A scroll compressor includes a drive bush disposed in one end portion in an axial direction of a main shaft, and configured to be eccentrically rotated in accordance with rotation of the main shaft, a pair of angular bearings arranged back-to-back, and respectively clearance-fitted to an outside of the drive bush, a compression unit that has a boss portion which protrudes from an end plate of a movable scroll and in which the angular bearings are interference-fitted to an inner peripheral surface of the boss portion, and a preload application unit configured to apply a preload to the angular bearings in a direction in which the angular bearings are configured to move toward each other.

A scroll fluid machine that attenuates the bending stress applied to the base of a wall body having an inclined section. The scroll fluid machine is provided with a wall body inclined section in which the distance between the facing surfaces of an end plate of a fixed scroll and an end plate of a rotating scroll that face each other continuously decreases from the outer circumferential side toward the inner circumferential side. A mesh clearance that is a gap between wall bodies formed when the wall bodies mesh with each other is larger on the outer circumferential side of the inclined section than on the inner circumferential side of the inclined section. The mesh clearance is made larger by drawing the wall surface of a wall body further back toward the central side of the wall body in the thickness direction than the original wall surface profile thereof.

A low cost scroll device and methods of manufacturing the same are described. The scroll device includes, for example, a drive pin hole and bearing bores machined into a scroll of the scroll device from the same side as the involute of the scroll; idler shaft assemblies with no more than one bearing in the orbiting scroll for mechanically coupling the orbiting scroll to the fixed scroll; and an epoxy coating applied using a process that requires assembly of the scroll device only once.

A scroll compressor includes fixed and orbiting scrolls, and satisfies at least one of a first condition and a second condition. In the first condition, a first gap between a distal end of the first wrap and the second base changes heading from an outer peripheral side of the first wrap to an inner peripheral side. In the second condition, a second gap between a distal end of the second wrap and the first base changes heading from an outer peripheral side of the second wrap to an inner peripheral side. A rate of change in the first gap in one area is greater than a rate of change in the first gap in another area. A rate of change in the second gap in one area is greater than a rate of change in the second gap in another area.

A gear pump includes: an inner rotor having external teeth; an outer rotor having a tubular inner housing portion in which the inner rotor is rotatably housed in an eccentric state, and internal teeth meshing with the external teeth; a first core having a tubular rotor housing portion in which the inner and outer rotors are housed, and a flange portion projecting radially outward from a tube wall of the rotor housing portion; a board-shaped second core having a contact portion in contact with the flange portion in an axial direction, and closing an opening of the rotor housing portion; and a housing opposing the second core and made of a resin. A gap is formed between opposing surfaces of the second core and the housing in a state where the flange portion is in contact with the contact portion and the housing opposes the second core.

The present disclosure provides a system and method for inspecting and analyzing a pump rotor, such as a progressive cavity pump rotor, by moving a laser that illuminates a surface of the pump rotor along a length of the pump rotor and determining distances from various surfaces of the pump rotor relative to a datum, such as a receiver of reflected radiation from the laser, along the length of the pump rotor. The pump rotor can be rotated relative to the laser, so that the laser can be used in determining multiple peripheral surfaces of the pump rotor to form a cross sectional shape, a longitudinal alignment of the pump rotor surfaces, or a combination thereof.

High pressure injection apparatus (2) for addition of a liquid formulation into a melt stream comprises a first pump which is arranged to accurately meter the liquid formulation (including highly loaded formulations comprising solids comprising particles of relatively large size) and a second pump which boosts the pressure of the formulation to that of the melt stream into which it is to be injected. In an embodiment, the apparatus includes a tank (4) for initially receiving liquid formulation. The tank is subjected to ambient temperature and pressure and need not be stirred or otherwise agitated. The tank is arranged to deliver the formulation via pipe (6) into a first pump (8) (which may be a diaphragm pump or a progressing cavity pump). The pump is arranged to work at a pressure up to 120 bar to boost pressure. Downstream of pump (8), a pipe (10) is arranged to deliver formulation from the pump (8) to a gear pump (12), driven by a motor (13). The gear pump acts to meter the liquid formulation. In an alternative embodiment, apparatus may include a progressing cavity pump to meter formulation and a gear pump to increase pressure. The apparatus may be used to inject a fluid formulation into a melted polymeric material.

A scroll vacuum pump includes an orbiting scroll having a wall extending axially from an orbiting scroll base towards a fixed scroll, the fixed scroll having a fixed scroll wall extending axially from a fixed scroll base towards the orbiting scroll; an axially extending drive shaft having an eccentric shaft portion so that rotation of the eccentric shaft portion imparts an orbiting motion to the orbiting scroll relative to the fixed scroll; and an axial thrust bearing arrangement including an array of ball bearings for bearing against the orbiting scroll base in an axial direction, each ball bearing describing a circular path over the orbiting scroll base during orbiting motion; at least one thrust surface for bearing against the array of ball bearings; and an adjustment mechanism for adjusting the axial position of said at least one thrust surface and thereby the axial position of the orbiting scroll base.

A commutator/manifold assembly controls a flow of hydraulic fluid in a hydraulic fluid system. The assembly includes a commutator having an offset design including an inner portion eccentrically encompassed within an outer portion, and offset commutator porting to control the hydraulic flow. A manifold includes manifold ports having a straight configuration by which walls defining the manifold ports run substantially along a longitudinal axis through an entirety of the manifold. The commutator is configured to rotate to sequentially align the commutator porting with differing portions of the manifold ports to control the flow. The commutator porting includes inner ports and outer ports that are isolated from each other by a commutator seal. A commutator ring has a guiding surface that guides rotation of the commutator. The rotation of the commutator provides a timed flow through the manifold ports straight through the manifold and without any directional flow restriction.

In a scroll compressor (1) provided with a fixed scroll (3) and an orbiting scroll (5), an inclined portion is provided in which the inter-facing surface distance (L) between an end plate (3a) and an end plate (5a) that face each other decreases continuously from the outer peripheral side towards the inner peripheral side. The inclined portion is configured from wall inclined portions (3b1, 5b1) in which the height of a wall (3b, 5b) decreases continuously from the outer peripheral side towards the inner peripheral side, and end plate inclined portions (3a1, 5a1) in which a tooth bottom surface is inclined in accordance with the incline of the wall inclined portions (3b1, 5b1). The inclined portion is provided across a range of no less than 180 around the center of the spiral.