JPS603463A - Cylinder for engine - Google Patents

Abstract

PURPOSE:To heighten a lubricating effect lying between a cylinder inner wall and a piston ring sliding surface as well as to improve sliding characteristics in a cylinder, by installing a lot of oil holding concave parts whose each sectional form is of almost U-shaped type by means of a photetching process, on the cylinder inner wall of an engine. CONSTITUTION:On the inner wall of a cylinder liner 2, there are provided with a lot of oil holding concave parts 5 whose each sectional form is os almost U- shaped type by means of a photoetching process and has a circular opening form independent with one another, engraved at equal pitch intervals over the whole inner wall surface. In this case, the said oil holding concave parts 5 are set down to 10-50% in terms of area ratio, while it is desirable that deepness be below a straight line connecting a point of depth 50mu at the area ratio of 10% to a point of depth 30mu at the area ratio of 50% as well as be above a straight line connecting a point of depth 10mu at the area ratio of 10% to a point of depth 3mu at the area ratio of 50%.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an engine cylinder that can withstand long-term use and is suitable for high-output engines.

(Prior art) Conventionally, as an engine cylinder with good sliding characteristics, for example, a large number of X-shaped (cross-hatched) seedlings are stacked on the inner wall of a cast iron liner by honing and arranged side by side. By forming an appropriate oil film on the cylinder inner wall with engine oil held in the crosshatching groove,
It is well known that screws are designed to provide good lubrication with the sliding surface of the ring. By increasing the amount of oil retained in this gap and crosshatching groove, a stable oil film can be formed under various usage conditions, which further enhances the above-mentioned lubrication effect and improves the cylinder's sliding characteristics. It is possible to improve the properties and maintain the properties for a long period of time. In particular, this means that the average effective pressure can be increased with equipment such as a supercharger, or that the combustion can be improved to a maximum of ^1:
21 Internal pressure is increased 1. :In engines, this prevents scuff ink due to increased surface pressure on the sliding surface of the piston ring, and in engines with a high maximum rotation speed, it prevents scuffing due to increased piston speed, improving the reliability of these high-output engines. It is beneficial for increasing the

Therefore, it is possible to avoid increasing the amount of oil retained by deepening the engraving depth of the crosshatching mentioned above.However, in this case, honing will be performed using a grained grindstone. , to Figure 14/No. 167
As shown in the figure (enlargement magnification 1000 (+3)),
The protrusions c, d, and e formed by force curvature, overlap, and plastic flow in the gap 1-part 1) between ita become large, and the protrusions c, d.

As wear ω of the piston ring surrounding e increases, its sliding resistance increases and the gas seal 1g. There is a problem in that the use of prove-by gas increases due to the deterioration of the gas.

Furthermore, since the cross-hatched cross-hatching formed by this honing process has a roughly V-shaped cross-section as shown in the figure, as the inner wall of the cylinder wears, its area ratio increases, i.e., the total The value obtained by dividing the total opening area of the cross-hunting a by the total area of the inner wall portion of the cylinder in which the leak a is carved rapidly decreases. For this reason, the volume of the tea becomes small and the amount of oil retained decreases rapidly, making it impossible to maintain the initial sliding characteristics for a long period of time.
A problem will occur. In addition, due to multiple area processing,
Cross hatching a... cannot be formed into a uniform shape and its distribution is irregular. There is also a problem in that scuff ink is generated from areas where D is sparse.

In addition, as a method θ for carving the oil retaining portion on the inner wall surface of the sill with good workability, there is a porous surface [1 mmettsu method]. Rinawara, the example is 'If lηi flit 53
J: Sea urchin disclosed in Publication No. 38699, the inner wall surface of the cylinder is chromium plated, and this plating layer is subjected to reverse electric treatment, and a groove-like channel type porous is carved. Alternatively, a pinpoint type porous shape for a thank you note can be engraved by cutting the treated surface. However, this method
If the amount of reverse electrolysis is increased in order to deepen the engraving depth of the lath, the electrolysis will be promoted (as shown in Figure 17 (enlargement magnification: 400) (8), part of the plateau between porous 1 g-t). The surface roughness increases. Therefore, it may be possible to perform a surface lapping treatment on the plated surface after electrolysis to reduce the surface roughness. However, in the case of porous "Tirenel type", the cross-sectional shape is sharp V due to cracks caused by internal stress.
On the other hand, in the case of the pinpoint type, the cross-sectional shape is V-shaped because the frontage is expanded while collapsing the chrome plating layer by grinding, and for this reason, both types of porous As the inner wall of the cylinder wears, the area ratio rapidly decreases and the amount of oil retained becomes insufficient. In addition, the shape of some parts of the J-ri-ara 1 is not constant due to the plating process regulations (hardness, thickness, internal stress), and the grinding strip '1 when converting to the pinpoint 1 is J-ribo. Since the degree of lathization varies, the shape and distribution of the pores vary. 1 = Gap, and the above honing process can also be achieved by forming a porous layer using this porous chromium plating method.
Cross hunting r by two! The same problem occurs when /i is engraved, and no effect can be expected in improving I behavior characteristics.

