Bearing with bearing pin used in engine and other devices

Abstract

To provide an inexpensive bearing enabling simple design and bearing operation with excellent abrasion resistance.SOLUTION: The present invention relates to a bearing comprising a bearing shell 2 and bearing pins 1, 11, 12 with a rotational axis X, and the bearing pins 1, 11, 12 are arranged rotatably around the rotational axis X in the bearing shell 2. The bearing pins 1, 11, 12 comprises weakening points 3, which are asymmetric with respect to the rotational axis X, so that the bearing pins 1, 11, 12 are deformed by the action of external force F acting in the direction of the bearing shell 2. Therefore, the effective area of force between the bearing shell 2 and the bearing pins 1, 11, 12 can be increased via the deformation of the bearing pins 1, 11, 12.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a bearing with a bearing shell and a bearing pin according to the preamble of the independent claim. Furthermore, the present invention relates to a bearing pin according to the preamble of independent claim 13 for a bearing according to any one of claims 1 to 12, a crosshead according to independent claim 14 comprising a bearing according to any one of claims 1 to 12, and a large engine according to the preamble of independent claim 15 comprising a bearing according to any one of claims 1 to 12.

Background Art

[0002] In the prior art, many different types of bearings are known. Plain bearings are often used when a moving part slides on a workpiece fixed in a motor and a centrifugal pump.

[0003] Various bearings in combustion engines or other devices perform the task of fixing a rotating element or an oscillating element, or guiding them along a given path. Bearings are used to absorb and transmit forces between components that move relative to each other. In order to reduce mechanical losses and ensure a long service life, bearings are required for all of rotational motion, linear (sliding) motion, and pivotal motion. In particular, the bearing absorbs a radial force acting perpendicular to the axis of rotation and / or an axial force acting in the direction of the axis of rotation, and transmits these forces to other rotating or fixed elements. In modern combustion engines, in particular, plain bearings and rolling bearings are used.

[0004] Due to the prominent advantages of plain bearings, plain bearings have been (so far) almost exclusively used for crank drives. However, in order to reduce frictional losses, rolling bearings are used as long as the load conditions and installation conditions permit.

[0005] Using the plain bearing of a combustion engine, the shaft and the bearing are separated from each other by a load-bearing lubricating film, and metal contact is greatly prevented, and hydrodynamic lubrication conditions are targeted. Fluid friction guarantees low friction loss and a long service life due to the fact that it hardly wears. The rotational movement of the shaft in the bearing causes a flow in a viscous medium because the lubricant adheres to the surface of the sliding partner. When the wedge-shaped lubrication gap between the bearing surface and the eccentric pin narrows in the direction of movement, hydrodynamic pressure is generated in the lubricating film to prevent the lubricant from flowing out sideways due to its viscosity. This pressure tries to push apart the surfaces that limit the lubricating film, thereby generating a load capacity (wedge pressure) that balances the external shaft force.

[0006] The bearing shell may be configured as a half-shell or a bearing bush. Depending on the construction mode, either type is used. They mainly depend on the design of the bearing block and the shaft.

[0007] In the prior art, thin-walled bearing shells (thin-walled bearing shells, thickness / diameter ratio > 0.05) are known, and they are installed with preload to ensure good contact of the shell in the housing. This also provides good protection against torsion during operation. Dispersion and protrusion are used to ensure the necessary pressing force.

[0008] The various possible bearing shapes depend on the control of the dynamic behavior of the forces acting on the bearing. Specifically, the vibration behavior of a sliding bearing substantially depends on the mass of the rotor, the mass distribution, the bending stiffness of the shaft and the suspension, and the damping characteristics of the bearing under given load conditions. Lateral vibration (forced self-excited vibration) can be prevented or optimized by a suitable configuration of the bearing. The selection of the bearing shape and the configuration of the bearing is an important part of the optimization. Because different bearing shapes and configurations of the bearing also have different characteristics.

[0009] To prevent sliding friction, the clearance of the bearing, to which a liquid or a stable (greasy) lubricant is generally supplied, is created by the suitable manufacturing dimensions of the movable and fixed functional parts and their common adjustment. Due to this bearing clearance, a load-bearing lubricating wedge can be formed from the lubricant in the available space with a sufficient circumferential speed of the bearing pin. The lubricating wedge separates the sliding parts so that the bearing operates with maximum lubrication. This process is common for hydrodynamic plain bearings.

[0010] During operation, a lubricant supply element for continuously supplying a lubricant such as lubricating oil is often required to supply sufficient lubricant to the bearing and, if necessary, to maintain the sliding layer of the bearing.

