JP2003010937A - Manufacturing apparatus for piston ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing apparatus for a piston ring having no shear drop on a wire rod forming a piston ring and not necessitating subsequent processing after cutting. SOLUTION: The manufacturing apparatus 1 for a piston ring is comprised of a group of feeding rollers 10, a group of curling rollers 20, and a cutting portion 30. The group of the feeding rollers 10 provides a feeding roller 11 feeding the wire rod 2 in the apparatus 1. The group of the curling rollers 20 provides a first roller 21 and third roller 23 and also provides a second roller 22 with a diameter greater than those of the rollers 21 and 23, and the straightened wire rod 2 is curled in a circular shape with a desired diameter. An direct distance between a rotary axis 21B of the first roller 21 and a rotary axis 22B of the second roller 22 is equal to a direct distance between the rotary axis 22B of the second roller 22 and the rotary axis 23B of the third roller 23. The curled wire rod 2 is cut in the cutting portion 30 by means of a grinding wheel 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piston ring manufacturing apparatus, and more particularly to a method for curling a piston rod wire rod, and then cutting the piston ring rod wire without shearing to form a single piston ring rod. The present invention relates to a piston ring manufacturing apparatus for manufacturing piston rings.

[0002]

2. Description of the Related Art Conventionally, there is known an apparatus for manufacturing a piston ring one by one by curling a wire rod for one piston ring and then cutting the wire rod. In this device, a linear wire is curled by a plurality of roller groups, and then the wire is sheared by a cutting blade.

In Japanese Patent Laid-Open No. 11-129049, a linear wire is curled by first to third rollers,
An apparatus 101 for manufacturing a piston ring by shearing with a cutting blade after forming a strained circular ring having a desired strain by a fourth roller is described. This device 101, as shown in FIG.
Six feed rollers 111 for feeding 2 are provided. The feed roller 111 is provided on the most upstream side in the feeding direction of the wire rod 102. Wire rod 10 sent
2 has a rectangular cross section, and the side surface of the wire rod 102 includes an upper surface 102A, a lower surface (not shown), and one side surface 102B.
And another side surface 102C facing one side surface. The wire rod 102 is configured to be fed into the apparatus by rotating the feed roller 111.

A wire 10 is provided on the downstream side of the feed roller 111.
The first roller 121 is provided so as to be able to contact the one side surface 102B of the second roller 102. On the downstream side of the first roller 121,
A second roller 122 having a diameter smaller than that of the first roller 121 and capable of contacting the other side surface 102C of the wire rod 102 is provided. The wire rod 10 is provided downstream of the second roller 122.
A third roller 123 having a diameter larger than that of the second roller 122 is provided so as to be able to contact the one side surface 10B of the second roller 122. The distance between the rotation shaft 121B of the first roller 121 and the rotation shaft 122B of the second roller 122 is based on a virtual straight line, and the rotation shaft 122B of the second roller 122 and the third roller 1
It is shorter than the distance between the rotary shaft 123 and the rotary shaft 123B. More specifically, in FIG. 2, the length b is shorter than the length a. The linear wire 102 can be curled into a substantially circular shape by contacting the wire 102 with the first to third rollers 121, 122, 123. Further, when the wire rod 102 is cut by the cutting blade 133 described later, the wire rod 102 is cut by shearing, so that stress acts on the wire rod 102 toward the upstream side in the feeding direction of the wire rod 102. At this time, if the first to third rollers 121, 122, 123 remain in contact with the wire rod 102, the first to third rollers 121, 122, 1
Since the wire rod 102 may be deformed due to the stress between 23, when the wire rod 102 is cut, the first to third
The rollers 121, 122, and 123 are configured to be separated from the wire rod 102.

A fourth roller 140, which further deforms the curled wire 102 into a strained circular ring, is provided downstream of the third roller 123 so as to be able to contact the other side surface of the wire 102. The fourth roller 140 is formed of the wire 102.
The wire rod 102 can be formed into a desired strained circular ring by moving the wire rod 102 curled in a substantially circular shape in a substantially radial direction by NC control when the wire rod 102 is fed.

