Abstract: A mechanical shutdown valve for preventing an over pressure condition is described. A valve body has an inlet, an outlet, and a channel extending from the inlet to the outlet. A valve seat and a diaphragm are positioned in the valve body. The diaphragm controls a fluid flow through the valve body. A mesh is coupled to the diaphragm such that the mesh and the diaphragm separate an upstream portion of the channel from a downstream portion of the channel. The mesh extends from the diaphragm to an inner surface of the valve body and limits fluid flow between the diaphragm and the valve body. A spring biases the diaphragm towards the open position. A characteristic of the spring determines a differential pressure threshold between the upstream portion of the channel and a downstream portion of the channel at which the diaphragm engages the valve seat.

Abstract: A sanitary insertion unit (1), including an insertion housing (6), in which insertion housing a valve having a valve piston (10) is provided, which valve piston is slidably guided in the insertion housing and can be moved from a resting position under the pressure of the inflowing water against the restoring force of at least one restoring element (11). The restoring unit has at least one movement damper (12, 13), which damps or brakes the movement of the valve piston from the resting position to the open position.

Abstract: A damping valve includes a damping valve body having at least one throughflow orifice which is at least partially covered by at least one valve disk by the action of a closing force. At least one spring body exerts an opening force on the valve disk that is less than the closing force. The at least one spring body is constructed as an elastomeric body separately from the control edge.

Abstract: A valve system includes: a valve; a hydraulic cylinder attached to at least a portion of the valve; and at least a first accumulator in fluid communication with the hydraulic cylinder. The first accumulator includes: (i) a first end having a fluid inlet and a fluid outlet; (ii) a second end having a gas inlet; and (iii) a body positioned between the first end and the second end and which includes a fluid chamber and a gas chamber separated by a flexible separating member. The hydraulic cylinder is configured to close the valve in response to pressure provided by fluid distributed from the first accumulator.

Abstract: A check valve for a fluid system includes: a valve body defining an inlet, an outlet, and an interior cavity; a closing member positioned inside the interior cavity, the closing member movable between an open position, providing fluid communication between the inlet and outlet, and a closed position, isolating the inlet from the outlet; and a buffer mounted on the valve body, the buffer configured to hold a portion of fluid in the fluid system and cushion movement of the closing member from the open position to the closed position.

Abstract: A device in accordance to an embodiment includes a tubular housing having an inside diameter defining an axial bore, a top surface and an outer surface, a groove formed along the outer surface below the top surface, a flapper pivotally connected with the housing and pivotal between an open position to allow flow through the bore and a closed position to block flow through the bore and a torsion spring having a spring diameter and disposed in the groove and in connection with the flapper to bias the flapper to one of the open and the closed position. The torsion spring may be nested in a C-shaped groove.

Abstract: The invention relates to a pressure regulator for a high-pressure ramp of a system for injecting fuel into an internal combustion engine, comprising a solenoid valve element (10) which receives an electromagnet (40). The electromagnet controls a needle (20) that closes a valve seat (30) which is connected to a high-pressure inlet and opens into a discharge chamber (13), said discharge chamber communicating with a liquid recirculation system (5) by means of outlet openings (14). The rear face (12) of the solenoid valve element (10) receives a coil (40) which controls the opening process of an armature (41) that is rigidly connected to the needle (20) and is subject to a closing return spring (25). The discharge chamber (13) is located on the front face (11) of the solenoid valve element (10) on the axis (XX) of the needle (20), and the discharge chamber surrounds the needle.

Abstract: A pressure control valve capable of preventing or suppressing the occurrence of the flaw that a pilot valve element which receives hydraulic pressure from a hydraulic fluid vibrates and hits a pilot valve seat member producing strange noise when the pilot valve element is in an opening state without resulting in an increase in number of components and assembling man-hours, the pressure control valve is provided with a main valve part containing a main valve element and a valve housing that includes a main valve seat on which the main valve element is able to be seated and a pilot chamber in which the main valve element is put in a slidable manner, and a pilot valve part containing a pilot valve element and a pilot valve seat member that includes a pilot valve seat on which the pilot valve element is able to be seated, the pilot valve element moving apart from the pilot valve seat to open when pressure in the pilot chamber exceeds a predetermined pressure.