[0011] For example, in small connecting rod eyes and piston pin eyes, thin-walled multi-material bushings (synthetic materials) are often used for the bearings of camshafts, rocker arms, drag levers, gear wheels, and oil pump shafts, as well as water pump shafts. Such bushings can be manufactured by rolling with butt joints or by a centrifugal casting process in steel pipes.

[0012] The pin is an extension of a component (often cylindrical or cuboid) and serves to connect the component to another component. In a radial plain bearing, the movable part is often the pin of the shaft or shaft, and the fixed part is generally the bearing shell.

[0013] On the one hand, the bearing enables the rotation of the shaft and, at the same time, transmits the axial force to the surrounding structure with as little deformation as possible. In modern gearboxes, the allowable load and rigidity of the axial load are very high, so that only high-quality and optimized bearings meet the requirements. At the same time, due to the axial force and the pressure of these bearings, proper installation is very important.

[0014] The simplest and most cost-effective possibility is the bearing pin. The bearing pin is significantly smaller compared to the nominal diameter of the bearing shell. In the best case, the surface area of the bearing shell is already sufficient to absorb the forces of the bearing with an acceptable surface load.

[0015] In mechanical engineering, a pin is a stepped end of a shaft. The pin can be adapted to a bearing and serves as the center of rotational movement. Such pins are often produced by turning an unprocessed shaft, and many of their dimensions are standardized. On the other hand, at the end of a shaft, the pin is not adapted to a bearing but can be adapted to a shaft-hub connection such as a feather key. The grooves required for this are rolled into a pre-machined pin. The extension, width, and depth of the grooves are standardized like the related pins.

[0016] The crankpin is located outside the center of the shaft. The crankpin is adapted to a connecting rod or a driving rod, thereby ensuring the drive of the crank. In a locomotive, the coupling rod is also connected to the corresponding two wheel sets.

[0017] In the case of an engine with a crosshead, the crosshead absorbs the forces acting in the vertical and lateral directions on the crankshaft (crankpin). It keeps the piston from receiving lateral forces. As a result, the piston can be made quite flat (disc piston), and there is little stress on the hot cylinder and the running surface of the piston. In the case of a plunger-piston machine, the piston shroud takes on the role of the crosshead and transmits the lateral forces to the cylinder.

[0018] The kinematics of a crank drive with a crosshead is substantially the same as that of a crank drive without a crosshead.

[0019] The crosshead is mainly used in reciprocating internal combustion engines, more specifically in large two-stroke diesel engines and reciprocating steam engines.

[0020] For example, for generating electrical energy, a large crosshead-type diesel engine, preferably used in the shipbuilding industry or in stationary plants, comprises three large housing segments which form the engine frame. Lateral to the bearing saddles with the main bearings of the crankshaft, on a base plate having a transverse support element for receiving the crankshaft, a so-called stand is arranged spaced apart from the base plate. Depending on the number of cylinders of the large diesel engine, this stand comprises several supports arranged opposite one another, each of which has a vertical sliding surface for guiding two adjacent crossheads connected to the crankshaft by push rods. In each case, the two opposing vertical sliding surfaces are additionally supported by a central wall. Generally, the individual supports are connected to one another by a common cover plate. The cylinder section, often also called the cylinder jacket, is then arranged on the stand of the cover plate. The cylinder section is suitable for accommodating several cylinder liners. The base plate, the stand, and the cylinder section are connected to one another by tie rods. The tie rods extend standardly inside the supports in the region of the stand by being screwed into or onto the base plate under a considerable preload.

[0021] The crosshead is a mechanical element used in crank drives. The crosshead couples the reciprocating piston rod to the connecting rod of the reciprocating and rotary motion. The crosshead is mainly found in large piston machines. The axis of the piston rod and the axis of the connecting rod pin intersect on the same plane. The crosshead has separate plain bearings and is rigidly connected to the piston rod and the piston. The connecting rod oscillates around the crosshead and is connected to the crankshaft.

[0022] The connecting rod creates the connection and thus the force closure between the piston and the crankshaft. The connecting rod converts the straight up-and-down motion of the piston into the circular motion of the crankshaft and is thus subject to tension, compression, bending, and buckling.

[0023] Generally, the connecting rod is supported by the crankpin of the crankshaft by means of a plain bearing. The bearing cover of the connecting rod is fastened to the leg portion of the connecting rod by an expanding screw. In many cases, the connecting rod is designed with a hollow drilled or a cast oil channel to supply lubricant to the piston pin.

