, a circulation oil pan interposed in the second communication oil passage, and the second A first check valve interposed between the sub oil pan and the circulation oil pan in the communication oil passage, and allowing the engine oil to flow only from the sub oil pan to the circulation oil pan; and the second communication A second check valve that is interposed between the circulation oil pan and the main oil pan in an oil passage and distributes engine oil only from the circulation oil pan to the main oil pan; and the circulation oil A second pressure equalizing path communicating with the first pressure equalizing path, a first valve position interposed in the second pressure equalizing path and communicating with the second pressure equalizing path, and the second pressure equalizing path. An internal combustion engine is proposed that includes a shut-off valve that can be switched between a second valve position that opens the circulation oil pan to the atmosphere at the same time as the passage is shut off, and drive control means that drives and controls the shut-off valve.
[0017]
According to the present invention, for example, when the pressure in the main oil pan becomes negative with the operation of the engine, the pressure in the sub oil pan and the circulating oil pan also becomes negative via the first and second pressure equalization paths. In this state, when the shut-off valve is switched from the first valve position to the second valve position by the drive control means, the engine oil in the circulating oil pan flows into the main oil pan due to the differential pressure between the atmospheric pressure and the negative pressure. . At this time, the operation of the first check valve prevents the engine oil from flowing from the circulation oil pan to the sub oil pan. When the oil level of the main oil pan rises, there is a difference in level between the oil levels, and engine oil circulates from the main oil pan to the sub oil pan. When the shutoff valve is switched from the second valve position to the first valve position, there is no pressure difference between the oil pans, and engine oil flows from the sub oil pan to the circulation oil pan. At this time, the operation of the second check valve prevents the engine oil from flowing from the main oil pan to the circulating oil pan.
[0018]
According to a second aspect of the present invention, there is provided an internal combustion engine having a main oil pan attached to the engine body, and a sub oil pan connected to the main oil pan through a first communication oil passage and a first pressure equalization passage. In the engine, a second communication oil passage communicating the main oil pan and the sub oil pan, a circulation oil pan interposed in the second communication oil passage, and the main oil of the second communication oil passage A first check valve that is interposed between the pan and the circulation oil pan and distributes engine oil only from the main oil pan to the circulation oil pan; and the circulation oil in the second communication oil passage A second check valve which is interposed between the pan and the sub oil pan and allows the engine oil to flow only from the circulation oil pan to the sub oil pan; the circulation oil pan and the first pressure equalizing path And A second pressure equalizing path that is passed through, a first valve position that is interposed in the second pressure equalizing path, and that communicates with the second pressure equalizing path; An internal combustion engine including a shut-off valve that can be switched between a second valve position that opens the air to the atmosphere and a drive control means that drives and controls the shut-off valve is proposed.
[0019]
According to the present invention, for example, when the pressure in the main oil pan becomes negative with the operation of the engine, the pressure in the sub oil pan and the circulating oil pan also becomes negative via the first and second pressure equalization paths. In this state, when the shut-off valve is switched from the first valve position to the second valve position by the drive control means, the engine oil in the circulating oil pan flows into the sub oil pan due to the differential pressure between the atmospheric pressure and the negative pressure. . At this time, the flow of engine oil from the circulating oil pan to the main oil pan is prevented by the action of the first check valve. When the oil level of the sub oil pan rises, a difference in level occurs between the oil levels, and the engine oil circulates from the sub oil pan to the main oil pan. When the shut-off valve is switched from the second valve position to the first valve position, there is no pressure difference between the oil pans, and engine oil flows from the main oil pan to the circulating oil pan. At this time, the operation of the second check valve prevents the engine oil from flowing from the sub oil pan to the circulating oil pan.
