JP2002046051A - Polishing apparatus for outer periphery of piston ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing apparatus for the outer periphery of a piston ring having low polishing resistance and high productivity. SOLUTION: This sliding polishing apparatus 1 for a piston ring includes a ring base 10, a pusher 20, a ring retainer 30 and a lap 40. The piston ring 2 is placed on the upper surface of the ring base 10 and pushed radially inwardly of the piston ring by the pusher 20 from three directions so as to be deformed into a true circle. The piston ring 2, clamped by the ring retainer 30 and the ring base 10 and deformed into a true circle, rotates about the axis of the piston ring 2 integrally with the ring base 10. Then the outer peripheral surface of the piston 2 is polished as it abuts a lapping film 42 mounted around a roller 41 provided on the lap 40, the lapping film vibrating in the direction of the axis of the piston ring 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outer peripheral polishing device for a piston ring, and more particularly to an outer peripheral polishing device for polishing an outer peripheral surface of a piston ring into a barrel shape.

[0002]

2. Description of the Related Art Conventionally, as an outer peripheral polishing device for performing a final processing of an outer peripheral surface of a piston ring, a type in which an outer peripheral surface of a piston ring is polished using a grindstone or a type in which a lapping sleeve is used to polish the outer peripheral surface. It has been known.

Japanese Patent Application Laid-Open No. 53-24183 discloses an outer peripheral polishing apparatus for processing an outer peripheral surface of a piston ring held by a mandrel into a barrel shape using a plurality of cutting tools constituted by a grindstone. I have. As shown in FIG. 3, the plurality of piston rings 102 are coaxially attached to the mandrel 160 at regular intervals in a state where the abutment is closed and the detent collar 150 is interposed between the piston rings 102. . The mandrel 160 and the piston ring 102 are configured to be integrally rotatable about the axis of the mandrel 160.

[0004] A plurality of cutting tools 142 constituted by a grindstone
Are fixed to the tool rest 140 at the same fixed interval as the interval at which the plurality of piston rings 102 are attached to the mandrel 160. The tip of each cutting tool 142 is arranged between the piston rings 102 when the outer peripheral polishing device is stopped.

[0005] The tool rest 140 swings in the left-right direction in FIG. 3, and moves toward and away from the piston ring 102 while swinging in the left-right direction. That is, in FIG. 3, when the tool rest 140 is located at the far left or right, the tool rest 140 is closest to the mandrel 160, and when the tool rest 140 is located at the center in FIG. Is located farthest from the mandrel 160. Byte 1
Since 42 swings integrally with the tool rest 140, the tip of the cutting tool 142 for cutting the outer periphery of the piston ring 102 also
As the tool post 140 swings, the tool rest 140 moves and separates from the piston ring 102 while swinging. Therefore, the outer circumference of the piston ring 102 can be processed into a barrel shape.

[0006] Japanese Patent Publication No. 2-2653 discloses an outer periphery polishing apparatus for cutting the outer periphery of a piston ring using a buff made of a nonwoven fabric impregnated with aluminum oxide. As shown in FIG. 4, the plurality of piston rings 202 are coaxially fixed at regular intervals with their abutments closed and washers 250 interposed between the piston rings 202. Piston ring 2
02 is in contact with the outer peripheral surface of a substantially disk-shaped buff 260, and the buff 26
By rotating 0, a cutting process can be performed on the outer peripheral surface of the piston ring 202.

[0007] Japanese Patent Application Laid-Open No. 3-104560 describes an outer peripheral polishing apparatus for lapping a piston ring using a lapping sleeve, lapping oil and abrasive grains. As shown in FIG. 5, the piston ring 302 is set and held on the backup ring 350. The backup ring 350 is configured to rotate integrally with the rotation shaft 361 by the key 360. Piston ring 302 set on backup ring 350
Is at a predetermined angle with respect to the axial direction of the rotating shaft 361, and is configured to perform the Kellen drive with the rotation of the rotating shaft 361.

