JP2012225249A - Lubricating oil supply device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubricant supply device free from a lack of oil.SOLUTION: The lubricating oil supply device 10 includes a main oil pump 38 driven by an internal combustion engine, an oil strainer 36 arranged in an oil pan 22, a first oil suction line 42 to connect the oil strainer 36 and the main oil pump 38, a second oil supply line 44 to connect the main oil pump 38 and the inside of the internal combustion engine 12, and an auxiliary oil pump 40 that is installed in the first oil suction line 42 and operates when the oil pressure in the second oil supply line 44 reduces to a predetermined value or lower.

Description

  The present invention relates to a lubricating oil supply device for an internal combustion engine provided with a mechanically driven oil pump.

  In general, an internal combustion engine (also referred to as an “engine”) stores lubricating oil in an oil pan provided at a lower portion, and the lubricating oil is sucked from the oil pan by an oil pump, and is applied to each part of the internal combustion engine such as a bearing and a piston. Supply. In recent years, a vehicle with a so-called idle stop function that stops the operation of the engine when a vehicle stops by a signal, or a drive motor mounted together with the engine, travels by appropriately selecting the drive source of the engine and the drive motor A so-called hybrid vehicle is known.

  When the engine is stopped while waiting for a signal, when the driver performs an operation desired to start, such as depressing the accelerator pedal, the engine is immediately started and the vehicle can be started. Further, in the hybrid vehicle, the operation of the engine is stopped when the driving of the engine is not required, and the engine is appropriately started when generating power or when the driving force is required.

  In a lubricating oil supply device for an internal combustion engine, an oil pump is usually connected to a driving shaft such as an engine, and the lubricating oil is pumped by using the engine as a driving source. Therefore, when the operation of the engine stops, the oil pump also stops, and the supply of lubricating oil to each part of the engine stops.

  When the oil pump stops, the lubricating oil flows down from the bearings, etc., and the lubricating oil in the oil passage returns to the oil pan, and even if the engine is started, the lubricating oil is supplied until the lubricating oil is supplied to the bearing. There may be a temporary situation in which no is supplied.

  In a vehicle with an idle stop function or a hybrid vehicle, the engine is frequently stopped and started repeatedly, so that a state in which lubricating oil is not temporarily supplied occurs. It is considered that wear due to the oil film running out of the bearing supporting the shaft occurs.

  Therefore, in order to prevent such wear, for example, while the engine is stopped, the electric oil pump is operated, and the electric oil pump pumps the lubricating oil into the engine, or the oil passage into which the lubricating oil flows into the oil pump. Various inventions are known in which a check valve is provided so that the lubricating oil does not return to the oil pan even when the oil pump is stopped.

JP 2004-332886 A Japanese Patent No. 4154267 JP 2009-209885 A Japanese Patent Laid-Open No. 03-286114

  However, when an electric oil pump is provided, it is necessary to separately assemble parts, to separately form an oil passage, and to change the program of the control device, resulting in cost and labor. It was.

  In addition, when a check valve is provided in the oil passage, the lubricating oil cannot be supplied to the bearing or the like while the engine is stopped, and the lubricating oil is temporarily not supplied when the engine is started. Has occurred.

  The present invention solves the above-described problems and provides a lubricating oil supply device for an internal combustion engine that prevents the occurrence of wear due to oil film breakage at a sliding portion inside the internal combustion engine even in an internal combustion engine that is repeatedly stopped and started. Objective.

According to the present invention, a lubricating oil supply device for an internal combustion engine is configured as follows.
A lubricating oil supply device for an internal combustion engine includes a main oil pump driven by the internal combustion engine, an oil strainer disposed in an oil pan, a first oil passage for suction connecting the oil strainer and the main oil pump, Lubricating oil supply device from a second oil passage for supply leading from the oil pump to the inside of the internal combustion engine, and a sub oil pump provided in the first oil passage and operating when the oil pressure in the second oil passage falls below a predetermined value Configured.

  The auxiliary oil pump of the internal combustion engine is activated when the hydraulic pressure in the second oil passage falls below a predetermined value, such as when the engine is stopped, and sends out lubricating oil. Thereby, even when the engine is stopped, the lubricating oil is sent into the engine, and the oil film can be prevented from being cut. When the engine is restarted, the lubricating oil is immediately sent out from the oil pump, so that no non-lubricated time zone immediately after the engine starts is generated.

