JPS59217059A - Piston ring and manufacturing method thereof - Google Patents

Abstract

PURPOSE:To provide a piston ring which is thin and good in a seal characteristic of a joint portion by stacking two sheets of steel rings having a stepped joint end portion and securing the whole periphery thereof. CONSTITUTION:A step portion having a projecting portion 3 on the inner periphery side is formed on the right joint end portion of an upper ring 2, and a step portion having a projecting portion 4 on the outer periphery side is formed on the left joint end portion. A step portion having a projecting portion 6 on the outer peripheral side is formed on the right joint end portion of a lower ring 5, and a step portion having a projecting portion 7 on the inner peripheral side is formed on the left joint end portion of the lower ring 5. The upper and lower rings 2, 5 are put one over another, with the respective end surfaces of the projecting portions 4, 7 shifted from each other, and adhered to be united in a body extending over the substantially total peripheries of the upper and lower rings 2, 5. Thus, two sheets of thin steel rings can be put one over another to manufacture a piston ring, and a good seal characteristic of a joint portion as a piston ring can be attained.

Description

[Detailed description of the invention] The present invention relates to a piston ring and a method for manufacturing the same.

The piston ring fits into a ring groove provided on the outer circumferential wall of the piston and follows the inner circumferential wall of the cylinder to completely prevent leakage of working fluid from one side of the piston ring to the other and vice versa. It is something. Taking an internal combustion engine as an example, it prevents high-pressure gas from leaking from the combustion chamber to the crank chamber (preventing proby) and prevents oil from the crank chamber from rising into the combustion chamber, increasing oil consumption. It has the effect of Various attempts have been made to improve the shape of the piston ring in order to fulfill this function, and one example is an attempt to change the shape of the abutment. For example, as shown in FIG. 7, a notch 23 is provided at the outer peripheral side and lower corner of one joint end 21 of the piston ring, and a notch 23 is provided at a position opposite to the notch on the other joint end 22. A piston ring having a so-called double angle joint structure has been proposed, which has a protrusion 24 having a shape corresponding to the shape of the notch.

This piston/ring having a double angle structure for all the joint parts has the protruding part 24 inserted into the notch 23 at the other joint end when it is installed.
Leakage of the working fluid from the joint is effectively prevented and the sealing properties are good.

However, in recent years, especially in internal combustion engines, there has been a tendency to use very thin piston rings due to the need to reduce engine friction loss and overall oil consumption. In the case of piston rings, it is extremely difficult to process the abutment into the above-mentioned double angle structure, and it is actually impossible to manufacture.

In view of the above, the present invention has been made for the purpose of providing a piston ring that is thin and has good sealing properties.

According to the present invention, two steel rings having a plate thickness of 0.3 to 1.5 and having a stepped structure in the radial direction at the end of the joint, at least the end surface located on the outer peripheral side of the stepped structure. A piston ring is provided, which is stacked one on top of the other in a staggered state, is fixed and integrated over substantially the entire circumference, and has a wear-resistant surface layer on the outer circumferential sliding surface.

Furthermore, according to the present invention, steps are provided in the radial direction at the abutment ends of the steel rings with a plate thickness of 0.3 to 1.5 mm, and dams are formed at the top and bottom of the outer peripheral surface of the ring. The above-mentioned steel rings are stacked one on top of the other in a state where at least the end faces located on the outer peripheral side of the joint end faces are completely shifted, and both the above-mentioned steel rings are fixed and integrated over the entire y circumference. There is provided a method for manufacturing a piston ring, characterized in that the groove between the plates is subjected to wear-resistant thermal spraying treatment, and then the outer periphery is polished.

Embodiments of the invention will be described with reference to the accompanying drawings.