[0008] The backup ring 350 on which the piston ring 302 is set is inserted into a wrapping sleeve 370 rotating in the opposite direction to the rotation shaft 361 while being integrally rotated with the rotation shaft 361. Lapping oil and abrasive particles of large particle size are inserted into the lapping sleeve 370, and lapping is performed in a state where the piston ring slides on the cylinder liner in an actual engine. .

[0009]

However, Japanese Patent Application Laid-Open No. Hei 3-1
In the case of a type using abrasive powder such as abrasive grains as described in Japanese Patent No. 04560, high precision is required for managing the diameter of the sleeve for polishing the piston ring and the abrasive powder, and the production cost is high. Was. Further, it has been impossible to grind the outer corner of the piston ring.

JP-A-53-24183 and Japanese Patent Publication No.
In the type in which the outer peripheral surface of the piston ring is polished using a grindstone or a nonwoven fabric as described in -2653, the roundness of the piston ring when setting the piston ring, the time when cutting the piston ring, It is necessary to precisely control cutting resistance, etc.
High precision is required for jigs and grindstones used for cutting and polishing, and high precision is required for controlling the number of rotations of a piston ring and a grindstone that rotates during cutting and polishing, which also increases the production cost.

[0011] Further, in the above-mentioned conventional peripheral grinding apparatus for a piston ring, the polishing resistance in polishing is high. Therefore, when the peripheral ring polishing apparatus is used to process a piston ring having been subjected to a surface treatment. In addition, defects such as peeling and chipping were likely to occur.

Accordingly, an object of the present invention is to provide a piston ring outer peripheral polishing apparatus having low polishing resistance and high productivity.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method for forming a piston ring in a free state into a perfect circle by radially moving a plurality of portions of an outer peripheral surface of the piston ring radially inward. A ring perfect circle holding means that presses the piston ring, and a piston ring that is located inside the ring perfect circle holding means and is held in a perfect circle shape is pinched and fixed from both axial end surfaces of the piston ring; A ring fixing / rotating means that is driven to rotate about the axis of the piston ring, and is provided outside the ring fixing / rotating means so as to be movable in a radial direction of the piston ring, and is provided by the ring fixing / rotating means. A polishing stand for pressing and polishing the outer peripheral surface of the rotating ring, wherein the polishing stand uses a band-shaped wrapping film as an abrasive, and It is moved in the circumferential direction of the outer peripheral surface of the ring, and the lapping film to provide an outer circumference polishing apparatus of a piston ring with a driving means for vibrating in the axial direction of the piston ring.

Here, the driving means includes a roller capable of pressing the outer peripheral surface of the piston ring and running the wrapping film, and the roller presses the outer periphery of the ring with the wrapping film interposed. It is preferable that the corner portion following the outer peripheral surface of the piston ring can be polished in an arc shape by vibration of the roller in the axial direction of the piston ring.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An outer peripheral polishing apparatus for a piston ring according to an embodiment of the present invention will be described with reference to FIGS. The outer peripheral polishing device 1 for the piston ring is provided with a ring base 10 for horizontally supporting the piston ring 2. The upper surface 10A (FIG. 2), which is the uppermost portion in the vertical direction, has a horizontal circular shape, and is connected to a motor (not shown). When driven by a motor (not shown), the ring base 10 is configured to be rotatable about the axis of the circular upper surface 10A. Piston ring 2
Is transported by a lifter (not shown) provided in the outer peripheral polishing apparatus 1 and is arranged on the outer peripheral portion of the upper surface 10A of the ring base 10 so as to be coaxial with the upper surface 10A of the ring base 10. ing.

When the piston ring 2 is placed on the upper surface 10A of the ring base 10, the abutment of the piston ring 2 is in an open state. Three pushers 20, 20, 20 for deforming the piston ring 2 into a perfect circle are provided. Each pusher 20 is arranged at a radially outer position of the piston ring 2 placed on the ring base 10 at equal intervals in the circumferential direction of the piston ring 2. Two rollers 2
1, 21 are rotatably provided. The rotation axis of each roller 21 is parallel to the axis of the ring base 10.
The roller 21 is configured to move horizontally together with the pusher 20 and press the piston ring 2 inward in the radial direction of the piston ring 2 so that the abutment of the piston ring 2 is closed. Pusher 2
0 corresponds to the ring perfect circle holding means.