A cutting blade 13 is provided downstream of the fourth roller 140.
3 is provided, and the wire rod 102 is cut by shearing to form one piston ring. In cutting the wire rod 102 when manufacturing piston rings having different diameters, it is necessary to make the cutting blade 133 perpendicular to the feeding direction of the wire rod 102, so that the angle of the cutting blade 133 in the shearing direction can be adjusted. Is configured.

[0007]

However, in the conventional piston ring manufacturing apparatus, the cutting of the wire 102 is performed by the cutting blade 1.
Since it was carried out by shearing by 33, sagging occurred at the abutment portion where the wire 102 was cut. Therefore, in order to commercialize the product, it was necessary to remove the sagging portion by processing. More specifically, it is necessary to machine from the end face of the abutment part or to machine the dimension between the upper surface and the lower surface of the piston ring, that is, the so-called width dimension (h ₁ ) to be appropriate. It was

The first to third rollers 121, 122, 1
After performing one process for curling the wire rod 102 by 23, feeding of the wire rod 102 is stopped, and then the first to third rollers 121, 122, 123 are separated from the wire rod 102, and cutting is performed. If the wire rod 102 is cut without separating the first to third rollers 121, 122, 123 from the wire rod 102, the first to third rollers 121, 122, 122, while the feeding of the wire rod 102 is stopped.
When the wire rod 102 is in contact with 123, the wire rod 102 curled into a desired shape is deformed.
Further, since the wire rod 102 is cut by shearing, stress is generated in the direction opposite to the feeding direction of the wire rod 102 due to the impact force at the time of cutting, but at this time, the first to third rollers 121, 122, When the wire rod 102 is in contact with 123, the stress causes the wire rod 102 curled into a desired shape to be deformed. Therefore, in order to prevent the wire rod 102 from being deformed, as described above, the piston link is manufactured so that the first to third rolls 121, 122, 123 can be separated from the wire rod 102 when the wire rod 102 is cut. The configuration of the device has become an essential requirement, and the configuration of the device has become complicated.

When the diameter of the piston ring to be manufactured is to be changed, it is necessary to make the angle of the cutting blade 133 in the shearing direction perpendicular to the wire rod 102 each time as described above. There is. The cutting blade 133 for cutting the wire 102 is composed of an upper cutting blade and a lower cutting blade, and the cutting angle cannot be changed.
It was necessary to move 2 to adjust the cutting angle.

In the conventional piston ring manufacturing apparatus, the curling process of the wire rod 102 and the subsequent wire rod 102 are performed.
In order to alternately perform the cutting process of 1., compared with other types of devices, for example, a device that curls wires in a spring shape and then cuts them together to produce multiple piston rings at one time, Since it takes time to manufacture the piston ring, the more efficient cutting has been desired in the manufacturing method.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a piston ring manufacturing apparatus that does not cause sagging in a wire forming a piston ring and requires almost no processing after cutting.

[0012]

To achieve the above object, the present invention relates to a feed roller for feeding a piston ring wire having an upper surface, a lower surface, one side surface and the other side surface in one direction, and the feed roller. A first roller movably arranged on the downstream side of the first roller and capable of contacting the one side surface; a second roller movably arranged on the downstream side of the first roller and capable of contacting the other side surface; A curling roller group for plastically deforming the wire rod to a constant curvature, which includes a third roller movably arranged on the downstream side of the two rollers and capable of contacting the one side surface, and a curling roller group which is deformed to a constant curvature. In order to form the wire rod into a distorted circular ring, a fourth roller disposed downstream of the curling roller group and movably arranged so as to come into contact with the other side surface, and the distorted circular ring. In order to cut the wire rod in the substantially radial direction of the strained circular ring, And a cutting means arranged on the downstream side of the four rollers, the diameter of the second roller is set to be larger than the diameter of the first and third rollers, and the cutting means is An upper clamp and a lower clamp for abutting the upper surface and the lower surface of the wire rod to clamp the wire rod, and an upper clamp and a lower clamp for cutting the wire rod clamped by the upper clamp and the lower clamp. A grindstone movable in a direction connecting the upper surface and the lower surface, and the upper clamp, the lower clamp, and the grindstone are integrally movable in the radial direction of the strained circular ring and angled with respect to the one direction. An adjustable piston ring manufacturing apparatus is provided.

