A rotary compressor or pump has a cam with a plurality of lobes mechanically engaging a plurality of pistons. The lobes urge the pistons from an open to a closed position within a piston void, the closure of the piston into the piston void creating compression or pressure of a material. Each piston is linked to another piston, and as one piston is closed by the cam, the other piston is opened by a linkage.

A high-pressure fuel pump includes a pump body, a plunger, a retainer, a spring that is configured to energize the plunger in a direction opposite to a direction of the pressurizing chamber, and a tappet covering the retainer from a side of an end portion of the retainer and the plunger. The retainer is provided with a projection portion protruding to a side of the tappet. The projection portion is separated from the tappet by a predetermined distance along an axial direction of the plunger.

A piston type pump includes a pump housing having a pump inlet, a pump outlet, and a piston arrangement connected to a drive shaft. The drive shaft is configured to drive the piston arrangement, and the drive shaft includes a first eccentric. The piston arrangement has a first primary stage piston connected to a first sliding block guide slidably seated on the first eccentric. The first sliding block guide has a main axis, a minor axis, and an inner surface. A first sliding bush is arranged between the first eccentric and the first sliding block guide. The outer surface of the first sliding bush corresponds to the inner surface of the first sliding block guide. Translational movement of the first sliding bush relative to the first sliding block guide is allowed along the main axis and restricted along the minor axis.

A piston type pump includes a pump housing having a pump inlet, a pump outlet, and a piston arrangement connected to a drive shaft. The drive shaft is configured to drive the piston arrangement, and the drive shaft includes a first eccentric. The piston arrangement has a first primary stage piston connected to a first sliding block guide slidably seated on the first eccentric. The first sliding block guide has a main axis, a minor axis, and an inner surface. A first sliding bush is arranged between the first eccentric and the first sliding block guide. The outer surface of the first sliding bush corresponds to the inner surface of the first sliding block guide. Translational movement of the first sliding bush relative to the first sliding block guide is allowed along the main axis and restricted along the minor axis.

A fluid pump includes: three or more volume chambers that suction and discharge a fluid sequentially; moving elements that are respectively provided in the volume chambers, move relative to the volume chamber, and suction and discharge the fluid from and to the volume chamber; a cam that abuts against and drives the moving elements; and a driving section that drives at least one of the moving elements and the cam and relatively rotates the moving elements and the cam to discharge the fluid one time from each of the volume chambers in one cycle of the relative rotation, in which, when suctioning and discharging the fluid, regarding a discharge rotation angle α, α=(Z/M)×N is satisfied, where the number of volume chambers is M and any integer from 2 to (M−1) is N.

A fluid pump includes: three or more volume chambers that suction and discharge a fluid sequentially; moving elements that are respectively provided in the volume chambers, move relative to the volume chamber, and suction and discharge the fluid from and to the volume chamber; a cam that abuts against and drives the moving elements; and a driving section that drives at least one of the moving elements and the cam and relatively rotates the moving elements and the cam to discharge the fluid one time from each of the volume chambers in one cycle of the relative rotation, in which, when suctioning and discharging the fluid, regarding a discharge rotation angle α, α=(Z/M)×N is satisfied, where the number of volume chambers is M and any integer from 2 to (M−1) is N.

A roller tappet for a fuel pump is provided that has a guide housing which includes a drive-side and output-side section of the same external diameter, and a separate support body extending longitudinally through the guide housing. An upper face on the drive-side section carries a pin with a roller thereon. A lower face of the output-side section interacts at least indirectly with an arrangement for a pump piston. The drive-side section and the output-side section are axially spaced rings connected to one another via the support body. The support body has a first ring area with the upper face and a second ring area with the lower face. The first ring area is connected to an inner jacket of the drive-side section and the second ring area is connected to an inner jacket of the output-side section.

A roller tappet, in particular for a high-pressure fuel pump, is provided that is guided in the direction of the longitudinal axis thereof in a housing receptacle and is driven translatably in the longitudinal direction by cams of a camshaft. The roller tappet has a tappet body. This tappet body has a tappet skirt, a pump piston contact point (9), and a rotatably mounted roller (4), by which the roller tappet is supported on the camshaft. The tappet body has a guide cylinder (1), which is mounted in the housing receptacle and on which the roller (4) is supported, and a cup-shaped sleeve (7) having the pump piston contact point (9), which cup-shaped sleeve is supported in the guide cylinder (1) by a radial ring (8). A cylindrical constriction (5) is formed in the guide cylinder (1) in the region of the radial ring support.

A roller tappet for a fuel pump is provided that has a guide housing which includes a drive-side and output-side section of the same external diameter, and a separate support body extending longitudinally through the guide housing. An upper face on the drive-side section carries a pin with a roller thereon. A lower face of the output-side section interacts at least indirectly with an arrangement for a pump piston. The guide housing includes a drive-side section and an output side section that are separate, axially spaced rings connected to one another via the support body. The support body has a first ring area with the upper face and a second ring area with the lower face. The first ring area is connected to an inner jacket of the drive-side section and the second ring area is connected to an inner jacket of the output-side section.

A tappet assembly (100) used in mechanical equipment includes a tappet body (108) having a cylindrical shape and including a lower carrier portion (152) and an upper shell portion (158) having a cavity (150) defined by an inner wall (160) of the upper shell portion (158) and a top surface (154) of the lower carrier portion (152). The lower carrier portion (152) and the upper shell portion (158) are integrally formed as a single-piece unit. A post (162) extends upwardly from the top surface (154) of the lower carrier portion (152) and is configured to reduce a peak contact pressure associated with the tappet body (108).