Abstract: A piston of an air compressor contains at least one fixing bolt configured to fix a plane of a top of a head of the piston to at least one air stop sheet. A respective one of the at least one air stop sheet includes at least one bending section and at least one acting zone surrounding the at least one bending section and configured to cover at least one air orifice. A back surface of the at least one acting zone of the respective one air stop sheet moves away from the plane of the top of the head at an open angle ?, thus producing an air flowing space. A pressure of a cylinder balances with atmosphere, and the piston is not stopped by a back-pressure resistance to move smoothly in upward and downward moving strokes after the air stop sheet moves again.

Abstract: A compressor (10), in particular a compressor for compressing a coolant, including one or more pistons (12), a cylinder block (16), and a compressor housing which at least partially houses the compressor (10), the piston(s) (12) being arranged in corresponding cylinder bores or cylinders (14) arranged at least partially in the cylinder block (16) and/or in the compressor housing so that they can move back and forth. The compressor (10) also includes an impedance tube (36) and an outlet (30) for releasing the coolant from the compressor, (10) in particular an outlet flange (32).

Abstract: A drainage device includes a closed chamber, a liquid pumping mechanism, and a liquid discharge mechanism. The drainage device can also include a controller. The closed chamber may be filled with liquid and gas for discharge. The liquid pumping mechanism pumps the liquid in the closed chamber, and prevents the liquid in the liquid pumping mechanism from flowing back to the closed chamber. The liquid discharge mechanism discharges the liquid in the liquid pumping mechanism to the outside, and prevents outside air from flowing into the closed chamber.

Abstract: A fluid transfer assembly includes a housing within which at least a portion of a pump element can be disposed. The housing includes a first surface and a second surface and defines a cavity therethrough. The housing is configured to be coupled to a reservoir such that the first surface is disposed within an interior volume of the reservoir and the second surface is disposed outside the interior volume of the reservoir. The housing includes a seal portion configured to fluidically isolate the first surface from the second surface. The cavity is configured to receive at least a portion of the pump element such that movement of the pump element produces a fluid flow from an inlet opening defined by the first surface and an outlet opening defined by the second surface.

Abstract: A piston of the type comprising a tubular skirt portion which is closed, next to an end edge, by a head portion, the skirt portion being defined by a respective tube extension and presenting an end edge region configured to affix a head portion formed in a separate piece and having a peripheral contour internal to an axial projection of the outer contour of the skirt portion.

Abstract: The present invention describes a pumping device (1) for pumping fluids. The pumping device (1) comprises a force transmitting element (2), a tension unit (3) coupled to the force transmitting element (2) and a seal element (10). The force transmitting element (2) is adapted for transferring an upstroke and a downstroke to a pump plunger (5) for pumping fluid (12). The tension unit (3) is adapted for applying a tension force (F) to the force transmitting element (2) for keeping the force transmitting element (2) under tension during the upstroke and the downstroke. The seal element (10) is adapted for sealingly preventing pumping fluids (12) during the downstroke and for enabling pumping fluid (12) during the upstroke. A part (16) of the seal element (10) is rigidly coupled with the force transmitting element (2).

Abstract: A pump assembly in the context of a piston pump having a piston carrying a disk which extends radially outwardly to engage a wall of a chamber to substantially prevent fluid flow in one direction and yet permit deflection of the disk away from the wall of the chamber to permit flow in the other direction; the improvement in which two or more of similar such disks are provided spaced axially adjacent one another.

Abstract: A piston pump includes a pump mechanism configured to compress fluid sucked from an inlet port by increasing or decreasing a volume of a pump chamber which faces a front end of a piston by reciprocating the piston housed in a housing, a feed mechanism including a feed ring mounted to an annular groove provided at an outer periphery of the piston and following a motion of the piston, a feed chamber formed between the feed ring and the housing, and a valve portion. The piston pump includes a pressure wall provided at the piston and configured to contact the feed ring to axially move the feed ring, and a restriction portion provided at the feed ring and configured to engage with an outer periphery of the piston at a position approximate to the pressure wall for restricting a radial displacement of the feed ring on the piston.