Here, the distance between the rotation axis of the second roller and the rotation axis of the first roller and the distance between the rotation axis of the second roller and the rotation axis of the third roller may be equal to each other. preferable.

Further, according to the present invention, a feed roller for feeding a piston ring wire having an upper surface, a lower surface, one side surface and the other side surface in one direction and a movably arranged downstream side of the feed roller. A first roller that can come into contact with the second roller, a second roller that is movably arranged downstream of the first roller and can come into contact with the other side surface, and a second roller that is movably arranged downstream of the second roller. A curling roller group for plastically deforming the wire rod to a constant curvature, which includes a third roller capable of contacting one side surface, and a wire rod deformed to the constant curvature to form a strained circular ring, A fourth roller, which is arranged downstream of the curling roller group and is movable so as to be able to contact the other side surface, and a wire formed in the strained circular ring, which is cut in a substantially radial direction of the strained circular ring. Cutting means arranged downstream of the fourth roller for Apparatus for manufacturing a piston ring with, said second roller has a diameter the first and third
It is set to be larger than the diameter of the roller, the cutting means is constituted by a laser cutting device, and the laser cutting device is capable of moving the laser irradiation direction in the radial direction of the strained circular ring and adjusting the angle with respect to the one direction. The manufacturing apparatus of the piston ring provided in this is provided.

Here, the distance between the rotation axis of the second roller and the rotation axis of the first roller and the distance between the rotation axis of the second roller and the rotation axis of the third roller may be equal to each other. preferable.

According to the present invention, a feed roller for feeding a piston ring wire having an upper surface, a lower surface, one side surface and another side surface in one direction, and a movably arranged downstream side of the feed roller. A first roller that can come into contact with the second roller, a second roller that is movably arranged downstream of the first roller and can come into contact with the other side surface, and a second roller that is movably arranged downstream of the second roller. A curling roller group for plastically deforming the wire rod to a constant curvature, which includes a third roller capable of contacting one side surface, and a wire rod deformed to the constant curvature to form a strained circular ring, A fourth roller, which is arranged downstream of the curling roller group and is movable so as to be able to contact the other side surface, and a wire formed in the strained circular ring, which is cut in a substantially radial direction of the strained circular ring. Cutting means arranged downstream of the fourth roller for Apparatus for manufacturing a piston ring with, said second roller has a diameter the first and third
The cutting means is set to be larger than the diameter of the roller, and the cutting means is constituted by a water jet cutting device, and the water jet cutting device has a jet jet direction movable in the radial direction of the strained circular ring and an angle with respect to the one direction. An adjustable piston ring manufacturing apparatus is provided.

Here, the distance between the rotation axis of the second roller and the rotation axis of the first roller and the distance between the rotation axis of the second roller and the rotation axis of the third roller may be equal to each other. preferable.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION A piston ring manufacturing apparatus 1 according to an embodiment of the present invention will be described with reference to FIG.
In the piston ring manufacturing apparatus 1, the feed roller group 10 for feeding the wire 2 into the piston ring manufacturing apparatus, and the wire 2 fed by the feed roller group 10 are curled into a circle having a desired diameter. A curling roller group 20 for cutting and a cutting portion 30 for cutting the curled wire 2 are provided.

The wire 2 fed by the feed roller group 10 has a linear shape in the feed direction, and a cross section perpendicular to the feed direction has a rectangular shape. That is, the wire 2 has a quadrangular prism shape that is long in the feeding direction, and its four side surfaces form an upper surface 2A, a lower surface (not shown), one side surface 2B, and the other side surface 2C.

The feed roller group 10 is composed of feed rollers 11 provided so as to face each other. Each feed roller 1
The rotating shafts 11A of No. 1 have a positional relationship parallel to each other and are oriented in the horizontal direction. In addition, since the feed rollers 11 and 11 facing each other are positioned vertically above and below, the linear wire 2 has its upper surface 2A and lower surface abutted on the peripheral surfaces 11B of the rollers 11 and 11 forming each pair. While being sandwiched by the rollers 11 and 11 from above and below,
It is configured to be fed into the piston ring manufacturing apparatus 1 by the rotation of the feed rollers 11, 11.

