Piston ring circumference surface polishing system

Abstract

This invention provides a piston ring circumferential surface grinding system for grinding the circumferential surface of piston ring blanks. During grinding, a first contact member, a second contact member, and a third contact member contact the circumferential surface of the piston ring blank and are arranged sequentially along the circumference of the piston ring blank. The second contact member is located on the inner side of the piston ring blank, while the first and third contact members are located on the outer side of the piston ring blank. One of the three components serves as a drive component to rotate the piston ring blank, and the other is a grinding component for grinding the circumferential surface of the piston ring blank. There is a speed difference between the linear velocity at the contact point between the grinding component and the piston ring blank and the linear velocity at the contact point between the drive component and the piston ring blank. This piston ring circumferential surface grinding system enables deburring of piston ring blanks with non-circular cross-sections, and is also compatible with grinding piston ring blanks with circular cross-sections.

Description

Technical Field

[0001] This invention relates to the field of piston ring grinding or deburring technology, specifically to a piston ring circumferential surface grinding system. Background Technology

[0002] Piston rings are a key component of internal combustion engines, serving functions such as sealing, oil control, heat transfer, and support. Due to the presence of openings, piston rings experience inconsistent contact pressure distribution circumferentially during assembly. To improve piston ring performance and achieve a contact pressure distribution more suited to engine performance requirements after installation, the shape of the piston ring in its free state can be fine-tuned. This means that the free state shape of the piston ring is not a traditional perfect circle. The utility model patent application CN205464202U, entitled "A Cylindrical Piston Ring Blank," discloses the aforementioned non-circular piston ring.

[0003] Non-circular piston rings can be produced as blanks through casting processes. Materials used in casting include ductile iron and alloy cast iron. The inner and outer circles of the cast piston ring blank are non-circular. Due to the required draft angle, the cross-sectional shape of the elliptical piston ring blank is trapezoidal. The piston ring blank casting process includes sand casting with one mold for four, six, eight, or ten rings. After sand removal and ring casting, the outer surface of a single elliptical piston ring blank has casting residues such as sprue remnants, casting flash, and casting burrs. These residues are hard; if not removed or not removed completely, subsequent machining processes become significantly more difficult, and tool life is drastically reduced.

[0004] General-purpose internal and external cylindrical grinding machines are unable to adapt to the surface shape of non-circular piston rings and complete the grinding of surface burrs and other defects. Some piston ring manufacturers also use simple mechanical devices for manual grinding of residual sprues, flash, and burrs on the inner and outer surfaces of elliptical piston ring blanks. This method is inefficient, and the working environment for operators is harsh, making it unsuitable for large-scale industrial production. A similar grinding fixture has been disclosed in invention patent CN115488727B entitled "A Grinding Device for PTFE Piston Rings," but the disclosed technical solution does not actually provide an effective technical solution for grinding non-circular piston rings. Summary of the Invention

[0005] To address the problem that existing grinding equipment cannot meet the needs of grinding and deburring the circumferential surface of non-circular piston rings, this invention provides a piston ring circumferential surface grinding system.

[0006] The present invention provides a piston ring circumferential surface grinding system for grinding the circumferential surface of a piston ring blank, comprising a first contact member, a second contact member, and a third contact member; during grinding, the first contact member, the second contact member, and the third contact member contact the circumferential surface of the piston ring blank and are arranged sequentially along the circumferential direction of the piston ring blank, wherein the second contact member is disposed on the inner side of the piston ring blank, and the first contact member and the third contact member are disposed on the outer side of the piston ring blank;

[0007] Of the first contact member, the second contact member, and the third contact member, one is a driving member for driving the piston ring blank to rotate, and the other is a grinding member for grinding the circumferential surface of the piston ring blank. There is a speed difference between the linear velocity of the grinding member at the contact point with the piston ring blank and the linear velocity of the driving member at the contact point with the piston ring blank.

[0008] Preferably, at least one of the first contact, the second contact, and the third contact is elastically pressed against the circumferential surface of the piston ring blank during the grinding operation.

[0009] Preferably, at least one of the first contact, the second contact, and the third contact can elastically float within a specific floating plane, which is perpendicular to the plane containing the central axes of the other two and passes through its own centerline.