[0020]
According to a third aspect of the present invention, there is provided an internal combustion engine having a main oil pan attached to the engine body, and a sub oil pan connected to the main oil pan through a first communication oil passage and a first pressure equalization passage. In the engine, a second communication oil passage communicating the main oil pan and the sub oil pan, a circulation oil pan interposed in the second communication oil passage, and the sub oil in the second communication oil passage A first check valve that is interposed between the pan and the circulation oil pan and distributes engine oil only from the sub oil pan to the circulation oil pan; and the circulation oil in the second communication oil passage Interposed between the pan and the main oil pan,
A second check valve that allows engine oil to flow only from the circulation oil pan to the main oil pan; a second pressure equalization path that communicates the circulation oil pan and the first pressure equalization path; Switching between a first valve position, which is interposed in the pressure path and communicates with the second pressure equalization path, and a second valve position which blocks the second pressure equalization path and simultaneously opens the circulating oil pan to the atmosphere. And a drive control means for driving and controlling the shut-off valve. The drive control means moves the shut-off valve from the first valve position to the second valve position for a second predetermined time every first predetermined time. An internal combustion engine to be switched is proposed.
[0021]
According to the present invention, for example, when the pressure in the main oil pan becomes negative with the operation of the engine, the pressure in the sub oil pan and the circulating oil pan also becomes negative via the first and second pressure equalization paths. In this state, when the shutoff valve is switched from the first valve position to the second valve position by the drive control means every first predetermined time (for example, 24 hours), the pressure for circulation is determined by the differential pressure between the atmospheric pressure and the negative pressure. Engine oil in the oil pan flows into the main oil pan. At this time, the operation of the first check valve prevents the engine oil from flowing from the circulation oil pan to the sub oil pan. When the oil level of the main oil pan rises, there is a difference in level between the oil levels, and engine oil circulates from the main oil pan to the sub oil pan. Further, when the shut-off valve is switched from the second valve position to the first valve position after the elapse of the second predetermined time (for example, 10 minutes), the pressure difference between the oil pans disappears, and the circulation oil pan is changed from the sub oil pan. Engine oil flows into the. At this time, the operation of the second check valve prevents the engine oil from flowing from the main oil pan to the circulating oil pan.
[0022]
According to a fourth aspect of the present invention, there is provided an internal combustion engine having a main oil pan attached to the engine body and a sub oil pan communicated with the main oil pan through a first communication oil passage and a first pressure equalization passage. In the engine, a second communication oil passage communicating the main oil pan and the sub oil pan, a circulation oil pan interposed in the second communication oil passage, and the main oil of the second communication oil passage A first check valve that is interposed between the pan and the circulation oil pan and distributes engine oil only from the main oil pan to the circulation oil pan; and the circulation oil in the second communication oil passage A second check valve which is interposed between the pan and the sub oil pan and allows the engine oil to flow only from the circulation oil pan to the sub oil pan; the circulation oil pan and the first pressure equalizing path And A second pressure equalizing path that is passed through, a first valve position that is interposed in the second pressure equalizing path, and that communicates with the second pressure equalizing path; And a drive control means for driving and controlling the shut-off valve, and the drive control means sets the shut-off valve to the first valve every first predetermined time. An internal combustion engine for switching from a position to a second valve position over a second predetermined time is proposed.
[0023]
According to the present invention, for example, when the pressure in the main oil pan becomes negative with the operation of the engine, the pressure in the sub oil pan and the circulating oil pan also becomes negative via the first and second pressure equalization paths. In this state, when the shutoff valve is switched from the first valve position to the second valve position by the drive control means every first predetermined time (for example, 24 hours), the pressure for circulation is determined by the differential pressure between the atmospheric pressure and the negative pressure. Engine oil in the oil pan flows into the sub oil pan. At this time, the flow of engine oil from the circulating oil pan to the main oil pan is prevented by the action of the first check valve. When the oil level of the sub oil pan rises, a difference in level occurs between the oil levels, and the engine oil circulates from the sub oil pan to the main oil pan. Further, when the shut-off valve is switched from the second valve position to the first valve position after the second predetermined time (for example, 10 minutes) has elapsed, there is no pressure difference between the oil pans, and the main oil pan and the circulating oil pan are removed. Engine oil flows into the. At this time, the operation of the second check valve prevents the engine oil from flowing from the sub oil pan to the circulating oil pan.
[0024]
The invention of claim 5 proposes a gas heat pump device using the internal combustion engine of claims 1 to 4 as a drive source of a compressor.
[0025]
According to the present invention, since the total amount of engine oil stored in all the oil pans can be used for engine lubrication, cooling, and the like, deterioration of the engine oil is prevented over a long period of time, and the gas heat pump It is possible to reliably extend the maintenance interval of the apparatus.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, two embodiments of the present invention will be described in detail with reference to the drawings.