Abstract: Downhole pumps for producing hydrocarbons and/or other fluids from a well bore include a barrel having a plunger or plunger valve disposed therein and a stationary valve engaged with the barrel. The valve(s) include(s) an outer housing and an inner piston movable within the outer housing. Responsive to movement of the plunger or plunger valve relative to the barrel, the inner piston(s) is(are) movable between a first position that permits fluid flow through the valve and a second position that prevents fluid flow therethrough.

Abstract: A valve seat for use in a high pressure pump comprises an inner portion force fit within an outer portion. The outer portion has a fluid plenum at an outer peripheral surface. Fluid passages extend radially inwardly to communicate with a valve recess in the inner portion. A seal housing for a high pressure pump comprises an outer portion and an inner portion. The inner portion is force fit within the outer portion. The inner portion has an inner bore having a first location to receive seal packings, and a second location to receive valve spring structure. The inner portion has a curved surface that bottoms out against a curved surface within the outer portion.

Abstract: A pump, especially a power-steering pump, having a flow-control valve device that has a piston arranged inside a piston bore so as to be displaced. The piston bore has at least one inlet and at least one outlet channel. The piston has an axial inlet opening and a plurality of substantially radial outlet openings as well as a continuous outlet groove between a first collar and a second collar, representing a control edge for an outlet fluid flow. The axial inlet opening extends at least to the beginning of the radial, lateral outlet openings in a substantially cylindrical manner and the continuous outlet groove widens in terms of its radial depth on the outer circumference of the piston towards the control edge.

Abstract: The invention relates to an air extractor pump for waterbeds comprising a piston (1) held with longitudinal slideability in a cylinder (4), wherein the piston (1) and the cylinder (4) each are equipped at their back ends as seen in insertion direction (3?) with a valve flap (9, 17) closeably covering a through-bore (33) each, wherein the front end of the piston (1) as seen in insertion direction (3?) is equipped with a discharge bore (5), and wherein at the back end of the cylinder (4) as seen in insertion direction (3?), a thread (32) is provided wherewith it can be screwed onto a correlated screw neck (12) of a filler neck (10) of a waterbed, wherein the valve flaps (9, 17) are attached in the area of separately constructed valve cases (15, 16), wherein the piston-side valve case (16), as well as the cylinder-side valve case (15) are each equipped with a plug-in piece (19, 24) engaging with the plug-in receptacles (29, 30) of the piston (1) or the cylinder (4), respectively, in a correlated, sealed snap-in

Abstract: A pumping/compressing apparatus for use in a fluid handling system transferring a fluid from one location, e.g., a tank, to another location or to an end use is provided. The apparatus basically includes a motor and a multistage, e.g., two stage, device including at least one reciprocating piston, an inlet stage chamber, an outlet stage chamber, an inlet, and an outlet. The piston is arranged to be reciprocated at multiple, e.g., respective first and second, speeds. The second speed is higher than the first speed, whereupon when the piston is reciprocated at the first speed the device effectively pumps liquid or mostly liquid to the outlet. When the piston is reciprocated at the second speed the device effectively compresses gas or mostly gas fluid and provides it to the outlet. A blowby port may be provided to provide blowby fluid back to the tank or the device.

Abstract: A dual-direction pump includes two cylinders arranged on opposite sides of a head portion and an inlet return-flow prevention device and a leakproof device mounted between the cylinder and the head portion for avoiding leakage at the juncture between the cylinder and the head portion or leakage induced by reverse flow in one of the cylinders in the case of a single-sided pumping operation in the other cylinder. The head portion has an outlet port to which an outlet return-flow prevention device is mounted. A knob is rotatably mounted to the outlet pot and a nut is fixed to the knob for selectively engaging an inflation valve to avert detachment. The outlet return-flow prevention device prevents reverse or return flow induced in the outlet port in order to reduce resistance caused thereby and enhances pumping efficiency.

Abstract: A pump having a compressed-air-operated reciprocating motor for reciprocating a pump plunger through forward and return strokes. The motor comprises a motor cylinder and a motor piston operable in the cylinder and itself acting as a valve for effecting its return through each return stroke. A fluid dispenser is driven by the plunger between a charge position for charging a dispensing chamber with fluid and a discharge position for discharging fluid.

Abstract: A lantern and fuel system with a pump subassembly. The pump subassembly includes a beveled seat having an interior end with a cylindrical configuration constituting an interior guard with a first O-ring on the seat adjacent to the interior guard. The beveled seat has an exterior end with a cylindrical configuration constituting an exterior guard with a second O-ring on the seats adjacent to the exterior guard. The beveled seat has an intermediate guard on the seat between the first O-ring and the second O-ring.

Abstract: A pressure-limiting pump system for pressurizing a vessel, including a plunger terminating in a piston loose-fitting within a cylinder. The piston includes a flange forming the lip of an annular groove in the piston for supporting an O-ring seal. The groove is provided with a plurality of ports terminating in the piston within the cylinder. The O-ring is slidable on the piston groove surface. On the intake stroke, the O-ring moves to uncover the ports, and on the compression stroke, the O-ring moves to cover the ports to seal the compression chamber. When pressure exceeds a predetermined level, further compression causes air to bypass the O-ring and escape from the chamber, thereby limiting system pressure. The pump system may be mounted on-axis or off-axis in a tank sidearm. A handle is secured to the sprayer tank via shoulder inserts and is pivotable out of the way when filling the tank, yet can be locked in position as desired by a shift in pivot position.

Abstract: An apparatus for dosing lubricant into a compressed air flow includes a lubricant container, a pneumatically operated lubricant pump, an injection channel, a non-return valve interposed between the outlet of the pump and the injection channel, and an electronic sensor cooperating with or coupled to the non-return valve so that the sensor emits an electrical signal responsive and corresponding to the stroke travel of the non-return valve. When the pump carries out a lubricant injection cycle, the pressurized lubricant pushes open the non-return valve, flows into the injection channel and from there into a main channel through which compressed air flows. The travel of the valve is sensed by the sensor, and the sensor signal indicates whether the lubricant injection was proper or faulty, e.g. if the proper amount of lubricant was injected.

Abstract: A collapsible handle device for an inflator comprises an air cylinder having a shaft lever and a hollow grip, in which one end of the shaft lever is connected to a piston inside the air cylinder, and the other end is provided with a rotation body, which is pivotally jointed with the grip. A channel, wider than the diameter of the shaft lever, is formed in the lateral wall of the grip. The air cylinder could be inserted in the grip so as to reduce the volume of the inflator, or the air cylinder could be pulled out from the grip, then turned 180° to form a straight line with the shaft lever so that a user may hold the air cylinder with one hand and operate the shaft lever in axial direction to pump air out through an air vent at one end of the air cylinder.

Abstract: A pump includes a base, a tubular portion formed on the base and with an upper end and a lower end, a pressure gauge communicated with the tubular portion near the upper end, a cylinder communicated with the tubular portion near the lower end, a piston movably received in the cylinder, a rod connected with the piston and a nozzle communicated with the lower end of the tubular portion. The tubular portion defines a transverse channel. The cylinder defines an aperture. A first joint defines an axial channel and a transverse channel communicated with the axial channel. The first joint is received in the cylinder. A second joint defines an axial channel, a first transverse channel communicated with the axial channel thereof and a second transverse channel communicated with the axial channel thereof.

Abstract: A dual cylinder apparatus for a reciprocal hermetic compressor with a cylinder body having two open ends. A pair of valve plate units are disposed at both ends of the cylinder body, and have refrigerant discharge holes formed therein. A pair of pistons are movably disposed in the cylinder body and reciprocate therein. A piston bar having one end connected to a connecting rod is slidably supported on the valve plate units and reciprocate thereon while supporting the pistons. The piston bar has a refrigerant discharge hole through which a refrigerant, located in between the pistons, is discharged outside the cylinder body. A discharge valve movably disposed between the pistons opens one gap between one of the pistons and the cylinder body and closes a second gap between the other piston and the cylinder body.

Abstract: An oil-free air compressor is characterized in an air inlet provided at a lateral open end of a crankcase of the air compressor. External air enters into the crankcase via the lateral air inlet and then enters into a cylinder above the crankcase via a check valve provided on a piston head in the cylinder. Air in the cylinder is compressed by the piston head and then discharged to an air storage tank via a single air outlet provided on a cylinder head of the cylinder.

Abstract: A pump includes a cylinder housing having a mouth for a fluid to flow out of the housing and a port for the fluid to flow into the housing, a piston slidably engaged in the housing. A tube is coupled to the piston for allowing the fluid to flow out through the tube when the piston moves away from the mouth. A check valve may block the tube when the piston moves toward the mouth. Another check valve may block the port when the piston moves toward the port. Another housing includes a mouth for coupling and supplying a pressurized fluid to the previous housing.

Abstract: A compressor includes a piston slidably received in a chamber of a housing and having an annular groove for receiving a sealing ring, and having one or more conduits and having a number of openings communicating with the annular groove of the piston. The piston includes an inclined peripheral surface having a lower diameter greater the sealing ring for forcing the sealing ring to engage with the housing, and having an upper diameter less than that of the sealing ring for loosely receiving the sealing ring. A spring blade may selectively block the conduits of the piston.

Abstract: A compressor includes a piston slidably received in a chamber of a housing and having an annular groove for receiving a sealing ring, and having one or more conduits and having a number of openings communicating with the annular groove of the piston. The piston includes an inclined peripheral surface having a lower diameter greater the sealing ring for forcing the sealing ring to engage with the housing, and having an upper diameter less than that of the sealing ring for loosely receiving the sealing ring. A spring blade may selectively block the conduits of the piston.

Abstract: A high-volume low pressure hand operated air pump comprised of a tube body with a plunger shaft inserted into one end thereof and a check valve at the other end thereof with a floating seal secured to the internal end of the plunger shaft comprised of a captured double sided annular disk having a closed cell foam plastic seal on one side thereof and a plastic stiffener of the same plastic material integrated thereto for supporting the foam sealing side thereof

Abstract: A high-volume low pressure hand operated air pump comprised of a tube body with a plunger shaft inserted into one end thereof and a check valve at the other end thereof with a floating seal secured to the internal end of the plunger shaft comprised of a captured double sided annular disk having a closed cell foam plastic seal on one side thereof and a plastic stiffener of the same plastic material integrated thereto for supporting the foam sealing side thereof.

Abstract: An air compressor includes a pressure gage attached to a cylinder housing, a compression device having a piston container slidably received in the cylinder housing for supporting a compression valve and a positioning block and a valve piece and a limiting piece. A motor is secured to a seat. A gear is rotatably secured to the seat and driven by the motor and includes a weight pivotally coupled to the piston container with a link. The elements may be secured onto the cylinder housing and the seat separately before the seat is secured to the cylinder housing.

Abstract: An air compressor includes a piston slidably received in a housing, and a sealing ring engaged between the piston and the housing. The piston includes an aperture for air to flow into the housing. A spring blade has one end secured to the piston and the other end for resiliently blocking the aperture of the piston to form a check valve. A gear and a weight are secured to a base which is secured to the housing. The weight has an eccentric pin coupled to the piston. A motor has a pinion engaged with the gear for rotating the gear to move the piston up and down.

