JP3898083B2 - Method for injecting lubricating oil into a cylinder of an internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for injecting lubricating oil into a cylinder of an internal combustion engine, in particular, a two-stroke crosshead engine, which is applied to a lubricating pipe that interconnects a pump outlet and a nozzle valve at a lubricating point. When the pump is periodically operated to supply a quantity of lubricating oil (dose) and the pressure in the lubricating pipe exceeds a predetermined opening pressure, the nozzle valve opens to spray the lubricating oil into the cylinder. It is related to the method.
[0002]
[Prior art]
Such a method is known from International Application No. 00/28194, which includes an inner surface of a cylinder liner in which nozzle valves are distributed in a row along the periphery of the cylinder liner and are located close to the nozzle. It is described that the direction of the nozzle is set so that the lubricating oil is sprayed on a part of the nozzle. Multiple nozzles, such as ten, are used to allow the lubricant to be distributed over the entire circumference of the liner.
[0003]
Regarding the supply of lubricant to the nozzle, International Application No. 00/28194 states that the ability to compress the lubricant in the lubrication tube makes it difficult to accurately supply the lubricant in terms of time. It is described as one problem. One condition for spraying the lubricant as intended is that, when supplied, the lubricant must exceed the nozzle valve opening pressure known from normal fuel injection. . When fuel is injected, the oil is supplied very quickly and appropriately in large quantities, so that the pressure in the oil pipe between the pump and the nozzle rapidly exceeds the nozzle opening pressure when the fuel pump supplies oil early. As a result, when injection starts, it is normal for that amount of fuel to be continuously supplied from the pump to the cylinder for 10 to 50 times longer than the time required to obtain the opening pressure. is there.
[0004]
The spraying of lubricating oil into the cylinder is further known from Japanese Published Application No. 7-34837 in 1995. According to this published application, the lubricating oil is injected into the cylinder cover when fuel is injected. It injects through the nozzle valve arrange | positioned. In this case, the lubricating oil pump is connected in the stroke direction to the crankshaft of the internal combustion engine. Therefore, every time the engine rotates, the lubricating oil is supplied to the inner surface of the cylinder liner by spraying.
[0005]
The Applicant's Danish patent 81275 in 1954 allows the supply of lubricating oil to be intermittently adapted to the engine speed (rpm), for example, for each engine revolution. A lubricating oil device is described in which lubricating oil is supplied to a lubricating portion on the inner surface of a cylinder liner every two or three revolutions. A controlled shut-off valve must be inserted in the lubrication pipe in close proximity to each lubrication location so that lubricating oil can be supplied to the lubrication location in a precise time for the piston operation. There is. Each time a lubrication point has to be lubricated, the lubrication pump supplies a precisely set amount of lubrication until the piston is in a position opposite the lubrication point, which is reduced by a shut-off valve. It must be kept under pressure. At that exact point, the shut-off valve is actuated and the lubricating oil is expelled and flows out of the lubricating point, at which time the piston ring can distribute the oil in the circumferential direction of the cylinder lie. In order to prevent a pressure drop in the lubrication tube during valve actuation, there must be a small accumulation volume in the tube that keeps the oil pressurized by the spring loaded piston. In a known lubricating device of this type, the lubricating oil is supplied at a pressure of several bars.
[0006]
[Problems to be solved by the invention]
On the other hand, the lubricating oil in the lubricating oil device described above is supplied at a higher pressure than allowing the lubricating oil to be sprayed. Higher pressure causes a number of disadvantages on the supply side of the lubricant, one of which is that the amount of lubricant supplied may vary due to leakage. These disadvantages become more pronounced when more nozzle valves are used per cylinder, in which case the volume in the lubrication tube is proportional to the amount of lubricant supplied. Because it becomes larger.
[0007]
An object of the present invention is to provide a method that allows a relatively small amount of lubricating oil to be reliably supplied at high pressure.
[0008]
[Means for Solving the Problems]
In view of this, the method according to the present invention is such that the nozzle valve is closed at a pressure lower than its opening pressure, and the volume of lubricating oil from the pump through the check valve is between the check valve and the nozzle valve. When the pressure gradually increases while the lubricating oil is supplied to the volume from the pump, the lubricating oil is temporarily stored in the volume, and the pressure of the lubricating oil in the volume When the pressure exceeds the opening pressure of the nozzle valve, the accumulated amount of lubricating oil is discharged by spraying through the nozzle valve.