Roughly, the above honing method and energized porous black l\
Even in the plating method, in order to have long-term oil retention ability and to obtain a sufficient area ratio of four parts, it is necessary to significantly reduce the initial area ratio of one part to one part. You won't get any more. In the first place, some parts, such as piston rings and piston thrust parts, are in sliding contact under high pressure, so it is important to reduce the surface pressure per unit surface in order to obtain wear resistance and scuffing resistance. Therefore, the higher the lubricity, the more desirable it is. Furthermore, from the standpoint of ensuring gas sealing properties, it is good to have no oil retaining recesses and no surface irregularities. For this reason, oil retention is necessary for the I3, but increasing the area ratio of the recesses will not improve the performance.There is a limit to the area ratio of the recesses, especially in a high-speed, high-load engine. It's about Sara.

What is desired from these points is to secure a concave shape that will not reduce the initially set area ratio of the four oil holding parts even if wear progresses, and if this is possible, the strength and durability of the plateau part will be improved. and ρ, which can satisfy the contradictory properties of lubricity and lubricity.

On the other hand, the photo-etching method is known as a processing method for engraving various shapes of parts on metal surfaces and for opening holes.
For example, it is applied to the processing of electric razor blades, shadow masks for can-TVs, and spherical bearings.

<Object of the Invention> The object of the present invention is to provide a cylinder that can withstand long-term use as described above and is also suitable for use in high-mountain J engines.
The purpose is to improve the sliding characteristics of the cylinder by increasing the lubrication effect with the piston ring sliding surface through a simple structure using a photo-etching method.

(Structure of the Invention) In order to achieve the above objects, the solution of the present invention is characterized in that a large number of oil retaining recesses each having a substantially U-shaped cross section are provided on the inner wall of the cylinder of the engine by the foot t-etching method. That is.

Therefore, in the present invention, the surface roughness of the portion between the mail holding recesses is made minute by adjusting the photoetching processing conditions, and the depth of the gap between the mail holding recesses is increased to increase the amount of mail holding. It has a J-shaped cross-sectional shape to reduce the decrease in the frontage area of the four oil holding parts due to wear of the cylinder inner wall, and oil holding recesses are regularly carved on the cylinder inner wall without variation. .

In this case, the four oil holding parts are set to have an area ratio of 10 to 50% as shown in FIG.
A point with a depth of 50 μ at an i rate of 10% and a depth of 30 μ at an area rate of 50 tt (1) A point with a depth of 10 μ and an area rate of 50 that is below the straight line of Il + i and with an area rate of 10%. By connecting a point with a depth of 3μ below % and setting it in a range more than a straight line, a sufficient oil film is formed on the inner wall of the cylinder, and the strength of the four oil retaining parts and the plateau part of the edge is ensured. It is advantageous because it can be made easily and the wear of the sliding surface of the screw 1 ring can be suppressed. 1 <Effects of the Invention> Therefore, according to the present invention, a portion of the plateau on the surface of the cylinder inner wall is formed using a simple structure in which a large number of four oil retaining portions each having a substantially U-shaped cross section are provided on the cylinder inner wall using a photoetching method. While ensuring the area ratio of (1b1) and the size and strength of each plate part, on the other hand, increasing the A oil retaining claw of the oil retaining recess to form a stable oil film on the cylinder inner wall. Since the decrease in mail retention m due to wear can be reduced and the distribution of the oil film can be made uniform, it is possible to improve the cylinder behavior characteristics. Not only does it extend the life of the engine over a long period of time, but it also has the profound effect of improving the reliability of the engine. In particular, the oil retaining recess is
As shown in the figure, the area ratio is 10 to 50%, and
Below the straight line Jme connecting the point J5 at a depth of 50μ at an area ratio of 10% and the point at a depth of 30μ at J34J at an area ratio of 50%, and the area; the point at a depth of 10μ at t7 10% and the area ratio 6 in the range above the straight line connecting 50% and a point with a depth of 3 μ in J5! If determined, the above-mentioned effects can be further enhanced while ensuring the strength of the plateau part of the peripheral edge of the four oil retaining parts and suppressing wear of the piston ring sliding surface.