[0010] Preferably, the support is disposed on a rotating base, and the grinding component and the driving component are disposed on a second frame attached to the rotating base. The rotating base rotates around a rotating axis to move the grinding component and the driving component away from or closer to the support. When the grinding component and the driving component are close to the support, they can press the piston ring blank onto the support.

[0011] Preferably, an elastic component is rotatably connected or hinged to the second frame, with the other end of the elastic component fixed; when the grinding member and the driving member press against the piston ring blank, the elastic component provides the required elastic clamping force.

[0012] Preferably, the grinding component and the driving component float elastically within a specific floating plane, which is perpendicular to the plane containing the rotation axes of the grinding component and the driving component, and passes through the center of the support component. The elastic floating arrangement of the grinding component and the driving component allows the rotation axis directions of the grinding component and the driving component to be finely adjusted to accommodate the differences in piston ring blanks grouped on the support component.

[0013] Preferably, a plurality of the support members are circumferentially distributed on the rotating base; the rotating base is rotatably configured to rotate the support members, on which the piston ring blanks are fitted, to the grinding station.

[0014] Preferably, one end of the support member is disposed on the rotating base, and the other end extends freely in a cantilever shape; the free-extending end of the support member is provided with a flange to prevent the piston ring blank from axially dislodging when it rotates.

[0015] Preferably, the support member is free to rotate; the flange is provided with a gap around the support member or is provided as a whole in a ring.

[0016] Preferably, at least one of the first contact and the third contact is a polishing element, and / or the second contact is a polishing element.

[0017] The piston ring circumferential surface grinding system of the present invention achieves deburring of the circumferential surface of piston ring blanks with non-circular cross-sections by sequentially arranging grinding components, driving components, and supporting components on the inner and outer circumferences of the piston ring blank. Since the grinding of the piston ring blank around its axis is not achieved by rotation, but by dynamic rotational grinding of the piston ring blank using a local three-point support method, it can adapt to changes in the circumferential curvature of the piston ring blank, enabling uniform grinding of the circumferential surface and batch grinding of piston ring blanks. It should be noted that this piston ring circumferential surface grinding system is also compatible with grinding piston ring blanks with circular cross-sections. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the piston ring circumferential surface grinding system of the present invention;

[0019] Figure 2 This is an improved embodiment of the piston ring circumferential surface grinding system of the present invention;

[0020] Figure 3 This is a schematic diagram illustrating a specific embodiment of the piston ring circumferential surface grinding system of the present invention;

[0021] Figure 4 for Figure 3 A schematic diagram of the specific structure of the rotating base 15 in the piston ring circumferential surface grinding system;

[0022] Figure 5 A schematic diagram of a further embodiment of a piston ring circumferential surface grinding system.

[0023] In the picture,

[0024] W: Piston ring blank O: Rotating shaft A1: First contact A2: Second contact A3: Third contact 11: Grinding part 12: Driving part 13: Support part 14: Elastic component 15: Rotating base 16: Telescopic component 151: Locking device 131: Flange 17: Second elastic component 18: Second frame Detailed Implementation

[0025] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. In this specification, the dimensions of the drawings do not represent the actual dimensions. They are only used to illustrate the relative positional and connection relationships between the components. Components with the same name or the same reference numeral represent similar or identical structures and are limited to illustrative purposes.