[0009]
The nozzle valve has a high opening pressure, and the lubricating oil supplied from the pump is pressurized to a high opening pressure within the volume between the check valve and the nozzle valve. Lubricating oil inevitably holds a certain amount of air, which is compressed to increase the pressure of the lubricating oil while additional lubricating oil is received in the volume so that the lubricating oil is contained in the volume. There is a possibility of accumulation. When the amount of accumulated lubricating oil becomes extremely large, the oil pressure exceeds the opening pressure of the nozzle valve, and the nozzle valve opens and sprays into the cylinder. The amount of lubricating oil supplied during spraying depends on the closing pressure of the nozzle valve, so if the closing pressure is low, there is a gap between the check valve and the nozzle valve than with a high closing pressure. A larger amount of lubricating oil is discharged from the volume of the oil. The check valve effectively keeps the volume closed at the supply end, which inevitably requires the lubricating oil to be discharged through the nozzle valve.
[0010]
In one embodiment, the lubricating oil is supplied from the pump through the check valve to the volume at several injection volumes, and when the lubricating oil injection volume is supplied to the volume, within this volume The pressure rises stepwise, and when the amount of the most recently supplied lubricating oil exceeds the pressure of the lubricating oil in the volume above the opening pressure of the nozzle valve, the lubricating oil is sprayed through the nozzle valve. By operating the lubrication pump multiple times, the accumulated pressure required for the lubricant can be supplied, the pump can be of smaller dimensions and still supply the total amount of lubricant required for a complete spray sequence . Thus, the pump has a smaller leakage area and is therefore less susceptible to pressure fluctuations due to leakage. The check valve at the free end of the volume of the lubrication tube, where the lubricant accumulates, is substantially free of leakage and can maintain pressure with a large overpressure in the lubrication tube for a long time. Thus, temporarily interrupting the supply of lubricating oil between the two operations of the pump is not a problem. This gradual pressure build-up can occur several times or many times, for example by opening the nozzle valve and spraying into the cylinder, before releasing the amount of lubricant stored by several or many pump strokes. Can continue over the course of the engine rotation.
[0011]
Using a lubrication pump that is controlled independently of the engine cycle, for example, during one revolution of the engine, immediately before the spraying of lubricating oil is performed, the pump is operated once or several times in quick succession, After that, it is possible to stop the operation, but preferably, the pump operates in proportion to the rotational speed (rpm) of the internal combustion engine, that is, for a predetermined engine speed. It is possible to actuate a number of times. As a result of this proportional operation, when the engine load decreases, the average amount of lubricating oil per unit time can be adjusted to decrease.
[0012]
Suitably, the pump is operated from 2 to 30 times, preferably up to 10 times per spray of lubricant. Thus, the pump need only supply a small portion of the total amount of lubricating oil. In order to supply the required amount of oil, since it is not possible to improve the leakage state when operated 30 times or more, it is usually desirable to keep the number of operations at a maximum of 10 times.
[0013]
In order to allow the use of relatively simple pumps, the injection of individual lubricants from the pumps causes the pressure in the volume between the check valve and the nozzle valve to be from 100 kPa to 1000 kPa (1 bar to 10 bar). ), Preferably 200 kPa to 500 kPa (2 bar to 5 bar). Since this supply is to supply a limited amount of lubricating oil to the closed tube volume on the nozzle side, similarly, the pressure in the volume is quite high, such as over 6000 kPa (60 bar). Sometimes a simple piston pump that supplies lubricant can be used.
[0014]
The supply state of the lubricating oil can be changed according to the engine load. In order to exceed the opening pressure, it is preferable that the pump must be operated more times when the internal combustion engine is operated at partial load than when it is operated at full load. This accepts a relatively large amount of leakage at part load, so that the pump can be designed with greater manufacturing tolerances and thus longer life.