The curling roller group 20 is composed of a first roller 21, a second roller 22 and a third roller 23. The rotating shafts 21B, 22B and 23B of the first to third rollers 21, 22 and 23 are located in parallel with each other. The first roller 21 is provided on the most upstream side in the feed direction of the wire rod 2 fed from the feed roller group 10.
Subsequently, the second roller 22 and the third roller 23 are provided in this order toward the downstream side. In addition, the first roller 2
The peripheral surface 21A of No. 1 is arranged so as to contact one side surface 2B of the wire rod 2, and the peripheral surface 22A of the second roller 22 is
It is arranged so as to contact the other side surface 2C of the wire rod 2, and the peripheral surface 23A of the third roller 23 is arranged so as to contact one side surface 2B of the wire rod 2. First roller 21
Is the same as the diameter of the third roller 23, and the diameter of the second roller 22 is larger than the diameters of the first roller 21 and the third roller 23. More specifically, the diameter of the second roller 22 is 2/3 of the diameter of the manufactured piston ring, that is, the winding outer diameter. Therefore, the other side surface 2C of the wire rod 2
It is possible to set the area of the portion where the and the peripheral surface 22A of the second roller 22 are in contact with each other to an optimum value. Further, on the peripheral surfaces 21A, 22A, 23A of the rollers 21, 22, 23, recesses (not shown) are formed inward in the radial direction of the rollers 21, 22, 23, so that the wire 2 is stable. The rollers 21, 22, 23 are configured to come into contact with the peripheral surfaces 21A, 22A, 23A of the rollers 21, 22, 23, respectively.

The rotary shaft 21B of the first roller 21 and the second
The linear distance between the rotary shaft 22B of the roller 22 is the rotary shaft 22B of the second roller 22 and the rotary shaft 23 of the third roller 23.
Equal to the straight line distance to B. In FIG. 1, the first roller 21 is movable in the direction A perpendicular to the feeding direction of the wire 2 at the position of the feeding roller group 10, and the second roller 22
Is configured to be movable in the feed direction B of the wire 2 at the position of the feed roller group 10. The third roller 23 is configured to be movable in the feed direction C of the wire rod at the position of the feed roller group 10 and the direction D perpendicular to the feed direction.
As described above, since the first to third rollers 21, 22, and 23 are configured to be movable, the first to third rollers 21, 22, and 23 are moved to appropriate positions, and the piston having a desired diameter is obtained. The ring can be manufactured. First to third rollers 2
1, 22, and 23 are the second rolls at positions separated from the second roll 22 due to the stress that the linear wire rod 2 receives from the peripheral surfaces 11A, 22A, and 23A of the first to third rollers 21, 22, and 23. It is configured to be curled in a circular shape such that 22 is wound.

On the downstream side of the curling roller group 20 in the feed direction of the wire rod 2, there is provided a fourth roller 40 used when the piston ring to be manufactured has an elliptical shape and is not a perfect circle. Peripheral surface 40A of the fourth roller 40
Is configured to be able to contact the other side surface 2C of the wire rod 2. The fourth roller 40 is a curling roller group 1
The wire rod 2 curled into a circular shape by 0 is movable in the radial direction E, and this movement is performed by NC control. When the curled wire 2 is being fed, the fourth roller 40 is moved at a desired timing in the radial direction of the curled wire 2 in a circular shape and presses the wire 2, thereby making the wire 2 oval. It is configured so that it can be transformed into a shape or the like.

A cutting portion 30 is provided on the downstream side of the fourth roller 40 in the feeding direction of the wire 2. The cutting unit 30
Lower clamp 31 and upper clamp 32 forming a clamp base
And a grindstone 33. Lower clamp 31
Is arranged at a position where the curled wire 2 can pass slightly above the lower clamp 31, and the upper clamp 32 is provided vertically above the lower clamp 31. The lower clamp 31 is configured to be immovable in the vertical vertical direction, and the upper clamp 32 is configured to be movable in the vertical vertical direction. The upper clamp 32 moves vertically downward, the upper clamp 32 abuts on the upper surface 2A of the wire rod 2, the lower clamp 31 abuts on the lower surface of the wire rod 2, and the wire rod 2 is placed between the upper clamp 32 and the lower clamp. It is configured to be held between. In addition, the lower clamp 31 has a concave portion 3 in the radial direction of the circularly curled wire 2.
1a is formed, and the recess 31a reaches a position vertically below the wire 2 passing above the lower clamp 31.