[0027]
FIG. 1 is a schematic configuration diagram of a gas heat pump type air conditioner, in which a refrigerant circuit is indicated by a thick dashed line and a cooling water circuit is indicated by a thick solid line. The air conditioner is composed of an indoor unit 1 and an outdoor unit 3, and an indoor heat exchanger 7 provided with a flow divider 5 and a fan 9 are installed on the indoor unit 1 side. Further, on the outdoor unit 3 side, as an element part of the refrigerant circuit, there are a compressor 11, an electromagnetic four-way valve 13, a refrigerant heat exchanger 15, an outdoor heat exchanger 19 provided with a flow divider 17, a fan 21, and the like. The engine 31, the exhaust heat exchanger 33, the thermostat 35, the electric three-way valve 37, the electric cooling water pump 39 and the like are installed as component parts of the cooling water circuit. In the figure, 43 is an exhaust pipe connected to the exhaust heat exchanger 33, 47 is a fan motor for driving the fan 21, and 49 is a flexible coupling for connecting the engine 31 and the compressor 11.
[0028]
Inside the outdoor unit 3, a control unit 61 that drives and controls the four-way valve 13, the electric three-way valve 37, the fan motor 47, and the like is installed. The control unit 61 includes a CPU, an input / output interface, a ROM, a RAM, a timer counter, and the like. The input interface includes a water temperature provided in a cooling water pipe 87 between the engine 31 and the thermostat 35. A sensor 63, a heat exchange temperature sensor 65 attached to the outdoor heat exchanger 19, an exhaust temperature sensor 67 provided in the exhaust pipe 43, an outdoor temperature sensor 69 attached to the outer wall surface, and the like are connected. The control unit 61 is connected to a control unit (not shown) on the indoor unit 1 side, and exchanges signals with each other.
[0029]
Next, the flow of refrigerant and cooling water during heating operation will be described.
[0030]
The liquid refrigerant that flows into the outdoor unit 3 from the refrigerant pipe 71 flows into the refrigerant heat exchanger 15 via the flow divider 17, the outdoor heat exchanger 19, the refrigerant pipe 75, the four-way valve 13, and the refrigerant pipe 77. Heat is passed while passing through the heat exchangers 19 and 15. The refrigerant heat exchanger 15 employs a double pipe type in which cooling water passes around the refrigerant pipe. In the outdoor heat exchanger 19, the refrigerant pipe and the cooling water pipe are connected via plate fins. Plate fin type is adopted. The gas refrigerant heated by the heat exchangers 19 and 15 flows into the compressor 11 via the refrigerant pipe 78 and is further heated by being compressed here. The high-temperature gas refrigerant discharged from the compressor 11 flows into the indoor heat exchanger 7 on the indoor unit 1 side via the refrigerant pipe 79, the four-way valve 13, and the refrigerant pipe 81 and is blown by the fan 9. After the heat energy is released and heated, it becomes liquid refrigerant and flows again from the refrigerant pipe 71 to the outdoor unit 3 side.
[0031]
On the other hand, the cooling water discharged from the cooling water pump 39 flows into the exhaust heat exchanger 33 via the cooling water pipe 85, is heated by the exhaust gas, and then flows into the engine 31. Cooling water that has become hot due to cooling of the engine 31 flows into the outdoor heat exchanger 19 via the cooling water pipe 87, the thermostat 35, and the cooling water pipe 89, and releases thermal energy. The cooling water that has released the heat energy in the outdoor heat exchanger 19 is circulated again to the cooling water pump 39 via the cooling water pipe 91, the electric three-way valve 37, and the cooling water pipe 93.
[0032]
At this time, when the electric three-way valve 37 is switched by the control unit 61, the cooling water flows into the refrigerant heat exchanger 15 via the cooling water pipe 95, where the cooling water pipe is discharged after releasing the heat energy. 97 circulates to the cooling water pump 39 via the cooling water pipe 93. Further, until the cooling water temperature at the outlet of the engine 31 reaches the lower limit set value (60 ° C. in the embodiment), the cooling water does not flow to the outdoor heat exchanger 19 side, and the whole amount passes from the thermostat 35 via the bypass pipe 99. And recirculates to the cooling water pump 39. When the cooling water temperature is between the lower limit setting value and the upper limit setting value (70 ° C. in the embodiment), the cooling water flows from the thermostat 35 to both the bypass pipe 99 and the cooling water pipe 89, and the cooling water temperature is set to the upper limit. When the value is exceeded, the entire amount flows into the cooling water pipe 89.