[0024] In order to ensure that the connecting rod is lightweight and has high strength, it is generally made from the following materials, namely microalloyed steel, sintered metal, high-quality aluminum, carbon fiber reinforced plastic (CFRP), and titanium (for high-performance engines). A large series of connecting rods are forged, cast, or sintered. Forged connecting rods are less costly and have a better strength-to-weight ratio than sintered connecting rods. However, die production is relatively expensive.

[0025] Normally, the bearing pin of the crankshaft is positioned in the cylinder-side portion of the crankcase in a bearing half-shell formed in the bearing web. Subsequently, a bearing cover, or preferably a similar one formed in an intermediate cover called a so-called bed plate, is screwed onto the bearing half-shell. A second part of the crankcase or crankcase cover is arranged on the cylinder-side part and screwed thereto, and the bearing shell is fixed by means of mounting, etc.

[0026] It should also be noted that it is also possible to have bearing shells for two parts. Using these, half is positioned and fastened to the crankcase before the crankshaft is installed, and after the crankshaft is inserted, the second part is adjusted together with the bearing cover.

[0027] The connecting rod connected to the crankshaft via the bearing of the connecting rod is usually hingedly attached to the piston. The crankshaft can also have two crankshaft bearing pins (crank pins), and a bearing pin of the connecting rod formed at a distance radially from the axis of rotation, with the connecting rod disposed thereon. The bearing pins of the connecting rod are connected to the bearing pins of the crankshaft and are typically disposed between the cheeks of the two crankshafts, each having the mass of the flywheel.

[0028] A disadvantage of bearings known in the prior art is, among other things, the problem of friction. In the case of bearings, generally the aim is to achieve hydrodynamic lubrication conditions where the components are separated by a load-bearing lubricating film and metal contact is largely prevented. However, when an external force acting in the direction of the bearing shell acts on the bearing, an effective area of the force is created between the components of the bearing (i.e., between the bearing shell and the bearing pin). This effective area of the force can be very small (due to the outer shapes of the bearing shell and the bearing pin), whereby very high pressures with very high friction affect this small effective area or contact area of the force. In addition, the limited load capacity of bearings known in the prior art is a major disadvantage. As long as a load is accurately applied to the (hydrodynamic) bearing, the bearing shell is protected by an oil film / lubricating film that does not cause mixed friction. In this regard, the bearing material (e.g., white metal) can safely absorb the pressure transmitted by the oil / lubricant. However, as the load increases, the oil pressure / lubrication pressure increases overall, and the bearing material ultimately reaches its strength limit. At the same time (or somewhat earlier or somewhat later), mixed friction (the friction that occurs between two sliding surfaces when there is insufficient lubricant) will occur, which can cause further significant damage.

[0029] The influence of friction results in significant wear, which in particular leads to malfunctions in the entire device (such as a motor, etc.), thereby requiring expensive repairs to replace the bearing. This not only results in unnecessary costs but also, of course, places a significant burden on the environment. SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

[0030] Therefore, an object of the present invention is to prevent the adverse effects known in the prior art. Specifically, an object of the present invention is to provide a low-cost bearing that enables a simple design and better wear-resistant bearing operation. Accordingly, a bearing that additionally exhibits a long service life compared to bearings known in the prior art will be provided.

Means for Solving the Problems

[0031] The object is achieved by a bearing having a bearing shell and a bearing pin according to the preamble of independent claim 1, a bearing pin according to the preamble of independent claim 13 for a bearing according to any one of claims 1 to 12, a crosshead according to the preamble of independent claim 14 comprising a bearing according to any one of claims 1 to 12, and a large diesel engine according to the preamble of independent claim 15 comprising a bearing according to any one of claims 1 to 12.

[0032] According to the present invention, a bearing is proposed that includes a bearing shell and a bearing pin with a rotating shaft. The bearing pin is rotatably arranged around the rotating shaft in the bearing shell. The bearing pin of the bearing according to the present invention has a weakened portion asymmetric with respect to the rotating shaft so that the bearing pin is deformed by the action of an external force acting in the direction of the bearing shell, whereby the effective area of the force between the bearing shell and the bearing pin is increased through the deformation of the bearing pin. By increasing the effective area of the force, the oil pressure / lubrication pressure of the bearing, specifically the maximum oil pressure / lubrication pressure of the bearing, can be reduced. This is because the contact surface (specifically, the effective surface of the force) between the bearing shell and the bearing pin increases, whereby the force acting between the bearing shell and the bearing pin is better dispersed.