Abstract: The present invention relates to a damping valve for a shock absorber, comprising a base body with a first support body and with a second support body and comprising one or more valve spring discs which separate a first damping fluid space from a second damping fluid space, wherein the valve spring discs are supported against the first support body via an inner edge support, and against the second support body via an outer edge support, and which control a passage of damping fluid in both directions by virtue of the fact that the valve spring discs lift-off either from the inner edge support or from the outer edge support, by elastic deflection. According to the invention, a stroke movable control body is provided which is prestressed against the valve spring discs, so that the control behaviour of the valve spring discs can be adjusted via the edge supports by the prestress of the control body.

Abstract: The invention concerns an outlet valve, in particular of a vacuum pump, with a main valve spring which, in a closed state of the outlet valve, closes at least one outlet opening from which the main valve spring lifts off on opening of the outlet valve, and with a hold-down element which forms a stop for the main valve spring on opening, wherein at least one additional valve spring is arranged between the main valve spring and the hold-down element. The invention is distinguished in that in closed state of the outlet valve, the additional valve spring is partly spaced from the main valve spring in the opening direction, in particular spaced with a free end from a free end of the main valve spring.

Abstract: Embodiments of the present invention generally include a pressure relief system and methods of use, in which an apparatus includes an upper chamber fluidly connected to a pressurized fluid source, a lower chamber having an inlet and an outlet, a vertically moveable plate intermediate the chambers and disposed within a plate support, and connected to the plate by a vertical shaft, a vertically actuating lower chamber inlet valve including an inlet seal. Pressure relief is accomplished by controlling fluid pressure in the upper chamber such that varying downward force on the plate and therefore, via the shaft, the inlet seal, allows for selective opening/closing of the inlet valve as a function of upper chamber fluid pressure relative to the pressure exerted from a fluid source for which pressure relief is desired, beneath the inlet seal, whereby over-pressured fluid entering the lower chamber via the inlet is vented out the outlet.

Abstract: Provided is a check valve element enabling efficient supply of fluid while suppressing the occurrence of chattering. The check valve element is provided to be displaceable upstream and downstream in a downstream flow path extending downstream from a valve seat having an opening for introducing a fluid and is pressed against the valve seat by a pre-closing urging force applied thereto toward an upstream side.

Abstract: An emergency shut-off valve includes a valve body defining an inlet, an outlet, a valve port between the inlet and the outlet, and an aperture. A valve assembly is positioned partially within the valve body and extends through the aperture. An actuator assembly is operatively coupled to the valve assembly to move the valve assembly between an open position and a closed position and includes a poppet and a rotatable shaft. The poppet is disposed within the valve body and is moveable between an open position that allows the flow of fluid through the valve body and a closed position that prevents the flow of fluid through the valve body. The shaft is coupled to the poppet and has a retaining member positioned within a slot in an arm of the poppet to prevent the poppet from being removed from the shaft.

Abstract: A pressure relief valve includes a valve body having an inlet and an outlet and defining a first fluid path fluidly connecting the inlet and the outlet of the valve; a valve member axially moveable between a first position and a second position, the valve member configured to close the fluid path in the first position and thereby restrict flow between the inlet and the outlet, the valve member configured to open the fluid path in the second position and thereby allow flow between the inlet and the outlet; a biasing element configured to bias the valve member in the first position; and a friction element resiliently biased laterally against an axially extending surface of the valve member to provide frictional resistance to movement of the valve member and thereby cause hysteresis in axial movement of the valve member between the first position and the second position.

Abstract: An expansion valve includes a shaft for transmitting the drive force to a valve element and a vibration-proof spring, set between the body and the shaft, which generates the sliding friction by biasing the shaft. The vibration-proof spring includes a spring body of a hollow tube shape, a spring part, which is integrally formed with a side wall of the spring body, and a bulging portion formed on the spring part in a protruding manner such that the tip of the bulging portion is placed opposite to a part of the shaft. When the bulging portion abuts against the shaft inserted to the vibration-proof spring, the spring part is placed in a position along the spring body or is warped outwardly from the spring body, so that the elastically reactive force resulting from the warped spring part allows the shaft to slide in a stabilized manner.

