3461 results about "Piston ring" patented technology

A piston ring has a diamond-like carbon film formed in a thickness of 0.5 to 30 micrometers over an under film on the upper and lower surfaces. The under film is directly formed on the surfaces, or formed on a hard surface treatment layer consisting of a gas nitrided layer or a chromium plating film. The diamond-like carbon is configured with any one of an amorphous carbon structure, an amorphous carbon structure having partly a diamond structure, or an amorphous carbon structure having partly a graphite structure. The under film is comprised of one or more elements selected from the group consisting of silicon, titanium, tungsten, chromium, molybdenum, niobium and vanadium in an atomic content of 70 percent or more and below 100 percent, and the remaining content consisting of carbon, or one or more of said elements in an atomic content of 100 percent. The films may also be formed in the same way on the outer circumferential surface of the piston ring.

A method for improving efficiency and reducing emissions of an internal combustion engine. Variable displacement engine capabilities are achieved by disabling engine valves during load changes and constant load operations. Active cylinders may be operated at minimum BSFC by intermittently disabling other cylinders to provide the desired net torque. Disabling is begun by early closing of the intake valve to provide a vacuum at BDC which will result in no net gas flow across the piston rings, and minimum loss of compression energy in the disabled cylinder; this saving in engine friction losses is significant with multiple disablements.

There is provided a cylinder device having optimal arrangement of fine textures and optimal surface roughness capable of reducing wear of a cylinder bore side and a piston ring by processing fine textures in an optimal selection region of the cylinder bore side to improve lubrication characteristics between the piston ring and the cylinder bore side while reducing engine oil consumption by processing surface roughness of the cylinder bore side to an optimal status.

A piston for an internal combustion engine of an automotive vehicle. The piston has a piston ring and a piston skirt section each of which has a sliding section in slidable contact with a cylinder bore section of a cylinder block in presence of a lubricating oil. The cylinder bore section is formed of eutectic or hyper-eutectic aluminum alloy. Additionally, a hard carbon thin film is coated on the sliding section of the piston and contains hydrogen atom in an amount of not more than 1 atomic %. Here, the lubricating oil contains at least one selected from the group consisting of ashless fatty acid ester friction modifier, ashless aliphatic amine friction modifier, polybutenyl succinimide, derivative of polybutenyl succinimide, zinc dithiophosphate, and derivative of zinc dithiophosphate.

The invention discloses a full automatic grinding machine for a piston ring inclined end surface. The full automatic grinding machine comprises a machine bed, an automatic loading and unloading rack, a composite processing table, a power head rack, a material collection rack and two parallel guide rails which are arranged on the machine bed, wherein the automatic loading and unloading rack and the composite processing table are arranged on the two ends of the two guide rails, the power head rack and the material collection rack are arranged on the two sides of the two guide rails; the automatic loading and unloading rack comprises a material storage rack, a material delivering slide table and a material delivering cylinder, the composite processing table comprises a processing slide table and a slide table displacement servo motor; the power head rack comprises a shell, a hollow axle pipe is arranged in the shell, an electromagnetic chuck and a positioning disk are sleeved on one end of the axle pipe near to the guide rail, and the material storage rack comprises a material storage rod, a guide rod and two inverted L-shaped connection racks. The piston ring inclined end surface is more simply processed, the processing precision is high and the processing efficiency is high.

The invention discloses a friction and abrasion testing method and equipment of cylinder piston ring element in the friction and abrasion testing technique domain, which is characterized by the following: adapting mechanic radial loading construction method and equipment to test the cylinder and piston ring element; adding liquid through heating the cylinder cavity to keep thermal; fixing the friction force sensor on the test machine rack directly; eliminating the measuring result influence of friction force by inertia force of moving component to gain more precise friction force; segregating the friction force sensor and cylinder through thermal-insulation material; setting the cooler to prevent the rack temperature from elevating and the temperature of friction force sensor from exceeding the highest working temperature. The invention is used as the rapid assessment method in the lab developing procedure of cylinder piston ring.

A piston ring for internal combustion engines with a coating of Chromium nitride (CrN) deposited by a physical vapor deposition process on a sliding surface with a typical crystal structure of CrN phase, has a high wear resistance and superior resistance to the generation of micro-cracks and consequent localized loss of pieces of the coating. The coating is a columnar crystalline coating of CrN having a dispersed pore content lower than 10% in volume and ratio of intensities, measured through x-ray diffraction, between the crystal planes (111) and planes (200), parallel to the surface, in the range of 0.40 to 0.70. This crystalline distribution is obtained through an oxygen content impregnated in the CrN coating between 1.0% in weight to 7.0% in weight. The Vickers hardness of the film ranges from 1,500 to 2,200 HV.

A sliding element, in particular piston ring, has on at least one running surface, from the inside outwards, a coating having a metal-containing adhesive layer and a ta-C type DLC layer with a thickness of at least 10 μm.

In a process for the production of a sliding element, in particular a piston ring, coating with a metal-containing adhesive layer and a ta-C type DLC layer in a thickness of at least 10 μm is carried out.

