JPH08232754A - Cylinder for internal combustion engine and manufacture thereof - Google Patents

Abstract

PURPOSE: To hold wear resistance against slide of a piston ring while a piston skirt part is prevented from wear damage and to reduce a cost caused by that a need for wear prevention processing for the piston skirt part is eliminated. CONSTITUTION: In the cylinder 1 of an internal combustion engine, surface processing films 8 and 9 are formed on the inner surface of a cylinder liner 4 in such a state to correspond to a piston ring 7 being a sliding mating material, and the surface conditions of portions are differed locally from each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder of an internal combustion engine, and more particularly to a cylinder of an internal combustion engine having an inner surface hardened or surface treated and a method for manufacturing the same.

[0002]

2. Description of the Related Art At present, the inner surface of a cylinder of an internal combustion engine is subjected to uniform hardening treatment and surface treatment so as to cope with severe wear conditions except when cast iron is used. For such hardening treatment, there are some which apply particle dispersion or fiber reinforced alloy. Also, for surface treatment,
The main one is Ni, which is an eutectoid of hard particles such as SiC.
Plating (Nikasil, dispersion plating such as Ni-P-SiC plating) and heated sprayed material Cr ₂ O ₃ -Mo, F
There is a thermal spraying method in which e-Cr-C is sprayed and coated.

A characteristic of these treatments is that hard particles are further present in a hard coating having excellent wear resistance.
The hard particles serve as contact points with the mating material and protect the hard coating of the base material to ensure wear resistance. As the mating material, there is an aluminum alloy piston or a piston ring plated with Cr or the like.

Among them, dispersion plating, which forms an abrasion resistant film, has become the mainstream. In this dispersion plating, Ni, Ni-P, Cr, Cu, etc. are used as a matrix (plating film material), and SiC is used as dispersed particles.
(Silicon carbide), Al ₂ O ₃ (alumina), Si ₃ N ₄
(Silicon nitride), BN (boron nitride), PTFE (polytetrafluoroethylene), MoS ₂ (molybdenum disulfide), diamond and the like are used.

The dispersed particles are functionally classified into two types. 1
One is to secure wear resistance by co-depositing hard particles such as SiC, Al ₂ O ₃ and Si ₃ N ₄ in the film and making it a contact point with the mating material. The other one is for the purpose of co-depositing self-lubricating particles of soft particles such as BN, PTFE and MoS ₂ as dispersed particles to reduce frictional resistance during sliding. The latter is inferior in wear resistance to the former film in which hard particles are co-deposited, but it is less likely to cause seizure or scuffing, and is less likely to damage the mating material. In order to uniformly disperse the dispersed particles in the matrix, it is necessary to select the particle size, suspend the particles,
It is necessary to consider the stirring method of the plating solution and the shaking method of the object to be treated.

[0006]

However, in the above-described conventional internal combustion engine, as shown in FIGS. 11 to 13, the piston thrust of Q in the direction perpendicular to the piston pin 52 is accompanied by the reciprocating rotational movement of the crank 51. Since a force (a force resulting from the swinging behavior) acts, the piston 53 causes the swinging behavior in the DD ′ direction in FIG. Therefore, the contact between the piston 53 and the cylinder liner (cylinder sleeve) 54 is caused not only by the sliding of the piston 53 and the cylinder liner 54 but also by the piston skirt portion 5.
5 and the cylinder liner 54 collide with each other. In FIG. 11, F ₁ is the explosive load, F ₂ is the inertial force due to the reciprocating mass, P is the compressive force of the connecting rod 56, arrow a indicates the reciprocating motion direction, and arrow b indicates the rotating direction.

By the way, the piston ring 57 is plated with Cr, and the cylinder liner 54 is protected by the above-mentioned surface treatment, but the piston skirt portion 55 is exposed with a relatively soft aluminum alloy. As a result, due to the hard particles existing in the surface-treated film of the cylinder liner 54, the piston skirt portion 55 will be worn and damaged. In order to prevent the wear of the piston skirt portion 55, it is necessary to reduce or eliminate the amount of hard particles existing in the surface treatment film of the cylinder liner 54, but this reduces the wear resistance of the cylinder liner 54. Resulting in. Therefore, it is difficult to achieve both the wear resistance of the cylinder liner 54 with respect to the piston ring 57 and the prevention of wear damage to the piston skirt portion 55.