Abstract: A compressor has suction reed valves each of which includes a fixation portion fixed to the valve base plate, a basal portion that extends from the fixation portion and is separable from the plate, and a valve flap extending from the basal portion toward the distal end to selectively open and close the suction port. Each suction port has a shape elongated in the width direction, which is orthogonal to the longitudinal direction. The width of the basal portion is greater than that of the suction port. Each valve flap includes an opening-closing portion facing the corresponding suction port and stoppers, which project from the ends in the width direction. The side edges in the width direction are continuous from the stoppers to the basal portion to gradually approach the suction port. The cylinder block has pairs of recessed retainers. The stoppers contact the retainers.

Abstract: The scroll refrigeration compressor according to the invention includes a sealed enclosure at least partially defining a discharge chamber designed to be connected to a discharge line, and a discharge valve attached on the sealed enclosure and fluidly connected to the discharge chamber. The discharge valve includes a valve body, a valve seat, and a discharge check valve movable between a covering position and a released position. The discharge valve includes deflection means positioned in the valve body and arranged to orient the flow of refrigerant coming from the discharge line at least partially toward the periphery of the discharge check valve.

Abstract: An apparatus for mixing a first fluid into a flow path (44) of a second fluid, said apparatus having a chamber (12), which encloses the flow path and exhibits a first inlet (13) for receiving the second fluid, a second inlet (15) arranged downstream of the first inlet for receiving the first fluid, as well as an outlet arranged downstream of the second inlet for discharging a mixture of the first fluid and the second fluid, said flow path extending from the first inlet to the outlet and said second inlet opening into the flow path, a throttle body (29), which is pivotally arranged inside the chamber for controlling the flow area of the flow path, and pivoting means (50, 51) for pivoting the throttle body for said controlling of the flow area.

Abstract: Valves, and particularly check valves, are detailed. The valves may isolate a spring or other biasing member from flowing fluid so as to reduce the possibility of damage to the spring caused, for example, by chemicals contained in the fluid. In some versions of the valves, the spring may be positioned within a cavity of a cover sealed from the fluid.

Abstract: The invention relates to a fuel overflow valve for a fuel injection system, particularly for limiting the pressure in a low-pressure region of the fuel injection system. The fuel overflow valve has a valve housing, in which a valve member is disposed in a stroke-moving manner, the stroke movement of the valve member controlling a connection of an inlet to the valve housing to a release region. The valve member is loaded by a valve spring in the direction of a locking position in which the connection of the inlet to the release region is interrupted, and is loaded by the pressure present in the inlet in the opening direction. The valve member may carry out a further stroke in the locking direction beyond the locking position thereof, where the valve spring does not act upon the valve member.

Abstract: Tunable check valves reduce valve-generated vibration to increase the reliability of tunable fluid ends. Selected improved designs described herein reflect disparate applications of identical technical principles (relating to, e.g., the vibration spectrum of an impulse). Tunable check valve embodiments comprise a family including, but not limited to, tunable check valve assemblies, tunable valve seats, and tunable radial arrays. Each such tunable embodiment, in turn, contributes to blocking excitation of fluid end resonances, thus reducing the likelihood of fluid end failures associated with fatigue cracking and/or corrosion fatigue. By down-shifting the frequency domain of each valve-closing impulse shock, initial excitation of fluid end resonances is minimized.

Abstract: Tunable fluid ends reduce valve-generated vibration to increase fluid-end reliability. Tunable fluid end embodiments comprise a family, each family member comprising a fluid end housing with at least one installed tunable component chosen from: tunable check valve assemblies, tunable valve seats, tunable radial arrays and/or tunable plunger seals. Each tunable component, in turn, contributes to blocking excitation of fluid end resonances, thus reducing the likelihood of fluid end failures associated with fatigue cracking and/or corrosion fatigue. By down-shifting the frequency domain of each valve-closing impulse shock, initial excitation of fluid end resonances is minimized. Subsequent damping and/or selective attenuation of vibration likely to excite one or more predetermined (and frequently localized) fluid end resonances represents further optimal use of fluid end vibration-control resources.

Abstract: Tunable fluid ends reduce valve-generated vibration to increase fluid-end reliability. Tunable fluid end embodiments comprise a family, each family member comprising a fluid-end housing with at least one installed tunable component chosen from: tunable check valve assemblies, tunable valve seats, tunable radial arrays and/or tunable plunger seals. Each tunable component, in turn, contributes to blocking excitation of fluid end resonances, thus reducing the likelihood of fluid end failures associated with fatigue cracking and/or corrosion fatigue. By down-shifting the frequency domain of each valve-closing impulse shock, initial excitation of fluid end resonances is minimized. Subsequent damping and/or selective attenuation of vibration likely to excite one or more predetermined (and frequently localized) fluid end resonances represents further optimal use of fluid end vibration-control resources.