[0015]
This method is further adapted to supply a larger amount of lubricating oil per kWh than the amount of lubricating amount per kWh at full load × P% when the partial load is P% at the full load of the internal combustion engine. It is preferable to develop. The lubrication device thus provides a nozzle valve whose opening pressure decreases with decreasing cylinder pressure, so that at any particular time during the compression stroke of the engine cycle, the cylinder pressure is less than at full load. By making the load lower, it can be designed to automatically change the amount of lubricating oil.
[0016]
In order to reduce the number of nozzle valves in each cylinder, a predetermined pressure in the range of 1500 kPa to 4000 kPa (15 bar to 40 bar) exceeding the cylinder pressure at the time of the engine cycle in which the lubricating oil is sprayed into the cylinder It is preferable that the nozzle valve is opened. This overpressure effectively sprays the lubricating oil, especially when the pressure is in the range of 3000 kPa to 4000 kPa (30 bar to 40 bar), so that the spray is very effective in the cylinder space. Through this, the oil can be sprayed as far as possible, whereby the lubricating oil can be applied in a state of being uniformly distributed over a preferable large portion of the inner surface of the cylinder liner.
[0017]
The opening pressure of the nozzle valve controls the strength of the spray of lubricating oil, while the frequency of spraying, and thus the amount of lubricating oil per spray, can be controlled by the closing pressure of the nozzle valve.
[0018]
The reaction pressure against the spray increases as the cylinder pressure increases, but it is preferable that the nozzle valve be opened when the cylinder pressure becomes higher than 40% of the maximum compression pressure of the internal combustion engine. Lubricating oil is preferably sprayed onto the upper portion of the cylinder liner working surface relative to the piston ring, because at that working surface the load on the liner material is maximized. Spraying the lubricant onto the working surface relatively later in the upper piston stroke reduces the time that the spray should take until the piston ring moves through the just lubricated working surface. This contributes to keeping the lubricating oil on top of the cylinder liner where the need for lubrication is greatest.
[0019]
In order to properly lubricate during partial load and compensate for loss of leakage when lubricating oil is pumped, the amount of supply per injection of the lubricant pump can be adjusted. The supply per injection can be increased as appropriate when the engine is operated at a partial load at low rpm (rpm), because this increases the supply time for the injection at the partial load. In spite of the increased leakage, it is possible to supply the same amount of lubricating oil in the volume between the check valve and the nozzle valve at the partial load as at the full load.
[0020]
In another embodiment, the amount of lubricating oil sprayed into the cylinder on average per revolution of the engine at full load × P% is a portion of P% at full load of the internal combustion engine. At the time of load, it is sprayed into the cylinder every rotation of the engine. In addition to being finely distributed and effectively sprayed as a result of pressure build-up in the volume between the check valve and the nozzle, adjusting the amount of lubricant depending on the load This brings about a cost advantage in that the specific consumption of is reduced. The effective spray obtained by accumulating pressure in the tube volume before the spray is discharged and the amount of lubricating oil per nozzle being appropriately large is a good distribution of lubricant on the inner surface of the liner. Therefore, the lower temperature level on the inner surface of the liner during partial load operation can also be used to reduce the amount of lubricant supplied. In this regard, it is not critical whether the pump is run several times using a relatively small pump or is continuous by feeding from a larger pump.
[0021]
In a further embodiment, the pump supplies a greater amount of lubricating oil per kWh at P% partial load of the full load of the internal combustion engine, which amount is the amount of lubricating oil per kWh at full load × Larger than P%. As described above, the spraying of the lubricating oil is preferably performed by automatically adjusting the injection amount of the lubricating oil depending on the load. In this respect as well, it is important whether the pressure accumulation is performed stepwise by operating the pump several times with a relatively small pump or continuously by supplying from a larger pump. Not.
[0022]
The invention will now be described in more detail with reference to the very schematic drawings.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
For simplicity, in some embodiments described below, the same type of component is indicated by the same reference number.
[0024]
A cylinder lubrication device is provided in an internal combustion engine such as an MC type two-stroke crosshead engine or a large four-stroke engine having a cylinder bore of 22 cm or more. The engine may comprise a number of cylinders, for example in the range of 4 to 28 cylinders. The cylinder bore can be, for example, in the range of 22 cm to 120 cm, preferably 60 cm to 100 cm. Each of the cylinders 1 includes a cylinder liner having a cylinder cover, and a piston 8 that travels in the liner and has a piston ring 9 that slides on the operating surface 10 along the liner inner surface. ing.
[0025]
In order to reduce wear on both the piston ring and the cylinder liner, the working surface must be lubricated with lubricating oil, which is performed by several nozzle valves 3 distributed along the periphery of the liner. Each of these nozzle valves has a valve needle 11 that is spring loaded so that it can abut against the valve seat 12. Downstream of the valve seat is one or more sprayer holes 13 drilled in the direction in which the lubricant should be sprayed during spraying. When the nozzle valve is closed, the tip 14 of the valve needle arranged radially in the valve seat is influenced by the pressure in the cylinder at the nozzle valve 3, and the pressure propagates through the hole in the sprayer. When the nozzle valve is open, the pressure in the cylinder is affected by a larger area of the entire tip of the valve needle, which means that the valve has a higher opening pressure than a closing pressure.
[0026]
Each nozzle valve 3 is connected to a lubrication pipe 4, and the lubrication pipe is connected to a pump 6 via a check valve 5. When activated, this pump supplies a certain amount of lubricating oil to the tube volume 15 defined between the check valve 5 and the nozzle valve 3. Lubricating oil is supplied to individual pumps 6 through conduits 7 at a pressure before the pump pressure. The lubricant functions as described above as a whole.
[0027]
In a two-stroke engine, the cylinder 1 can be of a uniflow type, in which case scavenging is performed while the exhaust valve 17 at the upper end of the cylinder is open and during subsequent filling of the cylinder, the scavenging port 16 at the lower end of the cylinder. Through the cylinder in the flow (arrow A in FIG. 2) in a well-known manner in swirl operation.
[0028]
As shown in FIG. 2, there are several, in this case four nozzle valves, in the circumferential direction of the cylinder. The uniform distribution of the nozzle valves 3 in the circumferential direction can advantageously be the same nozzle valve design in which each of the nozzle valves is adapted to supply cylinder lubricant to a similar area of the working surface. Bring a special point. It is also possible to arrange the nozzle valves at different heights in the cylinder, and these nozzle valves can also or alternatively be mounted in the cylinder cover. The number of the nozzle valves 3 of the cylinder depends on the diameter of the cylinder, and normally, when the cylinder bore is represented by B in cm, it is appropriate that the number is B / 10 ± 2.
[0029]
Preferably, each nozzle valve is associated with one pump 6. Typically, several pumps are grouped together in a single lubricator. This lubrication device can work on some or all engine cylinders in small engines, and can act on the lubrication points of a single cylinder in larger engines. It is possible to drive the pump piston by a camshaft which is mechanically driven or electrically driven by an electric motor connected to the camshaft, the operation in the former case being driven by the camshaft in the engine It is mechanically controlled via a chain drive or similar drive connection to the shaft, and in the latter case it is electronically controlled based on information about engine rotation. Preferably, however, the pump piston is driven by a hydraulic actuator on the basis of an electronic control signal, for example a so-called Alpha Lubricator manufactured by the applicant. There is one pump piston per actuator, but preferably several pump pistons associated with the same cylinder are driven together by a single actuator.
[0030]
An example of a lubrication device is illustrated in FIG. 3, in which case the tank 18 holds cylinder lubricating oil, which can be preheated by a heating device 19, not described in detail. Unlike all other lubricants used in larger engine devices, cylinder lubricants do not centrifuge in the separator prior to use. Cylinder lubricating oil is usually an acid neutralized oil with a high addition amount that retains calcium carbonate in a complex compound encapsulated in fine particles so that the calcium carbonate can be kept floating in the oil. These particles are removed from the cylinder lubricant by centrifugation. As a result of the lack of centrifugation, the cylinder lubricant inevitably contains fine bubbles.
