Engine equipment

Abstract

To inhibit an oil from being heated to a high temperature in an engine device which performs oil jetting in which the oil is jetted to a piston of an engine.SOLUTION: An engine device includes: an engine; an oil jet mechanism which jets an oil for lubricating the engine to a piston; and a control device which controls the engine. The control device significantly limits an engine load when a temperature of the oil lubricating the engine is high compared to when the temperature of the oil is low. The action inhibits the oil from being heated to a high temperature and prevents a trouble that an oil pressure is decreased by the oil being heated to the high temperature to hinder oil jetting, in which the oil is jetted to the piston to cool the piston, from being performed effectively.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an engine device. [Background technology]

[0002] Conventionally, as an engine device of this type, one that uses an oil jet to inject oil that lubricates the engine onto the inside of the piston has been proposed (see, for example, Patent Document 1). In this engine device, the oil pressure value is adjusted so that it becomes smaller as the oil temperature increases, thereby preventing the oil from atomizing in the oil jet while preventing any impediment to the supply of oil to each part of the engine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-280559 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned engine device, when the oil becomes hot, the viscosity of the oil decreases, and there is a concern that even if an oil jet is used, the oil will not reach the piston and the piston will not be cooled.

[0005] The main object of the engine device of the present invention is to prevent the oil from becoming too hot in an engine device that uses an oil jet to inject oil onto a piston of the engine. [Means for solving the problem]

[0006] In order to achieve the above-mentioned main object, the engine device of the present invention employs the following means.

[0007] The engine device of the present invention comprises: The engine, an oil injection mechanism that injects oil to lubricate the engine onto a piston; A control device for controlling the engine; An engine device comprising: The control device limits the engine load to a greater extent when the oil temperature is high than when the oil temperature is low. It is characterized by:

[0008] In the engine device of the present invention, when the oil temperature is high, the engine load is largely limited compared to when the oil temperature is low. This makes it possible to prevent the oil from becoming too hot, and to prevent the inconvenience of the oil not reaching the piston even when an oil jet is performed due to the oil becoming too hot (the inconvenience of not being able to cool the piston).

[0009] In the engine system of the present invention, the control device may set a load upper limit value according to the oil temperature and limit the engine load so that the engine load is guarded at the load upper limit value. In this way, the engine load can be set to be equal to or lower than the load upper limit value according to the oil temperature, and the engine load can be limited according to the oil temperature.

[0010] In the engine device of the present invention, the control device may perform the restriction based on the oil temperature in the low rotation range of the engine. The oil pump used for the oil jet often functions according to the rotation of the crankshaft of the engine. In this case, the oil pressure is low in the low rotation range of the engine, so that the oil does not reach the piston even if the oil jet is performed in the low rotation range of the engine. Therefore, by limiting the engine load in the low rotation range of the engine, it is possible to prevent the oil from becoming hot in the low rotation range of the engine, and to prevent the inconvenience that the oil does not reach the piston even if the oil jet is performed. Note that in the high rotation range of the engine, the oil pump is functioning sufficiently, so that the oil pressure is high and the oil reaches the piston by the oil jet even if the oil becomes hot. [Brief description of the drawings]

[0011] [Figure 1] 1 is a diagram showing an outline of the configuration of an engine device 10. FIG. [Diagram 2] 4 is an explanatory diagram showing an example of input / output signals of an electronic control unit 70. FIG. [Diagram 3] 13 is a flowchart showing an example of an engine load limiting process for an oil jet executed by an electronic control unit 70. [Figure 4] FIG. 4 is an explanatory diagram showing an example of a load upper limit value setting map; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Next, a mode for carrying out the present invention will be described using examples. EXAMPLES

[0013] Fig. 1 is a schematic diagram showing the configuration of an engine device 10 according to an embodiment of the present invention, and Fig. 2 is an explanatory diagram showing an example of input / output signals of an electronic control unit 70. The engine device 10 according to the embodiment is mounted on a general vehicle that runs using power from an engine 12, or on various hybrid vehicles that are equipped with a motor in addition to the engine 12, and includes the engine 12, a turbocharger 40, a fuel supply device 16, and an electronic control unit 70, as shown in Figs. 1 and 2.