(Example) Hereinafter, an example as a specific example of the technical means of the present invention will be described based on the drawings.

FIG. 1 shows an embodiment of the present invention. In the figure, reference numeral 1 indicates a cylinder block of an engine, and reference numeral 2 indicates a cylinder line inserted within the cylinder block 1, with the cylinder line 2 forming a cylinder 3 within the cylinder block 1. , 4 is the flow of cold Ml water A
-Tajaketsu 1~.

On the inner wall of the cylinder 3 (inner wall of the cylinder type 2),
J stiffness in photo etching method Figure 2 (enlarged in) rate 10
The oil holding recesses 5 are independent from each other and have a cross-sectional shape of a scribble shape and a circular frontage shape as shown in (0x).
・ are engraved on the entire inner wall at equal pitches in the vertical and horizontal directions.

To explain the method of forming the four oil retaining parts 5 by the enching method, first, as shown in Figure 3, an enlarged original drawing of the four oil retaining parts 5 is prepared, and this is reduced by the darkest part in Photo 1. The transparent parts are arranged vertically and horizontally at predetermined intervals on the sheet.
Create a negative film-like photomask. clearly,
A UV-sensitive film is pasted onto the inner wall of the sill 3 that has been cleaned with an organic solvent using a film pasting roll, and the photomask is placed on top of the film in close contact with it. In this state, by exposing the surface of the mask to photo 1 with ultraviolet rays,
Photocure the film portion corresponding to .

Then, the photomask is removed and the film is developed to dissolve and remove the cured portion (unexposed portion) to form a mask on the inner wall of the cylinder 3. Really, this cylinder 3
The inner wall is etched, the parts not covered by the -2 mask (corresponding to the oil holding recesses 5...) are corroded, the oil holding parts 5... are etched, and then the mask is removed. Complete the work. In the above embodiment, an ultraviolet-sensitive film was used, but a photoresist (photosensitive agent) was applied to the inner wall surface of the cylinder 3, and this was dried and cured to form a photoresist film.
11-Resist I/A film formed with a film may be used.

Further, the oil holding recess 5 has, as shown in FIG.
The area ratio, that is, the total opening area of all oil holding recesses 5... divided by the total area of the inner wall of the cylinder 3 (IC1 is 10 to 5
0%, and the depth is less than or equal to the straight line i connecting the point at depth 50μ that goes down to the surface (6 ratio 10%) and the point depth 30μ that goes down to area ratio 50% (), and the area ratio is 10 The range S is set to be greater than or equal to the straight line connecting the 10μ depth point in %() and the 3μ depth point in area ratio 5096.

Next, the reason why the area ratio a3 to width of the oil retaining recess 5 is limited will be explained. Area ratio 10-50
% because if it is less than 10%, the amount of oil retained in the oil retaining recess 5 is small and a sufficient oil film cannot be formed on the inner wall of the cylinder 3, causing scuffing.On the other hand, if it exceeds 50%, scuffing will occur. [Plastic] - The area of some thin bodies becomes too small. Wear resistance 11. In addition to this, the thickness of the periphery of the oil retaining recess 5 becomes thinner, causing deformation and collapse of the periphery, resulting in fine scratches, and the increased length of the periphery causes piston ring sliding. This is because surface wear increases. The depth is limited to less than a straight line connecting a point with a depth of 50μ at an area ratio of 10% and a point with a depth of 30μ at an area ratio of 50%. This is to cover the wounds caused by the collapse to prevent further damage. In addition, when forming the A-il 1^ holding recess in a groove shape, it is necessary to suppress the oil leakage through the recess to a predetermined value [) or less.
It is advantageous to limit the depth as described above. Furthermore, the depth was limited to a straight line connecting the 10μ depth point with the area ratio of 10% and the 3μ depth point with the area ratio of 50%. This is to prevent scuffing by ensuring a sufficient amount of oil is retained.

Incidentally, the above-mentioned oil retaining parts;
I! The i ratio is calculated by dividing the total opening area of all the oil holding recesses 5 by the total area of the inner wall portion of the cylinder 3 in which the recesses 5 are carved.

