JPH04105665U - piston ring - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a piston ring with a uniform coating thickness even in a non-circular shape, such as an oval or ellipse, by adopting a film formation method using ion plating. do. [Structure] This is a structure in which a wear-resistant film 13 is provided on at least the outer peripheral surface of an oval or elliptical ring body 11 using an ion plating film forming device. As a film,
A metal evaporator is used, and titanium nitride, a composite of chromium and chromium nitride, or chromium nitride is used.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a piston ring for internal combustion engines, and more specifically, to an oval or elliptical piston ring. This invention relates to a piston ring having a shape corresponding to a cylinder with a shaped cross section.

0002

[Conventional technology]

In recent years, cylinders have become increasingly popular, especially in cylinders used in motorcycle engines. The cross-sectional shape is not circular as before, but is shaped into an oval or oval shape. Are known. In other words, the cylinder width is smaller than if it were circular, and the entire engine The purpose is to minimize the overhang of the vehicle body width when viewed from the body. Naturally, the shape of the piston ring also corresponds to this non-circular cylinder. It will be similar to this. Sliding parts such as piston rings require particularly wear resistance. Because of the requirements, the surface is treated with a film such as hard Cr (chromium) plating. It will be done. After the coating treatment, the surface of the piston ring is finished by lapping.

0003

[Problem that the idea aims to solve]

By the way, when the piston ring is non-circular, such as an oval, during coating treatment, The thickness of the film formed on the surface tends to be uneven compared to a regular circular one. Furthermore, it is difficult to uniformly wrap the product after treatment. Due to these circumstances, it is possible to form a wear-resistant film uniformly and without finishing processing. The PVD method (Physical Vaper Deposu ition Process) is known. Ion plating is included in this PVD method. There is a method of This ion plating method is a type of vacuum evaporation, and is currently , is becoming an extremely common surface treatment method for forming thick films. As an advantage of this are metal compounds such as metal carbides, metal nitrides, metal oxides, or their There are some points in which film treatment with composite materials is possible. Furthermore, from the coating formed by vacuum evaporation method, has much better adhesion to the base material, and the film formation rate is faster than that of the sputtering method. It has the advantage of being very fast. Therefore, the purpose of the present invention is to By doing this, we can provide piston rings with uniform coating thickness even if they are non-circular. There are many things.

0004

[Means to solve the problem]

The piston ring according to the present invention has at least an oval or oval ring body. A wear-resistant film is applied to the outer circumferential surface using an ion plating film forming device. be. A metal evaporation material is used for the film, and titanium nitride or chromium and metal are used as the film. A composite of chromium nitride or chromium nitride is used. The thickness of the film is 5 to 50 μm, Preferably it is 10 to 20 μm.

[0005]

[Effect]

By driving the holder, the ring body of the held adherend rotates. At this time, The rotating ring body is heated by the heater. An electron beam is emitted from the electron gun. It is taken out and irradiated onto the evaporator. With this ion plating film forming device, the sliding surface of the ring body is coated. Because the film is formed, the thickness of the film is uniform even if the ring body is non-circular. Service The top surface is also good, and lapping is not necessary after the film treatment.

[0006]

【Example】

Embodiments of the piston ring according to the present invention will be described below with reference to the drawings. 1 and 2 show an embodiment of a piston ring 10 having an oval shape. ring The main body 11 has an abutment part 12 on one side in the long axis direction of the oval shape, and the outer part of the ring main body 11 is A film 13 is formed on the peripheral surface. The thickness of the film 13 is preferably in the range of 5 to 50 μm. Preferably, the thickness is 10 to 20 μm.

[0007] FIG. 3 is an example of an ion plating apparatus for forming the film 13. The device is It has a vacuum chamber 20 which is depressurized by a vacuum pump, and inside this is a base material which is an adherend. The ring body 11 is rotatably held by a holder 22. Above the holder 22 A heater 23 is installed to heat the ring body 11 to a predetermined temperature. Also, A water-cooled copper crucible 24 is installed below the holder 22, and a coated metal (hereinafter referred to as 25 (referred to below as evaporation material) is accommodated. The evaporative material 25 mentioned here is in the embodiment. Titanium and chromium are used.

Furthermore, an HCD type electron gun 26 and an atmospheric gas (N ₂ gas) introduction pipe 27 are attached to the side wall of the vacuum chamber 20 . A focusing coil 28 is arranged above the crucible 24, and is configured so that the evaporating material 25 can be irradiated with the electron beam emitted from the electron gun 26 by the focusing coil 28.

Next, in the method of forming the coating 13 on the ring body 11 using the apparatus shown in FIG. 3, the ring body 11 of the adherend held by the holder 22 is rotated by the drive of the holder 22 . At this time, the rotating ring body 11 is heated by the heater 23. An electron beam is emitted from the electron gun 26 and is irradiated onto the evaporation material 25 described above. The electron beam has a low voltage and a large current, and by lowering the current of the focusing coil 28, the heating surface area of the evaporator 25 can be increased, and a large amount of sublimable metal can be evaporated. In addition, since the electron beam operates in a low vacuum of 10 ^-2 torr to ^{10 -4} torr, it continues to operate normally even in splashes that are likely to occur when powder or small particles are used as the evaporator 25. Does not cause any problems.

The following is an example of film treatment conditions.・Heating temperature of base material ring body 400℃ ・Electron beam output 38V (volt) 500A (ampere) ・Crucible diameter φ70 depth 100mm ・Nitrogen gas partial pressure 5×10 ⁴ to 5×10 ³ torr ・Evaporation material Titanium metal Alternatively, metal chromium (small lumps) or commercially available small pieces of electrolytic chromium can also be used. Processing time: 30 minutes to 120 minutes.

[0011] Note that the above is an example in which the coating 13 is formed only on the outer peripheral surface of the ring body 11. However, it is also possible to form a film on both sides of the ring body 11, including the inner peripheral surface. .

0012

[Effect of the idea]

The piston ring according to this invention is produced using an ion plating film forming device. Because a film is formed on the surface of the ring body, the shape of the ring body is non-circular, such as an oval. Even if there is, the film thickness is uniform, and there is no need for lapping after treatment.

[Brief explanation of drawings]

[Fig. 1] A perspective view of an embodiment of a non-circular piston ring according to the present invention.

[Fig. 2] Partial cross-sectional view of an embodiment of a non-circular piston ring according to the present invention

[Figure 3] HC forming a film on the piston ring of the example
Schematic diagram of D ion plating device

[Explanation of symbols]

11...Ring body, 13...Coating, 20...Ion plating film forming device, 21...Vacuum chamber, 22...
Base material (ring body) holder, 23...Heater, 24...
Water-cooled copper crucible, 25... Evaporation material, 26... HCD electron beam gun, 27... Atmosphere gas introduction tube, 28... Focusing coil

Continuation of front page (72) Creator Masanori Oya Rike Co., Ltd. 1-37 Hokutocho, Kashiwazaki City, Niigata Prefecture Inside Kashiwazaki Office

Claims (2)

[Scope of utility model registration request] 1. A piston ring characterized in that a wear-resistant coating is provided on at least the outer peripheral surface of an oval or elliptical ring body using an ion plating coating forming device. 2. The piston ring according to claim 1, wherein the coating is titanium nitride, a composite of chromium and chromium nitride, or chromium nitride.