JP2001173423A - Engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubricating device having a simple structure, high accuracy, and certainty, in a two cycle large diesel engine especially. SOLUTION: The engine is provided with at least one cylinder, and a piston disposed inside thereof, the piston is reciprocatable along a sliding surface of the cylinder, and lubricant is supplied to the sliding surface through each lubricant delivery port 10 connected to each supplying pipe passage 16. Each rate regulating device 17 is disposed on each lubricant delivery port 10, and the rate regulating device 17 is connected to a control device 18. The rate regulating device is constituted as a switching valve 17 disposed in the vicinity of the lubricant delivery port 10, the supplying pipe passage 16 is selectively opened/closed by the switching valve, a necessary rate of the lubricant is found out on the basis of a measuring value having a relation to a lubricant amount demanded by the control device 18, and an opening time point and a closing time point of the switching valve 17 are led out on the basis thereof so as to properly control the switching valve.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine,
It relates to a large cycle diesel engine.
The engine addressed by the invention comprises at least one cylinder and a piston arranged therein, the piston being able to reciprocate along a sliding surface of the cylinder, which advantageously has Is provided on the cylinder side and is capable of supplying lubricant through a lubricant discharge port connected to an associated supply pipe, and each lubricant discharge port is provided with a regulator disposed in the supply pipe. A metering device, and a common rail assigned to the supply line of at least one group of lubricant outlets and containing the lubricant at a predetermined pressure, and a corresponding metering device. A control device having at least one input for a measured value correlated with the lubricant demand.

[0002]

2. Description of the Related Art An arrangement of this kind is disclosed in European Patent No. 6
It is known from 78 152. In this known configuration, the metering device assigned to the lubricant outlet is formed as a kind of metering pump whose capacity can be adjusted. In this case, the metering pump is operated for each piston stroke in the engine cycle. The amount of lubricant supplied is adjusted only by changing the capacity of the metering pump. If a metering device configured in the form of a metering pump is used, it is certain that an accurate volume setting can be obtained. However, known configurations are very costly and take up a lot of space. Therefore, the distance between the end of the lubricant discharge port on the sliding surface side and the associated metering device may be relatively large, which may cause an error at the start of actual lubrication.

[0003]

SUMMARY OF THE INVENTION The object of the present invention, which is based on the above, is to improve a construction of the kind mentioned at the beginning by simple and inexpensive means, so that the structure is simplified and, nevertheless, high. The goal is to obtain accuracy.

[0004]

SUMMARY OF THE INVENTION According to the invention, the object of the invention is to provide the metering device as a switching valve which is respectively adjacent to the associated lubricant outlet, by means of which the associated supply line is selectively provided. The control device determines the required amount of lubricant by using the input measurement value correlated with the lubricant demand, and determines at least the opening time and closing time of the switching valve based on the measured value. This is achieved by arranging the switching valve to be controlled accordingly.

[0005] The quantity of lubricant supplied to the sliding surface is advantageously determined here by the switching valve assigned to the lubricant outlet.
It is determined by the opening time that can be set by the control device. Therefore, there is an advantage that a metering pump for each lubricant discharge port, which is costly and occupies a large space, and whose capacity can be adjusted, is not required. The combination according to the invention takes advantage of the common rail combined with the short response time of the switching valve. The switching valve assigned to the lubricant outlet has a simple and robust construction, can be controlled with high reliability, and can be configured as a simple two-position valve requiring very short response times. it can. Since this switching valve can be provided immediately adjacent to the corresponding lubricant discharge port, there is no concern that there will be a significant time difference between the switching signal and the actual start of lubrication, which indicates the lubrication accuracy and the lubrication accuracy. Has an advantageous effect on the achievable service life of the sliding surface.
Moreover, with the arrangement according to the invention, it is advantageously possible to vary not only the opening time of the switching valve but also the frequency of the switching process. It is therefore advantageously possible to provide a relatively long distance between the individual lubrication steps and to supply a relatively large amount of lubricant at each lubrication step, which is Works positively on the entire sliding surface of the agent,
This has a positive effect on the achievable service life of the sliding surfaces. Nevertheless, an overall savings in lubricant demand is guaranteed.

[0006] Advantageous embodiments and expedient developments of the measures of the main claim are described in the dependent claims. For example, the individual lines assigned to each cylinder may be branched off from the common rail, which preferably passes through all the cylinders, and each individual line is connected to at least one annular line, It can be provided that the supply line of the lubricant outlet, which is preferably arranged at the same level and distributed over the circumference of the cylinder, branches off from the path. This measure creates a common supply loop for each of the plurality of lubricant outlets, which as a whole results in a simple and compact structure of the entire lubricating device.