Therefore, in the above embodiment, since a large number of oil holding recesses 5 were carved in the inner wall of the cylinder 3 by the first etching method, the recesses 5 were formed by adjusting the etching strip '1 as appropriate. The deeper the depth, the more oil it can hold. As a result, a stable oil 161 can always be formed on the inner wall of the cylinder 3, and the lubrication effect of the sliding motion of the piston ring can be smoothly enhanced, making it possible to improve the sliding characteristics of the cylinder 3. Regarding this J:
In general engines, it prolongs the life of the sill, and in high-output engines, it prevents scuffing caused by -12R of surface pressure on the sliding surface of the bisto sill, as well as cuffing and increased piston speed. Its reliability can be increased.

In addition, since the oil retaining portion 5 (uncross-sectional shape) is formed in a substantially U-shape, the decrease in area ratio due to wear of the inner wall of the cylinder 3 is significantly less than that of the conventional V-shaped full or porous oil retaining portion 5. This is due to the fact that the volume of the recess 5 holds oil m)
Since the initial sliding characteristics can be maintained for a long period of time, the life of the cylinder can be extended by a long time.

Furthermore, the oil holding recesses 5 are carved in the inner cavity of the cylinder 3 following the transparent parts that are arranged with high precision at predetermined bit intervals on the same original drawing on the first mask. The frontage area and depth of each recess 5 are made uniform, and the recesses 5 can be regularly avoided by the molecules li of the oil film formed on the inner wall of the cylinder 3.
This makes it possible to prevent snoring from occurring locally.

In addition, during etching, the part covered by the mask (the part formed between the oil holding recess 5...) is not cut and corroded and is left as a mirror surface, reducing wear on the sliding surface of the first piston ring. It can reduce the sliding resistance, improve the gas sealing property, and reduce the amount of blow-by gas.

In addition, since the photoedzip method was used, machining heat is not generated like in conventional honing, so cylinder 3
The inner wall will not be deformed or altered or become work hardened.
Quality control is important. What's more, you can freely create masks with various patterns, so it's easy to use!
, there is an advantage that the shape and distribution of the holding portions 5 can be arbitrarily selected.

In the above embodiment, an engine of the type in which the cylinder liner 2 is fitted into the cylinder block 1 has been described, but the present invention can also be applied to an engine of the type in which the cylinder is directly formed in the cylinder block. 7.Next, regarding specific examples, d (clearly covered.r2 Table 1 shows examples of the present invention in which four oil retaining parts are engraved on the base material as in Example -1). ) and precision finish lapping, those with ('shudging recesses engraved by honing, and conventional examples) with J, Ribinboin 1-type porous engraved on the bolus chrome metal skin, A wear test was performed.

Table 1 The wear test was carried out by attaching a base material 8 formed into a disk shape (diameter φ180n+m, thickness 20mm) to the rotating drive shaft 6, as shown in FIG. In addition to supplying lubricant from pellet h 10 through felt 9 onto 8,
A rectangular parallelepiped (contact surface and
...The bottle 12 (3n+m x 15mm, thickness 8.5cm) is attached to the other end of the arm 11 through the slider 13 (the gravity of the weight 14 pushed onto the plate 408). This is Shino.

Table 2: Under the above experimental conditions, the circumferential speed of the base material 8 is 2 O
n+ /sec, the weight of the weight 14 is 30 kq, and the lubricant is a mixture of 9 parts kerosene to 1 part engine oil with a viscosity of 10W-40, and the temperature rises to about 100'C during engine operation. Adjusted to have the same viscosity as engine mail. In addition, the oil retaining recess of the example of the present invention has a halftone dot shape with a circular opening as in the embodiment described above, and has an angle θ (145°) shown in FIG. A crosshatch type with grooves intersecting in an X-shape is also available.
A negative type resist with a CJ width of 8μ is used for one-sided optical film, and exposure is carried out using a 1kW clamp with a light emitting part length of 20cm.
This was carried out for 5 minutes using a high-pressure mercury lamp. and,
Development was carried out by immersion in 1.1.1 trichloroethane for 5 minutes, and as a J-tsuching solution, 10-15 vol. A solution of C1.203 (250 teeth/9) and H2SOa (2.5 teeth/9) at 30°C was used. The experimental results are shown in Table 3 (example of the present invention) and Table 4 (
Conventional example).