[0026] Figure 1 This is a schematic diagram of the piston ring circumferential surface grinding system of the present invention. The piston ring blank W and the surface of this piston ring circumferential surface grinding system are collectively referred to as the circumferential surface. Since the piston ring blank W has a non-circular cross-section in some designs, in order to achieve grinding of the piston ring blank W to adapt to its free shape, a second contact member A2 capable of contacting the inner circular surface can be provided on the inner side of the piston ring blank W, and a first contact member A1 and a third contact member A3 capable of contacting the outer circular surface can be provided on the outer side of the piston ring blank W. The first contact member A1, the second contact member A2, and the third contact member A3 are arranged sequentially along the circumferential direction of the piston ring blank W, which means that in the circumferential direction, the second contact member A2 is always located between the first contact member A1 and the third contact member A3, which is necessary. At least one of the first contact member A1, the second contact member A2, and the third contact member A3 is a grinding member 11 that contacts the surface of the piston ring blank W, wherein at least one other driving member 12 drives the piston ring blank W to rotate, and the remaining one optionally becomes a support member 13. During the grinding process, the piston ring blank W is driven to rotate by the drive component 12. The grinding operation on the circumferential surface of the piston ring blank W is achieved by the relative speed difference between the grinding component 11 and the contact point of the piston ring blank W. The deviation between the free shape and the perfect circle shape of the piston ring is small. This small difference can be absorbed by the equipment itself and the deformation of the piston ring blank W. Therefore, when the first contact component A1, the second contact component A2, and the third contact component A3 contact the piston ring blank W with a certain clamping force and support the piston ring blank W in a three-point manner at a certain section of the piston ring blank W, even if the curvature of the contact section changes slightly when the piston ring blank W rotates, it can still maintain stable contact with the three components, ensuring the stability of the grinding interface and allowing the surface of the piston ring blank W to be ground evenly. It is conceivable that when the second contact A2 is used as the grinding element 11, the piston ring circumferential surface grinding system can grind the piston ring blank W. Similarly, when the first contact A1 or the third contact A3 is used as the grinding element 11, the system can grind the piston ring blank W. Furthermore, it is not impossible that while the second contact A2 is used as the grinding element 11, one of the first contact A1 or the third contact A3 can also be used as the grinding element 11 to achieve simultaneous grinding of both circumferential surfaces of the piston ring blank W.

[0027] Figure 2 for Figure 1Several further improvements are implemented. Several operational forms are shown where at least one of the first contact A1, second contact A2, and third contact A3 is elastically floating. The elastic component 14 is merely illustrative; in actual structures, a more specific structure usually replaces it. In actual structures, the elastic component 14 is typically a gas spring, leaf spring, or other elastic structure where spring assemblies connect the corresponding contact to the frame. In fact, driving components such as cylinders and hydraulic cylinders, while used for position driving, can also play a similar role to the elastic component 14 when stationary, depending on their own characteristics. That is, the closed fluid pressure inside the hydraulic or pneumatic cylinder can provide certain damping and stiffness characteristics when the position is held, allowing any contact connected to the moving end of the hydraulic cylinder to elastically float within a small displacement range when the position is held. Based on the three-point support structure, the elastic component 14 can be set on the second contact A2 inside the piston ring blank W or on either the first contact A1 or the third contact A3 outside the piston ring blank W. Of course, it is also possible to set it simultaneously on both the outside and inside of the piston ring blank W. Finally, considering the installation of the elastic component 14 on the outside of the piston ring blank W, the elastic component 14 can be independently installed on the first contact A1 or the third contact A3, or more specifically, it can be installed on the rigid frame on which the first contact A1 and the third contact A3 are mounted. This elastically floating installation method allows at least one of the first contact A1, the second contact A2, and the third contact A3 to elastically press against the circumferential surface of the piston ring blank W during the grinding operation. At this time, the three-point support mechanism formed by the first contact A1, the second contact A2, and the third contact A3 can support the piston ring blank W between the three components. On the other hand, under appropriate elastic pressure, the support mechanism formed by the first contact A1, the second contact A2, and the third contact A3 can float against the surface of the piston ring blank W as the curvature of the piston ring blank W changes with the curvature of its contact section, thereby better responding to changes in the curvature of the piston ring blank W and achieving uniform grinding of the circumferential surface of the piston ring blank W.

[0028] Figure 3This is one specific embodiment of the present invention. The piston ring circumferential surface grinding system includes a support member 13. In this embodiment, in order to simultaneously feed the piston ring or piston ring assembly during the grinding operation, the support member 13 is disposed on the rotating base 15, and at least two sets of support members 13 can be arranged circumferentially along the edge of the rotating base 15. When one set of support members 13 is in the grinding position, the remaining set can be in the feeding position, so that the feeding preparation work in the subsequent grinding cycle can be completed simultaneously with the grinding. When the support member 13 is held in the grinding position, in order to prevent the positional change of the rotating base 15 from affecting the grinding operation, a locking device 151 can be provided on the rotating base 15 to mechanically lock the position of the rotating base 15 after the support member 13 enters the grinding position, so as to prevent the rotating base 15 from circumferentially moving and causing the position of the support member 13 to vibrate.