[0007] Advantageously, the control device can be provided with outputs assigned to the cylinders, via which all the switching valves belonging to the assigned cylinder can be controlled. Thereby, the lubrication of each cylinder can be controlled independently of the lubrication of the neighboring cylinders, thereby taking into account special needs, for example, when replacing cylinder liners Is guaranteed.

A further advantageous measure can be seen in that the control device has at least an input for a signal corresponding to the engine cycle and the engine load. This has the advantage that the amount of lubricant can be set depending on the load, which guarantees the optimization of the lubricant used and the consequent savings in lubricant demand. I do. Furthermore, taking into account the engine cycle ensures that lubrication always takes place at a given piston position.

[0009] As a method suitable for the purpose, the control device determines the total amount of lubricant demand using the input value, and if the amount of lubricant is different from the flow rate of the lubricant flowing through the common rail, the opening time of the switching valve is determined. And / or configured to adapt the opening frequency. This makes a comparison between the setpoint value and the current value, so that the setpoint value is continuously adapted to the actual need. It has therefore been found that the arrangement according to the invention has a particularly low time lag, which guarantees an excellent precision of lubrication and a long service life of the lubricated sliding surfaces.

[0010] The control device can be embodied as a computer having a main control unit and a standby control unit which is activated when the main control unit fails. This effectively prevents the failure of the lubricating device, which guarantees high reliability.

[0011]

Further advantageous embodiments and suitable developments of the measures of the main claim are described in the further dependent claims and in the following embodiments with reference to the drawings. Details can be read from the description.

The main field of application of the present invention is large engines, such as two-cycle large diesel engines, especially used as marine navigation equipment. The structure and mode of operation of these types of engines are known per se.

Such an engine typically has a plurality of cylinders 1 arranged in series of the type shown in FIG. The cylinder has a cylinder liner 3 provided with an inflow slit 2, and a cylinder head 4 provided with a discharge device (not shown in detail) is mounted on the cylinder liner. Inside the cylinder 1 there is a piston 5 constituting a movable partition of a combustion chamber 6. The piston 5 is connected to a crosshead (not shown in detail) via a piston rod, and the crosshead cooperates with a crankshaft via a connecting rod. The piston 5 has a piston ring 8 arranged in an associated piston ring groove 7. In the illustrated embodiment, a plurality of piston rings 8 arranged one above the other are provided to constitute a so-called piston ring package.

The curved surface of the hole of the cylinder liner 3 is formed as a sliding surface 9 on which the circumferential surface of the piston ring 8 slides. The sliding surface 9 is lubricated with a suitable lubricant. For this purpose, the cylinder liner 3 is provided with a plurality of lubrication holes 10 distributed over the circumference of the cylinder, each terminating at a sliding surface 9, into which lubrication is supplied by a lubrication device. . This is shown only by the supply arrows in FIG. FIG. 1 shows two tiers arranged one above the other.
One lubrication hole 10 is shown. These represent, for example, lubricating holes 10 formed by a plurality of lubricating holes which are respectively distributed evenly over the cylinder circumference and are annularly arranged at the same height, and the state is clear from FIG. .

The lubricating device shown in FIG. 2 provided on the pistons 3 arranged side by side includes a common rail 11 passing through all the cylinders 3, the common rail being provided by a pump station 12 with a lubricant tank. 4
The supply of the lubricant taken out from 0 is received. The pump station 12 is configured such that the lubricant is supplied to the common rail 1 at a predetermined pressure.
1 is designed to be housed inside. In a purposeful manner, the pump station 12 has at least two
Have two pumps. In this case, when one of the pumps operates, the other pump is in a ready state so as to be able to immediately respond when the first pump fails. Thus, the other pump can function as a so-called standby pump. Common rail 11
There is a flow measuring device 13 adjacent to the pump station 12 inside the
Detect the full volume flow through.

The common rail 11 has an individual pipe line 14 assigned to the cylinder 3. In the form shown,
One individual conduit 14 is provided for each cylinder 3. The individual conduit 14 is connected to an annular conduit 15 arranged in the region of the cylinder 3,
It is connected to the assigned group of lubrication holes 10 via a supply line 16 which branches off radially from this. At this time, it is expedient if one annular conduit 15 is provided in each of the lubrication holes 10 of the cylinders 3 arranged at the same height. When two lubricating holes 10 arranged in an annular shape are arranged one above the other, two annular conduits 15 are provided correspondingly, and these annular conduits are the same in the illustrated embodiment. Are connected to the individual pipelines 14. Of course, it is also conceivable to provide each annular conduit 15 with its own individual conduit.