The disclosed is a combination of a cylinder liner and a piston ring which contacts to a inner circumference surface of the cylinder liner at the pressure of 0.03 to 0.2 MPa, wherein the composition of the cylinder liner includes, silicon: 23.0 to 28.0% by weight, magnesium: 0.80 to 2.0% by weight, copper: 3.0 to 4.5% by weight, iron: 0.25% by weight or less, nickel: 0.01% by weight or less, and the rest: unavoidable impurities and aluminum, and wherein surface roughness profile of the inner circumference surface has Rz 0.5 to 1.0 μm, Rk=0.2 to 0.4 μm, Rpk=0.05 to 0.1 μm, Rvk=0.08 to 0.2 μm, meanwhile, wherein the composition of a piston ring includes carbon: 0.6 to 0.7% by weight, chrome: 13 to 14% by weight, molybdenum: 0.2 to 0.4% by weight, silicon: 0.25 to 0.50% by weight, manganese: 0.2 to 0.5% by weight, and the rest: unavoidable impurities and iron, and wherein carbides with the diameter of 5.0 μm and less are contained at the area rate of 4 to 10%, and the surface roughness of an outer circumference sliding surface is Rz=0.8 μm or less, and RPk=0.15 μm or less.

The invention provides a friction and abrasion tester for reciprocating piston ring-cylinder liner. The invention relates to the technical field of mechanism friction and abrasion, in particular to a friction and abrasion tester for reciprocating piston ring-cylinder liner as a friction paring element practically applied in an internal-combustion engine. A motor driven crankshaft connecting rod mechanism of the tester moves in linear reciprocation through a slide block and a guide sleeve of a guide mechanism, a loading system adopts extrusion-high strength bolting structure to change the pressure from a piston ring of the high strength bolting to the cylinder liner, a lubricator and an oil collector of a lubricating device are positioned on the loading mechanism corresponding to the position of the cylinder liner, sensors of a friction tester and a temperature measurement and a control device are connected to a data collecting card of a data collecting and monitoring device and a computer through interfaces. The invention adopts the practically applied piston ring-cylinder liner of an internal-combustion engine as a friction paring element, load, speed, temperature, lubricant supply experimental parameters can be changed; the invention can monitor temperature, friction experimental data and process experimental data.

A lubrication system having an oil filter modified to replace or supplement the performance of lubricant additives that may be used within an internal combustion engine to increase the performance of a lubricant. The formulation of the lubricant is changed in accordance with the chemicals placed in the oil filter. For example, when the oil filter contains a strong base, the lubricant concentration of detergent will decrease, in some cases to zero, while the dispersant concentration in the lubricant will increase. The dispersant is the ideal weak base to neutralize combustion acid at the piston ring zone, carry the resultant weak base-combustion acid complex to the strong base in the oil filter, undergo ion exchange with the strong base, immobilize the acid in the oil filter and recycle back to the piston ring zone for reuse as an acid neutralization agent. The reduction or elimination of detergent from the lubricant will reduce the fouling of the emission filter and of deposit formation on engine parts such as the piston. The oil filter may also contain an additive which is slowly released into the lubricant. For example, a ZnDDP anti-wear additive may be slowly released from the oil filter to the lubricant. Because the ZnDDP has low molecular weight alkyl groups it has limited solubility in the lubricant. The rate of release is limited by the equilibrium concentration of the additive in the lubricant. As a result, a relatively constant concentration of the additive may be maintained in the lubricant. The resultant closed system allows the oil drain intervals to be significantly extended.

A tester used for simulating wear-out and vibration of main movable parts on internal combustion engine consists of master driving system formed by air cylinder, piston ring, piston, crankshaft, inlet and outlet of high pressure air; state monitoring system formed by pressure transducer and vibration transducer on bearing base, oil monitoring transducer and temperature transducer as well as vibration transducer on machine rack, and dynamic transducer on crankshaft. It is featured as utilizing high pressure air to simulate explosion pressure in air cylinder and to simulate operation condition causing wear-out and vibration of cylinder sleeve and piston ring pair in said engine.

The invention relates to a piston ring for internal combustion engines, the piston ring comprises a steel or cast iron base material with a coating of chromium nitride deposited by a physical vapor deposition process on a sliding surface of the piston ring, wherein the coating is composed of a columnar crystal structure of CrN with the following features:

• • (a) an oxygen content in solid solution of 0.5 to 2.5 wt %;
  • (b) a content of uniformly dispersed micro-pores of less than 10% in volume of the coating; and
  • (c) an X-ray diffraction intensity ratio of (111) planes to (200) planes parallel to the surface in the range of 0.80 to 1.20.