The outer peripheral polishing apparatus 1 is provided with a ring retainer 30 for maintaining a state in which the abutment of the piston ring 2 is closed by the pusher 20. The ring presser 30 has a vertical circular lower surface 30A (FIG. 2), and is configured to be coaxially movable with respect to the piston ring placed on the ring base 10. The lower surface 30A of the ring presser 30 presses the closed piston ring 2 in the axial direction of the piston ring 2 and in a direction approaching the ring base 10, and clamps the piston ring 2 with the ring base 10. By doing so, the state of the perfect circle where the abutment of the piston ring 2 is not opened is maintained. The ring presser 30 is configured to be rotatable integrally with the ring base 11 while the piston ring 2 is sandwiched between the ring base 10 and the ring holder 10. The ring base 10 and the ring holder 30 correspond to ring fixing / rotating means.

The outer peripheral polishing apparatus 1 is provided with a wrap 40 for polishing the outer peripheral surface 2A of the piston ring 2 which is placed on the ring table 10 and has a closed mouth. The wrap 40 includes the piston ring 2 placed on the ring base 10.
Are provided at a position radially outward of the piston ring 2 so as to be able to move horizontally.
And an angle of about 120 ° with respect to the axis.

One roller 41 is provided at the tip of each wrap 40. Roller 41 is wrap 40
Of the rollers 41 (FIG. 2).
Are all parallel to the axis of the ring base 10. The head unit 43 having the roller 41 is connected to a motor (not shown).
Is configured to be able to vibrate in the direction of the rotation axis. The width of the vibration is about 7 mm. A roller (not shown) connected to a motor (not shown) is provided inside each wrap 40, and a belt-shaped wrapping film 42 is mounted between the roller (not shown) and the roller 41. . When the piston ring 2 rotates integrally with the ring base 10, the lap 4
0 moves horizontally inward in the radial direction of the piston ring 2,
Wrapping film 42 is outer peripheral surface 2A of piston ring
After the contact, the roller 41 vibrates in the axial direction so that the outer peripheral surface 2A of the piston ring 2 can be polished. In addition, the outer peripheral surface 2A
During the polishing, the roller (not shown) is rotated by the drive of a motor (not shown), and the wrapping film 42 is conveyed. 2A
Can be polished. The head unit 43 having the rollers 41 corresponds to a polishing stand.

The roller 41 is made of an elastically deformable material such as urethane or MC nylon, and has a hardness of about JIS HS 70 degrees. Since the roller 41 is made of an elastically deformable material, the roller 41
When the wrapping film 42 mounted on the outer peripheral surface is in contact with the outer peripheral surface 2A of the piston ring 2, the outer peripheral surface 2A
Presses the wrapping film 42 and the roller 41 to deform the roller 41 as shown in FIG.
Therefore, as the wrapping film 42 comes into contact with the upper end 2B and the lower end 2C of the outer peripheral surface 2A, the central portion 2D of the outer peripheral surface 2A is polished into a barrel having a predetermined curvature. Not only can the upper and lower ends 2B, 2C, that is, the corners following the outer peripheral surface of the piston ring be replaced with the central portion 2D of the barrel-shaped outer peripheral surface 2A.
Can be a curved surface having a curvature smaller than that of. An arbitrary curvature can be obtained by adjusting the pressing force of the roller 41 against the piston ring 2. It is most suitable for manufacturing a barrel-shaped piston ring described in Japanese Patent Application No. 2000-229310 by the same applicant as the present application.