On the other hand, as shown in FIG. 14, in the internal combustion engine in which the inner surface of the cylinder liner 54 is provided with the dispersion plating film 58 in which self-lubricating particles are co-deposited, a racing engine or the like under severe operating conditions is used. Case, piston ring 5
The sliding of No. 7 may cause abrasion of the plating film 58. This wear is mainly due to the decrease in the hardness of the plating film due to the eutectoid of the soft self-lubricating particles on the plating film 58. When the self-lubricating particles are removed from the plating film 58, the film hardness increases, so the piston ring 5
Although it is possible to prevent the plating film 58 from being worn due to sliding with 7, the wear of the piston skirt 55 is likely to occur. Therefore, similarly to the above, it is difficult for the plating film 58, which eutectizes the self-lubricating particles, to have both wear resistance to the piston ring 57 and prevention of wear damage to the piston skirt portion 55.

The present invention has been made in view of the above circumstances, and an object thereof is to prevent abrasion damage of a piston skirt portion while maintaining wear resistance due to sliding of a piston ring, and to provide a piston skirt. It is an object of the present invention to provide a cylinder of an internal combustion engine and a method for manufacturing the same, which can reduce costs by eliminating the process of preventing wear of parts.

[0010]

In order to solve the above-mentioned problems of the prior art, in the present invention, the surface texture of each portion of the inner surface is made to correspond to the sliding mating material by surface treatment or hardening treatment. They are different.

According to another aspect of the present invention, in a cylinder of an internal combustion engine having an inner surface subjected to dispersion plating containing hard particles, the eutectoid amount of the hard particles is set to a value other than that on the sliding surface of the piston ring. It is configured by reducing the sliding surface of the part.

Further, according to another aspect of the present invention, in a cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing hard particles, the eutectoid amount of the hard particles is measured from the piston top dead center to the piston pin position. It is configured by reducing the sliding surface of other parts than the sliding surface.

According to another aspect of the present invention, in a cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing hard particles, the eutectoid amount of the hard particles is adjusted so that the piston pin is moved from the top dead center to the piston pin. At a position between the sliding surface up to the position and the sliding surface where the piston ring does not slide, a sliding surface in an intermediate region where the film hardness is between the sliding surfaces is provided.

In another aspect of the present invention, the plating apparatus is equipped with an aluminum alloy sleeve serving as a cylinder liner, and the plating apparatus and the aluminum alloy sleeve are provided in a plating solution tank, and the plating apparatus is equipped with an injection treatment. A plating solution containing hard particles is sprayed from the tool onto the inner surface of the application site of the aluminum alloy sleeve to perform dispersion plating, thereby producing a cylinder having a sliding surface having different eutectoid amounts of hard particles.

Further, according to another aspect of the present invention, in a cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing self-lubricating particles, a high hardness region is defined with a position immediately below the piston ring at the piston bottom dead center as a boundary. In the high hardness region, the amount of self-lubricating particles is reduced to form a high hardness region.

In another aspect of the present invention, in a cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing self-lubricating particles, the self-lubricating property is defined with a position immediately below the piston ring at the piston top dead center as a boundary. The sliding surface of the inner surface is divided into a high hardness region and a low hardness region by changing the amount of eutectoid particles.

According to another aspect of the present invention, in a cylinder of an internal combustion engine having an inner surface subjected to dispersion plating containing self-lubricating particles, a position immediately below the piston ring at the piston top dead center and a position at the piston bottom dead center. By changing the eutectoid amount of the self-lubricating particles at the position immediately below the piston ring as a boundary, the inner sliding surface is divided into a high hardness region, a medium hardness region and a low hardness region.

[0018]

In the cylinder of the internal combustion engine according to the present invention, by adjusting the eutectoid amount of the hard particles and the self-lubricating particles contained in the dispersion plating, the high hardness corresponding to the mating material with which the piston ring slides. Areas of the inner surface, such as the low hardness area and the low hardness area, have different surface properties, so the piston skirt is not worn and the wear resistance to the piston ring is maintained while preventing the piston skirt from being worn and damaged. The sliding surface can be obtained.

Further, in another method of manufacturing a cylinder for an internal combustion engine according to the present invention, an aluminum alloy sleeve serving as a cylinder liner is attached to the plating apparatus, and the plating apparatus and the aluminum alloy sleeve are arranged in a plating solution tank. Then, a plating solution containing hard particles is sprayed from an injection jig of the plating apparatus onto the inner surface of the application site of the aluminum alloy sleeve to perform dispersion plating, whereby a cylinder having a sliding surface having a different eutectoid amount of hard particles. Since it is manufactured, it becomes possible to reliably produce a film that maintains wear resistance with the piston ring, depending on the portion where the piston ring slides and the portion where the piston ring does not slide.

Further, in the cylinder of the internal combustion engine according to another aspect of the present invention, the eutectoid amount of hard particles or self-lubricating particles contained in the dispersion plating is demarcated at a position immediately below the piston ring at the piston top-bottom dead center as a boundary. The hardness of the sliding surface is divided into a high hardness region, a medium hardness region and a low hardness region by changing the film hardness by adjusting the Prevents stepped wear of the cylinder liner at the boundary between the hardness range and the low hardness range.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the illustrated embodiments.

1 and 2 show an embodiment of a cylinder of an internal combustion engine according to the present invention. In the figure, 1 is a cylinder provided in a cylinder block 2, 3 is a piston that slides in the cylinder 1 and reciprocates between a top dead center and a bottom dead center, and the cylinder 1 is a cylinder liner (cylinder sleeve) 4 Is formed by using. The piston 3 transmits the explosion pressure in the cylinder 1 to the crankshaft 6 via the connecting rod 5, rotates the crankshaft 6, and sucks and compresses the air-fuel mixture and discharges the combustion gas. Piston ring on top (oil ring for 4 cycle engine, second ring for 2 cycle engine) 7
Is fitted, and the piston skirt portion 3a is at the lower part.
Has become.

On the sliding surface of the cylinder liner 4, in order to reduce damage to the internal combustion engine, surface treatment films 8 and 9 are formed on the upper and lower sides by performing dispersion plating containing hard particles. The sliding surface of the cylinder liner 4 wears and scuffs (scratches) due to the piston ring 7 in the early stage of the explosion stroke (near the top dead center position of the piston 3).
It receives a great deal of force, but not so much in other strokes. Therefore, on the sliding surface of the cylinder liner 4, surface-treated coatings 8 and 9 having different properties are formed in two regions as shown in FIG. In addition, in FIG. 1, the solid line indicates the position of the piston 3 at the top dead center,
The chain line shows the position of the piston 3 at the bottom dead center.

That is, with respect to the sliding surface of the cylinder liner 4, with the contact point of the piston ring 7 when the piston 3 is at the bottom dead center as a boundary, the top dead center side is the A area and the opposite side is the B area. Therefore, the piston ring 7 slides in the area A, and wear of the piston skirt portion 3a due to the swinging behavior of the piston 3 mainly occurs in the area B. Therefore, since it is not necessary to consider wear with the piston ring 7 in the B region, a surface treatment film 9 that is softer or less damaged than the surface treatment film 8 in the A region is applied to the sliding surface of the cylinder liner 4. By applying it, it is configured to reduce wear damage of the piston skirt portion 3a.

Next, the case where Ni-P-SiC plating is applied to the sliding surface of the cylinder liner 4 of this embodiment to form the surface-treated coatings 8 and 9 will be specifically described. Ni-P-SiC plating is dispersion plating (composite plating) in which SiC particles, which are hard particles of about Hmv 2500, are co-deposited in a Ni-P plating film having a Vickers hardness of about Hmv 650, and the piston 3 slides. In this case, the SiC particles serve as a contact point with the mating material and play a role of protecting the base material (Ni-P plating). Therefore, while the plating film itself has excellent wear resistance, it also has a problem that the mating material is easily worn (high wear damage resistance).

The method of manufacturing the cylinder liner 4 is as follows. First, as shown in FIG. 2, an aluminum alloy sleeve 10 which is manufactured separately from the cylinder block 2 and serves as a cylinder liner 4 is prepared, and the aluminum alloy sleeve 10 is attached to the plating apparatus 12 together with the anode rod 11. To do. Next, the aluminum alloy sleeve 10, the plating device 12 and the like are put into the plating solution 14 in the plating solution tank 13 to apply a voltage to perform plating.

The plating solution 14 contains Ni ²⁺ ions, hypophosphorous acid, and SiC particles, and Ni, on the surface of the aluminum alloy sleeve 10 of the cathode by the application of voltage.
P and SiC are deposited and co-deposited to form a Ni-P-SiC plating film. Since the SiC in the plating film is hard ceramic particles, it has good wear resistance to the piston ring 7, but has a great effect on wear damage to the piston skirt portion 3a.

Therefore, the plating apparatus 12 is provided with an injection jig 15 made of vinyl chloride, and SiC of a portion (area B) where sliding with the piston ring 7 is not performed using the injection jig 15. The amount of eutectoid is reduced. The injection jig 15 is formed in a cylindrical shape having a large number of injection holes 16 formed on the outer peripheral surface thereof, and the plating solution 14 is evenly sprayed from the injection holes 16 to the inner surface of the aluminum alloy sleeve 10 in the region B. It has become. Also, the injection jig 1
5, one end of a liquid feed pipe 17 is fixed, and the other end of the liquid feed pipe 17 is connected to a liquid feed pump 19 via a connector 18.
Is connected to the plating solution 14
Is collected and sent to the injection jig 15.

In this embodiment, the inner diameter of the aluminum alloy sleeve 10 is 85 mm, the diameter of the injection hole 16 is 5 mm,
The diameter of the liquid feeding pipe 17 is set to 30 mm, and the liquid feeding amount of the liquid feeding pump 19 is set to 70 l / min. In FIG. 2, arrows indicate the flow of the plating solution 14.

