A piston head for a die-casting machine, in particular a cold chamber type, comprises a front surface for pushing the molten metal and a side wall extending around a head axis, wherein at least one ring seat is provided in said side wall suitable to receive a sealing ring. The bottom of the ring seat is connected to the front surface through holes or connection channels for a metal flow under the sealing ring. The holes or connection channels lead into an annular peripheral portion of said front surface, said annular peripheral portion being inclined with respect to a front plane orthogonal to said head axis so as to be turned towards said head axis.

A high pressure fuel pump includes a pumping head and a plunger slidably adjusted in a bore. The plunger is provided with a blind bore defining a chamber open in the head end of the plunger and in fluid communication with the compression chamber, the end face of the plunger being limited to a peripheral annular face surrounding the opening, the bore further defining a peripheral cylindrical wall and a bottom face. A filler member is arranged inside the chamber.

The present disclosure provides a sealing ring assembly with one or more piston-integrated gap cover features, configured to seal a high-pressure region from a relatively lower pressure region of a piston and cylinder device. The sealing ring assembly may include two rings which each may include one or more ring segments. The one or more gap-cover features, which may be in the form of protrusions in the piston ring groove, may engage with corresponding flat sections of the ring segments. As the sealing ring wears, the gap-cover features may stay engaged with the ring segments, thereby maintaining a seal.

A device includes an outer cylinder having a cylinder inner wall and a cylinder outer wall and at least one magnet disposed on or between the cylinder inner wall and the cylinder outer wall and a piston having a piston inner wall and a piston outer wall and at least one magnet disposed on or between the piston outer wall and the piston inner wall. In one embodiment, the piston is rotatable within the cylinder and slidably movable along an axis respective to the cylinder. The piston is also disposed within the cylinder such that the at least one magnet disposed on or between the cylinder inner wall and the cylinder outer wall is aligned with the at least one magnet disposed on or between the piston outer wall and the piston inner wall, substantially preventing the piston from rotating relative to the cylinder.

A method for fabricating a piston with a layering device via an additive manufacturing process is provided. The method may include forming a first layer of the piston on a substrate with a layering device, forming a second layer of the piston adjacent the first layer with the layering device, and binding the first layer with the second layer. The first layer of the piston may include a first material, and the second layer of the piston may include the first material and a second material.

The present disclosure describes composite actuator piston rods and methods for making such rods. Composite actuator piston rods of the present disclosure may include a composite actuator rod tube having a flared end, an insert, wherein the insert has a complementary shape to the flared end, a piston head concentrically surrounding the flared end of the composite actuator rod tube, and a piston head nut configured to threadingly attach to the piston head.

Provided are a disc brake and a piston whose weights can be effectively reduced. A disc brake includes a piston configured to press a pad against a disc. The piston includes a body member formed into a bottomed cylindrical shape and including a cylinder portion and a bottom portion. The cylinder portion and the bottom portion are approximately equal in wall thickness. The piston further includes a plate-shaped member fixed to an external bottom surface of the body member and disposed within a range of the external bottom surface and in a region including a center of the external bottom surface.

A brake cylinder piston assembly having a composite piston head having a bore formed therethrough, a cup positioned in the bore and coupled to the piston head, and a hollow rod securely welded to the cup. The cup is coupled to the piston head by a series of fingers with locking tabs that extend around the bore of the piston head and engage a rim of the cup. The bore of the piston head has two steps that correspond to the two steps formed into outside of the cup so the two step outer diameter of the cup is securely seated in the two step inner diameter of the bore. A plastic load disc having a hemispherical cavity may be positioned within the end of the hollow rod that is secured to the cup to absorb high energy hand brake releases.

A piston assembly comprises a piston body, a connecting rod, and a wrist pin. The piston body includes a pair of first cross bores presenting a piston sliding surface. The connecting rod includes a second cross bore presenting a rod sliding surface which is axially aligned with the first cross bores of the piston body. A wrist pin is disposed in the aligned cross bores and couples the piston body to the connecting rod. The wrist pin also presents a pin sliding surface facing the rod sliding surface and the piston sliding surfaces. A coating is applied to at least one of the sliding surfaces, such as by dipping, brushing, atomizing, spraying, printing, or screen printing. The coating includes a polymer matrix, such as polyamide imide (PAI), and hard particles, such as Fe.sub.2O.sub.3, disposed throughout the polymer matrix. The hard particles have a hardness of at least 600 HV/0.5.

A pump is disclosed. The pump may include at least one pumping mechanism. The at least one pumping mechanism may include a barrel formed of a substrate having a bore and a plunger formed of a substrate and slidably disposed within the bore in the barrel. The pump may further include a coating disposed on the plunger. The coating may include a main layer containing a tribological material and a sacrificial break-in layer disposed on the main layer, the break-in layer containing a tribological material.