Please refer to FIG. A radially stepped gold film is applied to the joint end of a steel ring with a plate thickness of 0.3 to 1.5 mm. A step portion having a protrusion 3 on the inner circumferential side is formed at the right side abutment end of the upper ring 2, and a step portion having a protrusion 4 on the outer circumference side is entirely formed at the left side abutment end. A step portion having a protrusion 6 on the outer circumferential side is formed at the right abutment end of the lower ring 5, and a step portion having a protrusion 7 on the inner circumference side is formed at the left abutment end of the lower ring 5. Such stepped upper and lower rings 2.5 are formed by, for example, press cutting. The end surfaces of the respective protrusions of the upper and lower rings are stacked one on top of the other with their edges shifted, so that the inner circumferential side surface 8 of the left upper protruding portion 4 is in sliding contact with the outer circumferential side surface 9 of the right upper protruding portion 3, and the inner circumferential side surface 1 of the right upper protruding portion 6゜ is in sliding contact with the outer circumferential side surface 11 of the right upper protruding part T, and the lower wall surface 12 of the left upper protruding part 4 is in sliding contact with the wall surface 13 of the right upper protruding part 6cv-. Glue the entire circumference to form an integral ring.

When chrome plating is formed on the outer peripheral surface of the ring, the entire outer peripheral surface is chromium plated before the upper and lower rings 2 and 50 are stacked and integrated, and then the upper and lower rings are bonded and integrated.

In the example shown in FIG. 2, the outer peripheral surfaces of the upper and lower rings 2 and 5 are entirely formed with spaced banks 14, and grooves 15 are entirely formed therebetween. This embankment 14 and groove 15 are connected to the upper and lower rings 2
, 5 when forming the stepped structure, or may be formed in advance on the strip machine before forming the ring.

After the above-mentioned upper and lower rings 2 and 5 are bonded and integrated, a wear-resistant thermal spraying treatment is applied to the ring 615, and then the outer circumferential surface is polished to form a wear-resistant surface layer on the outer circumferential surface of the ring.

Separately from the example shown in Fig. 2, as shown in Fig. 3, the central bank where the upper and lower rings overlap is removed so that a portion remains at the end, and the upper and lower grooves 15 are fully connected. In this state, the wire grooves 15 are thermally sprayed for wear resistance, and then the outer periphery is polished, thereby making it possible to fully utilize the upper and lower continuous wear-resistant surface layers.

In the piston ring described above, even if the working fluid on the upper side enters the upper side abutment part 16, this working fluid does not slide between the inner circumferential side surface 8 of the left upper protrusion part 4 and the outer circumferential side face 9 of the right upper protrusion part 3. contact, sliding contact between the outer circumferential surface 11 of the right upper protrusion 7 and the inner circumferential surface 10 of the right upper protrusion 6, and sliding contact between the lower wall surface 12 of the left upper protrusion 4 and the upper wall surface 13 of the right upper protrusion 6. Since the lower ring 5 contacts the bottom wall of the ring groove, there is very little leakage of the piston ring downward. Furthermore, even if the working fluid on the upper side of the piston ring enters the upper abutment 17, the piston ring outer peripheral surface and the cylinder inner wall surface slide into contact and the left upper protrusion 4
Due to the sliding contact between the lower wall surface 12 of the piston ring and the soil wall surface 13 of the right upper protrusion 6, leakage to the lower side of the piston ring is extremely rare. Furthermore, the working fluid below the piston ring is
Even when the piston ring enters the joint 18, there is almost no upward leakage of the piston ring due to the sliding contact between the outer circumferential surface 11 of the right upper protrusion 7 and the inner circumferential surface 10 of the right upper protrusion 6. Another example of the invention is shown. The upper tone ring of the piston ring shown in FIG. 6 is shown in FIG. 4, and the lower tone ring is shown in FIG.

A step portion having a protrusion 3' on the inner circumferential side is entirely formed at the right joint end of the upper ring 2', and a step portion having a protrusion 4' on the outer circumference is formed at the left joint end.

A step part having a protrusion 6' on the inner circumferential side is entirely formed at the right joint end of the lower ring 5', and a step part having a protrusion 7' on the outer circumferential side is formed at the left joint end.

The width t1 of the upper protrusion 3' and the width t2 of the lower protrusion γ' are made to be different dimensions.