Abstract: A pressure control valve including a valve housing having a first opening and second opening. The valve housing including a valve member configured to control gas flow between the first opening and the second opening. The valve member is supported by a first membrane and a second membrane, both of which are formed on a single-piece membrane body.

Abstract: A water-hammer proof and silent check valve comprises a shell (1), a spring (9), a flow guide body (10) and a cowl (11). The flow guide body (10) is provided with flow blocking boards (4, 6) which project from the outer surface of the flow guide body (10) and are capable of rotating around installation shafts (3, 7). A plurality of flow blocking boards are arranged in the flow passage in the axial direction of the valve, so that most part of pressure energy and kinetic energy are undertaken by the flow blocking boards by grading when liquid flows back to the valve, thus ensuring that the water hammer with large energy is divided into multiple water hammers with relatively smaller energy so as to greatly reduce the inner stress of valve bearing parts.

Abstract: A valve member having a valve part and a piston part is accommodated in a piston accommodation cylinder part of a case reciprocatably, and a damper chamber that is substantially a sealed space is formed in an anti-valve seat side in the valve member so that fluid flows without flowing via the damper chamber. Accordingly, since the fluid does not pass through the damper chamber, a fluid force that occurs in the piston part due to a fluid flow does not change easily, thus it becomes difficult to increase hunting at the valve members. Moreover, in a vibrational component in the valve member reciprocating direction of the valve members, amplitude of the vibration can be decreased by a damping force generated in the damper chamber.

Abstract: A check valve for deterring intrusion into drain pipes comprises a body member having at least a first orifice and configured to mount on a drain pipe wherein the drain pipe is adapted to promote fluid flow in a single direction. Pivotably mounted on said body member will be a valve member. The mounting arrangement will provide a closed position that substantially occludes the first orifice and a range of open positions when the valve member is pivoted to open in the flow direction. In addition, at least one additional orifice is provided in either the body member or the valve member to permit fluid flow irrespective of the position of the valve member.

Abstract: A valve is provided. The valve includes a flapper member. A barrel is coupled to the flapper member, the barrel having an interior volume and at least one movable vane within the interior volume. A shaft member is rotationally coupled to the barrel, the barrel having at least one stationary vane disposed within the interior volume.

Abstract: A pipe break valve device includes a housing that has a recess continuous in a flow direction, a valve slide that is arranged displaceably in the flow direction in the recess, and a spatial volume of a throttle device that is arranged at least in regions between the outer wall of the valve slide and the inner wall of the housing. Throttle ducts that are present on the inlet side and on the outlet side are formed by a first gap and a second gap which are present in each case between the outer wall of the valve slide and the inner wall of the housing, and no sealing means are present between the inner wall of the housing and the outer wail of the valve slide.

Abstract: A pneumatic pressure regulating valve, the opening of which can be automatically changed in a pressure-related manner, including a control diaphragm that is subjected to a reference pressure, to the gas pressure as well as to a governor spring, wherein a change in the differential pressure causes an adjustment of the control diaphragm and the latter itself or a closing element actuated by it changes the opening through an outflow cross-section, and wherein a structure that is arranged adjacent to the outflow cross-section on the diaphragm side forms a stop for the control diaphragm or for the closing element in the closed position of said control diaphragm.

Abstract: An apparatus for controlling flow of a fluid includes a closure member, a biasing member applying a biasing force to the closure member, and a sealing member receiving the closure member. A dampener is operatively connected to the closure member and may resist a force applied to the closure member. A fluid seal may be formed when the biasing member presses the closure member against the sealing member. The apparatus may include a wellbore tubular in which the fluid conduit is formed and the closure member and sealing member may cooperate to control fluid flow along the fluid conduit. The apparatus may include an actuator configured to control the force applied to the closure member. The actuator may adjust the biasing force, and/or the dampening force. Also, a controller may control the actuator and may be responsive to a signal generated at a surface location, a signal generated at a downhole location, and/or a signal generated by a sensor.