[0029] The grinding component 11 and the driving component 12 are mounted on a second frame attached to the rotating base 15. The second frame is rotatably mounted around the pivot O. The grinding component 11 and the driving component 12 are sequentially mounted on the second frame near the support member 13 at an appropriate distance. The side of the second frame away from the support member 13 is rotatably connected to or hinged to an elastic component 14. The pivot O is located between the side with the hinged elastic component 14 and the side with the grinding component 11 and the driving component 12. Therefore, when the elastic component 14 retracts, the grinding component 11 and the driving component 12 press against the support member 13, entering the grinding working state. Conversely, when the elastic component 14 extends, the grinding mechanism is opened, and the piston ring blank W can be removed from the grinding position by the rotation of the rotating base 15 or taken out by other material handling mechanisms. Other arrangements of the pivot O, elastic component 14, grinding component 11, and driving component 12 are also acceptable as long as the movement of the elastic component 14 can drive the grinding component 11 and the driving component 12 to move relative to the support member 13. The elastic component 14 can be a cylinder, hydraulic cylinder, or other actuating component. During grinding, the telescopic component 16 simultaneously performs the elastic clamping function achieved by the aforementioned elastic component 14. Furthermore, for piston ring blanks with different properties, the parameters of the telescopic component 16 can be adjusted to ensure that the second frame has appropriate rigidity, thereby ensuring that the grinding part 11 and the piston ring blank W are in close contact during grinding, guaranteeing uniform grinding. Adjusting the rigidity of the telescopic component 16 as referred to in this invention can at least refer to adjusting the fluid pressure of the telescopic component 16.

[0030] Figure 4This is a schematic diagram of the rotating base 15. The rotating base 15 is rotatably mounted on a corresponding machine base and is driven by a prime mover for controlled rotation. Since several support members 13 are circumferentially distributed on the rotating base 15, the position of the support members 13 can be precisely controlled when the rotating base 15 rotates. The edge of the rotating base 15 generally has a corresponding groove to match each support member 13. A locking device 151 is also provided on the base. When the support member 13 is located in a preset position in the grinding station, the locking device 151 can be placed in the corresponding groove of the rotating base 15, thus achieving mechanical locking of the locking device 151 and reliable and stable positioning of the support member 13. The support member 13 is as follows... Figure 4 Partial sectional view and enlarged view. One end is set on the rotating base 15, and the other end extends freely, forming a cantilever. Multiple piston ring blanks can be wound side by side around the support 13. During grinding, the piston ring blanks will rotate on the support 13 and may therefore be displaced along the axis, which may cause the piston ring blanks to fall off the free end of the support 13, affecting not only the completion of the grinding operation but also potentially causing safety risks. To address this, a flange 131 can be provided at the free end of the support 13. When the piston ring blank W rotates on the support 13, the contact point between the piston ring blank W and the support 13 is generally relatively close to the flange 131 in the projected section. Therefore, the flange 131 can stop the piston ring blank W from sliding along the axis, and the piston ring blank W will not slide off the support 13 during grinding. Generally, the support member 13 does not necessarily need to be freely rotatable. However, when the support member 13 is fixed, the sliding friction between the piston ring blank W and the support member 13 during rotation can cause severe local wear on the support member 13. Therefore, the support member 13 is preferably allowed to rotate freely around its own axis. When the support member 13 is freely rotatable, the flange 131 can be designed to be spaced around the support member 13 or to be an integral ring.

[0031] like Figure 5As shown, the grinding component 11 and the driving component 12 are preferably floated as a whole. The axial direction of the grinding component 11 and the driving component 12 can vary within a certain range based on this floating configuration to adapt to the piston ring blanks W. Specifically, the grinding component 11 and the driving component 12 can have a floating component within a specific floating plane. This floating plane is perpendicular to the plane of their rotation axis on one hand, and passes through the center of the support component 13 on the other. The floating configuration of the grinding component 11 and the driving component 12 can be achieved by second elastic components 17 located at both ends of the rotation axis of the grinding component 11, the driving component 12, or both as a whole, mounted on the second frame. Their function is to allow the grinding component 11 and the driving component 12 to better adapt to the grouped piston ring blanks W, thereby ensuring that each piston ring blank W can be ground uniformly. Generally, the second elastic component 17 can be a component with high stiffness and the same function as a spring. Especially for piston ring blanks W, the burrs and other imperfections on each piston ring blank W are often uneven; the second elastic component 17 can effectively address the surface unevenness problem in the initial stage of grinding. In some cases, the pivot on which the second frame rotates can be made floating to achieve the floating configuration of the grinding component 11 and the drive component 12.