It is a lineblock diagram showing an internal-combustion engine provided with a lubricating oil supply device concerning one embodiment of the present invention. It is a perspective view which shows the same lubricating oil supply apparatus.

A lubricating oil supply device for an internal combustion engine according to an embodiment of the present invention will be described.
FIG. 1 shows an internal combustion engine (hereinafter referred to as “engine”) 12 having a lubricating oil supply device 10.

  The engine 12 is, for example, a diesel engine, and includes a cylinder 14, a cylinder head 16 provided on the upper portion of the cylinder 14, a piston 18, a crank mechanism 20, an oil pan 22, and the like. The engine 12 is not limited to a diesel engine but may be a gasoline engine or the like.

  A piston 18 is provided in the cylinder 14 so as to reciprocate. The cylinder head 16 is provided with a cam shaft 24, an intake valve 26, an exhaust valve 28, and the like. The cam shaft 24 is rotatably provided on the cylinder head 16 by a bearing. The intake valve 26 and the exhaust valve 28 are attached to the cylinder head 16 so as to be capable of reciprocating in the axial direction, and are driven by the cam shaft 24.

  In the crank mechanism 20, one end of a connecting rod 30 is connected to the piston 18, and a crankshaft 32 is rotatably attached to a crank bearing 34. An oil pan 22 is provided below the cylinder 14. A specified amount of lubricating oil is stored in the oil pan 22, and the lubricating oil supply device 10 is disposed.

  As shown in FIG. 2, the lubricating oil supply device 10 includes an oil strainer 36, a main oil pump 38, a sub oil pump 40, and the like. The oil strainer 36 is a coarse filter such as a wire mesh, and is disposed inside the oil pan 22 so as to be immersed in the lubricating oil stored in the oil pan 22.

  The main oil pump 38 is a conventionally known mechanical oil pump, for example. The gear 33 connected to the crankshaft 32 and the drive gear 35 mesh with each other, and are driven by the rotation of the crankshaft 32. Send lubricant to A first oil passage 42 is connected to the suction port of the main oil pump 38. The other end of the first oil passage 42 is connected to the oil strainer 36, and when the main oil pump 38 is driven, the lubricating oil stored in the oil pan 22 is sucked through the oil strainer 36.

  A second oil passage 44 is attached to the discharge port of the main oil pump 38. The second oil passage 44 communicates with the inside of the engine 12 and supplies lubricating oil to, for example, the camshaft 24, the crankshaft 32, the intake valve 26, the exhaust valve 28, and the like. A pressure switch 46 is provided in the second oil passage 44.

  The pressure switch 46 is a switch that detects the hydraulic pressure in the second oil passage 44 and opens and closes an electrical contact. The main power supply and the sub oil pump 40 that energize the in-vehicle battery 49 when the main key 47 of the vehicle is turned on. Are provided in the middle of the power line 48 connecting the two. The pressure switch 46 is normally in a closed state, and an electrical contact is opened when the pressure value of the lubricating oil in the second oil passage 44 exceeds a predetermined value. The predetermined value at which the contact of the pressure switch 46 is opened is, for example, a pressure indicated when the engine 12 is operated and the main oil pump 38 supplies lubricating oil into the second oil passage 44 in a normal state.

  The auxiliary oil pump 40 is, for example, a non-contact drive type axial flow pump, and is installed in the first oil passage 42 downstream of the oil strainer 36. The auxiliary oil pump 40 has a driving motor 50 and a pressure feeding blade 52. When power is supplied to the driving motor 50, the auxiliary oil pump 40 sucks the lubricating oil stored in the oil pan 22 through the oil strainer 36, and the main oil Pump to pump 38.

  The auxiliary oil pump 40 does not open the electrical contact of the pressure switch 46 and supplies lubricating oil to at least the crank bearing 34 that supports the crankshaft 32, thereby generating a pumping pressure that lubricates the crankshaft 32. . Therefore, the auxiliary oil pump 40 does not require a high pumping pressure until the lubricating oil is supplied to the camshaft 24 and the intake valve 26 provided in the cylinder head 16. Further, the sub oil pump 40 is configured so as not to give passage resistance to the lubricating oil passing through the first oil passage 42 by the operation of the main oil pump 38.