[0033]
FIG. 2 shows a schematic configuration around the engine according to the first embodiment. The engine 31 of the present embodiment is obtained by modifying a fuel system of a gasoline engine for a passenger car for natural gas. A cylinder head 103 containing a valve mechanism (not shown) is placed on the cylinder block 101. An oil pan (hereinafter referred to as a main oil pan) 105 is attached to the bottom of the cylinder block 101. The main oil pan 105 for passenger cars is used as it is, and has a relatively small capacity (3.9 liters in this embodiment). In the figure, reference numeral 107 denotes an oil strainer, which is connected to an oil pump (not shown) in the cylinder block 101.
[0034]
An intake manifold 113 in which a surge tank is integrated is attached to the cylinder head 103. The flow rate of the outside air introduced from the air cleaner 115 is controlled by an electric throttle valve 117 and is sucked into a combustion chamber (not shown) of each cylinder through the intake manifold 113 under a negative pressure. An oil separator 123 is disposed on the upper portion of the cam cover 121, and captures oil mist in blow-by gas generated in the engine 31 and circulates it to the main oil pan 105 or the sub oil pan 131 as engine oil. The oil separator 123 communicates with the upstream of the throttle valve 117 via the blow-by hose 125, and the blow-by gas from which the oil mist has been removed is sucked into the intake manifold 113 side together with the outside air.
[0035]
The engine 31 is provided with a sub oil pan 131 and a circulation oil pan 133. The sub oil pan 131 communicates with the lower part of the main oil pan 105 via the first communication oil pipe 135 at the lower part, and the upper space is located above the main oil pan 105 via the first pressure equalizing pipe 137 and the cylinder block 101. It communicates with space. The sub oil pan 131 is set to have a relatively large capacity (211.1 liters in this embodiment).
[0036]
On the other hand, the lower part of the circulation oil pan 133 communicates with the main oil pan 105 and the sub oil pan 131 via two second communication oil pipes 141 and 143. A first check valve 145 that allows engine oil to flow only from the sub oil pan 131 side to the circulation oil pan 133 side is interposed in the pipe line of the second communication oil pipe 141. A second check valve 147 that allows engine oil to flow only from the circulation oil pan 133 side to the main oil pan 105 side is interposed in the conduit of the second communication oil pipe 143. In the present embodiment, the first communication oil pipe 135 and the second communication oil pipes 141 and 143 are connected to the main oil pan 105 and the sub oil pan 131 at portions separated from each other. The circulation oil pan 135 is set to a relatively small capacity (3 liters).
[0037]
The upper space of the circulation oil pan 133 is communicated with the first pressure equalizing pipe 137 via the second pressure equalizing pipe 151 and is also provided by a three-way electromagnetic valve 153 interposed in the conduit of the second pressure equalizing pipe 151. It is also open to the atmosphere. The three-way solenoid valve 153 is a known one, and the upper space of the circulation oil pan 133 is communicated with the first pressure equalizing pipe 137 in a demagnetized state, and the upper space of the circulation oil pan 133 is excited in the excited state. It is configured to open to the atmosphere.
[0038]
In the outdoor unit 3, an electronic control unit (ECU) 161 including a CPU, an input / output interface, a ROM, a RAM, a timer, and the like is installed. Based on information from a control program and sensors, a throttle valve 117 and a three-way electromagnetic Centralized control of each device in the outdoor unit 3 including the valve 153 is performed.
[0039]
The operation of the first embodiment will be described below.
[0040]
When the operation of the air conditioner is started, the engine 31 is started by a command from the ECU 161, and the compressor 11 is driven via the flexible coupling 49. Thereby, the refrigerant circulates in the refrigerant circuit, and the heating operation is performed according to the procedure described above, or the cooling operation is performed by switching the four-way valve 13. At this time, in the engine 31, the engine oil 121 in the main oil pan 105 is pumped to each part, and is used for lubrication and cooling of the valve operating mechanism and each sliding part. Then, the cooling water discharged from the cooling water pump 39 circulates through the cooling water circuit from the cylinder block 101 via the cylinder head 103.