Next, the operation of the outer peripheral polishing device 1 for a piston ring will be described. First, the piston ring 2 conveyed by a lifter (not shown) is placed on the upper surface 10A of the ring base 10. Next, three pushers 20
Is pressed uniformly from the outside to the inside in the radial direction of the outer peripheral surface 2 </ b> A of the piston ring 2 to close the abutment of the piston ring 2. As described above, since the three pushers are arranged at equal intervals in the circumferential direction of the piston ring 2, the piston ring 2 can be deformed into a perfect circle to close the abutment. While maintaining the state in which the piston ring 2 is deformed to a perfect circle, the ring presser 30 approaches the piston ring 2 coaxially with respect to the piston ring 2 from above in the vertical direction, abuts and presses, and the ring presser 30 and the ring presser. The piston ring 2 is sandwiched between the table 10 and the closed state of the abutment of the piston ring 2 is maintained.

Next, a motor (not shown) is driven to rotate the ring base 10 around the axis of the upper surface 10A of the circular ring base 10. Piston ring 2 and ring holder 30
Also rotates integrally with the ring base 10. On the other hand, the roller 41
The head portion 43 of the wrap 40 having the roller 41 is driven by a motor (not shown) so that
Vibrates in the axial direction. When a motor (not shown) inside the wrap is driven, a roller (not shown) inside the wrap rotates, and accordingly, the roller 41 rotates, and the wrapping film 42 is conveyed around. Wrapping film 4
2 is the same as the rotation direction of the piston ring 2.

The wrap 40 is connected to the piston ring 2
Moves inward from the outside in the radial direction, and the wrapping film 42 comes into contact with the outer peripheral surface 2 </ b> A of the piston ring 2. Further, the wrap 40 moves inward in the radial direction of the piston ring 2, and the roller 41 presses the wrapping film 42 against the piston ring 2. Since the roller 41 is elastically deformable, the wrapping film 42 and the piston ring 2 are engaged with the roller 41 as shown in FIG. In this state, the piston ring 2 rotates about its axis, the head portion 43 having the roller 41 vibrates together with the wrapping film 42, and the wrapping film 42 is also conveyed around and the outer peripheral surface 2A of the piston ring 2 is Polishing is performed.

After the polishing is performed for a desired time, the wrap 40 is retracted outward in the radial direction of the piston ring 2, and the wrapping film 42 is moved to the outer peripheral surface 2A of the piston ring 2.
After being separated from the conveyance of the wrapping film 42,
The rotation of the piston ring 2 and the vibration of the roller 41 stop. After the ring presser 30 separates from the piston ring 2, the pusher 20 retreats radially outward of the piston ring 2, the roller 21 separates from the outer peripheral surface 2 </ b> A of the piston ring 2, and the abutment of the piston ring 2 be opened. Then, the piston ring 2 is removed from the outer peripheral polishing device 1 by a lifter (not shown), and polishing of the outer peripheral surface 2A of the piston ring 2 is completed.

Since the lapping film 42 is used to polish the outer peripheral surface 2A of the piston ring 2 without using polishing powder or a grindstone, it is necessary to manage the accuracy of the polishing powder and the grindstone which has been conventionally required. And the production cost can be reduced. Also, the polishing resistance can be reduced,
The occurrence of defects such as peeling and chipping can be reduced, and the productivity can be increased.

When the piston ring 2 rotates around the axis of the piston ring 2, the head 43 having the roller 41 vibrates in the axial direction of the piston ring 2 together with the wrapping film 42. A cross hatch in the form of a stitch can be formed on the outer peripheral surface 2A. By adjusting the rotation speed of the ring base 10,
The gap between the stitches can be adjusted, and the roughness of the stitch-shaped crosshatch can be set to an arbitrary value by using the wrapping films 42 having different roughnesses.

The outer peripheral polishing device for a piston ring according to the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made within the scope described in the claims. For example, in the peripheral grinding device for the piston ring according to the present embodiment, the hardness of the roller 41 of the wrap 40 is determined according to JIS HS7.
The angle is set to about 0 degree, but may be in the range of 50 to 100 degrees. By using the rollers 41 having different hardnesses, the curvature of the central portion 2D and the upper and lower ends 2B and 2C of the outer peripheral surface 2A can be set to desired values.

The number of the pushers 20, the rollers 20, the wraps 40, and the rollers 41 is not limited to the number of the outer peripheral polishing device for the piston ring according to the above-described embodiment.