A switching valve 17 is disposed in each of the supply pipes 16 communicating with the lubrication holes 10. The switching valve may be a two-position valve having two switching points, open and closed. The switching valve 17 is expediently designed as an electromagnetically operable gate valve.

The amount of the lubricant supplied to the sliding surface 9 through the lubrication hole 10 can be easily known from the opening time and the opening frequency of the assigned switching valve 17. In FIG. 2, the switching valves 17 are shown separated from the corresponding cylinders 3 in order to make the corresponding cylinders easier to see. But,
In practice, the switching valve 17 can be mounted on the cylinder 3 or can be integrated into a corresponding cutout, so that the connection between the switching valve and the corresponding opening on the sliding face side of the lubrication hole 10 is provided. The distance is very short. This has a positive effect on the achievable accuracy.

The opening command and the closing command for the switching valve 17 detect the amount of lubricant demand, and correspond to the detected lubricant demand.
Is issued by the controller 18 which controls The control device 18 has at least one output 19 assigned to the cylinder 3. In the illustrated embodiment, a unique output unit 19 is provided for each cylinder 3. This allows simultaneous data transmission. Alternatively, it is also conceivable to adopt a sequential data transmission, in which case a so-called data bus is provided.
On the cylinder side, loops 20 assigned to the annular conduit 15 are provided, and these loops are connected to the actuator of the assigned switching valve 17 by a branch wiring 21. The loops 20 are in the form shown connected to the respective output units 19 of the control unit 18 via signal lines 22. When two lubricating holes arranged in a ring are arranged one above the other, two loops 20 connected to the same signal line 22 occur here. As a variant, each loop may be connected to a respective output 19 of the control device 18 via its own signal line. In the case of sequential data transmission, each cylinder or each loop or each switching valve may have its own data bus output. Advantageously, a configuration is provided in which a data bus output is assigned to each loop.

The total lubricant demand is determined first by the control unit 18 as a function of the load acting on the assigned engine. When the load is high, more lubricant demand occurs than when the load is low. The control device accordingly has an input 23 for a load-dependent signal, such as, for example, the torque acting on the crankshaft of the engine or the timing of the fuel injection which also depends on the load. This input unit 23 is connected via a signal line 24 to
Suitable sensor 25 for extracting load-dependent signals
Is connected to In addition to the load, of course, other parameters can also be considered. For example, special operating conditions, such as temperature in the area of the cylinder sliding surface, turning, braking, etc., can be taken into account. This is indicated in the embodiment shown by a further input 26 which is connected via a signal line 27 to a suitable sensor 28. The control device 18 has, in the example shown, a further input 29 for the fluid flow present in the region of the common rail 11. This input 29 is connected to the flow measuring device 13 via a signal line 30 for this purpose.

The control device 18 finally also has an input 31 for an assigned engine cycle-dependent signal, for example the engine crankshaft speed. The input 31 is connected via a signal line 32 to a suitable sensor 33 for extracting a signal for detecting an engine cycle. This signal is evaluated by the control unit 18 and the supply of the lubricant takes place in each case at a predetermined position of the piston 5. It is suitable to supply the lubricant such that the lubricant is discharged from the lubrication hole 10 when the piston ring package constituted by the piston ring 8 passes. However, it is not necessary to supply the lubricant every time the piston 5 strokes. If necessary, the fluid may be discharged every plural piston strokes.

Based on the parameters supplied via the inputs 23 to 26, the control unit 18 determines here parameters which are load-dependent and possibly temperature-dependent and / or operating-dependent. The total lubricant demand is determined using predetermined empirical values stored in the controller 18 as curves or tables. Based on this value, the control device 18 calculates the opening time and the opening frequency of the switching valve 17. The opening frequency can be varied in a stepwise manner, as has already been described, the interval between the phases being each one piston stroke. The determined total demand of the lubricant is compared with the current value of the fluid flow present in the common rail 11 applied to the input 20. If there is a difference, the opening time of the switching valve 17 and / or
Or the frequency is adapted accordingly.