By the way, like Ni-P-SiC plating, dispersion plating (composite plating) in which particles are dispersed in a film
It is known that the amount of particle dispersion (eutectoid amount) can be increased or decreased depending on the flow rate of the plating solution contacting the surface to be plated. In the area B in FIG. 2, the injection hole 1 of the injection jig 15
By injecting the plating solution 14 from 6, the surface to be plated (aluminum alloy sleeve 10) is exposed to the plating solution 14 having a higher flow rate than the area A, and as a result, SiC in the plating film 9 in the area B is removed. It is possible to reduce the amount of eutectoid.

Therefore, the surface treatment films 8 and 9 in which the amount of eutectoid SiC as hard particles is smaller in the B region than in the A region
Thus, the aluminum alloy sleeve 10 having the inner surface formed with is formed. Thereafter, the aluminum alloy sleeve 10 is removed from the plating device 12, set as a cylinder liner 4 in a mold, and forged by injecting Al molten metal. Then, the cylinder block material is formed, so that the cylinder 1 as shown in FIG. 1 can be obtained by subjecting the cylinder block material to predetermined machining.

According to the cylinder 1 of the present embodiment, even if the piston 3 slides in the cylinder liner 4, the piston skirt portion 3a has a surface treatment with a smaller amount of eutectoid SiC than the surface treatment film 8 in the A region. Since it slides in the B region where the coating 9 is applied, the piston skirt portion 3 which has been a problem in the past
The wear damage of a can be reduced. Further, in the manufacturing method of this embodiment, the injection of the plating solution 14 promotes the flow of the plating solution 14 in the aluminum alloy sleeve 10 and the supply of Ni ²⁺ ions to the surface of the plating film is performed. It is possible to suppress the generation of a high current portion that causes defective "kogation". Moreover, since the total amount of SiC eutectoid in the entire plated coatings 8 and 9 is reduced, it is possible to reduce the cost of SiC powder, shorten the processing time at the time of post-processing (honing, inner surface grinding), and extend the life of tools such as grindstones. It becomes possible and the cost can be reduced.

In the present embodiment, the Ni-P-SiC plating was described, but the present invention is not limited to this embodiment, and can be generally applied to the plating treatment in which hard particles are codeposited. Also, applicable items can be applied to engine cylinder liners of all shapes and materials of internal combustion engines (not restricted to structures such as 2-stroke and 4-stroke, cylinder block integrated or separate sleeve etc.) .

Further, depending on the sliding condition, it is possible to suppress wear damage of the piston skirt portion 3a by changing the areas A and B shown in FIG. Next, two modified examples of the area A and the area B are shown in FIGS. In these modified examples, the area where the amount of SiC eutectoid is relatively large is
The area is defined as the area, and the area where the amount of SiC eutectoid is reduced is defined as the area B. The same members as those of the embodiment of the invention described above are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 3 shows a first modification of the cylinder of the internal combustion engine according to the present invention. In this modified example 1, in the cylinder liner 4, the region between the top dead center of the piston 3 and the piston pin 20 where the wear condition with the piston 3 is the most severe is the A region, and the other region is the B region. A surface treatment film 8 is applied to the area A of the cylinder liner 4, and a surface treatment film 9 having a reduced amount of eutectoid SiC is applied to the area B. As a result, the wear damage of the piston skirt portion 3a could be further suppressed as compared with the above-described embodiment of the invention. The cylinder 1 according to the first modification is manufactured according to the method for carrying out the invention shown in FIG.

4 and 5 show a second modification of the cylinder of the internal combustion engine according to the present invention. In this modified example 2,
Between the area A and the area B in the cylinder liner 4,
The structure has a region C as an intermediate region. That is, the area A is the same area as in the first modification of FIG.
The area is the same as that of the embodiment of FIG. 1, the area C is located between areas A and B, and the surface treatment coatings 8, 9 and 21 are applied to areas A, B and C, respectively. . In the cylinder liner 4 of the second modification, the plating films 8, 9,
The amount of eutectoid SiC that is co-deposited in No. 21 is A region> C region> B
By decreasing the areas in order, the coating hardness also decreases in the order of A area> C area> B area. Therefore, according to the structure of Modification Example 2, it is possible to avoid a rapid change in the coating hardness at the boundary between the A region and the B region of the cylinder liner 4, and prevent stepped wear of the cylinder liner 4 at the boundary. .

In the method of manufacturing the cylinder 1 according to the second modification, the shapes of the injection jig 15 and the injection hole 16 in FIG. 2 are changed to have the structure shown in FIG. This structure is basically the same as that shown in FIG.
It is necessary to increase the amount of SiC eutectoid of the plating film 21 in the region than that of the plating film 9 in the B region. Therefore, the arrangement density of the injection holes 26 in the injection jig 25 is changed.