[0032] A specific example is provided here to illustrate the grinding process in the above embodiments. The grinding component 11 rotates at 311 r / min, the drive component 12 rotates at 2900 r / min, and the support component 13 rotates freely. The grinding component 11 is a rubber roller with a certain degree of elasticity to ensure stable driving of any piston ring blank W. Under the aforementioned speed difference, the outer circle of the piston ring blank W can be stably ground by the drive component 12. On the other hand, the rotating base 15 switches the support component 13 between the loading preparation station and the grinding station at a speed of 16 r / min.

[0033] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A piston ring circumferential surface grinding system for grinding the circumferential surface of a non-circular cross-section piston ring blank (W), characterized in that, It includes a first contact (A1), a second contact (A2), and a third contact (A3); during the grinding operation, the first contact (A1), the second contact (A2), and the third contact (A3) contact the circumferential surface of the piston ring blank (W) and are arranged sequentially along the circumferential direction of the piston ring blank (W), with the second contact (A2) located on the inner side of the piston ring blank (W), and the first contact (A1) and the third contact (A3) located on the outer side of the piston ring blank (W); The first contact (A1), the second contact (A2), and the third contact (A3) are, respectively, a driving member (12) for driving the piston ring blank (W) to rotate, a grinding member (11) for grinding the circumferential surface of the piston ring blank (W), and a support member (13). There is a speed difference between the linear velocity of the grinding member (11) at the contact point with the piston ring blank (W) and the linear velocity of the driving member (12) at the contact point with the piston ring blank (W). At least one of the first contact (A1), the second contact (A2), and the third contact (A3) is elastically pressed against the circumferential surface of the piston ring blank (W) during the grinding operation; The grinding component (11) and the driving component (12) float elastically within a specific floating plane. This floating plane is perpendicular to the plane containing the rotation axis of the grinding component (11) and the driving component (12) on one hand, and passes through the center of the support component (13) on the other hand. The elastic floating arrangement of the grinding component (11) and the driving component (12) allows the rotation axis direction of the grinding component (11) and the driving component (12) to be finely adjusted to accommodate the differences in the piston ring blanks (W) grouped on the support component (13).

2. The piston ring circumferential surface grinding system according to claim 1, characterized in that, The support member (13) is disposed on the rotating base (15), and the grinding member (11) and the driving member (12) are disposed on the second frame (18) attached to the rotating base (15). The rotating base (15) rotates around the rotating shaft (O) to move the grinding member (11) and the driving member (12) away from or close to the support member (13). When the grinding member (11) and the driving member (12) are close to the support member (13), they can press the piston ring blank (W) onto the support member (13).

3. The piston ring circumferential surface grinding system according to claim 2, characterized in that, An elastic component (14) is rotatably connected to the second frame (18), with the other end of the elastic component (14) fixed; when the grinding component (11) and the driving component (12) press the piston ring blank (W), the elastic component (14) provides the required elastic clamping force.

4. The piston ring circumferential surface grinding system according to claim 2, characterized in that, Several of the support members (13) are circumferentially distributed on the rotating base (15); the rotating base (15) is rotatably configured to rotate the support members (13) with the piston ring blank (W) fitted on them to the grinding station.

5. The piston ring circumferential surface grinding system according to claim 2, characterized in that, One end of the support member (13) is mounted on the rotating base (15), and the other end extends freely in a cantilever shape; the free-extending end of the support member (13) is provided with a flange (131) to prevent the piston ring blank (W) from axially dislodging when it rotates.

6. The piston ring circumferential surface grinding system according to claim 5, characterized in that, The support member (13) can rotate freely; the flange (131) is arranged with a gap around the support member (13) or is arranged in a ring as a whole.

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