The upper and lower rings 2', 5't thus formed are shaped so that the right protrusion 3' of the upper ring 2' protrudes from the right protrusion 6' of the lower ring 5', and the left protrusion of the upper ring 2' A state in which the left protruding part T' of the lower ring 5' protrudes from the part 4'. On the earthen wall surface of the ring 5' and on the left side protrusion 7' of the lower ring 5'
It is slidably connected to the lower wall surface of the ffi upper ring 2'. As a result,
In sliding contact with the inner and outer circumferential surfaces 8' and 9' of the respective protrusions 3' and 4' of the upper ring, and in sliding contact with the inner and outer circumferential surfaces 10' and 11' of the respective protrusions 6' and 7' of the lower ring 5'. In addition, the right seat surface 19
comes into sliding contact with the lower wall surface of the left side protrusion 4' of the upper ring 2. Thus, leakage of working fluid from one piston ring to the other is prevented, similar to the example shown in FIG.

The outer peripheral surface of the piston ring shown in FIG. 6 is chromium plated. Instead of the chromium plating treatment, the embankment shown in FIG. 2 or 3 can be formed on the outer peripheral surface, and the entire wear-resistant surface layer can be formed by performing the wear-resistant thermal spraying treatment and the outer periphery polishing.

As evidenced by the above-mentioned embodiments, the piston ring of the present invention consists of two thin steel rings with a plate thickness of 0.3 to 1.5 cm, each of which has a step + J structure at the joint end. It is manufactured by shifting the parts, overlapping them, and fixing them over substantially the entire circumference.

Therefore, it is possible to easily obtain a piston ring metal that is thin and has good sealing properties at the abutment portion.

Here, the steel ring can be fixed by adhesion, brazing, spot welding, or the like.

[Brief explanation of the drawing]

Fig. 1 is a partial perspective view of a piston ring according to an example of this invention. Fig. 2 is a partial perspective view of an example in which a bank is provided on the outer peripheral surface. Fig. 3 is a partial perspective view of an example in which the central part of the bank is removed. FIG. 4 is a partial plan view showing another example of the upper ring, FIG. 5 is a partial plan view of the lower ring, and FIG. A perspective view, FIG. 7 is a partial perspective view showing a conventional example. In the diagram: 1... piston ring, 2. z...upper ring, 5.5'...lower ring. Agent Patent Attorney Hideaki Kuwahara Figure 6 Figure 7 1

Claims (6)

[Claims] (1) Plate thickness 0.0mm with stepped structure in the radial direction at the end of the joint.
Two steel rings of 3 to 1.5 rings are stacked one on top of the other with the end surfaces located at least on the outer circumferential side of the stepped structure completely shifted, and are fixed substantially over the entire circumference to form an integral body. A piston ring characterized by having a wear-resistant surface layer on the outer circumferential sliding surface. (2) The piston according to item (1), characterized in that the steel ring has banks spaced apart above and below the outer peripheral surface, and a wear-resistant surface layer is provided in the groove formed between the plates. ring. (3) A groove formed by removing the upper mill where the upper steel ring mill and the earth embankment of the lower steel ring overlap is filled with a wear-resistant surface layer.
Piston ring described in section 2). (4) Providing a step in the radial direction at the joint end of a steel ring with a plate thickness of 0.3 to 1.5 mm; applying wear-resistant treatment to the outer peripheral surface of the steel ring; The two steel rings having a chromium plating layer are stacked one on top of the other with the end faces located at least on the outer circumferential side of the abutting portions completely shifted, and both the steel rings are fixed together over the entire circumference. A method for manufacturing piston rings, which comprises: (5) Providing a step in the radial direction at the joint end of a steel ring having a plate thickness of 0.3 to 1.5 mm, and forming dams spaced apart above and below the outer peripheral surface of the ring; Two steel rings are stacked one on top of the other with the end faces located at least on the outer periphery side of the joint portions being shifted, and both of the steel rings are fixed together over the entire circumference of the ring, and the plate is integrated. A method for producing piston rings characterized by applying wear-resistant thermal spraying to the grooves between the piston rings and then polishing the outer periphery. (6) A wear-resistant thermal spraying treatment is applied to the grooves formed by removing the downward slope of the upper ring and the overlapping metal of the lower ring, and the vicinity of the abutment, and the outer periphery is polished. The method for producing a piston ring according to item (5), characterized in that: