Oil scraper ring for a piston

Abstract

An oil scraper ring for a piston includes a top surface, a bottom surface, an inner surface, and an outer surface. The top surface has a first planar portion and a first inclined portion. The bottom surface has a second planar portion and a second inclined portion. The second inclined portion is configured to slidably contact the first inclined portion to adjust a diameter of the oil scraper ring. The inner surface connects the top surface to the bottom surface. The outer surface, opposite the inner surface, is configured to form 360 degree contact with a cylinder wall to substantially limit an amount of oil that enters a combustion chamber of the cylinder.

Description

Technical Field

[0001] The present invention generally relates to piston rings, for example to oil scraper rings for pistons. Background Technology

[0002] A power system (e.g., a four-stroke engine) drives a machine by converting the chemical energy stored in fuel (e.g., diesel, gasoline, and / or similar fuels) into mechanical work. Depending on the type of power system, an air-fuel mixture is formed in or introduced into the combustion chamber of the cylinder. The piston is mounted within the cylinder and slides cyclically between top dead center (TDC) and bottom dead center (BDC) positions along a lubricated surface. As the piston moves toward the TDC position, it compresses the air-fuel mixture in the combustion chamber, causing combustion. The resulting force pushes the piston downward toward the BDC position, and the cycle repeats. Because the piston is connected to the machine's power transmission system, the continuous movement of the piston propels and / or drives the machine.

[0003] To adequately seal the combustion chamber (e.g., to adequately limit the leakage of the air-fuel mixture from the combustion chamber and / or to adequately limit the entry of oil from lubricating surfaces into the combustion chamber), the piston includes expandable rings mounted to its outer surface. However, because the expandable rings have end gaps, they can allow oil droplets to flow directly into the combustion chamber. Therefore, the powertrain may experience performance problems such as increased fuel consumption, increased surface deposits, increased emissions, and / or accidental combustion during charging.

[0004] U.S. Patent Application Publication No. 2012 / 0112415, published on May 10, 2012, discloses a rotary sealing ring (or piston ring). The sealing ring is separated to define a first free end (or arm) and a second free end (or arm) that can contact and overlap each other, and they are movable relative to each other in the circumferential direction along a separation surface located at the interface between the mating cut surfaces of the first and second free ends.

[0005] The oil scraper ring of the present invention solves one or more of the problems described above, and / or other problems in the art. Summary of the Invention

[0006] In some embodiments, a scraper ring for a piston includes an arcuate body, a first protrusion, and a second protrusion; the arcuate body includes an inner surface, an outer surface, a first end face connecting the inner surface to the outer surface, and a second end face opposite to the first end face; the first protrusion extends circumferentially from the first end face, wherein the first protrusion includes a first inner surface, a first outer surface, and a first contact surface connecting the first inner surface to the first outer surface; the second protrusion extends circumferentially from the second end face, wherein the second protrusion includes a second inner surface, a second outer surface, and a first contact surface connecting the second inner surface to the second outer surface. A second contact surface; wherein the first contact surface is configured to slidably contact the second contact surface to adjust the diameter of the scraper ring; wherein, when the first contact surface contacts the second contact surface, the inner surface, the first inner surface, and the second inner surface together define an inner surface of the scraper ring extending 360 degrees relative to the central axis of the scraper ring, and the outer surface, the first outer surface, and the second outer surface together define an outer surface of the scraper ring extending 360 degrees relative to the central axis; wherein at least one of the first protrusion or the second end face includes a groove that allows fluid to flow from the inner surface of the scraper ring to the outer surface of the scraper ring.

[0007] In some embodiments, an oil scraper ring for a piston includes a top surface, a bottom surface, an inner surface, and an outer surface; the top surface has a first planar portion and a first inclined portion; the bottom surface has a second planar portion and a second inclined portion, wherein the second inclined portion is configured to slidably contact the first inclined portion to adjust the diameter of the oil scraper ring; the inner surface connects the top surface to the bottom surface; the outer surface is opposite to the top surface, wherein the outer surface is configured to form a 360-degree contact with the cylinder wall to sufficiently limit the amount of oil entering the combustion chamber of the cylinder.

[0008] In some embodiments, an oil scraper ring includes an outer surface and a bottom surface. The outer surface is configured to form a 360-degree contact with the cylinder wall to sufficiently restrict the flow of oil between the oil scraper ring and the wall into the combustion chamber of the cylinder. The bottom surface is configured to form a less than 360-degree contact with the piston ring land to allow gas to flow between the oil scraper ring and the piston ring land. Attached Figure Description

[0009] Figure 1 This is an internal view of an exemplary power system that includes multiple rings.

[0010] Figure 2 This is a cross-sectional view of the power system.

[0011] Figure 3 It is an isometric view of the first end of an oil scraper ring with multiple rings.

[0012] Figure 4 This is an isometric view of the second end of the oil scraper ring.

[0013] Figure 5This is the bottom isometric view when the first and second ends of the oil scraper ring are in an overlapping state.

[0014] Figure 6 This is a top isometric view of the oil scraper ring when the first and second ends are overlapping. Detailed Implementation

[0015] This invention relates to a ring suitable for any system comprising a movable connection between two fluid chambers. For example, the system could be a power system, and the movable connection could be a piston separating a cylinder combustion chamber from the crankcase interior. The combustion chamber may contain an air-fuel mixture, while the crankcase interior may contain oil. The power system can be implemented in a vehicle (e.g., a motor vehicle, rail vehicle, ship, aircraft), a generator, or similar machine.

[0016] To simplify the explanation below, the same reference numerals may be used to denote similar features. The accompanying drawings may not be to scale.

[0017] Figure 1-2 An exemplary power system 100 is shown. (As...) Figure 1 As shown, the power system 100 includes a cylinder 102, an intake valve 104, a fuel injector 106, an exhaust valve 108, a piston assembly 110, and a crankcase 112. The cylinder 102 includes an upper end 114, a lower end 116, and a wall 118 extending between the upper end 114 and the lower end 116. The upper end 114 of the cylinder 102 includes an intake port 120, a fuel inlet 122, and an exhaust port 124. The intake valve 104 is movably accommodated in the intake port 120 to allow air to pass through and enter the cylinder 102. The fuel injector 106 is mounted to the fuel inlet 122 to allow fuel to pass through and enter the cylinder 102, thereby mixing with air to form an air-fuel mixture. The exhaust valve 108 is movably accommodated in the exhaust port 124 to allow exhaust gases to pass through and exit the cylinder 102. The lower end 116 of the cylinder 102 is connected to the crankcase 112.

[0018] Piston assembly 110 includes piston 126, compression ring 128, oil scraper ring 130, oil control ring 132, and connecting rod 134. Piston 126, defining the lower end of combustion chamber 136, is slidably mounted within cylinder 102 and travels in a four-stroke cycle (including intake, compression, combustion, and exhaust strokes) to convert the chemical energy stored in the fuel into mechanical work. Figure 2As shown, to minimize friction between the piston 126 and the wall 118, the wall 118 may include an oil layer 202. The piston 126 includes a first annular groove 204, a second annular groove 206, and a third annular groove 208. A first piston ring land 210 separates the first annular groove 204 from the second annular groove 206, and a second piston ring land 212 separates the second annular groove 206 from the third annular groove 208. In other words, the first piston ring land 210 includes a first upper surface 214 and a first lower surface 216, the first upper surface 214 defining the bottom of the first annular groove 204 and the first lower surface 216 defining the top of the second annular groove 206. The second piston ring land 212 further includes a second upper surface 218 and a second lower surface 220, the second upper surface 218 defining the bottom of the second annular groove 206 and the second lower surface 220 defining the top of the third annular groove 208.

[0019] The compression ring 128 is structured and positioned within the first annular groove 204 to sufficiently restrict the air-fuel mixture from leaving the combustion chamber 136 between the piston 126 and the wall 118. The oil scraper ring 130 is structured and positioned within the second annular groove 206 to further seal the combustion chamber 136, sufficiently limiting the amount of oil entering the combustion chamber 136 from the oil layer 202. This will be discussed in conjunction with... Figure 3-6 The oil scraper ring 130 is described. The oil scraper ring 130 has an inner surface 222, an outer surface 224 opposite to the inner surface 222, an uppermost surface 226 connecting the inner surface 222 to the outer surface 224, and a lowermost surface 228 opposite to the uppermost surface 226. In use, the outer surface 224 of the oil scraper ring 130 contacts a wall 118, and the lowermost surface 228 of the oil scraper ring 130 contacts a second upper surface 218 of a second piston ring land 212. An oil control ring 132 is structured and positioned within a third annular groove 208 to further restrict oil entry into the combustion chamber 136. A connecting rod 134 is configured to connect the piston 126 to one or more components (e.g., crank pins, cranks, and / or crankshafts) within the crankcase 112 to drive the powertrain.

[0020] As mentioned above, providing Figure 1-2 As an example. Other examples can be used with reference to... Figure 1-2 The differences are as described. For example, the number and arrangement of the components (e.g., cylinder 102, intake valve 104, fuel injector 106, exhaust valve 108, crankcase 112, piston 126, compression ring 128, oil scraper ring 130, and / or oil control ring 132) may differ from those of the cylinder 102. Figure 1-2 The difference is shown. Therefore, compared to Figure 1-2Compared to the one shown, it may have additional components, fewer components, different components, components of different shapes, and / or components arranged differently. Furthermore, as mentioned above, it should be understood that although the power system 100 shown and described above is a diesel engine, the power system 100 may alternatively be a gasoline engine or another type of system. The power system 100 may include a plurality of cylinders 102 arranged in a series configuration, a "V" configuration, or another suitable configuration.

[0021] Figure 3-6 The oil scraper ring 130 is shown. In the following description, the first end 302 and the second end 402 of the oil scraper ring 130 will be described. However, it should be understood that the first end 302 and the second end 402 are connected by a single arc-shaped material piece (hereinafter referred to as the arc-shaped body 304).

[0022] like Figure 3-6 As shown, the scraper ring 130 is an open ring including an arcuate body 304, a first protrusion 306, and a second protrusion 404. The arcuate body 304 includes an inner surface 308, an outer surface 310, a top surface 312, a bottom surface 314, a first end face 316, and a second end face 406. The inner surface 308 includes a chamfer 318, which helps to seal the scraper ring 130 against the second upper surface 218 of the second piston ring land 212 (e.g., due to the downward force of fluid trapped between the compression ring 128 and the scraper ring 130). The outer surface 310 is generally cylindrical and is positioned opposite the inner surface 308 to contact the wall 118 of the cylinder 102. The top surface 312 defines the uppermost end surface 226 of the scraper ring 130, which is generally planar and connects the inner surface 308 to the outer surface 310. The bottom surface 314 defines the lowermost surface 228 of the oil scraper ring 130, which is also substantially planar and opposite the top surface 312. The bottom surface 314 is configured to contact the second upper surface 218 of the second piston ring land 212 to sufficiently restrict a certain amount of oil or other fluid from bypassing the oil scraper ring 130.

[0023] A first protrusion 306 extends circumferentially from a first end face 316 and has a generally prismatic shape. The first protrusion 306 includes a first inner surface 320, a first outer surface 322, a first contact surface 324, a first bottom surface 326, a first side surface 328, and a first groove 330. The first inner surface 320 of the first protrusion 306 abuts against and extends from the inner surface 308 of the arch-shaped body 304. The first outer surface 322 is opposite to the first inner surface 320, abuts against and extends from the outer surface 310 of the arch-shaped body 304. The first contact surface 324 connects the first inner surface 320 to the first outer surface 322 and extends relative to the first bottom surface 326 at a first angle. For example, the first angle may be in the range of approximately 5 degrees to approximately 65 degrees. As another example, the first angle may be in the range of approximately 10 degrees to approximately 30 degrees. The first bottom surface 326 is opposite to the first contact surface 324, abuts against and extends from the bottom surface 314 of the arch-shaped body 304. The first side surface 328 is generally parallel to the first end face 316. The first groove 330 has a curved cross-sectional shape and extends radially from the first inner surface 320 to the second outer surface 322 between the first side surface 328 and the first bottom surface 326.

[0024] A second protrusion 404 extends circumferentially from a second end face 406, the second end face 406 including a second groove 408 extending radially from the inner surface 308 along a bottom surface 314 to the outer surface 310 of the arch-shaped body 304. The second protrusion 404 includes a second inner surface 410, a second outer surface 412, a second top surface 414, a second contact surface 416, and a second side surface 418. The second inner surface 410 includes a second chamfer 420, abutting and extending from the inner surface 308 of the arch-shaped body 304. The second outer surface 412 is opposite to the second inner surface 410, abutting and extending from the outer surface 310 of the arch-shaped body 304. The second top surface 414 abuts and extends from the top surface 312. The second contact surface 416 is opposite to the second top surface 414, connecting the second inner surface 410 to the second outer surface 412. To form a seal with the first contact surface 324, the second contact surface 416 extends relative to the second top surface 414 at a second angle, which is substantially equal to the first angle. For example, the second angle can be in the range of approximately 5 degrees to approximately 65 degrees. As another example, the second angle can be in the range of approximately 10 degrees to approximately 30 degrees. Therefore, the second contact surface 416 is configured to slidably contact the first contact surface 324 to arrange the oil scraper ring in an overlapping state. The second side surface 418 is generally parallel to the first end face 316.