The grindstone 33 has a thin disk shape, and the shaft 3
It is configured to be rotatable around 3A. Whetstone 33
The radial direction of is perpendicular to the feed direction of the wire rod 2 at the position of the cutting portion 30, and the grindstone 33 is movable in the radial direction F of the wire rod 2 curled in a circular shape in FIG. A part of the grindstone 33 is configured to pass through the inside of the recess 31a described above while rotating. The grindstone 33 is also configured to be movable in the vertical vertical direction, that is, in the direction connecting the upper surface 2A and the lower surface of the wire 2. Further, the grindstone 33 is integrally formed with the lower clamp 31 and the upper clamp 32, and is configured to be rotatable about a position separated from the wire 2 with respect to the shaft 33A, that is, swingable in the direction G. Since the grindstone 33 is constructed so that it can be swung and moved as a whole together with the lower clamp 31 and the upper clamp 32, the radial direction of the grindstone 33 can be extremely easily changed even when manufacturing piston rings having different diameters. It can be oriented perpendicular to the feeding direction of the wire 2 in the cutting part 30.

In manufacturing the piston ring, first,
The first to third rollers 21 to 23 are arranged in a positional relationship suitable for manufacturing a piston ring having a desired diameter. However, the distance between the shaft 21B of the first roller 21 and the shaft 22B of the second roller 22 and the distance between the shaft 22B of the second roller 22 and the shaft 23B of the third roller 23 are always as described above. Try to be the same. Next, the radial angle of the grindstone 33 is
The grindstone 33 is adjusted to be perpendicular to the feed direction of the wire 2 at the position. Further, the grindstone 33 is moved to the lowermost portion in the vertical direction. Also, an NC program for performing NC control for setting a desired strain ring is set.

Next, the linear wire 2 is fed to the feed roller 11. The wire 2 sandwiched between the opposing feed rollers 11 and 11 is fed to the curling roller group 20 by the rotation of the feed rollers 11 and 11. In the curling roller group 20, first, one side surface 2B of the sent wire rod 2 abuts on the peripheral surface 21A of the first roller 21, and then the other side surface 2C of the wire rod 2 surrounds the second roller 22. Abut the surface 22A,
Then, the one side surface 2B of the wire rod 2 is brought into contact with the peripheral surface 23A of the third roller 23, whereby the wire rod 2 is curled into a circular shape having a desired diameter.

The curled wire 2 is attached to the fourth roller 4
0, and the other side surface 2C is the peripheral surface 40 of the fourth roller 40.
Contact A. At this time, the fourth roller 40 is deformed into a desired strained circular ring by moving the fourth roller 40 in the radial direction of the curled circular wire 2 at a desired timing under NC control.

Then, the wire 2 is continuously fed and the cutting portion 3
0, the wire rod 2 is urged vertically upward by an urging member (not shown), and the wire rod 2 is superposed on the wire rod 2 sent from the feed roller 11 later, and again curling roller portion 20 and the fourth roller. It reaches a cutting part through 40. At this point, the feeding of the wire rod 2 is stopped without separating the first to third rollers 21, 22, 23 from the wire rod 2, and the upper clamp 32 is moved vertically downward to move the wire rod 2 into the upper clamp 32 and the lower clamp 31. Sandwich between. At this time, the wire rod 2 is in a state of drawing a circle around the cutting portion 30 as a starting point, which corresponds to one piston ring. Then, the grindstone 33 is moved vertically upward and applied to the wire rod 2, and the wire rod 2 is cut to manufacture a piston ring.

Since the cutting method using a grindstone is used to cut the wire rod 2, no shearing force acts on the wire rod 2 and the cut surface of the wire rod 2 does not sag. For this reason, finishing of the cut surface, which becomes the abutment surface after cutting, can be made easier or unnecessary. Further, the force acting in the direction opposite to the feeding direction of the wire rod 2, that is, the force acting in the curling direction of the wire rod at the time of cutting, which is caused by the cutting by shearing at the time of cutting, can be made extremely small. Therefore, it is not necessary to separate the curling roller group 20 from the wire rod 2 at the time of cutting, and the process can be simplified.