Specifically, the disposition density of the injection holes 26 for injecting the plating solution onto the aluminum alloy sleeve 10 corresponding to the C region of the plating film 21 is made smaller than that in the B region. That is, the number of injection holes 26 per unit area in the C region is smaller than that in the B region. As a result, the area C is exposed to the plating solution having a relatively low flow rate with respect to the area B. As a result, the amount of eutectoid SiC in the plating film 21 in the C region increases with respect to the plating film 9 in the B region, and the film hardness in the C region is the same as that in the A region and
This is between the regions, and it becomes possible to prevent stepped wear of the cylinder liner 4.

The jetting jig 25 shown in FIG. 5 is an example of the jig used for carrying out the present invention, and the application of the present invention is not limited to this jetting jig 25. Also, A
Also in the areas C to C, the areas can be changed by changing and modifying the jig based on factors such as the shape, type, and combustion conditions of the engine, and the areas A to C are limited to those shown in the present invention. Not done. That is, according to each of the embodiments of the present invention, the treated film 9 having a small amount of SiC eutectoid can be formed at an arbitrary position.

FIGS. 6 and 7 show another embodiment of the cylinder of an internal combustion engine according to the present invention. The same members as those of the above-mentioned invention are designated by the same reference numerals and the description thereof will be omitted. In the embodiment of the present invention, when performing the dispersion plating in which the self-lubricating particles are co-deposited on the inner surface of the cylinder 1, the eutectoid amount of the self-lubricating particles on the sliding surface of the piston ring 7 is set to be smaller than that of other portions. By reducing the
The structure is designed to achieve both the wear damage prevention of a and the wear resistance of the inner surface of the cylinder 1 due to the sliding of the piston ring 7.

That is, in the case of a plating film in which self-lubricating particles are co-deposited, the hardness of the plating film and the coefficient of friction decrease due to the softness of the self-lubricating particles. No wear damage of the portion 3a occurs. However, wear of the plating film occurs when the piston ring 7 slides due to the low hardness of the plating film. On the other hand, in the case of a plating film with a reduced amount of self-lubricating particles, the wear of the plating film does not occur when the piston ring 7 slides due to an increase in film hardness, but on the other hand, wear damage to the piston skirt portion 3a occurs. Will happen.
Therefore, in the embodiment of the present invention, by providing the inner surface of the cylinder 1 with a high hardness region in which the amount of eutectoid particles of self-lubricating particles is reduced and a low hardness region in which it is not, or an intermediate hardness region between them, We are trying to address the above issues.

Thus, the cylinder liner 4 of this embodiment
The sliding surface of is divided into hardness regions with the position D directly below the piston ring 7 when the piston 3 is at the bottom dead center as a boundary, and the top dead center side where the piston ring 7 slides is in the high hardness region. The area A is the area A, and the opposite side on which the piston ring 7 does not slide is the area B of the low hardness area. Therefore, in the area A, the self-lubricating particles that are co-deposited in the plating film are reduced to produce the high hardness plating film 28, and in the area B, the self-lubricating particles that are co-deposited in the plating film are reduced without decreasing. The hardness plating film 29 is produced.

Next, the sliding surface of the cylinder liner 4 of this embodiment is plated with Ni-P-BN to form a plating film 28,
The case of forming 29 will be specifically described. Ni-P-B
N plating is Ni with Vickers hardness of about Hmv650.
-P plating film is dispersion plating (composite plating) in which BN particles that are soft self-lubricating particles are co-deposited.
The eutectoid of the particles lowers the hardness and friction coefficient of the plating film. Further, the wear resistance against sliding with the piston ring 7 also decreases. In the cylinder liner 4 of this embodiment, the plating film 28 in the A region of the high hardness region
The amount of BN particle co-deposition is reduced to increase the film hardness, and the plating film 29 in the B region of the low hardness region has a normal BN particle co-deposition amount (3 to 8 area%).

The method of manufacturing the cylinder liner 4 having the plating films 28, 29 described above is as follows. First, as shown in FIG. 7, an aluminum alloy sleeve 10 prepared separately from the cylinder block 2 is prepared, and the aluminum alloy sleeve 10 and the anode rod 11 are attached to the plating apparatus 22. In the plating apparatus 22 of the present embodiment, the injection jig 35 is suspended on the anode rod 11 by using the suspension material 23 in order to reduce the amount of BN particle eutectoid in the A region of the high hardness region. The injection jig 35 is formed in a cylindrical shape having a large number of injection holes 36 formed on the outer peripheral surface thereof, and the plating solution 24 is uniformly applied to the inner surface of the aluminum alloy sleeve 10 in the area A from the injection holes 36. It is supposed to be sprayed.

