RU209061U1 - Internal combustion engine - Google Patents

Abstract

The utility model relates to mechanical engineering and can be used in reciprocating machines, namely in internal combustion engines with removable cylinder liners. An internal combustion engine (ICE) contains a cylinder block, a cylinder head, cylinder liners placed in block bores. The removable cylinder liner creates a closed gas joint with the upper collar, through which it is clamped by loading the collar of the upper end of the liner with large tightening forces for the bolts of the cylinder head to the block. Studies have shown that after the assembly of the internal combustion engine, the sleeves have deformations along and along the circumference of the working surface. Deviations of macrogeometry from the correct cylindrical shape of the working surface of the sleeve are expressed in waviness along the circumference and along the axis. In this case, the working surfaces of the piston rings of the correct round shape are in contact and rest on the surface of the sleeve in separate areas. Distortion of the macrogeometry of the sleeves have all the assembled internal combustion engines with removable sleeves. In the internal combustion engine of the present utility model, conditions are created for compensating for deviations of removable sleeves. The inner working surface, machined to the final size, is covered with a soft running-in layer of brass 0.02-0.03 mm thick.

Description

Technical field

The utility model relates to the field of mechanical engineering for the production of diesel engines for automobile and specialized vehicles, as well as to the operation of internal combustion engines (ICE) of such complex high-tech equipment as cars, transport, transport-technological machines and complexes (TTMiK), including, agricultural, construction, road, loading and unloading vehicles, special vehicles and armored vehicles. An important condition is to reduce the cost of maintenance, repair and operation, achieved by improving the reliability of the internal combustion engines of cars and TTMiK. But despite this, in the operation of TTMiK for their intended purpose, there are deviations and inconsistencies in the dimensions of parts and assemblies, their wear, change in shape, violations of the interaction of parts in joints, in systems and mechanisms of internal combustion engines, including changes in gaps, tightness and fit, which, according to In the course of study and research, they are eliminated by various constructive and technological measures for improvement.

State of the art

The utility model is aimed at fulfilling the task of using the assigned resource of the internal combustion engine, preventing emergency failures by means of constructive and technological improvements based on research at the stage of fine-tuning in the production of the product. Manufacturers research and improve the design of internal combustion engines and their systems, improve production quality, ensure the reliability and service life of engines and their mechanisms and systems throughout the entire product life cycle.

Prerequisites for creating a utility model

Internal combustion engines (ICE) [1], in which there is a gas joint to connect the cylinder block to the block head, removable cylinder liners are installed with a seat belt in the block bore and are supported by shoulders in the block and cylinder head. With the help of bolts or anchor studs, the block head, sleeve and engine block are connected and form a single internal combustion engine assembly, and the gas joint is provided by tightening the bolts. This design has a number of significant drawbacks, since to ensure reliable operation, anchor ties tightening forces are required that significantly exceed the forces from gas forces in the ICE cylinder during a flash.

This necessitates the use of anchor bolts or studs of increased rigidity, leads to overloading of the block or crankcase parts in the places where the studs are embedded, to deformation of the seat and support collars of liners, block heads, distortion of the geometry of the working surface of the cylinder liners, especially in light forced diesel engines [2 ]. Deviations from the cylindricity of the manufactured sleeve after installation reach ± 20-30 microns. Sleeve deformations lead to non-cylindrical and non-circular working surface, incomplete contact of the working surface of the rings with the sleeve, gas breakthrough through leaks in places of oversized diameter, burns and scoring in places of underestimated diameter of the inner surface of the sleeve (figure 1), which leads to engine failures. Significant bolt tightening forces, which create a "joint margin" in such ICE designs, do not allow significant forcing of the engine in terms of maximum combustion pressures in the cylinder.

Patent Documents

The closest solution explaining the technical essence of the claimed design problem of the internal combustion engine is the solution according to patent No. 2168045MPK F02F1 / 00, F04B39 / 12 [3], in which the sleeve is unloaded. Reliable sealing in the internal combustion engine, consisting of a cylinder block and docked with it using anchor bolts wrapped in a block, cylinder heads placed in the bores of a block of cylinder liners with an "unloaded" gas joint is achieved by the fact that the load from the bolts through the head is transferred to the block, the sleeve does not participate in the transfer of forces from the gas joint, but is pressed against the head with its bolts with less effort, due to which the deformation of the sleeve from tightening the gas joint is reduced. To do this, a base plate is installed in the lower part, which presses the sleeve through its lower end with the help of bolts screwed into the head and located in the through holes of the cylinder block. Such designs are technologically very complex, have a high labor intensity of manufacture, and are difficult to repair when the cylinder group is worn out, since replacing the cylinder liner requires complete disassembly of the engine, since it is bolted to the block head in the assembly from the crankshaft side.

In analogue [4], to ensure good running-in of internal combustion engines on removable liners without scuffing, the minimum allowable deviations of the sleeve holes from cylindricity, taper, and ovality are achieved within acceptable limits by processing the inner diameter by applying a coating by resting, followed by boring and honing, as well as by resting and subsequent grinding of the outer sleeve seating surfaces.

To retain lubricant and improve running-in, a phosphating coating or a layer of porous chromium by galvanic methods can be applied to the inner surface of the sleeve [1].

As a prototype, patent No. 2156370MPK F02F1 / 00 [5] is considered, in which, in order to reduce the coefficient of friction and increase wear resistance, as well as running in, several layers are applied to the working surface of the cylinder liner by spraying an alloy of aluminum and bronze, which can be made more or less solid, provided by the composition of the powder and the mode of application [5].

The application set forth in the prototype is difficult, requires electroplating, several machining operations. The cost of materials and technology is high. The proposed solution is not designed for deviations in the shape of cylinder liners willows minus and plus to the nominal size.