Abstract: The downhole pump has a barrel with a reciprocating plunger therein. The barrel has a first one-way valve, while the plunger has a second one-way valve. A barrel chamber is formed between the two one-way valves. The barrel chamber expands when the reciprocal movement between the plunger and the barrel is an upstroke movement and then contracts when the reciprocal movement is a downstroke movement. A bypass channel is provided between the barrel and the plunger so as to provide communication around the plunger and its one-way valve. The bypass channel is open when the reciprocal movement is near an end of the upstroke movement. When open, pressure across the plunger can equalize and gas inside the barrel chamber can vent around the plunger and/or pressure can equalize across the plunger one-way valve so as to prevent gas lock and minimize stress on the sucker rods.

Abstract: The invention relates to a pulse-triggered device for supplying an apportioned minimum amount of fluid, particularly oil for lubricating pneumatic systems. A valve actuated positive-displacement member may be moved using a pulse-triggered device located inside of a positive-displacement chamber, through which the fluid is supplied from a feeding channel to a discharge channel. A valve body, separate from the positive-displacement member is subjected to spring tension and may be lifted away from a valve seat connecting the two channels.

Abstract: A piston mechanism with a flow passage through the piston includes a cylinder which has a closable cylinder passage at one extremity thereof; a piston, axially movable in the cylinder, which has a closable piston flow passage and has in its outer circumference a groove in which a piston ring is situated for sealing between the piston and the cylinder; and a movement mechanism to axially move the piston in the cylinder. The movement mechanism includes a crank shaft which is mounted in a crank chamber and a piston rod which, on the one hand, is hingedly connected to the piston by a first bearing and, on the other hand, is hingedly connected to the crank shaft by a second bearing. The piston ring is mounted with a certain axial clearance in the groove. The piston flow passage extends over the groove and the piston ring forms a valve for closing and opening the piston passage.

Abstract: A single-piece piston for use in a pneumatically-activated pump or other metering device to meter a predetermined amount of lubricant or other liquid. The piston is disposed within a chamber of the body of the metering device. The piston has a grooved end that includes a head portion and a circumferentially-disposed angled channel for containing a sealing member such as an O-ring. An adjacent stem section includes means for providing a fluid-flow connection with the angled channel. Lateral movement of the piston within the body causes the sealing member to shift and block and unblock the fluid-flow connection means, which allows liquid from a liquid chamber to flow out the head of the piston's grooved end and to an adjacent pump chamber.

Abstract: A single-piece piston for use in a pneumatically-activated pump to meter a predetermined amount of lubricant or other liquid. The piston has a grooved end that includes a head portion and a circumferentially-disposed angled channel for containing a sealing member such as an O-ring. An adjacent stem section includes a longitudinally-disposed channel that is in fluid-flow connection with the angled channel. The piston is disposed within a chamber of the body of the pump. Lateral movement of the piston within the body causes the sealing member to shift and block and unblock the end of the longitudinal channel which allows liquid from a liquid chamber to flow into a slot and to a pump chamber adjacent to the head of the piston's grooved end.

Abstract: A pump includes a main body, a piston slidably received in the main body, and a hose having a first end attached to an end of the main body and a second end attached to the piston. A handle is attached to a piston rod, which, in turn, is attached to the piston. Air is outputted to a main passage via the hose during an outward stroke. Air is outputted to the main passage via a hole defined in the end of the main body during an inward stroke.

Abstract: A bicycle inflator includes a cylinder having a cap fixedly received in a first end thereof and an end member fixedly received in a second end of the cylinder. The cap has a passage defined therethrough. The end member has a tubular portion extending downwardly from a bottom thereof and the tubular portion has a cut-away defined through a periphery thereof so that a pawl member extending from the bottom is received in the cut-away. A piston rod extends through the end member and is connected to a piston member in the cylinder. A handle has a first end and a second end which is pivotally connected to the piston rod. A longitudinal recess is defined through a periphery of the handle and sized to allow the piston rod to pass therethrough. Each of two opposite inner sides defining the longitudinal recess has a notch defined therein and located near the first end so as to receive the pawl member when the handle is not used.

