A self-priming assembly for a multi-stage pump is provided. The self-priming assembly can have a first diffuser, a second diffuser, and an impeller. The first and second diffusers each include a central portion, a diffuser axis, an arcuate channel within the central portion, and a passage extending through the central portion. The first diffuser and the second diffuser are configured to be combined and receive the impeller therebetween with the first diffuser axis, the second diffuser axis, and the impeller axis aligned.

An impeller for a fluid pump includes a hub having an outer surface; an outer ring which is concentric with the hub and having an inner surface; and a plurality of blades extending from a root at the outer surface to a tip at the inner surface. Each of the blades has a first leg and a second leg which meet at a vertex such that a concave side of the blades faces toward a rotational direction and such that a convex side of the blades faces away from the rotational direction. The concave side of each one of the plurality of blades forms a draft angle with the convex side of another one of the plurality of blades which is immediately adjacent thereto in the rotational direction. The draft angle at the inner surface is less than or equal to 10% of the draft angle at the outer surface.

In accordance with at least one aspect of this disclosure, embodiments of fluid pumps, pump cases, valve bodies, and volutes are disclosed herein. Embodiments of methods for manufacturing fluid pumps, pump cases, valve bodies, and volutes are also disclosed herein. Embodiments can include additive manufacturing, for example. Certain embodiments can include additively manufacturing a pump case in a tilted orientation, utilizing only coincidental support structure having a unique shape, and with teardrop shaped volute and/or valve body.

In accordance with at least one aspect of this disclosure, embodiments of fluid pumps, pump cases, valve bodies, and volutes are disclosed herein. Embodiments of methods for manufacturing fluid pumps, pump cases, valve bodies, and volutes are also disclosed herein. Embodiments can include additive manufacturing, for example. Certain embodiments can include additively manufacturing a pump case in a tilted orientation, utilizing only coincidental support structure having a unique shape, and with teardrop shaped volute and/or valve body.

A fuel pump system has a start stage pump and a main stage pump. Fuel is supplied to the start stage pump at lower engine speeds. As the engine speed increases, the fuel system restricts fuel to the start stage pump via a pressure regulating valve and the main stage pump takes over. An electronically controlled shut-off valve limits the amount of fuel supplied to the pressure regulating valve and, hence, the start stage pump when closed to safeguard against operating the start stage pump at unsafe engine speeds.

A fuel system, including a first pump, a second pump and a filter module. The filter module has a housing defining an interior, a filter received in the interior, a filter inlet through which fluid flows into the interior, a filter outlet from which fluid flows out of the interior, and a vent body received within the interior. The vent body has a passage and a vent orifice. The filter is arranged so that fluid that enters the filter inlet flows through the filter before flowing out of the filter outlet and the interior includes an upper portion arranged above a lower portion relative to the force of gravity, and the passage communicates with the filter outlet and with the lower portion of the interior and the vent orifice communicates with the passage and with the upper portion of the interior.

The application discloses a multipurpose transfer pump free of secondary water filling, which comprises a cover plate, a water filling plug, a pump body, an impeller, a pump body flange and a motor, the pump body flange is provided at an end portion of the motor, the pump body is provided on a front surface of the pump body flange, a volute chamber corresponding to the impeller is provided in a back surface of the pump body in an inwards recessed manner. In this way, the multipurpose transfer pump free of secondary water filling disclosed by the application can achieve a self-priming effect without filling water into the pump body when the motor works for a second time, thus improving the impeller lubricating effect.

A levering device includes a coupling block, a gripper, an operating rod, and a constraint sleeve. The coupling block includes a coupling chamber, two guide slots in communication with the coupling chamber, an extension rod, and an axial hole axially cut through the extension rod in communication with the coupling chamber. The operating rod being axially movably inserted through the axial hole into a bearing chamber of a housing of a motor-driven water lifting device to stop against respective one end of a wheel axle of the motor-driven water lifting device. The gripper is attachable to the two guide slots of the coupling block and includes two gripper blocks and two claw bars respectively connected to the gripper blocks. The constraint sleeve is sleeved onto the coupling block to stop the two claw bars in the respective the guide slots.

A motor vehicle fuel pump cover system. The system protects a connection between a fuel line and a fuel pump. The cover includes a cover for a fuel pump. Both parts of the cover define a raised wall around the connection. The cover also includes a second cover. The second cover is hinged to the first cover and forms a dome to cover the connection. The dome has an interior peripheral surface that covers the raised wall to thereby form a chamber protected against foreign matter infiltration. In another aspect, the disclosure relates to a motor vehicle fuel pump having an exterior fuel connection protected by the cover system against damage caused by foreign matter.

A multi-way coolant valve and a heat pump system having the same include an external housing in which first, second and third external inlets and first, second and third external outlets are formed; and an internal housing provided rotatably inside the external housing to selectively fluidically-connect the first, second and third external inlets, and the first, second and third external outlets, and divided into two stages through which a coolant flows respectively, wherein as the internal housing rotates at a predetermined interval in a selected mode of the vehicle, the first external inlet selectively fluidically-communicates with the first external outlet, the second external outlet, or the third external outlet, the second external inlet selectively fluidically-communicates with the first external outlet or the second external outlet, and the third external inlet selectively fluidically-communicates with the first external outlet, the second external outlet, or the third external outlet.