Further, one end of the liquid feed pipe 17 is fixed to the injection jig 35, and the other end of the liquid feed pipe 17 is connected to a liquid feed pump 19 via a connector 18. The liquid feed pump 19 collects the upper layer 24a of the plating solution having a relatively low BN suspension amount through the sampling port 37, and the injection jig 35.
It is configured to deliver liquid to. The implementation conditions of this embodiment are the same as those of the embodiment of FIG. Moreover, Ni-P
-BN plating is also Ni-P-Si in the embodiment of FIG.
Similar to C plating, the amount of particle dispersion (eutectoid amount) can be increased or decreased depending on the flow rate of the plating solution.

Therefore, in the high hardness region A in FIG. 7, the plating solution 24 from the injection hole 36 of the injection jig 35 is discharged.
Is exposed to the plating solution 24a having a higher flow velocity and a smaller amount of BN suspension than in the area B, and as a result, the BN in the plating film 28 in the area A is exposed.
It is possible to reduce the amount of eutectoid particles. As a result, the hardness of the area A can be increased. The other manufacturing procedure is the same as that of the embodiment of the invention shown in FIGS.

A cylinder 1 manufactured by using the cylinder liner 4 of the present embodiment is provided with BN as self-lubricating particles.
(Boron Nitride), PTFE (Polytetrafluoroethylene), MoS ₂ (Molybdenum disulfide)
It was co-deposited on the i-P plating film, and the film formation state was observed, the film hardness, and the engine sliding test. The results are shown in Table 1 below.

[0048]

[Table 1]

From the above results, it can be seen that in the dispersion plating using the self-lubricating particles, the above effect is exhibited by Ni.
It turned out that -P-BN plating is the most desirable. The above-mentioned BN includes a hexagonal crystal and a tetragonal crystal, but it is limited to a hexagonal crystal exhibiting self-lubricating property.

Next, another embodiment of the present invention will be described. This example is similar to the above example in that B is a low hardness region.
While increasing the BN eutectoid amount in the region, the high hardness of the A region, which is a high hardness region, is maintained. in this case,
Plating solution 24 from plating solution lower layer 24b with a large amount of BN suspension
Is sampled and is sprayed on the A region of the high hardness region as in the above-mentioned embodiment. At this time, since the plating solution 24 to be sprayed has a larger amount of BN suspension than that in the above-mentioned embodiment, it is necessary to increase the spraying flow rate.

The plating solution 24 that collides with the cylinder liner 4 corresponding to the area A loses the flow velocity at the time of collision. Then, the suspended BN particles settle, and in the process, eutectoid in the B region of the low hardness region. This makes it possible to maintain high hardness in the A region and increase the amount of BN eutectoid in the B region. Here, the implementation conditions changed from the embodiment shown in FIGS. 2 and 7 are as follows. That is, the diameter of the injection hole 36 is φ4 mm and the diameter of the liquid supply pipe 17 is φ45.
mm, the liquid feed rate of the liquid feed pump 19 is 110 l / min, and the position of the sampling port 37 is set in the plating liquid lower layer 24b.

The present invention is not limited to the above-mentioned embodiments, but various modifications and changes can be made based on the technical idea of the present invention.
One modification example is shown in FIGS. The same members as those in the above embodiment are designated by the same reference numerals and the description thereof will be omitted.

FIG. 8 shows a modification 1 of the cylinder of the internal combustion engine according to another embodiment of the present invention. In the modified example 1, in the cylinder liner 4, the hardness region is divided with the position E immediately below the piston ring 7 when the piston 3 is at the top dead center as a boundary, and the wear condition with the piston 3 is the most severe. The dead point side is the A region of the high hardness region, and the opposite side is the B region of the low hardness region. As a result, the wear damage of the piston skirt portion 3a could be further suppressed as compared with the above embodiment. The cylinder of Modification Example 1 is manufactured according to the implementation method shown in FIG. 7.

9 and 10 show a modification 1 of the cylinder of the internal combustion engine according to another embodiment of the present invention. This modification 2
Has a structure in which a C region is provided as a medium hardness region between the A region and the B region of the cylinder liner 4. That is, the area A is the same area as the modification 1 of FIG. 8, the area B is the same area as the embodiment of FIG. 6, the area C is located between both areas A and B, and , C
Plating films 28, 29, 30 are applied to the regions, respectively. In the cylinder liner 4 of Modification Example 2, the eutectoid amount of BN particles co-deposited on the plating films 28, 29, 30 is increased in the order of A region <C region <B region.
The film hardness decreases in the order of A region> C region> B region.