Abstract: An air pump is provided with an outer tube, a piston sealingly and slidably movable in the outer tube, an operating rod securely engaged with the piston and slidably received within the outer tube, a plug securely inserted into one end of the outer tube and allowing the operating rod to be slidably extending therethrough and an extension tube extending out from the other end of the outer tube. The operating rod has a channel adapted to slidably receive the extension tube therein. Therefore, when the extension tube is not in use, the extension tube is able to be received within the channel of the operating rod and the extension tube is able to be drawn out from the operating rod when in use to inflate a inflatable product.

Abstract: A single-piece piston for use in a pneumatically-activated pump to meter a predetermined amount of lubricant or other liquid. The piston has a grooved end that includes a head portion and a circumferentially-disposed angled channel for containing a sealing member such as an O-ring. An adjacent stem section includes a longitudinally-disposed channel that is in fluid-flow connection with the angled channel. The piston is disposed within a chamber of the body of the pump. Lateral movement of the piston within the body causes the sealing member to shift and block and unblock the end of the longitudinal channel and an aperture in the angled channel, which allows liquid from a liquid chamber to flow into a central bore in the piston and to a pump chamber adjacent to the head of the piston's grooved end.

Abstract: A compressor assembly includes a compressor mechanism mounted within a hermetically sealed housing. The housing is effectively divided into a low pressure area at a relatively low temperature and a high pressure area at a relatively high temperature. A motor and a lubrication system are contained within the low pressure area and the discharge side of the compressor mechanism is disposed in the high pressure area. A cylinder block effectively separates the high and low pressure areas of the compressor. The lubrication system includes an axial passage for communication oil from a sump to various compressor components, including rotational bearings. A seal cap is disposed at the end of the crankshaft that extends into the high pressure area and in combination with the cylinder block defines an oil discharge chamber at low pressure and isolated from the high pressure area.

Abstract: An air operated liquid pump includes a pump with a reciprocating plunger driven by a piston contained in a cylinder. The plunger is connected to and reciprocates a dispensing piston that moves between two positions relative to the plunger to open and close flow through valve holes that pass through the dispensing piston.

Abstract: The pump has a sleeve-like bearer. This contains a bush in which a piston is displaceable along an axis. The bearer inner surface and the bush outer surface are adjacent to one another in parts and are separated from one another in parts by an intermediate space. The inlet of the pump is connected through an intake chamber located at least partly inside the bush and through the piston, via a non-return valve, to a pump chamber, which is connected via another non-return valve to a primary outlet of the pump. The intermediate space connects the inlet and the intake chamber to a secondary outlet which is a distance away, along the axis, from the inlet and the intake chamber. During the operation of the pump, fluid flows from the inlet through the intermediate space to the secondary outlet and cools the bush.

Abstract: A vacuum system comprising a vacuum pump and a vacuum indicator. The vacuum pump comprises a cylinder, a piston disposed in the cylinder, a piston rod fixed to the piston and extending through an end of the cylinder, the rod being movable reciprocally, a sealing ring disposed on and around the piston and in engagement with an inside wall of the cylinder, and stops extending radially outwardly from the piston, the stops including a proximal stop and a distal stop, the sealing ring being axially movable between the proximal and distal stops, the piston having an axially-extending groove therein, the groove extending from proximal of the distal stop to proximal of the proximal stop, whereby upon movement of the piston in a first direction, the sealing ring engages the distal stop and seals an annular space between the piston and the inside wall of the cylinder, and upon movement of the piston in a second direction, the sealing ring engages the proximal stop and leaves unobstructed the axially-extending groove.