Further, since the diameter of the second roller 22 is made larger than the diameter of the first roller 21 and the third roller 23, these rollers 21, 22, 23 are located on one side surface 2B of the wire 2. The area in contact with the side surface 2C can be increased, and the curling roller group 20 is kept in contact with the wire rod 2 at the time of cutting, so that the wire rod 2 extending between the first roller 21 and the second roller 22 can be formed. , The second roller 2
Since the free behavior of the wire rod 2 extending between the second roller 3 and the third roller 23 is further restricted, unexpected and excessive deformation of the wire rod 2 can be effectively prevented.

The piston ring manufacturing apparatus according to the present invention is not limited to the above-mentioned embodiment, and various modifications and improvements can be made within the scope of the claims. For example,
Although the grindstone 33 is used as the cutting means in the above-described embodiment, other cutting means that does not rely on shearing, such as a laser cutting machine or a water jet cutting machine, may be used instead of the grinding stone 33. In these cases, the laser irradiation direction of the laser cutting device and the jet injection direction of the water jet cutting device are provided so as to be movable in the radial direction of the strained circular ring and adjustable in angle with respect to the feeding direction of the wire rod by the feed roller. There is. Further, when the cutting ability of the laser cutter or the water jet cutter is high, the upper clamp 32 and the lower clamp 31 can be omitted.

Further, in the above-described embodiment, the first to fourth rollers 21, 22, 23, 40 are brought into contact with the wire 2 during cutting as well as during curling, and the operation of the machine as a whole process is performed. Is simplified, but if necessary,
The first to fourth rollers 21, 22, 23, 40 may be separated from the wire 2 at the time of cutting.

In the above-described embodiment, the strained circular ring is manufactured by controlling the NC of the fourth roller 40, but a circular piston ring may be manufactured without performing the NC control.

[0035]

According to the piston ring manufacturing apparatus of the first, third, and fifth aspects, since the cutting is performed by a grindstone, a laser, or a water jet, a shearing force does not act on the wire and the cut surface is sagging. And the finishing process of the abutment surface after cutting becomes easier or unnecessary.

Further, contrary to the cutting by shearing, the force generated in the curling direction of the wire rod during cutting becomes extremely small, so that it is not necessary to separate the curling roller from the wire rod during cutting, and the process is simplified. To be done.

Further, since the diameter of the second roller is made larger than the diameter of the first roller and the third roller, the area of contact with the side surface of the wire can be increased, and the curling roller can be contacted with the wire at the time of cutting. In addition to keeping them in contact with each other, the free behavior of the wire rod extending between the first roller and the second roller and the wire rod extending between the second roller and the third roller is further restricted, so that the wire rod may be unexpectedly moved. Excessive deformation can be effectively prevented.

According to the piston ring manufacturing apparatus of the second, fourth, and sixth aspects, the wire rod can receive an equal force in the vicinity of the first roller and in the vicinity of the third roller, and the wire rod has a longitudinal direction. It can exhibit a uniform plastic deformation as a whole.

[Brief description of drawings]

FIG. 1 is a schematic view showing a piston ring manufacturing apparatus according to a first embodiment of the present invention, FIG.
(B) is a side view.

FIG. 2 is a schematic view showing a conventional piston ring manufacturing apparatus.

[Explanation of symbols]

1 Piston ring manufacturing equipment 2 wire rod 2A upper surface 2B One side 2C Other side 11 Feed roller 20 Curling roller group 21 first roller 21B axis 22 Second roller 22B axis 23 Third Roller 23B axis 30 cutting part 31 Lower clamp 32 Upper clamp 33 whetstone 40 Fourth roller

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yukichi Hayashi             5-2-6 Honmachi Nishi, Saitama City, Saitama Prefecture             Nippon Piston Ring Co., Ltd. inside the Yono factory (72) Inventor Mitsuo Fujita             No. 48 No. 48, Sakamotomachi, Izumi City, Osaka Prefecture             Noki Seisakusho F term (reference) 3J044 AA18 BA01 CB40 DA09 EA03                 4E070 AA03 AB10 BC11 BF06 BF08

Claims (6)