Abstract: A compressor plate valve having a valve seat, a valve guard and a valve plate. The valve plate is moveable between the valve guard and valve seat to control fluid passage through passages in the seat, the guard, and the plate. A valve stem passes through the center of the valve guard and is attached to the center of the valve plate. The valve stem provides guidance for the plate valve to ensure parallel motion. In addition to sealing surfaces that oppose passages, the seat and plate have landing surfaces that provide a braking effect when the valve closes through squeeze film action.

Abstract: An apparatus for facilitating the removal of moisture from a compressed air tank has a tank with an interior volume, a tubular member positioned in communication with the tank and having an end adjacent the bottom of the tank, an air compressor interconnected to the tubular member for passing compressed air into the interior volume of the tank, a check valve positioned at an opposite end of the tubular member, a head pressure relief valve in communication with the tubular member, and a pressure switch cooperatively connected to the air compressor. The pressure switch opens the head pressure relief valve when an air pressure in the tank reaches a desired level so as to cause air and water in the tank to pass through the tubular member. The check valve serves to stop the passing of air and water after a period of time.

Abstract: A pneumatic pressure regulating valve, the opening of which can be automatically changed in a pressure-related manner, including a control diaphragm that is subjected to a reference pressure, to the gas pressure as well as to a governor spring, wherein a change in the differential pressure causes an adjustment of the control diaphragm and the latter itself or a closing element actuated by it changes the opening through an outflow cross-section, and wherein a structure that is arranged adjacent to the outflow cross-section on the diaphragm side forms a stop for the control diaphragm or for the closing element in the closed position of said control diaphragm.

Abstract: A water-hammer proof and silent check valve comprises a shell (1), a spring (9), a flow guide body (10) and a cowl (11). The flow guide body (10) is provided with flow blocking boards (4, 6) which project from the outer surface of the flow guide body (10) and are capable of rotating around installation shafts (3, 7). A plurality of flow blocking boards are arranged in the flow passage in the axial direction of the valve, so that most part of pressure energy and kinetic energy are undertaken by the flow blocking boards by grading when liquid flows back to the valve, thus ensuring that the water hammer with large energy is divided into multiple water hammers with relatively smaller energy so as to greatly reduce the inner stress of valve bearing parts.

Abstract: A slide-type pressure control valve having an improved damping behavior is described.

Abstract: A vacuum brake booster includes a housing and a bent connecting element for connecting the vacuum brake booster to a vacuum source, wherein the connecting element includes a first connecting piece which extends through an opening in the brake booster housing into a vacuum chamber of the vacuum brake booster, a second connecting piece for connecting the connecting element to the vacuum source, and a multi-part housing with a first housing part which carries the first connecting piece and a second housing part which carries the second connecting piece arranged at a first angle to the first connecting piece.

Abstract: A pneumatic pressure regulating valve, the opening of which can be automatically changed in a pressure-related manner, including a control diaphragm that is subjected to a reference pressure, to the gas pressure as well as to a governor spring, wherein a change in the differential pressure causes an adjustment of the control diaphragm and the latter itself or a closing element actuated by it changes the opening through an outflow cross-section, and wherein a structure that is arranged adjacent to the outflow cross-section on the diaphragm side forms a stop for the control diaphragm or for the closing element in the closed position of said control diaphragm.

Abstract: An adjustable pressure relief valve for use in hydraulic circuits, particularly for controlling pressure transients—acceleration and deceleration—of hydraulic motors subject to inertia forces (progressive anti-shock pressure relief valves) is characterized by reduced leakage, involving a reduced influence of flow forces during valve control, as well as reduced pressure losses; these characteristics prevent the hydraulic motor from rotating when it is subject to a drive load and is not powered, eliminate vibrations and instability of valve-regulated pressure, especially at low flow rates, and ensure an adjustment value varying according to the flow rate through the valve. A further characteristic of the valve is the reduced number of its components, resulting in greater cost effectiveness.

Abstract: A steel dampening ring rests on a wafer spring in an annular groove in a compressor valve stop plate to dampen the action of the plastic valve plate to prolong the life of the valve.

Abstract: A vacuum relief safety valve includes a housing defining an inner chamber and attached to the suction-side of the swimming pool or spa pump. An air inlet aperture is formed in the housing so as to be open to ambient air. A sealing element is disposed within the housing and biased against the air inlet aperture by a spring so as to effectively seal the inner chamber of the housing from ambient air. When a maximum allowed vacuum level within the pump is exceeded, such as when a swimming pool drain is obstructed, the sealing element moves into the inner chamber and opens the air inlet aperture causing the pump to rapidly lose its prime and enabling removal of the entrapment.