[0014] The engine 12 is configured as an internal combustion engine that outputs power using fuel such as gasoline or diesel supplied from a fuel tank 11. The engine 12 has a port injection valve 28 that injects fuel into an intake port, an in-cylinder injection valve 29 that injects fuel into a combustion chamber 31, and an ignition plug 32. The in-cylinder injection valve 29 is disposed approximately in the center of the top of the combustion chamber 31, and injects fuel in a spray form. The ignition plug 32 is disposed near the in-cylinder injection valve 29 so as to be able to ignite the fuel sprayed in a spray form from the in-cylinder injection valve 29.

[0015] The engine 12 is capable of operating in any one of a port injection mode, a direct injection mode, and a combined injection mode by having a port injection valve 28 and a direct injection valve 29. In the embodiment, the ratio of the fuel injection amount by the port injection valve 28 to the total fuel injection amount is defined as a port injection ratio Rp (0 ≦ Rp ≦ 1). The port injection mode is the case where the port injection ratio Rp has a value of 1, the direct injection mode is the case where the port injection ratio Rp has a value of 0, and in the combined injection mode, the port injection ratio Rp is greater than 0 and less than 1 (0 < Rp < 1).

[0016] In the port injection mode, air cleaned by the air cleaner 22 is inhaled into the intake pipe 23 and passed through the intercooler 25, throttle valve 26, and surge tank 27 in this order. Fuel is injected from the port injection valve 28 on the downstream side of the surge tank 27 in the intake pipe 23, and the air and fuel are mixed. This air-fuel mixture is inhaled into the combustion chamber 31 through the intake valve 30 and explosively combusted by an electric spark from the spark plug 32. Then, the reciprocating motion of the piston 33 pushed down by the energy of the explosive combustion is converted into the rotational motion of the crankshaft 14. In the direct injection mode, air is inhaled into the combustion chamber 31 in the same manner as in the port injection mode, and fuel is injected one or more times from the direct injection valve 29 during the intake stroke, compression stroke, or expansion stroke, and explosively combusted by an electric spark from the spark plug 32 to obtain the rotational motion of the crankshaft 14. Particularly when fuel is injected during the expansion stroke, the fuel injection from the direct injection valve 29 and the ignition by the spark plug 32 are synchronized during the expansion stroke so that the spray-like fuel injected from the direct injection valve 29 can be ignited. In the combined injection mode, fuel is injected from the port injection valve 28 when air is inhaled into the combustion chamber 31, and fuel is injected one or more times from the direct injection valve 29 during the intake stroke, compression stroke, or expansion stroke, and explosively combusted by an electric spark from the spark plug 32 to obtain the rotational motion of the crankshaft 14.

[0017] Exhaust discharged from the combustion chamber 31 to the exhaust pipe 35 via the exhaust valve 34 is discharged into the outside air via a purification device 37 having a catalyst (three-way catalyst) that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). A starter (not shown) that cranks the engine 12 and an alternator 48 that generates electricity using the power of the engine 12 are attached to the crankshaft 14. The alternator 48 supplies the generated electricity to a power line that supplies power from a battery (not shown) to a fan motor 38d, a water pump 38e, and the like of the engine cooling system 38.

[0018] The fuel supply device 16 includes a fuel tank 11, a feed pump 11p, a low-pressure supply pipe 17, a high-pressure pump 18, and a high-pressure supply pipe 19. Fuel from the fuel tank 11 is pumped by the feed pump 11p and supplied to the port injection valve 28 via the low-pressure supply pipe 17. The feed pump 11p is configured as an electric pump that operates by receiving power from a battery (not shown), and is disposed in the fuel tank 11. Although not shown, the low-pressure supply pipe 17 is also provided with a check valve that allows fuel to flow in the direction from the feed pump 11p side to the port injection valve 28 side and regulates fuel flow in the opposite direction. In addition, the fuel from the low-pressure supply pipe 17 is pumped by the high-pressure pump 18 and supplied to the in-cylinder injection valve 29 via the high-pressure supply pipe 19. The high-pressure pump 18 is configured as a pump driven by power from the engine 12 (in the embodiment, the rotation of the intake camshaft that opens and closes the intake valve 30). The high-pressure pump 18 has an electromagnetic valve 18a connected to its intake port which opens and closes when pressurizing the fuel, a check valve 18b connected to its discharge port which regulates the backflow of fuel and maintains the fuel pressure in the high-pressure supply pipe 19, and a plunger 18c which operates by the rotation (rotation of the intake camshaft) of the engine 12. When the electromagnetic valve 18a is opened while the engine 12 is running, the high-pressure pump 18 sucks in fuel from the low-pressure supply pipe 17, and when the electromagnetic valve 18a is closed, the fuel compressed by the plunger 18c is intermittently sent to the high-pressure supply pipe 19 via the check valve 18b, thereby pressurizing the fuel to be supplied to the high-pressure supply pipe 19. Note that when the high-pressure pump 18 is driven, the fuel pressure in the low-pressure supply pipe 17 and the fuel pressure (fuel pressure) in the high-pressure supply pipe 19 pulsate in response to the rotation of the engine 12 (rotation of the intake camshaft).

[0019] The engine 12 is provided with an engine cooling system 38 that cools the engine 12 with a heat exchange medium (cooling water, etc.). The engine cooling system 38 includes a circulation flow path 38a that circulates the heat exchange medium between a water jacket (not shown) of the engine 12 and a radiator 38b. A fan 38c driven by a fan motor 38d is attached to the radiator 38b, and the internal heat exchange medium (water, etc.) is cooled by outside air. A water pump 38e that circulates the heat exchange medium is attached to the circulation flow path 38a.

[0020] The supercharger 40 is configured as a turbocharger, and includes a compressor 41, a turbine 42, a rotating shaft 43, a wastegate valve 44, and a blow-off valve 45. The compressor 41 is disposed upstream of the intercooler 25 in the intake pipe 23. The turbine 42 is disposed upstream of the purification device 37 in the exhaust pipe 35. The rotating shaft 43 connects the compressor 41 and the turbine 42. The wastegate valve 44 is provided in a bypass pipe 36 that connects the upstream side and downstream side of the turbine 42 in the exhaust pipe 35, and is controlled by an electronic control unit 70. The blow-off valve 45 is provided in a bypass pipe 24 that connects the upstream side and downstream side of the compressor 41 in the intake pipe 23, and is controlled by the electronic control unit 70.

[0021] In this turbocharger 40, the opening degree of the wastegate valve 44 is adjusted to adjust the distribution ratio between the amount of exhaust gas flowing through the bypass pipe 36 and the amount of exhaust gas flowing through the turbine 42, thereby adjusting the rotational driving force of the turbine 42, adjusting the amount of air compressed by the compressor 41, and adjusting the supercharging pressure (intake pressure) of the engine 12. In detail, the distribution ratio is adjusted so that the smaller the opening degree of the wastegate valve 44, the smaller the amount of exhaust gas flowing through the bypass pipe 36 and the larger the amount of exhaust gas flowing through the turbine 42. When the wastegate valve 44 is fully open, the engine 12 can operate in the same manner as a naturally aspirated engine without the turbocharger 40.

[0022] In addition, in the turbocharger 40, when the pressure downstream of the compressor 41 in the intake pipe 23 is somewhat higher than the pressure upstream of the intake pipe 23, the blow-off valve 45 is opened to release the excess pressure downstream of the compressor 41. Note that, instead of a valve controlled by the electronic control unit 70, the blow-off valve 45 may be configured as a check valve that opens when the pressure downstream of the compressor 41 in the intake pipe 23 becomes somewhat higher than the pressure upstream of the intake pipe 23.

[0023] Oil (hydraulic oil) stored in an oil pan 50 disposed below the engine 12 and the transmission (not shown) is supplied to the engine 12 and the transmission by an oil pump 52. The oil pump 52 is a mechanical pump driven by the rotational drive of the crankshaft 14, and pumps the oil stored in the oil pan 50 to an oil pipe 54. An oil branch pipe 55 is connected to the oil pipe 54, and an oil injection nozzle 56 that injects oil onto the back side of the piston 33 is attached to the oil branch pipe 54.

[0024] The electronic control unit 70 is configured as a microprocessor with a CPU at its core, and in addition to the CPU, is equipped with a ROM for storing processing programs, a RAM for temporarily storing data, a non-volatile flash memory for storing and holding data, an input / output port, and a communication port. Signals from various sensors are input to the electronic control unit 70 via the input ports.

[0025] Examples of signals input to the electronic control unit 70 include a tank internal pressure Ptnk from an internal pressure sensor 11a that detects the pressure inside the fuel tank 11, a crank angle θcr from a crank position sensor 14a that detects the rotational position of the crankshaft 14 of the engine 12, a coolant temperature Tw from a water temperature sensor 38f that detects the temperature of the coolant for the engine 12, and a throttle opening TH from a throttle position sensor 26a that detects the opening of the throttle valve 26. Another example of signals input to the electronic control unit 70 is a cam position θca from a cam position sensor (not shown) that detects the rotational positions of an intake camshaft that opens and closes the intake valve 30 and an exhaust camshaft that opens and closes the exhaust valve 34. Other examples include the intake air amount Qa from the air flow meter 23a attached upstream of the compressor 41 of the intake pipe 23, the intake air temperature Tin from the intake air temperature sensor 23t attached upstream of the compressor 41 of the intake pipe 23, the intake pressure (pre-compressor pressure) Pin from the intake pressure sensor 23b attached upstream of the compressor 41 of the intake pipe 23, and the boost pressure Pc from the boost pressure sensor 23c attached between the compressor 41 of the intake pipe 23 and the intercooler 25. Other examples include the surge pressure (post-throttle pressure) Ps from the surge pressure sensor 27a attached to the surge tank 27, and the surge temperature Ts from the temperature sensor 27b attached to the surge tank 27. Other examples include the low-pressure fuel pressure Pfp from the fuel pressure sensor 28a that detects the pressure of the fuel supplied to the port injection valve 28, and the high-pressure fuel pressure Pfd from the fuel pressure sensor 29a that detects the pressure of the fuel supplied to the in-cylinder injection valve 29. Examples of the air-fuel ratio include a front air-fuel ratio AF1 from a front air-fuel ratio sensor 35a attached upstream of the purification device 37 of the exhaust pipe 35, and a rear air-fuel ratio AF2 from a rear air-fuel ratio sensor 35b attached downstream of the purification device 37 of the exhaust pipe 35. Another example is the oil temperature Poil from an oil temperature sensor 51 attached to the oil pan 50.

[0026] Various control signals are output from the electronic control unit 70 via the output port. Examples of signals output from the electronic control unit 70 include a control signal to the alternator 15, a control signal to the throttle valve 26, a control signal to the port injection valve 28, a control signal to the in-cylinder injection valve 29, and a control signal to the spark plug 32. Examples of the signals output from the electronic control unit 70 include a drive signal to the fan motor 38d and the water pump 38e of the engine cooling device 38, and a drive signal to the fan motor 39d and the circulation pump 39e of the intercooler cooling device 39. Examples of the signals include a control signal to the wastegate valve 44, a control signal to the blow-off valve 45, and a control signal to the solenoid valve 18a.

[0027] The electronic control unit 70 calculates the rotation speed Ne and the load factor KL (the ratio of the volume of air actually taken in one cycle to the stroke volume per cycle of the engine 12) of the engine 12. The rotation speed Ne is calculated based on the crank angle θcr from the crank position sensor 14a. The load factor KL is calculated based on the amount of intake air Qa from the air flow meter 23a and the rotation speed Ne.

[0028] In the engine system 10 of this embodiment configured as described above, the electronic control unit 70 performs intake air amount control that controls the opening of the throttle valve 26, fuel injection control that controls the amount of fuel injected from the in-cylinder injection valve 28, ignition control that controls the ignition timing of the spark plug 31, supercharging control that controls the opening of the wastegate valve 44, and fuel pressure control in the high-pressure supply pipe 19 by opening and closing the solenoid valve 18a, based on the required load rate KL* of the engine 12.