The manufacturing method of Modification 2 can be dealt with by changing the shape of the injection hole 36 of the injection jig 35 in FIG.
That is, in the injection jig 45 shown in FIG. 10, the plating films 28, 3 in the A region of the high hardness region and the C region of the medium hardness region are formed.
In order to change the eutectoid amount of BN particles in 0, the injection holes 46a (diameter: φ5 mm, 1.5 /
cm ² ) and the injection hole 46b in the C region (diameter: φ7 mm, 0.
The hole diameter and the density of 5 holes / cm ² ) are changed. As a result, the flow velocity of the plating solution 24 impinging on the inner surface of the aluminum alloy sleeve 10 is gentler in the C region than in the A region, and as a result, the hardness of the plating film is changed.

Therefore, according to the structure of Modification 2, the A region of the high hardness region, the C region of the medium hardness region and the B region of the low hardness region are used.
The film hardness and the BN eutectoid amount in the area are Hmv
650 (0.4 area%), Hmv600 (2.5 area%) and Hmv540 (6.5 area%),
It is possible to avoid a rapid change in the film hardness at the boundary between the A region and the B region in the cylinder liner 4, and prevent stepped wear of the cylinder liner 4 at the boundary.

[0057]

As described above, in the cylinder of the internal combustion engine according to the present invention, the surface texture of each portion of the inner surface is made different according to the mating material to be slid by the surface treatment or the hardening treatment. The abrasion resistance of the piston ring against sliding can be maintained by the treatment film while preventing the wear damage of the part, and it is not necessary to apply the wear prevention process (such as alumite) to the piston skirt part, which contributes to the cost reduction. it can.

Further, the cylinder of the internal combustion engine according to the present invention is such that the inner surface thereof is subjected to dispersion plating containing hard particles, and the eutectoid amount of the hard particles is more than that on the sliding surface of the piston ring. The sliding surface of other parts is reduced, or the sliding surface of other parts is reduced compared to the sliding surface from the piston top dead center to the piston pin position. The wear damage of the skirt can be prevented more effectively.

Further, the cylinder of the internal combustion engine according to the present invention is such that the inner surface is subjected to dispersion plating containing hard particles, and by adjusting the eutectoid amount of the hard particles, the piston top dead center can be increased. Provide a sliding surface in the intermediate range where the film hardness is between the sliding surfaces, between the sliding surface up to the piston pin position and the sliding surface where the piston ring does not slide. Because of the presence of the intermediate range of medium hardness, the hardness of the boundary can be gently changed from the high hardness region to the low hardness region, and the stepped wear of the cylinder liner and the wear damage of the piston skirt part can be further reduced. It can be prevented more effectively.

In the method for manufacturing a cylinder for an internal combustion engine according to the present invention, the plating apparatus is equipped with an aluminum alloy sleeve which serves as a cylinder liner, and the plating apparatus and the aluminum alloy sleeve are arranged in a plating solution tank. A plating solution containing hard particles is sprayed from an injection jig of the plating device onto the inner surface of the application site of the aluminum alloy sleeve to perform dispersion plating, thereby producing a cylinder having a sliding surface with different eutectoid amounts of hard particles. Therefore, it is possible to reliably produce a coating that maintains wear resistance with the piston ring depending on the part where the piston ring slides and the part that does not slide, and the combustion conditions of each engine and the piston of the mating material Depending on the type of ring material and piston material, the hardness of the plating film on each part of the inner surface of the cylinder liner can be easily adjusted by adjusting the jig. It becomes possible to change, the cost required for the jig adjustment inexpensively requires.

Further, another cylinder of the internal combustion engine according to the present invention is such that the inner surface thereof is subjected to dispersion plating containing self-lubricating particles, and the position immediately below the piston ring at the piston bottom dead center is taken as a boundary. It is divided into a high hardness region and a low hardness region, and in the high hardness region, the eutectoid amount of self-lubricating particles is reduced to form a high hardness region, or a position immediately below the piston ring at the piston top dead center is used as a boundary. By changing the eutectoid amount of self-lubricating particles, the sliding surface of the inner surface is divided into a high hardness region and a low hardness region. However, the plating film can maintain the abrasion resistance against sliding of the piston ring, and it is not necessary to apply abrasion prevention treatment (such as alumite) to the piston skirt, which contributes to cost reduction. That.

Further, the cylinder of the internal combustion engine according to the present invention is such that the inner surface thereof is subjected to dispersion plating containing self-lubricating particles, and the position immediately below the piston ring at the piston top dead center and the piston bottom dead center. By changing the eutectoid amount of self-lubricating particles at the position immediately below the piston ring as a boundary, the inner sliding surface is divided into a high hardness region, a medium hardness region and a low hardness region. Similarly to the above-mentioned invention, the presence of the medium hardness region allows the hardness of the boundary portion to be gradually changed from the high hardness region to the low hardness region, so that the stepped wear of the cylinder liner and the wear damage of the piston skirt part can be prevented. It can be prevented more effectively.