Abstract: A vacuum relief safety valve includes a housing defining an inner chamber and attached to the suction-side of the swimming pool or spa pump. An air inlet aperture is formed in the housing so as to be open to ambient air. A sealing element is disposed within the housing and biased against the air inlet aperture by a spring so as to effectively seal the inner chamber of the housing from ambient air. When a maximum allowed vacuum level within the pump is exceeded, such as when a swimming pool drain is obstructed, the sealing element moves into the inner chamber and opens the air inlet aperture causing the pump to rapidly lose its prime and enabling removal of the entrapment.

Abstract: A mesovalve having a diaphragm situated between a first chamber and a second chamber. There may be an inlet and an outlet in the first chamber. The diaphragm may provide an orifice between the first and second chambers. There may be a first electrode on the diaphragm and a second electrode on an inside surface of the second chamber. The diaphragm may have first and second positions, or numerous variable positions. Applying a voltage across the electrodes may electrostatically move the diaphragm to the second position during which the outlet is at least partially opened for fluid communication with the inlet, the orifice is closed and the diaphragm is stopped in the second position by a cushioning fluid pressure in the second cavity to prevent pull-in. Removing the voltage from the electrodes may let the diaphragm return to the first position, open the orifice and close the outlet.

Abstract: A damping system, for a valve with a flapper movable between an open position and a closed position, comprises a main body and a piston. The main body has at least an inner wall that defines a chamber having fluid therein. The main body is coupled to the flapper, and is configured to move therewith. The piston is disposed at least partially within the chamber. The piston is configured to move within the chamber in a direction opposite the direction of movement of the main body when the flapper approaches the open position or the closed position, to thereby compress the fluid in a section of the chamber and slow movement of the main body. Movement of the flapper is thereby slowed when approaching the open position or the closed position.

Abstract: A reed valve assembly is provided with a body, at least one flexible member, and at least one rigid member. Preferably, the at least one flexible member has a periphery so as to substantially cover opening(s) in the body when positioned adjacent to the body, and the at least one rigid member has a periphery so as to limit deformation of the at least one flexible member.

Abstract: A mechanized vent for a dishwasher employs a vent plate moving about a hinge axis as driven by a cam mechanism at a surface of the vent plate removed from the hinge axis.

Abstract: A damping system, for a valve with a flapper movable between an open position and a closed position, comprises a main body and a piston. The main body has at least an inner wall that defines a chamber having fluid therein. The main body is coupled to the flapper, and is configured to move therewith. The piston is disposed at least partially within the chamber. The piston is configured to move within the chamber in a direction opposite the direction of movement of the main body when the flapper approaches the open position or the closed position, to thereby compress the fluid in a section of the chamber and slow movement of the main body. Movement of the flapper is thereby slowed when approaching the open position or the closed position.

Abstract: A damping system for a valve with a flapper comprises a main body having at least an inner wall defining a chamber having fluid therein, a paddle disposed within the chamber, and a fluid channel. The paddle is coupled to the flapper and moved thereby between a first and second position when the flapper is in a closed and an open position, respectively, and is configured to force fluid from at least a section of the chamber when approaching the first or second position. The fluid channel is coupled to the chamber section, and is configured to allow fluid egress out of the chamber section at a first egress rate when the paddle moves from the first position to a predetermined intermediate position between the first and second positions, and at a second, lower egress rate when the paddle moves from the predetermined intermediate position to the second position.

Abstract: An electromagnetic controlled fuel injection apparatus has a poppet valve which controls the beginning and end of fuel injection by reciprocation. Inertia force and friction force arising from the reciprocating motion of the poppet valve are utilized effectively to suppress bounce of the poppet valve. The poppet valve has a sealed inside space, and a plurality of mass objects are received in the inside space so that the mass objects can move axially while contacting with each other in the inside space due to the inertia force generated by the reciprocating motion of the poppet valve.

Abstract: A pump assembly for a penile implant is provided having a mechanism which prevents spontaneous inflation of the cylinders implanted within the user. The preventative mechanism uses overpressure generated by the reservoir during unintentional compression to effectively seal the pump assembly from unintended fluid flow. The prevention mechanism itself creates all necessary forces to prevent the undesired fluid flow to the cylinders. This is accomplished by incorporating appropriate mechanisms within the pump itself.