[0031]
The primary pump 20 pumps the lubricating oil through the filter 21 to the supply conduit 22, from which the conduit 7 branches off to reach the actuator 25, the pump only being associated with the single cylinder 1 shown in the drawing. is doing. The accumulator 23 is connected to an actuator for the pump, and attenuates pressure fluctuations accompanying filling of the pump. Another accumulator 24 attenuates pressure fluctuations in the conduit 7. The pump 6 is controlled by a solenoid valve 26 connected to an electronic control device (not shown) via a signal line. The feedback sensor 27 provides information on the actual operation of the actuator piston to the control device. The return branch 28 returns excess lubricating oil to a return conduit 29 connected to the tank 18. The pressure control device 30 adjusts the pressure in the supply conduit to a predetermined value, for example in the range of 100 kPa to 6000 kPa (1 bar to 60 bar), typically in the range of 700 kPa to 2000 kPa (7 bar to 20 bar). .
[0032]
As shown in FIG. 2, the pump 6 can be a piston pump, and the amount of lubricating oil supplied by the piston pump is injected in a predetermined volume unit during each stroke of the pump. In practice, this has the advantage that slight variations in the air quantity of the lubricating oil take place at a relatively low pressure of the primary pump without any significant effect on the quantity of lubricating oil in the volume.
[0033]
During each operation, the pump 6 injects cylinder lubricating oil into the tube volume 15 via the check valve 5, which volume is in direct communication with the pressure chamber 31 in the nozzle valve 3. When the nozzle valve is closed, the pressure chamber is defined by the nozzle housing, the valve seat 12 and the valve needle 11. The needle is compressed by the compression spring 32 so as to contact the valve seat. The pressure in the pressure chamber affects the exposed area of the valve needle in the pressure chamber by an opening force that opposes the spring force. If one or more injections from the pump 6 cause a large amount of lubricating oil to be supplied by the pressure chamber and its internal pressure affects the valve needle with a force greater than the spring force, the valve needle will Displaced away from the valve seat and at the same time, pressurized lubricating oil flows forward toward one or more holes in the spraying device and sprayed into the cylinder. When the nozzle valve is opened, the pressure in the pressure chamber 31 affects the overall cross-sectional area of the valve needle, but when the nozzle valve is in the closed position, this pressure acts on the central area blocked by the valve seat. do not do. As a result of the larger area when in the open position, a pressure lower than the open pressure in the pressure chamber 31 can exceed the compressive force from the spring 32 and keep the valve needle in the open position. The valve needle changes to its closed position against the valve seat 12 only when the pressure in the pressure chamber drops below the closing pressure. This closing pressure is a pressure when the force from the spring 32 exceeds the pressure of the lubricating oil acting on the entire cross-sectional area of the valve needle 11.
[0034]
A compression spring 32 or another source that generates a closing force on the valve needle 11, such as a hydraulic pressure in the chamber 33, determines the opening pressure of the nozzle valve. The spring force or hydraulic pressure in the chamber 33 can be adjusted to change the opening force for the current operating state of the engine.
[0035]
The length of the lubrication pipe 4 depends on the distance between the pump 6 and the nozzle valve 3. Typically, the length of the pipe is considered to be in the range of 0.5 m to 8 m, for example, 3 m to 5 m, and the pipe diameter is sufficiently large so that the nozzle valve is operated once. It is preferable to select a size that is appropriately large so as to allow compression so as to obtain a volume corresponding to the amount of cylinder lubricating oil necessary for this. The lubrication tube 4 has, for example, an inner diameter of 5 mm, a length between the check valve 5 and the nozzle valve 3 of 4 m, and a tube volume of 31.4 cm. ^Three Can be. As a result of the experiment, the cylinder lubricant supply amount for this volume was about 0.1 cm. ^Three It was found that the pressure increased by about 500 kPa (about 5 bar).
[0036]
When the internal combustion engine is started, the pressure in the volume 15 is first raised to a level corresponding to the closing pressure Pc of the nozzle valve by operating a series of pumps, for example 4000 kPa to 15000 kPa (40 Bar to 150 bar), typically 5000 kPa to 13000 kPa (50 bar to 130 bar). These multiple operations can take place before or during engine startup. When cylinder lubricating oil is continuously supplied from the pump 6, the pressure in the volume 15 exceeds the nozzle valve opening pressure Po at a certain stage until the pressure in the volume drops below the closing pressure Pc. The lubricating oil is injected. As described above, the injection amount of the lubricating oil depends on the difference between the opening pressure and the closing pressure of the nozzle valve and the size of the volume 15. At the same time, the amount of lubricating oil injected corresponds to the total amount of lubricating oil supplied by the pump 6 during the two actuations of the nozzle valve.