[Claims] 1. A feed roller for feeding a wire for a piston ring having an upper surface, a lower surface, one side surface and the other side surface in one direction, and a feed roller arranged movably downstream of the feed roller and capable of contacting the one side surface. A first roller, a second roller movably arranged on the downstream side of the first roller and contactable with the other side surface, and a second roller movably arranged on the downstream side of the second roller and contacting the one side surface. A curling roller group for plastically deforming the wire rod to a constant curvature, and a curling roller for forming the wire rod deformed to the constant curvature into a distorted circular ring. A fourth roller arranged on the downstream side of the group so as to be movable so as to be able to come into contact with the other side surface, and for cutting the wire rod formed in the strained circular ring in a substantially radial direction of the strained circular ring, A cutting means arranged downstream of the fourth roller. In the stone ring manufacturing apparatus, the diameter of the second roller is set to be larger than the diameters of the first and third rollers, and the cutting means contacts the upper surface and the lower surface of the wire to fix the wire. An upper clamp and a lower clamp for clamping, and a grindstone movable in a direction connecting the upper surface and the lower surface in the upper clamp and the lower clamp for cutting the wire material clamped by the upper clamp and the lower clamp. And the upper clamp,
An apparatus for manufacturing a piston ring, wherein the lower clamp and the grindstone are integrally provided so as to be movable in the radial direction of the strained circular ring and adjustable in angle with respect to the one direction. 2. The distance between the rotation axis of the second roller and the rotation axis of the first roller and the distance between the rotation axis of the second roller and the rotation axis of the third roller are equal to each other. The piston ring manufacturing apparatus according to claim 1. 3. A feed roller for feeding a wire rod for a piston ring, which has an upper surface, a lower surface, one side surface and the other side surface, in one direction, and is arranged so as to be movable downstream of the feed roller and capable of contacting the one side surface. A first roller, a second roller movably arranged on the downstream side of the first roller and contactable with the other side surface, and a second roller movably arranged on the downstream side of the second roller and contacting the one side surface. A curling roller group for plastically deforming the wire rod to a constant curvature, and a curling roller for forming the wire rod deformed to the constant curvature into a distorted circular ring. A fourth roller arranged on the downstream side of the group so as to be movable so as to be able to come into contact with the other side surface, and for cutting the wire rod formed in the strained circular ring in a substantially radial direction of the strained circular ring, A cutting means arranged downstream of the fourth roller. In the stone ring manufacturing apparatus, the diameter of the second roller is set to be larger than the diameters of the first and third rollers, the cutting means is constituted by a laser cutting device, and the laser cutting device emits laser light. An apparatus for manufacturing a piston ring, wherein the direction is movable in the radial direction of the strained circular ring and the angle is adjustable with respect to the one direction. 4. The distance between the rotation axis of the second roller and the rotation axis of the first roller and the distance between the rotation axis of the second roller and the rotation axis of the third roller are equal to each other. The piston ring manufacturing apparatus according to claim 3. 5. A feed roller for feeding a wire for a piston ring, which has an upper surface, a lower surface, one side surface, and the other side surface, in one direction, and is arranged movably on the downstream side of the feed roller and is capable of contacting the one side surface. A first roller, a second roller movably arranged on the downstream side of the first roller and contactable with the other side surface, and a second roller movably arranged on the downstream side of the second roller and contacting the one side surface. A curling roller group for plastically deforming the wire rod to a constant curvature, and a curling roller for forming the wire rod deformed to the constant curvature into a distorted circular ring. A fourth roller arranged on the downstream side of the group so as to be movable so as to be able to come into contact with the other side surface, and for cutting the wire rod formed in the strained circular ring in a substantially radial direction of the strained circular ring, A cutting means arranged downstream of the fourth roller. In the stone ring manufacturing apparatus, the diameter of the second roller is set to be larger than the diameters of the first and third rollers, the cutting means is composed of a water jet cutter, and the water jet cutter is An apparatus for manufacturing a piston ring, wherein a jet injection direction is provided so as to be movable in a radial direction of the strained circular ring and an angle thereof can be adjusted with respect to the one direction. 6. The distance between the rotation axis of the second roller and the rotation axis of the first roller and the distance between the rotation axis of the second roller and the rotation axis of the third roller are equal to each other. The piston ring manufacturing apparatus according to claim 5.