[0033] Within the framework of the present invention, the effective area of the force between the bearing shell and the bearing pin means the area where pressure or force is transmitted from the bearing pin to the bearing shell under the action of an external force on the bearing. The pressure, specifically, the optimum lubrication pressure between the bearing pin and the bearing shell for a particular application and / or applied force, can be reduced so that the optimum lubrication conditions (for the particular application and / or acting force) do not exist in a particular part between the bearing and the bearing shell. Specifically, the optimum lubrication pressure may be a hydrodynamic lubrication pressure, and thus the hydrodynamic lubrication conditions no longer exist due to the reduction of the pressure between the bearing pin and the bearing shell. This particular part where the optimum lubrication conditions for the applied and acting force between the bearing and the bearing shell no longer exist is the effective area of the force, where most of the external force acting in the direction of the bearing shell is transmitted between the bearing pin and the bearing shell. In a bearing according to the prior art, when the lubricating layer decreases (or disappears completely), a non-optimum, i.e., too thin (or non-existent) lubricant film remains on the effective surface of the force and between the bearing and the bearing shell, thereby causing the influence of strong friction and corresponding wear. Therefore, a minimum lubricating layer exists in the effective area of the force, where in particular the hydrodynamic lubrication conditions no longer exist. The effective area of the force can also correspond to the direct contact area between the bearing pin and the bearing shell, but this occurs only in the standard bearing operation under special load conditions. As already described, the bearing pin is deformed by the action of an external force acting in the direction of the bearing shell. Here, the bearing pin is deformed by the pressure on the effective area of the force between the bearing pin and the bearing shell, whereby the effective area of the force between the bearing pin and the bearing shell is increased by the deformation process of the bearing pin. Due to this deformation-induced increase in the effective area of the force according to the present invention between the bearing pin and the bearing shell, a greater, and thus the optimum thickness of the lubricant for the applied and acting force, specifically the minimum required thickness of the lubricant (especially without hydrodynamic lubrication conditions) becomes possible, whereby the friction between the bearing pin and the bearing shell is reduced by the action of the external force acting in the direction of the bearing shell.However, in the prior art, since the effective area of the force is very small, the friction due to the corresponding insufficient thickness of the lubricating layer is also very high, resulting in significant wear to be prevented.

[0034] When an external force acting in the direction of the bearing shell acts on the bearing pin in the bearing of the present invention, the effective area of the force is created between the bearing pin and the bearing shell, similar to the case of a bearing known in the prior art. This can mean that the surfaces of the bearing shell and the bearing pin are in contact with each other without a (sufficient) lubricating film separating the bearing shell and the bearing pin.

[0035] However, the bearing pin according to the present invention has a weakened portion that is asymmetric with respect to the rotation axis. Therefore, the asymmetric weakened portion of the bearing pin is not symmetrically arranged around the rotation axis. When the example of a cylindrical bearing pin is used to explain the asymmetric weakened portion, the asymmetric weakened portion should have a circular cross-sectional area, and thus the center of the circular cross-sectional area of this asymmetric weakened portion does not lie on the rotation axis. However, in the case of a symmetric weakened portion, the circular cross-sectional area of this symmetric weakened portion lies on the rotation axis.

[0036] Due to this asymmetric weakened portion, the bearing pin is deformed by the action of an external force acting in the direction of the bearing shell. Therefore, the effective area of the force between the bearing shell and the bearing pin is increased. This is because when the force is applied to the bearing pin, the bearing pin is deformed in the direction of the bearing shell by the pressure generated between the bearing shell and the bearing pin. Specifically, the bearing pin is deformed asymmetrically. This is because the weakened portion of the bearing pin is preferably centered on the side of the bearing pin, where the pressure acts directly on the surface of the pin by the external force acting in the direction of the bearing shell. The specific load is reduced by increasing the contact surface between the bearing pin and the bearing shell because the contact surface of the bearing pin is increased.

[0037] Therefore, the bearing pin deforms relying on the design of the asymmetric weakening location. The asymmetric weakening location of the bearing pin is adapted according to the direction in which an external force acting in the direction of the bearing shell occurs and the point. Therefore, the type, size, and shape of the asymmetric weakening location are determined by the applied and acting forces.

[0038] The advantage of the device according to the invention is, inter alia, that the pressure and thus the friction are reduced by the increased force area. This reduces the wear of the bearing. This is because the bearing according to the invention is more effective and cost-efficient than bearing devices known in the prior art and devices having bearings. By increasing the effective area of the force, the surface pressure is better distributed, whereby the same force is distributed over a larger area. This also ensures better lubrication, i.e., optimal lubrication of the bearing according to the invention, and extends the service life of the bearing. When the bearing is soiled by contaminating particles, in particular when the thickness of the lubricating film is small and the contaminating particles are larger than the thickness of the lubricating film, damage may occur. However, the better distribution of the surface pressure enables a larger thickness of the lubricating film, thereby also preventing possible damage to the bearing by the soiled particles.

