An electric pump is provided, which may include a motor unit including a rotation shaft, and a pump unit including a rotor having a vane groove accommodating a vane and coupled with the rotation shaft, and including a pump plate including an external wall portion and a cam ring having a cam surface on which the vane slides, and a bottom lid portion provided in the pump plate and being integrally formed with the external wall portion and the cam ring, and a connection unit being provided between the external wall portion and the cam ring to connect the external wall portion and the cam ring and protruding in a direction away from the bottom lid portion, and the connection unit is integrally formed with the external wall portion, the cam ring, and the bottom lid portion.

A rotary compressor is provided that may include a casing, a cylinder, a main bearing, a sub bearing, a rotational shaft, a roller, and at least one vane. The cylinder may include at least one elastic deformation unit to absorb impact with the at least one vane. With this structure, a collision force caused due to chattering of the at least one vane may be absorbed to suppress or prevent friction loss and/or wear between the cylinder and the vane, thereby enhancing compressor efficiency, reducing vibration noise, and enabling fast initial actuation.

An electric compressor includes a compression portion, an electric motor, an inverter, a housing, a support bracket, a vibration insulator, and a soundproofing cover. The compression portion is configured to compress a fluid. The electric motor is configured to drive the compression portion. The inverter is configured to drive the electric motor. The housing includes an outer peripheral surface that has a cylindrical shape and accommodates the compression portion, the electric motor, and the inverter. The support bracket is fastened to the housing and supports the housing to an object to which the electric compressor is mounted. The vibration insulator is interposed between the support bracket and the object. The soundproofing cover is made of an elastically deformable sound absorbing material and covers the housing and the support bracket.

An electric vehicle vacuum pump assembly includes a combination, a separate acoustic barrier casing configured to encase the combination in each of a radially-spaced relationship and an axially-spaced relationship, and an annular gastight attenuation assembly radially arranged between the separate acoustic barrier casing on a first side and the combination on a second side. The combination comprises a pump unit and a drive motor comprising a rotor space, a stator space, a ventilation inlet, and a ventilation outlet. The rotor space comprises a motor rotor, and the stator space comprises a motor stator. The separate acoustic barrier casing comprises an intake connection and a discharge connection. The ventilation inlet and the ventilation outlet of the drive motor are configured to provide a forced ventilation past the annular gastight attenuation assembly and through at least one of the rotor space and the stator space.

A pump device includes: a main pump and a sub pump; and a switching valve that switches so as to supply the hydraulic oil discharged from the sub pump to the hydraulic device, or to return the hydraulic oil discharged from the sub pump to the suction side. The main pump and the sub pump each include: a rotor, a discharge port into which the hydraulic oil discharged from a pump chamber is led, and a groove-shaped discharge-side notch formed from an opening edge of the discharge port toward a direction opposite to a rotation direction of the rotor. The switching valve switches according to a rotation speed of the drive shaft. At least one discharge-side notch of the sub pump is formed so that a resistance applied to the flow of the hydraulic oil passing therethrough is greater than that of the discharge-side notch of the main pump.

A vacuum pump, e.g. a rotary vane vacuum pump, generates a vacuum, in a suction device, with an air intake device and an air exhaust device, as well as a motor for driving the vacuum pump. The air exhaust device is provided with a discharge valve. The exhaust air is downstream of the discharge valve divided into two partial flows that are respectively associated with a pipe section.

According to the disclosure, a pump unit includes a vibration sensor or a noise sensor, and a controller may control a driving operation of a pump driving unit on the basis of vibration data or noise data. Furthermore, in case that pump driving units are provided, control is performed to adjust a fault threshold value in consideration of influence of vibration or noise therebetween, and thus the reliability of detection or diagnosis of a fault of a pump can be improved, and the safety of an operator can be promoted.

A vibration frequency adjustment system, comprising a vibratable component (102), at least one counterweight (401, 402), at least one drive device (407, 408), and a controller (307). The vibratable component (102) is configured to be connected to a vibration source (101). The vibration source (101) has an operating frequency range, and the vibratable component (102) has a natural vibration frequency. The at least one counterweight (401, 402) is configured to be movable along the vibratable component (102). The at least one drive device (407, 408) is configured to enable the at least one counterweight (401, 402) to be maintained at or moved to various counterweighting positions (421, 422, 423) on the vibratable component (102). The controller (307) is communicatively connected to the at least one drive device (407, 408). The vibration frequency adjustment system is used for a variable-frequency screw unit so as to reduce the vibration of an exhaust pipe.

A rotary compressor according to an embodiment includes a plurality of eccentric parts, a first balancer, and a second balancer. The plurality of eccentric parts include a first eccentric part, a second eccentric part, and a third eccentric part disposed to be aligned from one side to the other side. The second balancer is disposed on the other side of the first balancer. Angles between a direction of eccentricity of the first balancer and directions of eccentricity of the plurality of eccentric parts are configured to increase in an order of the third eccentric part, the second eccentric part, and the first eccentric part. Angles between a direction of eccentricity of the second balancer and directions of eccentricity of the plurality of eccentric parts are configured to increase in an order of the first eccentric part, the second eccentric part, and the third eccentric part.

A pneumatic motor includes a stator having a stator inner wall including a dwell region and a rotor eccentrically disposed within the stator. The rotor is configured to rotate about the axis of rotation and includes a plurality of vanes disposed around the rotor. Each vane of the plurality of vanes is configured to slide within a respective slot formed in the outer surface of the rotor between a fully retracted position and a fully extended position as the rotor rotates about the axis of rotation to maintain contact with the stator inner wall. The stator inner wall has a radius relative to the axis of rotation that is substantially constant within the dwell region so that vanes of the plurality of vanes are in the fully extended position within the dwell region.