Abstract: A hermetically sealed reciprocating refrigeration compressor has a suction gas arrangement including a suction gas plenum formed integral with a cylinder block for supplying suction gas directly to a cylinder so as to eliminate the need for external suction gas conduits. Apertures are formed about the circumference of the cylinder for receiving suction gas directly from the suction gas plenum. Pistons are provided with multiple suction gas entrances and a semi-toroidal suction valve to provide an efficient way of introducing suction gas into a compression chamber during a suction stroke of the compressor. A spherical discharge valve assembly is provided in a valve plate adjacent the compression chamber for improved flow characteristics and increased through flow area.

Abstract: A highly manufacturable gas compressor includes a sheath removably attached to a piston by several resilient fingers that snap into place at the bottom of the piston. The fingers act to limit relative motion between the piston and sheath as the piston is reciprocated within a cylinder bore. During the suction stroke of the compressor, the piston and sheath separate at their tops, creating an opening at the top of the sheath which allows low pressure gas to flow through an opening formed in the side of the sheath, between the sheath and piston, through the opening at the top of the sheath, and into a compression chamber formed between the top surfaces of the piston and sheath and the bottom surface of a discharge valve.

Abstract: A hydraulic pump has a magnetic tube and two floating pistons within the tube, adapted to be moved in an axial direction within the tube as a result of magnetic flux generated by an electric coil surrounding the tube. Each piston has a valve for allowing fluid flow in one direction through the tube, and spring means acts on the pistons to control their positions. The arrangement allows operation with reduced vibration and pressure fluctuation, less heat and impact during dry running operation, and less heat and impact during high pressure shut-off.

Abstract: An air compressor including a cylinder, a motor, a reciprocating mechanism coupled to the motor, a compression mechanism reciprocated in the cylinder by the reciprocating mechanism to compress air, the compression mechanism including a base having a coupling bolt, a compressible conical piston holder and a compressible conical piston mounted around the coupling bolt of the base, wherein the coupling bolt of the base is inserted through the center holes of the compressible conical piston holder and compressible conical piston, having a head stopped above the compressible conical piston holder and the compressible conical piston, and a retainer rod raised from the head; a valve flap is slidably mounted around the retainer rod which opens the air passage through the compression mechanism during its down stroke, and close the air passage during its upstroke; a cap is mounted on the retainer rod to limit upward movement of the valve flap relative to the retainer rod.

Abstract: A toy pump device includes a tube in which a piston rod is slidably received, a piston connected to an end of the piston rod, the piston having a tubular portion extending therefrom with a first slot defined therein and a seal slidably mounted to the tubular portion, the tube having a protrusion extending therefrom so as to have a head mounted thereto which has a hollow tube, a member slidably received between the head and the protrusion wherein an inner tube extends from an inner periphery of the head and a second slot defined in the inner tube such that when pushing the piston rod, air enters into the hollow tube via a top hole defined in the end having the head mounted thereto and the second slot to inflate a balloon mounted to the hollow tube, and when pulling the piston rod, the member closes the top hole such that the pressurized air in the balloon is avoided from leaking.

Abstract: A drinking device for a diver includes a water container and a hand pump for pumping water to the diver's mouth. The hand pump includes a piston rod slidably engaged in a housing and two discs secured to the piston rod for separating the housing into an upper and a lower chambers. A passage is formed in the lower portion of the piston rod and has an aperture for communicating with a space formed between the discs. A sealing ring is slidably disposed in the space and may move upward to enclose the aperture for pumping the water in the lower chamber out of the housing. The sealing ring may also move downward to open the aperture for allowing the water in the upper chamber to flow into the lower chamber.

Abstract: A vacuum container including a container body, a cover covered on the container body, the cover having a top recess with air vents and a side opening, a switch mounted in the top recess and controlled by hand to close/open the air vents on the top recess for letting outside air flow into the container body, and an extraction pump mounted in the side opening on the container cover and reciprocated to draw air out of the container body.

Abstract: An object of the present invention is to provide a pump which suppresses a decrease in the volumetric efficiency of the pump to a great extent even in case that the kinematic viscosity of a fluid is high with a compact structure of the pump itself.