Due to the fact that deviations are possible due to deformations of the cylinder block, the liner itself after installation as a result of tightening the cylinder head bolts and exposing it to large loads through the gas joint, additional stresses are formed in the cylinder liner. The cylinder liner is brought during manufacture or repair to satisfactory parameters in terms of cylindricity, ovality, taper, but its shape is distorted after installation in the cylinder block and tightening of the cylinder head bolts, deviations reach ± 0.02-0.03 mm from the nominal size.

Brief description of drawings and other materials

The condition of the ring-cylinder liner pair significantly affects the durability of the internal combustion engine. For example, there are often cases of unsatisfactory running-in on the working surface of the sleeve (2) and piston rings for engines 8CH12/12 KAMAZ 740 (Figure 1). The reason is the formation of ovality, non-cylindricality, taper of the removable sleeve, which may appear during the installation process, for example, if the order of tightening the bolts by numbers is violated. The ovality of the sleeve may also be due to the asymmetric arrangement of the holes for the bolts of the block head. From the diagram (Figure 2) it can be seen that the holes for the mounting bolts (3) of one cylinder head are located unevenly around the perimeter of a circle with a radius R and at some distance from the gas joint. When tightening four bolts with the same torque, due to the uneven arrangement, the sleeves ovalize. The major axis of the oval is in sectors A and B, and the smaller axis is in sectors C and D.

The objective of this utility model is to create conditions in the internal combustion engine for running in the working surface of a removable cylinder liner with an unloaded gas joint, as well as conditions for the operation of piston rings, under which, despite the formation of a shape deviation, after mounting the cylinder liner and tightening the cylinder head bolts, the surface of the rings and sleeves are mated over the entire area.

To do this, a coating (5) is applied to the working surface of the removable sleeve (4), machined on all surfaces to the final size, which adheres well to the working surface of the cylinder (figure 3), and during operation, due to removal and transfer by piston rings, creates a shape , providing full fit of the entire surface of the rings to the sleeve. To coat the cylinder liner of the internal combustion engine in the claimed utility model, friction brassing was used, which, at lower labor and material costs, provides good conditions for running in and working with compression rings and a piston without rubbing and scoring throughout long-term operation.

The working surface is covered with brass plating on a honing machine CC6101 as follows: a removable sleeve (6) (Fig. 4), finally machined in terms of the inner diameter to size, is installed in the fixture (7) of the honing machine (8) and brassing of the surface of the cylinder liner is performed in a few honing head strokes. The honing head (9) is upgraded for the brass plating process by installing 3 brass rollers (10) instead of honing stones in the presence of a special solution. The rollers (Fig. 5) are wetted with a special solution during working strokes and pressed against the surface by the honing head expansion force, due to which a layer of brass (11) 0.02-0.03 mm thick is applied to the surface of the sleeve (rubbed, smeared). Subsequent machining of the sleeve is not required. With such an applied coating (11), a removable sleeve (12) is installed in the internal combustion engine (Fig. 6), the cylinder head is mounted and the head bolts are tightened. The applied layer of brass adheres well to the main surface of the liner, has good ductility, which leads, during the operation of the piston rings, to its extrusion (scraping) from high-loaded places and transfer to the places of the liner with incomplete fit of the rings, filling them and increasing the size, which leads to an increase in the area contact of the working surface of the rings and the liner, reducing contact pressures and preventing local scoring, burns, seizing of the rings and the liner, which allows operation with a full load of the internal combustion engine, with a uniform pressure of the piston ring surface on the inner surface of the liner without gas breakthrough through incomplete fit through the lubricating oil film .

A special advantage of ICE with removable cylinder liners coated with brass is that the applied layer does not require finishing work, such as boring and honing; does not require large expenditures for implementation and can be carried out in any conditions - when assembling new and repairing internal combustion engines.

Positions on the drawing

Table 1

Position Designation one The working surface of the cylinder liner 2 The section of the working surface of the cylinder liner with unsatisfactory running-in 3 Cylinder head bolt locations 4 Machined to final cylinder liner dimensions 5 Coating of the working surface with a layer of brass 6 Sleeve fitted for brass plating 7 Attachment to the honing machine for installing and fixing a removable sleeve eight Honing machine SS 6101 9 Upgraded honing head 10 brass rollers eleven Brass layer on the working surface of the sleeve 12 ICE under assembly with removable cylinder liners coated with brass

Sources of information

1. KamAZ vehicles: Maintenance and repair of KamAZ vehicles / ed. V.N. Baruna - 2nd ed., revised. and additional - M.: Transport, 1988. - 352 p., (p. 15, fig. 9).

2. Design and strength calculation of piston and combined engines / ed. A.S. Orlina, M.G. Kruglova, M.: Mashinostroenie, 1984. - 384 pp. (p. 313 - 314. fig. 232 b, c).

3. Patent No. 2168045MPK F02F1 / 00, F04B39 / 12 (example).

4. Car repair ZIL-130. Ed. A.G. Lipkind, P.I. Grinberg, A.I. Ilyin. Publishing house "Transport", 1970. 360s. (pp. 40-41, 56-61) (analogue).

5. Patent No. 2156370MPK F02F1/00 (prototype).

Claims (1)

An internal combustion engine, including a cylinder block, cylinder heads docked with it using anchor bolts or studs, as well as removable cylinder liners placed in the block bores, the upper end of which is clamped between the block and the cylinder head, forming a loaded gas joint, characterized in that, in order to compensate for deviations in the macrogeometry of removable sleeves acquired during installation, a running-in layer of brass with a thickness of 0.02-0.03 mm is applied to the inner surface of the removable sleeve processed to the final size.

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