  Next, the operation of the lubricating oil supply device 10 will be described.

  When the engine 12 is operating, the main oil pump 38 is driven by the engine 12 through the gear 33, sucks the lubricating oil from the oil pan 22, and pumps the lubricating oil into the engine 12. The lubricating oil pumped from the main oil pump 38 passes through the second oil passage 44 and is supplied to the crankshaft 32, the camshaft 24, the intake valve 26, the exhaust valve 28, etc., and lubricates them.

  Since the hydraulic pressure in the second oil passage 44 exceeds a predetermined value, the pressure switch 46 is opened and power is not supplied to the sub oil pump 40. Further, since the auxiliary oil pump 40 hardly gives resistance to the flowing lubricating oil, the lubricating oil sucked from the oil pan 22 is smoothly supplied to various locations inside the engine 12.

  For example, when a vehicle with an idle stop function stops due to a signal or the like, the engine 12 stops and the operation of the main oil pump 38 stops. On the other hand, in order to stop the engine waiting for a signal, since the main key 47 is turned on, the contact of the pressure switch 46 is closed due to a decrease in the oil pressure in the second oil passage 44, and the in-vehicle battery 49 is connected to the sub oil pump 40 through the power line 48. Power is supplied.

  When power is supplied to the sub oil pump 40 and the sub oil pump 40 is activated, the sub oil pump 40 sucks the lubricating oil from the oil pan 22 and pumps the lubricating oil to the main oil pump 38 through the first oil passage 42. . Further, the sub oil pump 40 supplies the lubricating oil to the crank bearing 34 of the crankshaft 32 through the main oil pump 38 and the second oil passage 44.

  Therefore, even when the engine 12 is stopped, the lubricating oil is supplied to the crankshaft 32 in the case of a temporary stop such as waiting for a signal. Even when the signal is switched and the engine 12 is started, since the lubricating oil is supplied to the crankshaft 32 by the sub oil pump 40, the crankshaft 32 does not cause an oil film breakage with the crank bearing 34. Driven.

  Further, since the lubricating oil is supplied to the crankshaft 32 while the engine 12 is stopped, the lubricating oil is immediately pumped into the engine 12 when the main oil pump 38 starts operating, and lubrication is performed immediately after the engine is started. It does not cause a state where oil is not supplied.

  Thus, for example, in a vehicle with an idle stop function or a hybrid vehicle, even if the mounted engine 12 is frequently stopped and started repeatedly due to a signal waiting or power generation work, the oil film runs out on the sliding portion of the engine 12. It will not cause wear caused by

  The present invention can be used for an internal combustion engine equipped with an oil pump.

  DESCRIPTION OF SYMBOLS 10 ... Lubricating oil supply device 12 ... Engine 18 ... Piston 20 ... Crank mechanism 22 ... Oil pan 32 ... Crank shaft 34 ... Crank bearing 36 ... Oil strainer 38 ... Main oil pump 40 ... Sub oil pump 42, 44 ... Oil path 46 ... Pressure switch 47 ... Main key 48 ... Power line 49 ... In-vehicle battery 50 ... Drive motor 52 ... Pumping blade

Claims (3)

A main oil pump driven by an internal combustion engine;
An oil strainer disposed in an oil pan of the internal combustion engine;
A first oil passage for suction connecting the oil strainer and the main oil pump;
A second oil passage for supply leading from the main oil pump into the internal combustion engine;
An internal combustion engine comprising: a sub oil pump provided in the first oil passage, which is activated when a hydraulic pressure in the second oil passage falls below a predetermined value and supplies lubricating oil into the internal combustion engine. Engine lubricant supply device. The auxiliary oil pump is an axial flow pump and is provided inside the first oil passage,
In the second oil passage, a pressure switch that senses the pressure in the second oil passage and operates an electrical contact is provided,
2. The lubricating oil supply device for an internal combustion engine according to claim 1, wherein a power source that is energized with the main switch of the vehicle closed is connected to the auxiliary oil pump via the pressure switch.   3. The internal combustion engine according to claim 1, wherein the internal combustion engine is mounted on a vehicle that interrupts the operation of the internal combustion engine when temporarily stopped, or a vehicle that has a drive mechanism different from the internal combustion engine. Engine lubricant supply device.

Images