[Brief description of drawings]

FIG. 1 is a sectional view conceptually showing the positional relationship between a cylinder liner and a piston used in a cylinder of an internal combustion engine according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a manufacturing process of the cylinder liner.

FIG. 3 is a sectional view conceptually showing the positional relationship between the cylinder liner and the piston according to the first modification of the present invention.

FIG. 4 is a sectional view conceptually showing the positional relationship between a cylinder liner and a piston according to a second modification of the present invention.

FIG. 5 is a conceptual diagram showing a manufacturing process of a cylinder liner according to the second modification.

FIG. 6 is a sectional view conceptually showing a cylinder liner used in a cylinder of an internal combustion engine according to another embodiment of the present invention.

7 is a conceptual diagram showing a manufacturing process of the cylinder liner of FIG.

FIG. 8 is a sectional view conceptually showing another cylinder liner according to Modification 1 of the present invention.

FIG. 9 is a sectional view conceptually showing another cylinder liner according to Modification 2 of the present invention.

FIG. 10 is a conceptual diagram showing a manufacturing process of the cylinder liner in FIG.

FIG. 11 is a conceptual diagram illustrating a force acting on a cylinder of a conventional internal combustion engine.

FIG. 12 is a plan view conceptually showing a conventional piston and cylinder liner.

FIG. 13 is a sectional view conceptually showing a conventional piston and cylinder liner.

FIG. 14 is a sectional view conceptually showing the positional relationship between a cylinder liner used in a cylinder of an internal combustion engine and a piston in another conventional example.

[Explanation of symbols]

 1 Cylinder 2 Cylinder Block 3 Piston 3a Piston Skirt 4 Cylinder Liner 7 Piston Ring 8,9,21 Surface Treatment Coating 10 Aluminum Alloy Sleeve 11 Anode Rod 12,22 Plating Equipment 13 Plating Tank 14,24 Plating Solution 15,25,35 , 45 Injection jig 16, 26, 36, 46a, 46b Injection hole 17 Liquid delivery pipe 18 Connector 19 Liquid delivery pump 20 Piston pin 23 Suspension material 28, 29, 30 Plating film 37 Collection port

Claims (9)

[Claims] 1. A cylinder of an internal combustion engine, characterized in that the surface property of each part of the inner surface is made different by a surface treatment or a hardening treatment so as to correspond to a sliding mating member. 2. In a cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing hard particles, the eutectoid amount of the hard particles is determined in the sliding surface of other parts than in the sliding surface of the piston ring. A cylinder of an internal combustion engine, which is configured by reducing the number of cylinders. 3. In a cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing hard particles, the eutectoid amount of the hard particles is other than that of the sliding surface from the piston top dead center to the piston pin position. A cylinder of an internal combustion engine, characterized in that the sliding surface of the part is reduced. 4. In a cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing hard particles, the sliding surface from the piston top dead center to the piston pin position by adjusting the eutectoid amount of the hard particles. And a sliding surface of a portion where the piston ring does not slide, a sliding surface in an intermediate region having a film hardness between the sliding surfaces is provided. . 5. An aluminum alloy sleeve serving as a cylinder liner is mounted on the plating apparatus, the plating apparatus and the aluminum alloy sleeve are arranged in a plating solution tank, and plating containing hard particles from an injection jig of the plating apparatus. A method for manufacturing a cylinder for an internal combustion engine, characterized in that the liquid is sprayed onto the inner surface of the application site of the aluminum alloy sleeve to perform dispersion plating, thereby manufacturing a cylinder having a sliding surface having different eutectoid amounts of hard particles. 6. The internal combustion engine according to claim 5, wherein the plating solution injection holes of the injection jig are provided with different densities depending on parts so as to change the amount of eutectoid particles of the plating film. Engine cylinder manufacturing method. 7. A cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing self-lubricating particles, is divided into a high hardness region and a low hardness region with a position immediately below the piston ring at the piston bottom dead center as a boundary, A cylinder of an internal combustion engine, characterized in that the amount of self-lubricating particles in the high hardness region is reduced to a high hardness. 8. In a cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing self-lubricating particles, the eutectoid amount of self-lubricating particles is changed at a position immediately below the piston ring at the piston top dead center as a boundary. Accordingly, the cylinder of the internal combustion engine, wherein the inner sliding surface is divided into a high hardness region and a low hardness region. 9. A cylinder of an internal combustion engine, the inner surface of which is subjected to dispersion plating containing self-lubricating particles, has a boundary between a position just below the piston ring at the piston top dead center and a position just below the piston ring at the piston bottom dead center. A cylinder of an internal combustion engine, characterized in that the sliding surface of the inner surface is divided into a high hardness region, a medium hardness region and a low hardness region by changing the eutectoid amount of the self-lubricating particles.