Abstract:
The external profile of a piston rod employed in the engines of passenger cars ensures smoother piston travel on start-up and during partial loading. In these operating ranges, piston ring parts may impact on the sliding surface of the cylinder on the counter-pressure side and give rise, amongst others things, to undesirable noise. To obviate such impacts, the piston rod tapers at the end facing the crankshaft space on the counter-pressure side, and has a transversal slit (3) at its junction with the piston head and an adjustment strip (4) in the vicinity of the said slit. An additional adjustable strip (5) may also be provided in the lower part of the rod, on the pressure side. As a result of the position of the adjustment strips, the special design of the piston and the special shape of the rod casing, the piston head aligns itself at a slight angle to the counter-pressure side, with increasing play between the piston head and the sliding surface of the cylinder, in the said operating ranges. When the engine is running at full load, the piston head realigns itself in the direction of its axis.
Abstract:
The technical problem is to reduce the operating noise of such a piston. It is solved by means of a piston having the following dimensions: a) A = (0.45-0.65) D; b) H = (0.25-0.4) D; c) A = (0.3-0.4) D; d) A greater than or equal to B; e) T = (0.45-0.8) D; f) the piston ribs between the annular grooves (2, 3, 4) and the rod region with a very narrow operating clearance have, in the case of a hot operating piston, approximately the same clearance in relation to the cylinder operating path. An additional improvement consists in inserting an annular jacket in the piston head in the radial region behind the annular grooves, said jacket consisting of a material having a thermal expansion factor less than that of the basic piston material. In a hot operating internal combustion engine, the piston has, in the region of the ribs, a clearance which, in the direction pressure/counter-pressure reaches approximately only 3-5 times the clearance in the very narrow clearance region of the piston rod.
Abstract:
Aluminium-based article having a heat and corrosion protective coating, especially engine parts such as piston crown or cylinder head, and a method of preparing said article. The coating consists of an aluminium-based bonding layer, preferably having a thickness in the range 0.1-0.6 mm, and an outer top layer of stabilized or partially stabilized zirconium dioxide, preferably having a thickness in the range 0.5-2.5 mm, and optionally a cermet layer, comprising zirconium dioxide and an aluminium-based metal component, between the bonding layer and the outer zirconium dioxide top layer. The bonding layer is applied to the substrate by thermal spraying of a rapidly solidified powder, substantially consisting of 60-80% by weight of Al and 40-20% by weight of Si, the particles of the powder having a frozen unstable micro-structure. The cermet layer desirably is a layer consisting of zirconium dioxide and an aluminium-based alloy, the metal content of the cermet layer decreasing substantially uniformly in the direction towards the outer zirconium dioxide top layer. The cermet layer preferably has a thickness in the range 0.2-0.6 mm. Also the cermet and zirconium oxide layers are deposited by thermal spraying.
Abstract:
A light metal alloy piston having a reinforcement insert (2) in the top of the crown is made by casting the piston in the crown-down position by introducing the metal alloy (3) above the reinforcement insert (2), which may have anchoring legs (4) with enlarged ends (5), under conditions of heat and pressure so as to cause the piston alloy (3) to form around the reinforcement insert (2), and the legs (4), and promote an intimate bond between the alloy and the insert.
Abstract:
An internal combustion engine comprises a flow control device (6), for controlling the flow of petroleum fuel into the engine, and which comprises regulator elements (18, 19), the relative positions between which controlling the flow rate, the positions of the regulator elements being controlled by an input element (23). The device comprises an adjustment means (30) which can be set to a number of different values, which provide for different response rates of the regulator elements (18, 19) to movement of the input element (23). Liquid fuel is thus injected at a desired rate into a stream of air, utilising a closure member (66) which when the pressure at which fuel is delivered to an outlet nozzle (51) is less than a predetermined value, prevents flow of fuel through the outlet nozzle, and when the pressure at which fuel is delivered to the outlet nozzle exceeds said predetermined value, the closure member moves to open the outlet a distance proportional to the pressure in the outlet nozzle. The engine also comprises a cylinder (110) and a piston (112) slidably mounted in the cylinder. The piston (112) is provided with a cooling passageway (122) which at or adjacent the bottom dead centre position of the piston is aligned with inlet and outlet ports (124, 126) of the cylinder. In the use of the engine, gas, which may be air or a mixture of fuel and air, is caused to flow through the cooling passageway during part at least of the cycle of reciprocation of the piston in the cylinder, to remove heat from the piston (112).