[0029] Next, the operation of the engine device 10 of the embodiment, in particular, the state in which the load of the engine 12 is limited based on the oil temperature Toil will be described. Fig. 3 is a flowchart showing an example of the engine load limiting process executed by the electronic control unit 70 of the embodiment. This engine load limiting process is repeatedly executed at predetermined time intervals.

[0030] When the engine load limiting process is executed, the electronic control unit 70 first executes a process of inputting data required for the process, such as the rotation speed Ne of the engine 12, the required load factor KL* of the engine 12, and the oil temperature Toil from the oil temperature sensor 51 (step S100).

[0031] Next, the upper limit value (load upper limit value) KLlim of the load factor KL is set based on the rotation speed Ne and the oil temperature Toil of the engine 12 (step S110). In this embodiment, the relationship between the rotation speed Ne of the engine 12, the oil temperature Toil, and the load upper limit value KLlim is obtained in advance by experiments or the like and stored as a load upper limit value setting map, and when the rotation speed Ne and the oil temperature Toil of the engine 12 are given, the corresponding load upper limit value KLlim is derived from the map and set. FIG. 4 shows an example of the load upper limit value setting map. In the figure, the dashed line is a limit line when the oil temperature Toil is near the lower limit of the oil temperature range that requires the load factor KL to be limited, the two-dot chain line is a limit line when the oil temperature Toil is near the upper limit of the oil temperature range that requires the load factor KL to be limited, and the one-dot chain line is a limit line when the oil temperature Toil is an intermediate temperature between the temperature at the dashed line and the temperature at the two-dot chain line. In this embodiment, as shown in the figure, the load upper limit value KLlim is set to be smaller (the limit is greater) as the oil temperature Toil increases in the low revolution range of the engine 12.

[0032] Once the load upper limit value KLlim is set in this manner, the required load rate KL* is guarded against its upper limit by the load upper limit value KLlim (step S120), and this process ends. As described above, the required load rate KL* whose upper limit is guarded is used for intake air amount control that controls the opening of the throttle valve 26, fuel injection control that controls the fuel injection amount from the in-cylinder injection valve 28, ignition control that controls the ignition timing of the spark plug 31, supercharging control that controls the opening of the wastegate valve 44, and fuel pressure control in the high-pressure supply pipe 19 by opening and closing the solenoid valve 18a, etc.

[0033] In the engine device 10 of the embodiment described above, a load upper limit value KLlim is set that decreases (the limit becomes greater) as the oil temperature Toil increases in the low rotation range of the engine 12, and the required load rate KL* is upper-guarded by the load upper limit value KLlim. This makes it possible to prevent the oil from becoming too hot. As a result, it is possible to prevent the oil pressure from decreasing due to the oil becoming too hot, making it difficult to perform the oil jet that cools the piston 33 by injecting oil from the oil injection nozzle 56 onto the inside of the piston 33.

[0034] In the engine device 10 of the embodiment, the load upper limit value KLlim is set so that it becomes smaller (more restricted) as the oil temperature Toil is higher in the low rotation range of the engine 12, and the required load rate KL* is guarded at the upper limit by the load upper limit value KLlim. However, instead of the upper limit guard of the required load rate KL*, something equivalent to the required load rate KL* may be used. For example, the upper limit value (torque upper limit value) of the output torque of the engine 12 may be set so that it becomes smaller (more restricted) as the oil temperature Toil is higher in the low rotation range of the engine 12, and the output torque of the engine 12 may be guarded at the upper limit by the torque upper limit value, or the upper limit value (air amount upper limit value) of the intake air amount of the engine 12 may be set so that it becomes smaller (more restricted) as the oil temperature Toil is higher in the low rotation range of the engine 12, and the intake air amount of the engine 12 may be guarded at the upper limit by the air amount upper limit value.

[0035] In the engine device 10 of the embodiment, the load upper limit value KLlim is set so that it becomes smaller (the limit is greater) as the oil temperature Toil is higher in the low rotation range of the engine 12, and the required load rate KL* is upper-limit-guarded by the load upper limit value KLlim. However, the load upper limit value KLlim may be set so that it becomes smaller (the limit is greater) as the oil temperature Toil is higher in the entire rotation range of the engine 12, and the required load rate KL* may be upper-limit-guarded by the load upper limit value KLlim.