[0037]
Since cylinder lubricants are expensive, it is preferable to minimize the amount of lubricant consumed per kWh generated by the cylinder. In order to achieve efficient lubrication that matches the consumption of the lubricating oil, a large amount of lubricating oil is appropriately injected per nozzle valve operation so that the oil is supplied to the operating surface in an optimal manner. It is desirable to do. This is not lubricated every engine revolution, and is 1 every multiple engine revolutions such as every 2 revolutions, every 3 revolutions, every 4 revolutions, every 5 revolutions, every 6 revolutions, every 7 revolutions or every 8 revolutions. It means that it is desirable to lubricate only once.
[0038]
In FIG. 4, the cam is operated by a camshaft that is reliably driven so that the pump rotates in proportion to the rotation of the crankshaft. Therefore, for example, every time the engine crankshaft rotates, the pump 6 is rotated once. The supply sequence that is activated is illustrated. At each operation, the pressure in the volume 15 rises in steps until the pressure at the last operation exceeds the opening pressure of the nozzle valve, at which time the lubricating oil is injected into the cylinder, The pressure in the volume drops sharply to the closing pressure Pc, at which time a new cycle with pressure build-up is started.
[0039]
FIG. 5 shows the supply sequence of the pump 6 designed so that a supply amount substantially corresponding to the amount supplied each time the nozzle valve 3 is opened can be supplied for each operation. Thus, the pressure in the volume 15 corresponds to the closing pressure Pc during most engine operating conditions, but the pump 6 is actuated just before the lubricating oil injection is to be performed and the pressure in the volume opens. An amount of lubricating oil is supplied so as to exceed the pressure Po, and then the lubricating oil is injected.
[0040]
By operating the pump quickly and continuously several times, it is possible to increase the pressure appropriately and greatly during the same engine cycle with the smaller pump 6. FIG. 6 shows the pressure sequence obtained when four quick and continuous actuations are performed, with the last actuation causing the pressure to exceed the nozzle valve opening pressure. This has the advantage that the amount of leakage during operation is small as a result of the small pump size, while the supply amount during operation is reasonably large.
[0041]
The engine may have a maximum compression pressure in the range of, for example, 5000 kPa to 14000 kPa (50 bar to 1400 bar), preferably in the range of 7500 kPa to 12500 kPa (75 bar to 125 bar). The opening pressure of the nozzle valve can be, for example, in the range of 1500 kPa to 15000 kPa (15 bar to 150 bar), preferably in the range of 3000 kPa to 7000 kPa (30 bar to 70 bar). Can exceed the current pressure in the cylinder. This desired excess pressure depends entirely on the characteristics of the injection. If it is desirable to inject small lubricant particles in the form of a very finely divided mist, the excess pressure must be relatively high so that a fine spray can be achieved. Instead, larger droplets, i.e. more continuous jets or fans (spread), that can be injected through a swirling air flow in the cylinder to obtain good penetration and can be safely injected onto the working surface If lubricating oil is injected in the form, and if the distance from the nozzle valve is relatively long, the excess pressure need not be so high. Injecting the lubricant in large droplets, ie, more continuous jet or fan-shaped injection conditions, is believed to allow the cylinder lubricant to be distributed to the most favorable state. This is because, due to its larger mass, large droplets are less dependent on cylinder gas movement and are less susceptible to fluctuations as they move. The nozzle geometry can be used to achieve the desired injection state, for example by increasing the diameter of one or more holes in the sprayer, the drop pressure can be reduced when the excess pressure is the same. The dimensions are larger and the direction of the hole determines the direction in which the lubricant is injected.
[0042]
In the present invention, supplying excess pressure lubricating oil through the nozzle valve means that the cylinder lubricating oil is larger in the form of finely distributed particles mist, ie, jet, fan shaped, or spherical lubrication. Regardless of whether it is injected in the form of oil injection, it is a special specific spray.
[0043]
The opening pressure Po depends on the arrangement position of the nozzle valve in the height direction of the cylinder. This relies on the compression pressure in the cylinder increasing while the piston moves upward. The more the nozzle valve is mounted in the cylinder, the higher the opening pressure required to achieve the same surplus pressure if the piston is to be injected during its ascent operation before passing through the nozzle valve.