[0041]
On the other hand, when the engine 31 is started, the engine oil 121 in the main oil pan 105 is sucked into the oil pump through the oil strainer 107, and the oil level in the main oil pan 105 is lowered. Therefore, an oil level difference temporarily occurs between the main oil pan 105 and the sub oil pan 131. However, since the upper space of both the oil pans 105 and 131 is communicated by the first pressure equalizing pipe 137, the engine oil flows from the sub oil pan 131 into the main oil pan 105, and the oil level difference is gradually eliminated. Is done. Further, during normal operation, since the second pressure equalizing pipe 151 communicates with the first pressure equalizing pipe 137, the oil level of the circulating oil pan 133 is also equal to the oil level of both the oil pans 105 and 131.
[0042]
Further, when the intake negative pressure increases as the engine speed increases, the inside of the main oil pan 105 is gradually evacuated through the blow-by hose 125, the oil separator 123, and the like. In this embodiment, since the upper space communicates with each other via the first and second pressure equalizing pipes 137 and 151, the inside of each oil pan 105, 131, 133 gradually becomes negative pressure (the engine speed is 2,200). rpm, about -80 mmHg).
[0043]
Now, after starting the engine 1, the ECU 161 starts exciting the three-way solenoid valve 153 every first predetermined time (24 hours in this embodiment) based on the output signal of the built-in timer. Then, as described above, since the upper space of the circulation oil pan 133 is opened to the atmosphere, the pressure (atmospheric pressure) in the circulation oil pan 133 becomes larger than the pressure (negative pressure) in the main oil pan 105. .
[0044]
As a result, the engine oil in the circulation oil pan 133 flows into the main oil pan 105 via the second communication oil pipe 143 as shown by the solid line arrow in FIG. At this time, the engine oil does not flow from the circulation oil pan 133 to the sub oil pan 131 by the action of the first check valve 145. In addition, engine oil flows from the main oil pan 105 into the sub oil pan 131 in order to eliminate the difference in oil level caused by this. In this embodiment, since the capacity of the circulation oil pan 135 is set to be relatively small, immediately after the engine oil flows into the main oil pan 105 from the circulation oil pan 133, Overflow does not occur.
[0045]
The ECU 161 demagnetizes the three-way solenoid valve 153 when a second predetermined time (10 minutes in the present embodiment) elapses after excitation. Then, as described above, since the upper space of the circulation oil pan 133 is communicated with the first pressure equalizing pipe 137, there is no pressure difference between the oil pans 105, 131, and 133.
[0046]
As a result, the engine oil flows from the sub oil pan 131 into the circulating oil pan 133 whose oil level has been lowered by the outflow of the engine oil, as indicated by the dashed arrows in FIG. At this time, the operation of the second check valve 147 does not cause the engine oil to flow from the main oil pan 105 to the circulating oil pan 133.
[0047]
As described above, in the first embodiment of the present invention, the engine oil flows back to the circulation oil pan 133 via the circulation oil pan 133 → the main oil pan 105 → the sub oil pan 131. Engine oil circulates between the main oil pans 105 without any stagnation. In addition, since the first communication oil pipe 135 and the second communication oil pipes 141 and 143 are connected to the main oil pan 105 and the sub oil pan 131 at portions separated from each other, The engine oil is well stirred in
[0048]
FIG. 3 shows a schematic configuration around the engine according to the second embodiment. The configuration of this embodiment is substantially the same as that of the first embodiment described above, but differs in the following points. In other words, the first check valve 145 is interposed in the pipe line of the second communication oil pipe 143, and, contrary to the first embodiment, only the engine from the main oil pan 105 side to the circulation oil pan 133 side is engine. Distribute the oil. Further, a second check valve 147 is interposed in the pipe line of the second communication oil pipe 141, which is also opposite to the first embodiment, from the circulation oil pan 133 side to the sub oil pan 131 side. Only distribute engine oil.
[0049]
Hereinafter, the operation of the second embodiment will be described.