[0025] The oil scraper ring 130 is in an overlapping state (e.g.) Figure 5-6As shown, the inner surface 308 of the bow-shaped body 304, the first inner surface 320 of the first protrusion 306, and the second inner surface 410 of the second protrusion 404 together define an inner surface 222 extending 360 degrees around the central axis of the oil scraper ring 130. Similarly, the outer surface 310 of the bow-shaped body 304, the first outer surface 322 of the first protrusion 306, and the second outer surface 412 of the second protrusion 404 together define an outer surface 224 extending 360 degrees around the central axis of the oil scraper ring 130. In other words, when the oil scraper ring 130 is positioned within the second annular groove 206 of the piston 126, the outer surface 224 of the oil scraper ring 130 is configured to form a 360-degree contact with the wall 118 of the cylinder 102. Therefore, the outer surface 224 sufficiently restricts the amount of oil flowing from the oil layer 202 into the combustion chamber 136 along the wall 118. Over time, due to contact with wall 118, the lower portion 502 of outer surface 224 (shown as dashed lines) is configured to undergo wear while maintaining 360-degree contact with wall 118. The first groove 330, first side surface 328, second groove 408, and second end face 406 together form a channel 504 to allow fluid (e.g., air, fuel, and / or oil) to flow from inner surface 222 to outer surface 224 of scraper ring 130. By including the first groove 330 and / or the second groove 408 on scraper ring 130, scraper ring 130 is configured to allow fluid flow regardless of the degree of overlap between the first end 302 and the second end 402 of scraper ring 130. For example, even if the first side surface 328 and the second end face 406 are adjacent, fluid can flow through the first groove 330 and / or the second groove 408 to relieve pressure between compression ring 128 and scraper ring 130.

[0026] The scraper ring 130 is formed from a single, integral piece of material (e.g., stainless steel). For fitting within the second annular groove 206 of the piston 126, the diameter of the inner surface 222 of the scraper ring 130 can range from approximately 50 mm to approximately 600 mm. As an example, the diameter of the inner surface 222 can range from approximately 150 mm to approximately 175 mm. The radial width of the uppermost surface 226 and / or the lowermost surface 228 of the scraper ring 130 is greater than the distance between the outer surface of the second piston ring land 212 and the wall 118. For example, the width can range from approximately 2 mm to approximately 25 mm. As another example, the width can range from approximately 6 mm to approximately 7 mm. To allow fluid (e.g., an air-fuel mixture) to enter the second annular groove 206 and press against the wall 118 and the second upper surface 218 of the second piston ring land 212 to press the scraper ring 130, the axial height of the inner surface 222 and / or the outer surface 224 is less than the height of the second annular groove 206. For example, the height can range from approximately 1 mm to approximately 15 mm. As another example, the height can range from approximately 3 mm to approximately 4 mm. Other materials and / or dimensions may be considered.

[0027] As mentioned above, providing Figure 3-6 As an example. Other examples can be used with reference to... Figure 3-6 The differences are as described. For example, the number and arrangement of the surfaces can be different from those of the others. Figure 1-2 The difference is shown. Therefore, compared to Figure 3-6 Compared to the examples shown, the surfaces can have additional surfaces, fewer surfaces, and / or different shapes. For example, the first contact surface 324 and the second contact surface 416 can have curved shapes, stepped shapes, serrated shapes, or any shape that allows the first contact surface 324 and the second contact surface 416 to slide relative to each other when forming a seal. As another example, the scraper ring 130 may include only one of the first groove 330 or the second groove 408, which may have different shapes (e.g., chamfered cross-section, triangular cross-section, non-linear sides, etc.), may be provided at different and / or additional portions of the scraper ring 130, and / or may additionally or alternatively be provided within the second upper surface 218 of the second piston ring land 212. For example, in some embodiments, the second upper surface 218 may include one or more radially extending grooves having substantially the same structure and flow function as the first groove 330 and the second groove 408. As another example, the outer surface 224 of the scraper ring 130 may be at an angle relative to the bottom surface 314 (e.g., at an 80-degree angle, at a 60-degree angle, etc.). In such an example, the lower portion 502 of the outer surface 224 may be further configured to withstand wear while maintaining 360-degree contact with the wall 118.

[0028] Industrial applicability

[0029] The oil scraper ring 130 of the present invention is particularly suitable for systems that include a movable connection between two fluid chambers, such as a power system 100. The power system 100 may be implemented in a vehicle (e.g., a motor vehicle, a rail vehicle, a ship, an aircraft), a generator, or similar machine.