[0039] As described above, the bearing pin according to the invention can be designed as a cylindrical bearing pin. In the case of a cylindrical bearing pin, preferably the axis of rotation corresponds to the symmetric n-fold axis of rotation of the cylindrical bearing pin (i.e., the axis of rotation about which the cylinder is rotationally symmetric regardless of the angle of rotation). The asymmetric weakening location is asymmetric with respect to the symmetric n-fold axis of rotation of the cylindrical bearing pin. Therefore, the cylindrical bearing pin can be configured as a certain kind of hollow cylinder with a cavity, and this cavity is not centered (with respect to the round base or cross-sectional area) at the center of the cylindrical bearing pin.

[0040] As described above, relying on the design of the bearing, the axis of rotation of the bearing pin can correspond to the axis of symmetry of the bearing pin, whereby the bearing pin is rotationally symmetrically arranged so as to be rotatable around the axis of symmetry of the bearing shell.

[0041] However, the bearing pin does not need to be a symmetric body. In particular, the bearing pin can be designed as an n-sided body with rounded corners and edges. The bearing pin can also be configured as spherical or elliptical. In particular, the elliptical body is already deformed under a slightly applied load, so that the effective area of the force between the bearing pin and the bearing shell is increased. In order to eliminate the need for overly strong (pronounced) asymmetric weakening points and to increase the influence of the effective area of the force between the bearing pin and the bearing shell without weakening the bearing pin so that it is broken by excessive forces that would break the bearing pin, the bearing pin can be pre-designed as elliptical. In this case, however, the bearing shell preferably has a curvature adapted to the ellipse.

[0042] In one embodiment of the present invention, the bearing pin may have symmetric or asymmetric weakening points with respect to an axis of a first section that intersects orthogonally to the rotation axis of the bearing pin. For example, when considering the cross-sectional area of the bearing pin (orthogonal to the rotation axis), the axis of the first section can follow (or be parallel to) this cross-sectional area of the bearing pin. Thus, the asymmetric weakening point is symmetric if it is a point mirrored symmetrically with respect to the axis of the first section. Depending on the applied force, the weakening point may of course be asymmetric with respect to the axis of the first section, so that, for example, there are two weakening points of different degrees on each side of the axis of the first section.

[0043] Thus, the symmetric or asymmetric weakening point is a weakening point that is symmetric with respect to the axis of the first section and asymmetric with respect to the rotation axis of the bearing pin.

[0044] In practice, the bearing pin of the bearing of the present invention can include symmetric weakening points that are symmetric with respect to an axis of a second section that intersects orthogonally to the symmetry axis of the bearing pin.

[0045] The bearing according to the invention can be provided with a force element. In practice, this force element can be arranged on the bearing pin such that a force acts on the bearing pin in a pre-determinable direction via the force element. In this case, the force element can be designed as a force rod, a piston rod, or a push rod. When the bearing according to the invention is attached to an engine, such as a large diesel engine, for example, the force element can in particular be the connecting rod of the engine, whereby the bearing can be arranged on the crosshead or the crankshaft.

[0046] The asymmetric weakening point of the bearing pin can be designed as an asymmetric recess, in particular as a perforation. Due to the asymmetric weakening point, the bearing pin can be a hollow body (with a weakening point along the axis of rotation over the entire extension of the bearing pin body), or can have a weakening point in the form of a cavity.

[0047] Depending on the application of the bearing, the bearing pin can be a crosshead pin or a crankpin.

[0048] In one embodiment of the invention, the asymmetric weakening point of the bearing pin can be designed in a form in which the material type changes, and / or the material density changes, and / or the material structure changes. Thus, at the point where the asymmetric weakening point of the bearing pin is present, there will be a changed material. For this purpose, the material at this point can be more flexible, or can have a lower density, or the material can differ from the surrounding material in some other way. This is particularly recommended when the bearing pin is designed as a composite material or an alloy. Accordingly, at the point of the asymmetric weakening point, the bearing pin will have a different material composition. When the bearing pin is made of steel, the point of the asymmetric weakening point of the bearing pin will thus contain little carbon, nickel, or similar additives, or will contain a further different additive that weakens the material at the corresponding point.

[0049] In practice, the bearing pin can have a plurality of asymmetric weakening points with respect to the rotation axis, whereby the bearing pin can be appropriately deformed even under the influence of complex forces. For example, two (or more) asymmetric weakening points of the same degree may exist, and the asymmetric weakening points may have different degrees or different outer shapes. One or more asymmetric weakening points may extend along the entire extension of the body along the rotation axis, or may extend as a cavity along only one section along the extension of the bearing pin body along the rotation axis.