While the lapping film 42 is in contact with the outer peripheral surface 2A of the piston ring 2 and the outer peripheral surface 2A is being polished, the pusher 20 pushes the piston ring 2 inward in the radial direction of the piston ring 2. The piston ring 2 that has been continuously pressed but the abutment was closed and transformed into a perfect circle
At a point after the ring is held between the ring presser 30 and the ring base 10 and before the outer peripheral surface 2A is polished by the wrapping film 42, the pusher 20 is retracted radially outward of the piston ring 2, and the piston Ring 2
May be separated from it.

[0030]

According to the apparatus for polishing the outer periphery of a piston ring according to the first aspect, since a belt-shaped wrapping film is used as the polishing material, it is necessary to control the accuracy of the polishing powder or grindstone conventionally used as the polishing material. And the production cost can be reduced. Further, since the polishing resistance can be reduced, the occurrence of defects such as peeling and chipping can be reduced, and the productivity can be increased.

Further, since the wrapping film is vibrated in the axial direction of the piston ring while the piston ring is driven to rotate about the axis of the piston ring, the outer peripheral surface of the piston ring is polished. An iris-shaped cross hatch can be formed on the outer peripheral surface of the piston ring.

Further, since the ring perfect circle holding means for pressing a plurality of portions on the outer peripheral surface of the piston ring inward in the radial direction is provided, the outer shape of the piston ring in a free state can be easily deformed to a perfect circle.

According to the apparatus for polishing the outer periphery of a piston ring according to the second aspect, the outer peripheral surface of the piston ring can be pressed and a roller for running the wrapping film is provided. Since the roller is made of a material that can be elastically deformed when pressed, the roller vibrates in the axial direction of the piston ring to polish the outer peripheral surface of the piston ring. It can be polished in an arc shape.

[Brief description of the drawings]

FIG. 1 is a plan view showing an outer peripheral polishing device for a piston ring according to an embodiment of the present invention.

FIG. 2 is a side view of a main part showing an outer periphery polishing apparatus for the piston ring according to the embodiment of the present invention.

FIG. 3 is a sectional view of an essential part showing a conventional peripheral grinding device for a piston ring.

FIG. 4 is a side view of a main part showing a conventional peripheral grinding device for a piston ring.

FIG. 5 is a cross-sectional view of a main part showing a conventional peripheral grinding device for a piston ring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer periphery grinding device 2 Piston ring 2A Outer peripheral surface 2B Upper end 2C Lower end 2D Central part 10 Ring base 20 Pusher 21 Roller 30 Ring holder 40 Lapp 41 Roller 42 Wrapping sheet

Claims (2)

[Claims] 1. A ring perfect circle holding means for pressing a plurality of portions of an outer peripheral surface of a piston ring radially inward in order to deform an outer shape of a piston ring in a free state into a perfect circle, and the ring perfect circle holding means. Ring fixing / rotating means for pinching and fixing the piston ring, which is located inside of the piston ring and whose shape is held in a perfect circle, from both end surfaces in the axial direction of the piston ring, and rotationally drives around the axis of the piston ring. And located outside the ring fixing / rotating means and movably provided in the radial direction of the piston ring.
A polishing stand that presses and grinds the outer peripheral surface of the ring that is rotated by the rotating means, the polishing stand uses a band-shaped wrapping film as an abrasive, and the band-shaped wrapping film is formed in the circumferential direction of the outer peripheral surface of the piston ring. An outer peripheral polishing device for a piston ring, comprising a driving means for moving and oscillating the wrapping film in an axial direction of the piston ring. 2. The driving means comprises a roller capable of pressing the outer peripheral surface of the piston ring and running the wrapping film, wherein the roller presses the outer periphery of the ring with the wrapping film interposed. 2. A piston ring according to claim 1, wherein said piston ring is made of a material which can be elastically deformed, and a corner portion following an outer peripheral surface of said piston ring can be polished in an arc shape by vibration of said roller in an axial direction of said piston ring. Peripheral polishing device.