A variable-load cylinder-sleeve piston-ring frictional wear testing device is mainly composed of a main shaft motor, a guide rail, a sliding table, left and right uprights, a work table, a lever, a loading rod, a swing limiter, a load changer, an inner concave cambered-surface lower clamp and an outer convex cambered-surface upper clamp. An alternating force is generated by the load changer, and then is amplified by the lever to act on a test piece, thereby realizing radial loading of a piston ring to a cylinder sleeve; a variable load is measured in real time by a pressure sensor between theload changer and the lever; friction is measured by a foil gauge on the loading rod; the swing amplitude of the lever is reduced by the swing limiter; the loading rod comes into contact with the outer convex cambered-surface upper clamp through a ball pair to guarantee that the loading direction is vertically downward; the rotating speed of the motor is controlled by means of a program so as to carry out frictional wear tests at different speeds. The testing device is simple in structure, various in testing functions and high in accuracy.

A laser-welded single-piece forged-steel piston with an enclosed inner oil cooling chamber having the advantages of simple structure and easy manufacturing process, and capable of satisfying the requirement of engines for high power, high rigidity, and low discharge development, and its manufacturing process. The laser-welded single-piece forged-steel piston of the invention comprises a piston body member and a piston ring member, wherein the piston body member is welded together with the piston ring member through laser welding procedure, an enclosed inner oil cooling chamber is formed between the piston body member and the piston ring member, and is connected with the piston inner cavity by means of at least two oil inlet/outlet holes, and a pin hole is opened at the lower portion of the piston body member.

A cylinder realizing reduced reciprocation friction between a piston ring and a bore surface of the cylinder in a region where the piston ring slides. The cylinder in which a piston slides on a bore surface of the cylinder. A plurality of recesses is formed in a stroke center region in the bore surface of the cylinder. The stroke center region is a region between an under face position of a ring groove for a bottom piston ring at a top dead center of the piston and a top face position of a ring groove for a top piston ring at a bottom dead center of the piston. The total of areas of all of the recesses is in the range of 1% to 80% when an area of the stroke center region is 100%, and the recesses are not formed in a region other than the stroke center region of the bore surface of the cylinder.

The invention relates to an automatic light leakage degree and closed gap detector of a three-station piston ring and a calibrating block thereof. A horizontal workbench is formed at the top of a stand, and is provided with a cantilever beam, a touch screen connected to the cantilever beam, a storage mechanism for storing the piston ring, a push plate positioned below the storage mechanism and a round turntable which is arranged in front of the storage mechanism and the push plate and rotatably inlayed on the horizontal workbench; a separation mechanism is arranged in front of the round turntable; a closed gap detection station, a discharge station and a light leakage degree detection station are formed on the round turntable by three inlayed standard gauges; a first charge coupled device (CCD) sensor corresponding to the closed gap detection station and a second CCD sensor corresponding to the light leakage degree detection station are respectively arranged above the horizontal workbench; and a light leakage degree detection illumination mechanism is arranged at the position below the horizontal workbench, corresponding to the light leakage degree detection station. By adopting the detector and the calibrating block, high efficiency, and the automatic detection and the separation of two indexes of the light leakage degree and the closed gap of small and medium sized piston rings are realized.

An object of the present invention is to provide a cylinder structure reduced in mutual damage caused by a sliding operation of a piston ring and a cylinder liner when the piston ring having a linear expansion property which follows linear expansion of the cylinder liner made of an aluminum alloy is used. In order to achieve the object, a combination structure of the piston ring and the cylinder liner for an internal combustion engine described below is employed. In the cylinder liner for an internal combustion engine, the inner circumferential surface satisfies the conditions, a ten-point height of roughness profile (Rz_JIS94) of 0.5 μm to 1.0 μm, a core roughness depth (Rk) of 0.2 μm to 0.4 μm, a reduced peak height (Rpk) of 0.05 μm to 0.1 μm and a reduced valley depths (Rvk) of 0.08 μm to 0.2 μm. In the piston ring, the sliding surface against to an inner circumferential surface in the cylinder liner satisfies the conditions, a ten-point height of roughness profile (Rz_JIS94) of not more than 1.6 μm and a reduced peak height (Rpk) of not more than 0.3 μm. The piston ring is used at a contact pressure of 0.03 MPa to 0.2 MPa against to the inner circumferential surface of the cylinder liner.

A piston ring is provided at its outer periphery with a sliding surface, wherein in a cross section thereof which is perpendicular to a radial direction of the piston ring, the sliding surface includes a first sliding surface which occupies a predetermined region from one end thereof, and a second sliding surface which occupies a region extending from one end to the other end of the first sliding surface, the first sliding surface is formed of hard film, the second sliding surface is not formed of hard film, and the second sliding surface exists at a position deviated inward from a phantom line extending from the first sliding surface toward the other end.

An amorphous hard carbon film has low friction coefficient from the beginning of sliding, when the metal oxide is contained in the film. The adhesion of the film to the substrate is also improved due to the low temperature treatment of RF plasma enhanced CVD method. This film can be applied to many sliding members, e.g., a piston ring, a vane of compressor and a plunger of fuel injection pump, used under severe condition.

A cylinder is divided into two chambers by a wall to receive a pair of pistons. This reduces the stroke length and correspondingly reduces the linear speed of the piston. This leads to a reduced PV factor associated with degradation and wear of the piston rings. Moreover, the multi-cylinder arrangement provides the same performance in an oil-free compressor assembly without appreciably expanding dimensional constraints relative to known systems.