[0050] Normally, a force, specifically an axial force up to about 10,000 kN, can act on the bearing of the large diesel engine according to the present invention. In this case, the optimum lubrication pressure, specifically the hydrodynamic pressure, can be up to 600 bar. In this case, the minimum thickness of the optimum lubricating film is 5 to 30 micrometers, specifically 5 to 25 micrometers, particularly 15 to 25 micrometers.

[0051] Of course, the acting force and the oil film pressure are dependent on each other, and therefore the thickness of the oil film also depends on the dimensions of the components and the relative speed of the movable parts.

[0052] Depending on the complexity of the acting force, it may be necessary to create a complex weakening structure in the bearing pin according to the present invention. For this purpose, the bearing pin can be designed as two parts, where the bearing pin comprises a bearing pin ring and a bearing pin core. In this regard, the bearing pin ring can be a hollow body, and the bearing pin core can be arranged in the bearing pin ring in an incorporated structure (for example, rolling). This has the great advantage that a complex structure can be easily incorporated into the bearing pin core, whereby the bearing pin core can then be inserted into the bearing pin ring by pressing or the like.

[0053] The bearing according to the present invention can be designed as a bearing particularly suitable for a large diesel engine, specifically a bearing of a large diesel engine with a crosshead, and accordingly the bearing pin is designed.

[0054] According to the present invention, there is further proposed a bearing pin of a bearing according to the present invention, which has an asymmetric weakening portion so as to be deformable by a force by a pre-determinable method. That is, it depends on the asymmetric weakening portion and its own force, and the corresponding deformation of the bearing pin continues.

[0055] According to the present invention, there is further proposed a crosshead with a bearing according to the present invention, which includes a bearing shell and a bearing pin with a rotating shaft, and the bearing pin is rotatably arranged around the rotating shaft in the bearing shell. The bearing pin of the bearing according to the present invention has an asymmetric weakening portion with respect to the rotating shaft so that the bearing pin is deformed by the action of an external force acting in the direction of the bearing shell. Thereby, when a force is applied to the bearing pin, the effective area of the force between the bearing shell and the bearing pin is increased by the deformation of the bearing pin. The crosshead can be designed in particular for large engines, especially two-stroke large diesel engines.

[0056] According to the present invention, there is further proposed a large diesel engine, in particular a large diesel engine of a crosshead. The large diesel engine includes a bearing according to the present invention having a bearing shell and a bearing pin with a rotating shaft, and the bearing pin is rotatably arranged around the rotating shaft in the bearing shell. The bearing pin of the bearing according to the present invention has an asymmetric weakening portion with respect to the rotating shaft so that the bearing pin is deformed by the action of an external force acting in the direction of the bearing shell. Thereby, when a force is applied to the bearing pin, the effective area of the force between the bearing shell and the bearing pin is increased by the deformation of the bearing pin.

[0057] In this regard, a preferred important embodiment will be described. In the preferred embodiment, the bearing according to the present invention in the large diesel engine of the crosshead is arranged in the crosshead. The bearing pin is a cylindrical bearing pin having an asymmetric weakening portion with respect to the rotating shaft of the bearing pin, but is symmetric with respect to the axis of the first section, so it is a symmetric asymmetric weakening portion.

[0058] Hereinafter, the present invention and the prior art will be described in more detail based on examples with reference to the drawings.

Brief Description of the Drawings

[0059]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0060] Figure 1 is a schematic diagram of the prior art. A bearing already known in the prior art is shown. Here, the bearing includes a bearing shell 2' and a bearing pin 1' rotatably disposed in the bearing shell 2'. The intersection point of the two section lines S' is the rotation axis of the bearing pin. In the prior art, there is an asymmetric weakening portion 3', which is symmetrically disposed around the rotation axis exactly at the center of the bearing pin. Here, the asymmetric weakening portion 3' is a recess and a certain kind of hollow cylinder. In the prior art, a force F' acts on the bearing pin 1', and thereby this force is transmitted from the bearing pin 1' to the bearing shell 2'. However, the bearing pin 1' known in the prior art does not deform so that the effective area of the force between the bearing pin 1' and the bearing shell 2' increases and the pressure between the bearing pin 1' and the bearing shell 2' decreases, so the effective area of the force between the bearing pin 1' and the bearing shell 2' is very small. However, the recess 3' known in the prior art only serves to reduce the mass of the pin or return the oil.