[0036] In the engine device 10 of the embodiment, the engine 12 used has an in-cylinder injection valve 29 arranged approximately in the center of the top of the combustion chamber 31, but it is also possible to use an engine in which the in-cylinder injection valve 29 is arranged on the side wall (side) of the combustion chamber 31.

[0037] In the engine device 10 of the embodiment, the engine 12 has a port injection valve 28 and an in-cylinder injection valve 29, but it may also be an engine having only a port injection valve 28 or an engine having only an in-cylinder injection valve 29.

[0038] Although the engine device 10 of the embodiment is provided with the engine 12 having the turbocharger 40, it may be provided with an engine that does not have the turbocharger 40.

[0039] In the engine system 10 of the embodiment, the supercharger 40 is configured as a turbocharger in which a compressor 41 disposed in the intake pipe 23 and a turbine 42 disposed in the exhaust pipe 35 are connected via a rotating shaft 43. However, instead of this, the supercharger may be configured as a supercharger in which a compressor driven by the engine 12 or a motor is disposed in the intake pipe 23.

[0040] The relationship between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem will be described below. In the embodiment, the engine 12 corresponds to the "engine", the oil pump 52, the oil pipe 54, the oil branch pipe 55, and the oil injection nozzle 56 correspond to the "oil injection mechanism", and the electronic control unit 70 corresponds to the "control device".

[0041] The correspondence between the main elements of the Examples and the main elements of the invention described in the Summary of the Problem column does not limit the elements of the invention described in the Summary of the Problem column, since the Examples are examples for specifically explaining the mode for implementing the invention described in the Summary of the Problem column. In other words, the interpretation of the invention described in the Summary of the Problem column should be based on the description in that column, and the Examples are merely a specific example of the invention described in the Summary of the Problem column.

[0042] Although the form for carrying out the present invention has been described above using examples, the present invention is not limited to these examples in any way, and it goes without saying that the present invention can be carried out in various forms without departing from the scope of the gist of the present invention. [Industrial Applicability]

[0043] The present invention can be used in the engine device manufacturing industry and the like. [Explanation of symbols]

[0044] 10 engine device, 11 fuel tank, 11a internal pressure sensor, 11p feed pump, 12 engine, 14 crankshaft, 14a crank position sensor, 16 fuel supply device, 17 low pressure supply pipe, 18 high pressure pump, 18a solenoid valve, 18b check valve, 18c plunger, 19 high pressure supply pipe, 22 air cleaner, 23 intake pipe, 23a air flow meter, 23b intake pressure sensor, 23c boost pressure sensor, 24 bypass pipe, 25 intercooler, 26 throttle valve, 26a throttle position sensor, 27 surge tank, 27a surge pressure sensor, 27b temperature sensor, 28 in-cylinder injection valve, 28a fuel pressure sensor, 29 intake valve, 30 combustion chamber, 31 spark plug, 33 piston, 33a piston top surface, 33b top ring groove bottom, 33c bottom ring groove bottom, 33d pin hole top, 34 exhaust valve, 35 exhaust pipe, 35a front air-fuel ratio sensor, 35b rear air-fuel ratio sensor, 36 bypass pipe, 37 purification device, 38 engine cooling system, 38a circulation flow path, 38b radiator, 38c fan, 38d fan motor, 38e water pump, 38f temperature sensor, 40 turbocharger, 41 compressor, 42 turbine, 43 rotating shaft, 44 wastegate valve, 45 blow-off valve, 50 oil pan, 52 oil pump, 54 oil pipe, 55 oil branch pipe, 56 oil injection nozzle, 70 electronic control unit.

Claims

1. The engine, an oil injection mechanism that injects oil to lubricate the engine onto a piston; A control device for controlling the engine; An engine device comprising: The control device largely limits the engine load when the oil temperature is high compared to when the oil temperature is low only in a low rotation range of the engine where an event occurs in which oil does not reach the piston even if oil jet is performed. An engine device characterized by:

2. 2. The engine device according to claim 1, The control device sets a load upper limit value in accordance with the oil temperature and limits the engine load so that the engine load is guarded at the load upper limit value. Engine equipment.

Images