[0044]
When the nozzle valve is arranged in the lower half of the cylinder, the opening pressure Po is hardly affected by the compression pressure. On the other hand, if the nozzle valve is positioned upwards, i.e. at the top of the cylinder, the compression pressure propagates through the hole in the sprayer and affects the area of the valve needle within the valve seat by the force acting in the opening direction. Therefore, the change in the compression pressure affects the opening pressure of the nozzle valve.
[0045]
This allows the compression pressure to be the injection release factor illustrated in FIG. The top dashed line shows the change in the opening pressure Po during the engine cycle, and the stepped solid line shows the increase in pressure in the volume 15 due to the supply of lubricating oil from the pump 6. The pressure in the volume 15 rises to a level higher than the minimum opening pressure Po, which ensures that the lubricant is injected before the piston reaches its top dead center (TDC). Conceivable.
[0046]
It is easy to design the lubricating tube 4 with a tube diameter that provides a suitable volume 15. If a shorter tube is desired, it is of course possible to associate the tube with a separate auxiliary element which is preferably formed as a fixed chamber connected to the tube or as an expanding part of the local tube. .
[0047]
The closing pressure Pc of the nozzle valve is suitably 50% to 96% of the opening pressure Po, preferably 75% to 95% of the opening pressure. If the opening pressure is lower, the injection amount will be larger, and the interval during which the nozzle valve is activated will be longer, or conversely, if the opening pressure is higher, the interval during which the nozzle valve is activated will be Shorter.
[0048]
The nozzle valve allows the oil injection direction to be controlled efficiently, which is compared to the conventional method of supplying the oil at a low pressure that penetrates into the oil groove on the inner surface of the cylinder. This makes it possible to select a series of supply methods. The nozzle valve is positioned directly above the scavenging port 16 and the nozzle valve is allowed to inject upwards in the cylinder, which passes before or after the piston passes the nozzle valve during the compression stroke. Regardless of whether the injection is performed later, the injection is allowed at a low pressure.
[0049]
The nozzle valve 3 can also be arranged in the cylinder, for example, approximately in the middle of the working surface, in which case the jet of lubricating oil is directed in the middle of the liner or in the region above the working surface or It can be oriented upwards or downwards towards the lower region.
[0050]
It is also possible to arrange the nozzle valve 3 in the upper part of the liner, in which the nozzle valve can inject lubricating oil onto the working surface before the piston passes through the nozzle valve.
[0051]
The ability to direct and inject cylinder lubricant provides the freedom to adapt the lubricant supply to the current needs of the cylinder. The direction of the valve so that lubricating oil can be injected in other directions, such as upwards or downwards, even when a through-bore is formed in the cylinder wall at a specific position of the cylinder so that a nozzle valve can be installed By changing, it is possible to change the supply of lubricating oil on the operating surface.
[0052]
Within the scope of the claims, it is possible to combine the details of the above embodiments into other embodiments. It is also possible to perform one or more injection procedures of cylinder lubricant during the engine cycle. Furthermore, this injection procedure can be modified in response to an engine load or a change in load, for example, where the required amount of lubrication temporarily increases with the operating conditions of the engine as seen from changes in the amount of lubricating oil supplied. it can.
[Brief description of the drawings]
FIG. 1 is a side view of a cylinder.
FIG. 2 is a diagram of a single cylinder with four nozzle valves.
FIG. 3 is a diagram of a cylinder lubricant supply device.
FIG. 4 is a diagram showing an example of a lubrication stage.
FIG. 5 is a diagram showing another example of the lubrication stage.
FIG. 6 is a diagram showing another example of the lubrication stage.
FIG. 7 is a diagram showing another example of the lubrication stage.