The control unit 18 is expediently designed as a computer, that is to say as a computer having a main computer and a standby computer which automatically operates and assumes its role in the event that the main computer fails. This prevents failure of the lubrication device. An alarm can be issued when a danger is imminent, for example, when the lubricant temperature rises sharply. To this end, the control device 18 has an alarm output unit 34 connected to an alarm device 36 via a signal line 35. The alarm device may be configured to stop the engine if the alarm signal is not released after a predetermined time. The control device is also expediently configured such that manual intervention into the control process is possible.
To that end, the control device 18 comprises a communication device 37 which can include a display and a keyboard.

Although several embodiments according to the present invention have been described in detail, the present invention is not limited to these embodiments. One skilled in the art can adapt the general idea of the solution of the invention to the individual case.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a cylinder of a two-cycle large diesel engine.

FIG. 2 is a schematic diagram showing a lubricating device provided in a cylinder of a large two-cycle diesel engine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 5 Piston 9 Sliding surface 10 Lubricant discharge port 11 Common rail 12 Pump station 13 Flow measuring device 14 Individual pipeline 15 Annular pipeline 16 Supply pipeline 17 Switching valve (metering device) 18 Control device 19 Output unit 23, 25, 29, 31 Input unit 36 Alarm device 37 Communication device

Claims (14)

[Claims] An engine, in particular a two-stroke large diesel engine, comprising at least one cylinder (1)
And a piston (5) disposed therein, the piston being reciprocable along a sliding surface (9) of the cylinder (1), said sliding surface preferably comprising a cylinder The lubricant can be supplied through a lubricant discharge port (10) provided on the side and connected to an assigned supply pipe (16). A metering device (17) is assigned to the supply line (16) and is assigned to a supply line (16) of at least one group of lubricant outlets (10) and has a predetermined pressure. Common rail (1) containing lubricant
1) a control device (18) assigned to said metering device (17) and having at least one input (23, 26) for a measured value correlated with the lubricant demand;
In the engine provided with, the metering device, the lubricant discharge port (1
0), and the supply line (16) is selectively closed / closed by the switching valve.
The controller (18) is capable of opening, and the controller (18) obtains the required amount of the lubricant using the input measurement value in correlation with the lubricant demand, and based on the result, at least the switching valve ( An engine according to 17), wherein the switching valve is controlled correspondingly by deriving the opening time point and the closing time point. 2. The engine according to claim 1, wherein the control device also calculates the opening frequency of the switching valve and controls the switching valve accordingly. 3. The lubricant discharge ports of all the cylinders (1) are connected to the same common rail (11), and all of the switching valves (17) disposed in front of the lubricant discharge ports (10). 3) The engine according to claim 1 or 2, characterized in that said engine is controllable by said control device (18). 4. Individual conduits (14) respectively assigned to said cylinders (1) branch off from said common rail (11), which preferably passes through all said cylinders (1), Each of these individual lines is connected to at least one annular line (15), from which the lubricant discharge is preferably arranged at the same height and distributed over the cylinder circumference. 2. The supply line according to claim 1, wherein the supply line at the outlet is branched.
The engine according to any one of claims 1 to 3. 5. The control device (18) comprises an output (19) assigned to each of the cylinders (1), and the assigned cylinder (1) via these outputs.
5. The engine according to claim 1, wherein all of the switching valves (17) are controllable. 6. 6. The control device as claimed in claim 1, wherein the control device has at least one input for a load-dependent signal.
The engine described in the section. 7. The control device according to claim 1, wherein the control device has at least one input for cylinder temperature and / or lubricant temperature. The engine according to claim 1. 8. The method according to claim 1, wherein the control device has at least one input for operating state-dependent signals. engine. 9. The control device according to claim 1, wherein the control device has at least one input for an engine cycle-dependent signal. The engine described in. 10. The common rail (11) preferably comprises a flow measuring device (13) adjacent to the associated pump station (12), which has an input (29) of the control device. The engine according to claim 1, wherein the engine is assigned. 11. The control unit (18) determines a total lubricant demand using a measured value correlated with the lubricant demand applied to the input unit (23, 26), and calculates an entire lubricant demand. If there is a difference from the lubricant flow rate flowing through the common rail (11) applied to the switching valve (29), the switching valve (17)
The engine according to any one of claims 1 to 10, wherein the opening time and / or the opening frequency of the engine are adjusted. 12. The control device according to claim 1, wherein the control device is configured as a computer having a main control unit and a standby control unit that operates when the main control unit fails. An engine according to any one of the preceding claims. 13. The control device according to claim 1, wherein the control device has an output portion assigned to an alarm device. engine. 14. The control device (18) preferably comprises a communication device (3) with a display and / or keyboard.
14. The engine according to claim 1, wherein (7) is provided.