[0061] Figure 2 is a schematic cross-sectional view of a bearing according to the present invention in different embodiments. Here, all embodiments A to J include a bearing shell 2 and a bearing pin 1, and the bearing pin 1 is configured as a cylindrical bearing pin. The rotation axis X of the bearing pin 1 is located at the intersection point of the section axis S. A to C, E, F, G, and J in Figure 2 show a bearing pin having a single asymmetric weakening portion 3, while D, H, and I in Figure 2 show two asymmetric weakening portions 31 and 32. These asymmetric weakening portions 31 and 32 may have the same or different shapes. The bearing pins according to D, H, and I are particularly suitable when two different forces F1 and F2 that can act simultaneously or alternately act on the bearing. B, C, D, E, G, and J in Figure 2 are particularly suitable for the force F acting on the bearing 1 as shown. This is because the bearing pin 1 has an asymmetric weakening portion at the direct contact surface between the bearing shell 2 and the bearing pin 1, whereby the bearing pin 1 deforms at the direct contact surface between the bearing pin 1 and the bearing shell 2. J in Figure 2 shows a bearing pin configured as two parts of a bearing pin, comprising a bearing pin ring 102 and a bearing pin core 101. The bearing pin core 101 is arranged inside the bearing pin ring 102. Comparing Figure 1 with Figure 2, it can be easily understood that the effective force area of the bearing device according to the present invention is larger than that of the bearing in the prior art, and therefore the friction of the bearing according to the present invention is also significantly reduced.

[0062] Figure 3 is a schematic view of the crosshead. Here, the crosshead 6 is shown in detail, and the crosshead pin 12 is configured as a bearing pin according to the present invention with a bearing according to the present invention. The sliding shoes 61 of the four crossheads guide the crosshead 6, and thus the piston rod 21, in a straight line on the sliding path of the rail 62 or on a path parallel to the direction of the rail 62. With the crosshead provided with the sliding shoes 61 of the crosshead, the force F acts on the crosshead pin 12 only from one direction via the piston rod 21. Here, the force F mainly acts orthogonally to the crosshead pin 12. Since the force F acts only from one direction (orthogonal to the rotation axis X) from above, the asymmetric weakening points according to B, E, or J in FIG. 2 are particularly suitable for the crosshead. Because when the bearing pin 1 is aligned with the asymmetric weakening point in the direction of the propulsion rod 22, the cross-head pin 12 is deformed in the bearing shell by the action of the force F, thereby increasing the effective area of the force between the bearing pin 1 and the bearing shell, and the acting force F is dispersed over a large area of the bearing, so that the pressure is well dispersed on the direct contact surface.

[0063] Figure 4 is a schematic view of a partial cross-section of a large engine 100, in particular a diesel engine, especially a two-stroke large diesel engine. The large engine 100, in particular a large diesel engine, especially a two-stroke large diesel engine, operates on the principle of a two-stroke with longitudinal scavenging. The large engine 100 includes a plurality of cylinders 111 in a cylinder chamber 112 separated from the engine room 113. Power is transmitted from a piston 114 that moves up and down in the cylinder 111, and this power is finally guided to the crankshaft 200 of the engine via the piston rod 21, the crosshead pin 12 of the crosshead 6, the propulsion rod 22, and the crank. The crosshead 6 is guided by guiding elements on a straight sliding path, that is, by the sliding shoes 61 and the rail 62. As already explained in FIG. 3, the crosshead pin 12 is designed as a bearing pin according to the present invention with a bearing according to the present invention.

[0064] Figure 5 is a schematic view of a large engine 100, specifically a large diesel engine, particularly a two-stroke large diesel engine, having a connecting rod (propelling rod) 22. The connecting rod 22 includes a first end 4 with a bearing shell 2 for connection to the crosshead 6 and a second end 7 with a second perforation 8 for connection to the crankpin 11. The connecting rod 22 further includes a bar section 10 between the first end 4 and the second end 7. During the transmission of force from one component to another, high friction may occur in the bearing. This is because the pressure generated by the transmission of force pushes the lubricant away from the transmission point, resulting in direct contact between the bearing shell 2 and the bearing pins 11 and 12. Specifically, during the transmission of force between the connecting rod 22 and the crankpin 11, a large force presses between the bearing shell 2 and the crankpin 11. In particular, it is important to relieve the load on the bearing between the connecting rod and the crankpin / crosshead by a continuous supply of lubricant. When dispersing the pressure over a large surface area, due to the deformation of the bearing pins 11 and 12, the pressure is better dispersed, and thereby the lubricant can also be more easily introduced into the bearing. In this embodiment, the bearing according to the present invention is composed of a bearing shell 2 and asymmetric bearing pins as the crankpin 11 and the crosshead pin 12. In principle, especially the crankpin 11 and / or the crosshead pin 12, and thus the respective bearings, can be designed like the bearing according to the present invention.