Abstract:
One example of a gerotor pump includes an inner rotor comprising multiple teeth, the inner rotor configured to rotate about a first longitudinal gerotor pump axis. The gerotor pump also includes a hollow outer rotor including an outer surface and an inner surface having substantially identical contours, the inner surface configured to engage with the multiple teeth and to rotate about a second longitudinal gerotor pump axis. The pump includes a pump housing within which the inner rotor and the outer rotor are disposed, wherein the outer surface of the outer rotor defines gaps between the pump housing and the outer rotor.
Abstract:
A steel piston with an oil gallery, and process for forming a steel piston oil gallery channel, which corresponds to the complex shape of the combustion bowl in the piston crown. The oil gallery channel is first forged to the basic shape that corresponds to the shape of the walls of the combustion bowl. Machine-turning surfaces in the oil gallery channel can be machine-finished as desired. Surfaces in the oil gallery which cannot be machined with conventional turning operations, such as recesses and protrusions into the channel, are left in the original forged condition.
Abstract:
Die Erfindung betrifft ein metallisches Gussbauteil (1), das insbesondere für Teile von Verbrennungskraftmaschinen oder Kolbenverdichtern wie Kolben, Getriebegehäuse, Kurbelgehäuse und andere Gehäuse und/oder Zylinderköpfe, vorgesehen ist, wobei das Gussbauteil (1) zumindest abschnittsweise aus einem Eisen-Aluminid besteht und/oder ein Verbundgussbauteil mit zumindest zwei Abschnitten (2, 3) ist, welche aus einem Gusseisen und/oder einem Eisen-Aluminid und/oder einem Leichtmetall bestehen. Die Erfindung betrifft weiterhin ein Verfahren zur Herstellung eines metallischen Gussbauteils (1), insbesondere für Teile von Verbrennungskraftmaschinen oder Kolbenverdichtern wie Kolben, Getriebegehäuse, Kurbelgehäuse und andere Gehäuse und/oder Zylinderköpfe, das aus einem oder mehreren Gusswerkstoffen wie Gusseisen und/oder Eisen-Aluminid und/oder Leichtmetall besteht, bei dem in einem ersten Gussvorgang ein erster Abschnitt (2) des Gussbauteils (1) und in einem weiteren Gussvorgang ein weiterer Abschnitt (3) des Gussbauteils (1) erzeugt wird und bei dem vor dem weiteren Gussvorgang auf den ersten Abschnitt (2) eine Beschichtung, insbesondere aus Eisen-Aluminid und/oder einer Nickel-Legierung, als Haftvermittlerschicht aufgetragen wird.
Abstract:
Vorgeschlagen wird ein Verfahren zur Herstellung eines Kolbens (1) aus Stahl für einen Verbrennungsmotor, bei dem das Kolbenoberteil (3) im Schmiedeverfahren und das Kolbenunterteils (4) im Schmiede- oder Gießverfahren hergestellt und anschließend miteinander verschweißt werden. Zur Vereinfachung und Verbilligung des Herstellungsverfahrens wird das Kolbenoberteil mit Hilfe des Verfahrens des Warmumformens und des Kaltkalibrierens insoweit fertig geschmiedet, dass eine weitere Bearbeitung der Verbrennungsmulde und des oberen Kühlkanalbereichs entfallen kann.