[0050]
Also in the present embodiment, the ECU 161 starts exciting the three-way solenoid valve 153 every first predetermined time (24 hours in the present embodiment). Then, the upper space of the circulation oil pan 133 is opened to the atmosphere, and the pressure (atmospheric pressure) in the circulation oil pan 133 becomes larger than the pressure (negative pressure) in the sub oil pan 131.
[0051]
As a result, the engine oil in the circulation oil pan 133 flows into the sub oil pan 131 via the second communication oil pipe 141 as indicated by the solid arrow in FIG. At this time, the engine oil does not flow from the circulation oil pan 133 to the main oil pan 105 due to the action of the first check valve 145. Further, engine oil flows from the sub oil pan 131 into the main oil pan 105 in order to eliminate the oil level difference caused by this.
[0052]
The ECU 161 demagnetizes the three-way solenoid valve 153 when a second predetermined time (10 minutes in the present embodiment) elapses after excitation. Then, as described above, since the upper space of the circulation oil pan 133 is communicated with the first pressure equalizing pipe 137, there is no pressure difference between the oil pans 105, 131, and 133.
[0053]
As a result, the engine oil flows from the main oil pan 105 into the circulating oil pan 133 whose oil level has been lowered by the outflow of the engine oil, as indicated by the dashed arrows in FIG. At this time, due to the action of the second check valve 147, engine oil does not flow from the sub oil pan 131 to the circulation oil pan 133.
[0054]
As described above, in the second embodiment of the present invention, contrary to the first embodiment, the engine oil passes through the circulation oil pan 133 → the sub oil pan 131 → the main oil pan 105 to the circulation oil pan 133. The engine oil circulates between the sub oil pan 131 and the main oil pan 105 without any stagnation. In addition, since the first communication oil pipe 135 and the second communication oil pipes 141 and 143 are connected to the main oil pan 105 and the sub oil pan 131 at portions separated from each other, similarly to the first embodiment. Further, the stirring of the engine oil in both oil pans 105 and 131 is also good.
[0055]
As described above, in both the above-described embodiments, the engine is interposed between the main oil pan 105 and the sub oil pan 131 using only the negative pressure and the atmospheric pressure by driving and controlling the three-way solenoid valve 151. Oil can be circulated. As a result, the entire amount of engine oil can be used for lubrication and cooling of the engine 31 without using an expensive circulation pump or the like, and it is possible to prevent deterioration of the engine oil, lengthen the replacement interval, or the like. It became so.
[0056]
The description of the specific embodiment is finished above, but the present invention is not limited to the above-described embodiment. For example, instead of the circulation oil pan or the check valve, an electric oil pump or the like may be interposed in the second circulation oil passage and may be driven intermittently or continuously. In addition, the specific configuration of other parts can be changed as appropriate without departing from the spirit of the present invention. Furthermore, although the said embodiment is related with the internal combustion engine for air conditioners, it is suitable also for an internal combustion engine for power generation etc. which has a sub oil pan.
[0057]
【The invention's effect】
As described above, according to the internal combustion engine of the present invention, the engine oil is forcibly circulated between the main oil pan and the sub oil pan. Therefore, the entire amount of engine oil is used for engine lubrication and cooling. As a result, the engine oil can be prevented from deteriorating and the replacement interval can be extended. In addition, if the engine oil is circulated by inserting a circulation oil pan and a check valve in the second circulation oil passage and introducing air into the circulation oil pan, the equipment cost and running cost can be reduced. Is possible. Further, according to the gas heat pump device using this internal combustion engine, it is possible to reliably extend the maintenance interval.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an air conditioner according to an embodiment of the present invention.
FIG. 2 is a schematic configuration diagram around an engine according to the first embodiment.
FIG. 3 is a schematic configuration diagram around an engine according to a second embodiment.
