Hydraulic valves for dampening pressure spikes and associated methods are disclosed herein. In one embodiment, a hydraulic valve for dampening pressure spikes includes: a spool configured to move axially inside the hydraulic valve; and a sleeve configured to at least partially house the spool. A location of the spool with respect to the sleeve may determine a flow of a working fluid through the hydraulic valve. A viscous damper is at least partially housed inside an opening in the spool, and a viscous friction between the viscous damper and the opening in the spool slows a motion of the spool.

Microscale valves for use in, e.g., micropump devices, may be formed of a slitted diaphragm bonded o the interior of a valve tube. A bump in the diaphragm and/or a backward-leakage stopper may increase the breakdown pressure of the valve. A push-rod may be used to pre-load the valve membrane to thereby increase the cracking pressure.

The present invention's goal is to devise an apparatus (here-forth called punch-ball) made of a tension-reversible membrane that will assume a particular three-dimensional predetermined shape when under tension, apparatus that will border a central empty space, central space limited by the interior face of the membrane, and central space that will be in direct communication with the exterior space outside of the external face of the punch-ball through orifices in the membrane (here-forth called punches), punches that will not decrease the ability of the membrane to exhibit a tension force. The punch-ball can be used freestanding or in connection with an object representing a confined space that will be abutting the exterior face of the punch-ball when the punch-ball is under tension. The punches will allow fluid to flow freely or solids to be transferred freely between the interior and exterior of the punch-ball membrane without any limitations to the initial flow through the cavity prior to the punch-ball membrane being deployed in the cavity, the interior face of the membrane being defined as surrounding the empty space inside the punch-ball while the exterior face of the membrane as facing the exterior of the punch-ball. The membrane will be provided with hinge borders (borders that will lack completely or partially the property of being under tension, and at same time have various degrees of elasticity or deformability), borders that will allow the punch ball shape to adapt to the shape of the cavity in which it will be deployed, or for the action to be undertaken. At the end of the action performed the tension in the membrane will cease, the punch-ball will be un-deployed and then removed from the location of action.

A valve body arrangement for a hydraulic or pneumatic valve comprises two elements between which a valve body is retained. The two elements are welded together in a first region, preferably by the laser transmission method, and clamp the valve body in a second region with a force.

A bypass valve (130) that regulates a flow of a fluid in a waste heat recovery system (100) is provided. The bypass valve (130) comprises a valve housing (220), an expander poppet (250) coupled to the valve housing (220) and adapted to prevent the flow of the fluid to an expander (140), and a valve stem (230) with at least a portion disposed in the valve housing (220) wherein the valve stem (230) is adapted to displace the expander poppet (250) to allow the fluid to flow to the expander (140), and regulate the flow of the fluid.

Microscale valves for use in, e.g., micropump devices, may be formed of a slitted diaphragm bonded o the interior of a valve tube. A bump in the diaphragm and/or a backward-leakage stopper may increase the breakdown pressure of the valve. A push-rod may be used to pre-load the valve membrane to thereby increase the cracking pressure.

A clack valve assembly comprising: a valve seat comprising an opening; a bearing comprising a recess with a base, a mouth, and a pair of side walls between the base and the mouth; a lid comprising a lid plate and a shaft, the shaft being received in the recess of the bearing; and a shaft retaining member which closes the mouth of the recess in the bearing, thus retaining the shaft within the recess. The shaft and the lid plate are integrally formed elements of a single part. The shaft can rotate within the recess to enable the lid to rotate from a closed position in which the lid engages the valve seat and covers the opening, to an open position in which the lid lifts away from the valve seat enabling fluid to flow through the opening in the valve seat.