According to both tables, all of the conventional examples had scuffing at the welds, whereas the examples of the present invention had scuffing in Nos. 1 to 3. NO2
1, 22, and No. 30 to 332, which are located outside the range S shown in Figure 4, cause scuffing or damage to the peripheral edges of the four oil holding parts, but the above range S
Everything inside has a good lubrication effect (and no scuffing or destruction of the four parts occurs).

FIG. 6 shows a microscopic photograph of the surface of Invention Example N (+1/I) in Table 3 of -■1, magnified 50 times.

This photograph shows that the delta holding recesses have the same shape and are engraved in a uniform manner, and the portions between the recesses maintain a mirror surface.

Also, on the inner wall of the cylinder liner, No. 7, 15 of the third person mentioned above was installed.
, 17, and 18 were provided with 11 A-il holding recesses, and those subjected to the surface treatments of Δ, B, and C in Table 4 were tested for oil leakage.

The oil leakage dest l, J, st: 7 As shown in Fig. Yo, -Fka1. . 32wi13□i3. , I, 1. ) The cylinder liner 17 was fixed in the holder 16, and the surface roughness of the inner wall of the cylinder liner was measured. The surface finish and chrome plating layer are as shown in Table 6 below.

The engine used for the above endurance test is 1NO1KI FF1L equipped with Turbote 1 Fusiya! : +0Occ, the piston ring is the same as that used in the oil leak test above, and the experimental conditions were lead-free Solin and 'C full negative? ij (5000rpm) 11
I drove for 00 hours. The surface roughness was measured in the direction along the piston sliding direction of the inner wall of the cylinder liner corresponding to the top dead center of the piston. The results are shown in Table 6 and in Figures 0 to 12. Note that the magnification is 2000 times vertically and 2048 times horizontally. The average wear amount is also shown in Table 6.

According to the figure, in the case of a cylinder liner without chrome plating, the conventional example (Fig. 9 (a) → (+))) is (
, 1 crosshatching (Ill suddenly disappears and becomes a smooth surface, and snowing occurs partially, but the present invention example (Fig. 10 (a) → (b) ) After C moves to Des 1, the fi'i ratio of bA oil retaining recessed surface remains unchanged at 20% and the average wear amount is small.Also, the conventional example in which a chrome-plated cylinder liner is fitted is shown in Fig. 11 (a). )→
12 (a) → <b)
)) A similar tendency is observed with the oil holding recess. It can be seen that in both cases, the oil retaining recesses according to the present invention have the same cross-sectional shape and are carved at equal pitches.

[Brief explanation of the drawing]

Figures 1 to 4 illustrate embodiments of the present invention, Figure 1 is a #vLnJi side view of the cylinder block, Figure 2 is an enlarged sectional view of Figure 1 (31, Figure 3 is an enlarged sectional view of Figure 1, and Figure 3 is an A toe edging view). Fig. 14 shows the setting range of the oil holding recess by the method, Fig. 5 shows the actual wear test (9) Fig. 1, and Fig. 6 shows the actual A micrograph showing the gold-flexed silk weave on the base surface of the invention example, Figure i:+'7 shows the experimental apparatus for oil leaking dust, and Figure 8 shows the experimental results for oil leaking dust, Figure 5.] Figure 12 is an enlarged sectional view of the inner wall of the cylinder live due to durability rest, Figure 13 is a diagram showing the crosshatch shape, Figures 14 to 16 are equivalent to Figure 2 with conventional honing 1111 process, FIG. 17 is a diagram corresponding to FIG. 2 in which the conventional porous chrome metal 4:1 is placed in the same position. 3...Cylinder, 5...Oil holding recess. Figure 4 Area + (°l.) Figure 1 / Figure 2 Figure 7 Figure 8 o18 0 2 1- 6 8 10 12 14 H

Claims (2)

[Claims] (1) An engine cylinder characterized in that a plurality of four oil retaining portions each having a substantially U-shaped cross-sectional shape formed by the etching method are provided on the inner wall of the engine cylinder. (2) In Fig. 4, the area ratio of the holding recessed portion 71 is 10 to 50%, and the depth is 50 μm at the area ratio of 10% and the depth at the area ratio of 50%. 3
0μ point and below, and within the range on the straight ridge that connects the 10μ depth point that has an area ratio of 10% and the 3μ depth point that has an area ratio of 50%. A one-engine cylinder according to claim (1).