[Explanation of symbols]
1 cylinder 3 nozzle valve
4 Lubrication tube 5 Check valve
6 Pump 7 Pipe
8 Piston 9 Piston ring
10 working surface 11 valve needle
12 Valve seat 13 Sprayer hole
14 Valve needle tip 15 Tube volume
16 scavenging port 18 tank
19 Heating device 20 Primary pump
21 Filter 22 Supply conduit
23, 24 Accumulator 26 Solenoid valve
27 Feedback sensor 28 Return branch
29 Return conduit 30 Pressure control device
31 Pressure chamber 32 Compression spring
33 Chamber Pc Closing pressure
Po opening pressure TDC Top dead center

Claims (15)

A method of injecting lubricating oil to the internal combustion engine Kannai at lubrication points, lubrication pipe for connecting the pump outlet and the nozzle valve and (3) to each other with respect to (4), the injection of a predetermined amount for each of the lubricating oil pump so as to supply (6) is actuated periodically, closed Ji said nozzle valve is at a lower pressure than that opening pressure, lubricating oil supplied from the pump (6) is, the lubricant pipe (4 by) temporarily stored et al is that in, gradually increasing the pressure in the lubricating tube (4), when the pressure of the lubricating tube (4) within has Uwamawa' the opening pressure of the nozzle valve, the lubricant Is sprayed through the nozzle valve (3), the pump (6) is actuated 2 to 30 times for each spray of lubricant, and the injection of lubricant from the pump (6) is: In a volume (15) between the check valve and the nozzle valve via a check valve (5) As the supply of the lubricating oil is repeatedly supplied to the volume, the pressure in the volume increases stepwise, and the lubrication in the volume (15) is caused by the injection of the most recently supplied lubricating oil. A method characterized in that lubricating oil is sprayed through the nozzle valve (3) when the pressure of the oil exceeds the opening pressure of the nozzle valve . The method according to claim 1, wherein the internal combustion engine is a two-stroke crosshead engine.   3. A method according to claim 1 or 2, characterized in that the pump (6) is operated in proportion to the rotational speed (rpm) of the internal combustion engine, i.e. is operated a predetermined number of times during a predetermined engine speed. And the method.   4. A method according to any one of the preceding claims, characterized in that the pump is activated at most 10 times for each spray of lubricating oil. 5. The method according to any one of claims 1 to 4 , wherein the injection of the individual lubricating oil from the pump (6) is a volume (15) between the check valve (5) and the nozzle valve (3). Increasing the internal pressure by 100 kPa to 1000 kPa (1 bar to 10 bar). 6. The method according to claim 5 , wherein the injection of the individual lubricating oil from the pump (6) causes the pressure in the volume (15) between the check valve (5) and the nozzle valve (3) to be 200 kPa to 500 kPa ( 2) to 5 bar). The method according to any one of claims 1 to 6, in order of more than opening pressure, it is more numerous times when operating at partial load than when the internal combustion engine is operated at full load A method, characterized in that only the pump (6) has to be activated. The method according to any one of claims 1 to 7 , wherein when the partial load of P% at the full load of the internal combustion engine is a partial load of P%, the amount of lubrication per kWh at the full load is larger than the amount of P%. A method characterized in that lubricating oil per kWh is supplied. A method according to any one of claims 1 to 8, at the time of engine cycles the lubricating oil is sprayed into the cylinder (1), exceeds 1500kPa to 4000 kPa (15 bar to 40 bar) than the cylinder pressure A method characterized in that the nozzle valve opens at a predetermined pressure in the range. A method according to any one of claims 1 to 9, the nozzle valve, and wherein the opening at the time the cylinder pressure is equal to or more than 40% of the maximum compression pressure of the internal combustion engine, method. 11. The method according to any one of claims 1 to 10 , wherein the supply rate per injection of the lubricating oil pump is adjustable, and when the engine is operating at partial load, the supply rate is A method characterized by increasing appropriately. A method according to any one of claims 1 to 11, when the P% of partial load at full load of the internal combustion engine, lubricating sprayed into averagely cylinder for each rotation of the engine at full load A method, characterized in that a smaller amount of lubricating oil is sprayed into the cylinder (1) than the amount x P%. The method according to any one of claims 1 to 11 , wherein when the internal load engine has a partial load of P% at the full load, the pump is more than a lubrication amount per kWh at the full load x an amount of P%. Supplying a larger amount of lubricating oil per kWh. The method according to any one of claims 1 to 13, wherein the opening pressure of the nozzle valve (3) is adjustable, the method. A method according to any one of claims 1 to 14, wherein it closes the pressure of the nozzle valve (3) is adjustable, the method.

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