[0030] Due to the structure and arrangement of the oil scraper ring 130 relative to the piston 126, the oil scraper ring 130 offers several advantages. For example, because the first end 302 and the second end 402 of the oil scraper ring 130 are configured to slidably overlap, the outer surface 504 forms a 360-degree contact with the wall 118 of the cylinder 102. Therefore, the oil scraper ring 130 effectively limits the amount of oil flowing directly from the oil layer 202 into the combustion chamber 136. Thus, compared to a typical open ring, the oil scraper ring 130 improves the performance of the powertrain 100 by reducing oil volume, surface deposits, emissions, and / or reducing the likelihood of unintended combustion during charging. Furthermore, by including the first groove 330 and / or the second groove 408, the oil scraper ring 130 allows any fluid (e.g., air, fuel, and / or oil) trapped between the compression ring 128 and the oil scraper ring 130 to flow. This flow is advantageous because without it, the pressure between the compression ring 128 and the oil scraper ring 130 can sometimes exceed the pressure in the combustion chamber 136, causing fluid to enter the combustion chamber 136.

[0031] The foregoing disclosure provides explanation and illustration, but is not intended to be exhaustive or to limit the embodiments to the precise forms disclosed. Improvements and modifications can be made based on the foregoing disclosure, or improvements and modifications can be obtained from the implementation of the embodiments. Furthermore, any embodiments described herein can be combined unless the foregoing disclosure explicitly states a reason why one or more embodiments cannot be combined. Although specific combinations of features are stated in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of different embodiments. Although each dependent claim listed below refers to only one claim, the disclosure of each embodiment includes the possibility that each independent claim can be combined with each of the other claims in the claim book.

[0032] The indefinite articles “a,” “an,” and “set” used herein are interchangeable with “one or more.” Furthermore, the definite article “the” used herein is intended to include one or more items mentioned in relation to “the” and is interchangeable with “the one or more.” Additionally, the phrase “based on” is intended to mean “at least partially based on” unless explicitly stated otherwise. Furthermore, the expression “or” used herein, when used in a series, is intended to include everything and is interchangeable with “and / or” unless explicitly stated otherwise (e.g., when used in combination with “or” or “only one of”). Additionally, for ease of description, spatial relational expressions such as “below,” “under,” “above,” “on top,” etc., are used herein to describe the relationship of one element or feature relative to another element (or other elements) or feature (or other features) (as shown in the figures). Spatial relational expressions are intended to include, in addition to the positioning shown in the figures, different positioning of devices, equipment, and / or elements during use or operation. Devices may be positioned in other ways (rotated 90 degrees or other positioning), and the spatial relational expressions used herein are interpreted accordingly.

Claims

1. An oil scraper ring for a piston, comprising: An arc-shaped body, the arc-shaped body including an inner surface, an outer surface, a first end face connecting the inner surface to the outer surface, and a second end face opposite to the first end face. The first protrusion extends circumferentially from the first end face. Wherein, the first protrusion includes a first inner surface, a first outer surface, a first contact surface connecting the first inner surface to the first outer surface, a first bottom surface, and a first side surface; and The second protrusion extends circumferentially from the second end face. The second protrusion includes a second inner surface, a second outer surface, and a second contact surface connecting the second inner surface to the second outer surface; Wherein, the first contact surface is configured to slidably contact the second contact surface to adjust the diameter of the oil scraper ring; and Wherein, when the first contact surface contacts the second contact surface The inner surface, the first inner surface, and the second inner surface together define the inner surface of the scraper ring that extends 360 degrees relative to the central axis of the scraper ring. The outer surface, the first outer surface, and the second outer surface together define the outer surface of the scraper ring extending 360 degrees relative to the central axis; and The first protrusion includes a first groove and the second end face includes a second groove, and the first groove, the first side face, the second groove and the second end face together form a channel to allow fluid to flow from the inner surface to the outer surface of the oil scraper ring.

2. The oil scraper ring according to claim 1, wherein, The bow-shaped body further includes: Connect the inner surface to the bottom surface of the outer surface, and The top surface opposite the bottom surface; The first protrusion further includes a first bottom surface substantially coplanar with the bottom surface; and The second protrusion further includes a second top surface that is substantially coplanar with the top surface.

3. The oil scraper ring according to claim 2, wherein, The first contact surface extends at a certain angle relative to the first bottom surface; and The second contact surface extends relative to the second top surface at the angle stated therein.

4. The oil scraper ring according to claim 3, wherein, The angle is in the range of approximately 10 degrees to approximately 30 degrees.

5. The oil scraper ring according to any one of claims 2-4, wherein The groove extends along the first bottom surface of the first protrusion between the first inner surface and the first outer surface of the first protrusion.

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