Explanation of Reference Numerals

[0065] 1 Bearing pin 1’ Bearing pin 2 Bearing shell 2’ Bearing shell 3 Weakening point 3’ Weakening point 4 First end 6 Crosshead 7 Second end 10 Bar section 11 Crankpin 12 Crosshead pin 21 Piston rod 22 Propelling rod 31 Weakened part 32 Weakened part 61 Sliding shoe 62 Rail 100 Large engine 101 Bearing pin core 102 Bearing pin ring 111 Cylinder 112 Cylinder chamber 114 Piston Force F Force F’ Force F1 Force F2 Section line S, section axis Section line S’, section axis

Claims

1. A bearing comprising a bearing shell (2) and a bearing pin (1, 11, 12) having a rotating shaft (X), wherein the bearing pin (1, 11, 12) is rotatably arranged around the rotating shaft (X) in the bearing shell (2), the bearing pin (1, 11, 12) is provided with a weakened portion (3) asymmetric with respect to the rotating shaft (X) so as to be deformable by the action of an external force (F) acting in the direction of the bearing shell (2) on the bearing pin (1, 11, 12), whereby the effective area of the force between the bearing shell (2) and the bearing pin (1, 11, 12) can be increased through the deformation of the bearing pin (1, 11, 12). A bearing characterized by this.

2. The bearing according to claim 1, wherein the bearing pin (1, 11, 12) is a cylindrical bearing pin (1, 11, 12).

3. The rotating shaft (X) of the bearing pin (1, 11, 12) is the axis of symmetry of the bearing pin (1, 11, 12), whereby the bearing pin (1, 11, 12) is rotatably arranged symmetrically around the axis of symmetry in the bearing shell (2). The bearing according to claim 1 or 2.

4. The bearing pin (1, 11, 12) is provided with an asymmetric weakened portion that is symmetric with respect to an axis (S) of a first section that intersects orthogonally with the rotating shaft (X) of the bearing pin (1, 11, 12). The bearing according to any one of claims 1 to 3.

5. The bearing according to claim 3, wherein the bearing pin is provided with an asymmetric weakened portion that is symmetric with respect to an axis of a second section that intersects orthogonally with the axis of symmetry of the bearing pin.

6. The bearing comprises a force element, specifically a force rod, a piston rod (21), or a propulsion rod (22), and the force element is arranged on the bearing pin (1, 11, 12) such that the force (F) can be introduced onto the bearing pin (1, 11, 12) in a pre-determinable direction through the force element. The bearing according to any one of claims 1 to 5.

7. The asymmetric weakened portion (3) of the bearing pin (1, 11, 12) is an asymmetric recess, specifically a perforation. The bearing according to any one of claims 1 to 6.

8. The bearing pin (1, 11, 12) is a crosshead pin (12) or a crank pin (11). The bearing according to any one of claims 1 to 7.

9. The asymmetric weakening portion (3) of the bearing pins (1, 11, 12) is configured in a form in which the material type changes, and / or in a form in which the material density changes, and / or in a form in which the material structure changes, the bearing according to any one of claims 1 to 8.

10. The bearing pins (1, 11, 12) include a plurality of asymmetric weakening portions (3) with respect to the rotating shaft (X), the bearing according to any one of claims 1 to 9.

11. The bearing pins (1, 11, 12) are bearing pins (1, 11, 12) of two parts including a bearing pin ring (102) and a bearing pin core (101), and the bearing pin core (101) is arranged inside the bearing pin ring (102), the bearing according to any one of claims 1 to 10.

12. The bearing pins (1, 11, 12) are configured as bearing pins (1, 11, 12) for a large engine (100), specifically as bearing pins (1, 11, 12) for a large crosshead diesel engine, the bearing according to any one of claims 1 to 11.

13. A bearing pin (1, 11, 12) according to any one of claims 1 to 12, wherein the bearing pin (1, 11, 12) is characterized by including an asymmetric weakening portion (3) such that the bearing pin (1, 11, 12) is deformable by a force (F), the bearing pin (1, 11, 12).

14. A crosshead for a large engine, specifically a two-stroke large diesel engine, comprising the bearing according to any one of claims 1 to 12.

15. A large engine, specifically a large diesel engine, particularly a large crosshead diesel engine, comprising the bearing according to any one of claims 1 to 12.

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