[Explanation of symbols]
1 Outdoor unit
3 Indoor units
31 engine
105 Main oil pan
131 Sub oil pan
133 Oil pan for circulation
135 1st communication oil pipe
137 First pressure equalizing pipe
141,143 Second communication oil pipe
145 First check valve
147 Second check valve
151 2nd pressure equalizing pipe
153 Three-way solenoid valve
161 Electronic control unit

Claims (5)

An internal combustion engine having a main oil pan attached to an engine body and a sub oil pan connected to the main oil pan through a first communication oil passage and a first pressure equalization passage, the main oil pan, A second communication oil passage communicating with the sub oil pan, a circulation oil pan interposed in the second communication oil passage, and the sub oil pan and the circulation oil pan in the second communication oil passage. Interposed between the first check valve for circulating engine oil only from the sub oil pan to the circulation oil pan, and between the circulation oil pan and the main oil pan in the second communication oil passage. And a second check valve that allows the engine oil to flow only from the circulation oil pan to the main oil pan, and a second pressure equalization path that communicates the circulation oil pan and the first pressure equalization path. And this Between a first valve position that is interposed in the two pressure equalization paths and communicates with the second pressure equalization path, and a second valve position that blocks the second pressure equalization path and simultaneously opens the circulating oil pan to the atmosphere. An internal combustion engine comprising: a shut-off valve that can be switched in step 1; and drive control means for driving and controlling the shut-off valve. An internal combustion engine having a main oil pan attached to an engine body and a sub oil pan connected to the main oil pan through a first communication oil passage and a first pressure equalization passage, the main oil pan, A second communication oil passage communicating with the sub oil pan; a circulation oil pan interposed in the second communication oil passage; and the main oil pan and the circulation oil pan in the second communication oil passage. A first check valve interposed between the main oil pan and the circulation oil pan, and between the circulation oil pan and the sub oil pan in the second communication oil passage. And a second check valve that allows the engine oil to flow only from the circulation oil pan to the sub oil pan, and a second pressure equalization path that communicates the circulation oil pan and the first pressure equalization path. And this Between a first valve position that is interposed in the two pressure equalization paths and communicates with the second pressure equalization path, and a second valve position that blocks the second pressure equalization path and simultaneously opens the circulating oil pan to the atmosphere. An internal combustion engine comprising: a shut-off valve that can be switched in step 1; and drive control means that drives and controls the shut-off valve. An internal combustion engine having a main oil pan attached to an engine body and a sub oil pan connected to the main oil pan through a first communication oil passage and a first pressure equalization passage, the main oil pan, A second communication oil passage communicating with the sub oil pan, a circulation oil pan interposed in the second communication oil passage, and the sub oil pan and the circulation oil pan in the second communication oil passage. Interposed between the first check valve for circulating engine oil only from the sub oil pan to the circulation oil pan, and between the circulation oil pan and the main oil pan in the second communication oil passage. And a second check valve that allows the engine oil to flow only from the circulation oil pan to the main oil pan, and a second pressure equalization path that communicates the circulation oil pan and the first pressure equalization path. And this Between a first valve position that is interposed in the two pressure equalization paths and communicates with the second pressure equalization path, and a second valve position that blocks the second pressure equalization path and simultaneously opens the circulating oil pan to the atmosphere. And a drive control means for driving and controlling the shut-off valve. The drive control means moves the shut-off valve from the first valve position to the second valve position for a second predetermined time every first predetermined time. An internal combustion engine characterized by switching over the range. An internal combustion engine having a main oil pan attached to an engine body and a sub oil pan connected to the main oil pan through a first communication oil passage and a first pressure equalization passage, the main oil pan, A second communication oil passage communicating with the sub oil pan; a circulation oil pan interposed in the second communication oil passage; and the main oil pan and the circulation oil pan in the second communication oil passage. A first check valve interposed between the main oil pan and the circulation oil pan, and between the circulation oil pan and the sub oil pan in the second communication oil passage. And a second check valve that allows the engine oil to flow only from the circulation oil pan to the sub oil pan, and a second pressure equalization path that communicates the circulation oil pan and the first pressure equalization path. And this Between a first valve position that is interposed in the two pressure equalization paths and communicates with the second pressure equalization path, and a second valve position that blocks the second pressure equalization path and simultaneously opens the circulating oil pan to the atmosphere. And a drive control means for driving and controlling the shut-off valve. The drive control means moves the shut-off valve from the first valve position to the second valve position for a second predetermined time every first predetermined time. An internal combustion engine characterized by switching over the range. Gas heat pump device being characterized in that the drive source of the compressor internal combustion engine according to claim 1-4.

Images