Abstract: A patient support apparatus supports a patient and includes a litter. A base is disposed below the litter. A lift mechanism is configured to move the litter and the base relative to one another between extended and collapsed positions. The lift mechanism includes first and second frame assemblies each including an outer frame member and an inner frame member arranged to move within the outer frame member. First and second rollers and first and second slide members are disposed between the outer and inner frame members. The first and second rollers are arranged to roll along at least one of the outer and inner frame members with a load exerted on the lift mechanism from the litter. The first and second slide members are arranged to slide along at least one of the outer and inner frame members with a load exerted on the lift mechanism from the base.

Abstract: A peristaltic pump for conveying a fluid guided in a hose includes a hose bed having a counter bearing to accommodate the hose, a support disk rotatable relative to counter bearing, a plurality of squeeze rolls positioned in the peripheral direction on the support disk and a plurality of guide rollers positioned in the peripheral direction on the support disk with a guide groove extending in the peripheral direction on its outer circumference, which forms a first guide plane facing the support disk. In order to be able to provide reliable loading and unloading of different hoses with different properties into the hose bed or from the hose bed, each guide roller has a guide cylinder above the guide groove to guide the hose during loading into the hose bed and/or during unloading from the hose bed.

Abstract: A piston apparatus may include a plurality of piston assemblies respectively having a first piston body and a first piston disposed within a first volume defined by the first piston body, a second piston body and a second piston disposed within a second volume defined by the second piston body, and a connection member coupled to the first piston and the second piston. The first and second volume may respectively include an expansion chamber and a compression chamber defined by opposite sides of the corresponding piston. The respective expansion chambers may fluidly communicate with a corresponding compression chamber of another one of the piston assemblies. The first volume of a first piston assembly may fluidly communicate with the first volume and the second volume of a second piston assembly, and the first volume of a third piston assembly may fluidly communicate with the first volume and the second volume of the second piston assembly.

Abstract: A hydraulic motor able to use low-pressure or high-pressure fluids such as water for a large number of applications. The motor uses a flow of water that is controlled and directed through a system of supply tubes to a chamber that fills with the fluid, moving a piston that produces an action such as rotating a shaft to turn a brush. Fluid fills the chamber through a system of opening and closing valves that direct and control the flow of the fluid so that the piston exerts pressure against a spring until it reaches a maximum position. A system of valves then reverses the flow of fluid until the piston is pushed in the opposite direction, producing an action such as turning a brush through the alternating application of water flows. A one-way gear box may be used to control the action of a shaft, which may be directed to turn in the same direction or in alternating directions to accomplish a wide variety of applications such as an hydraulic brush, gearbox speed increaser, generator or washing machine.

Abstract: An air-driven dual diaphragm pump comprises a pump body with a first air passage leading to a first air cavity with a first diaphragm, a second air passage leading to a second air cavity with a second diaphragm, and a reciprocating shaft which connects the first and second diaphragms. A diaphragm installation tool for the dual diaphragm pump comprises a plate which fits atop the pump body. A groove in a surface of the plate opposite from and nonadjacent to the pump body extends from the location of the first air passage to the location of the second air passage. A hole located within the groove at the location of either the first air passage or the second air passage extends through the plate. Pressurized air entering the pump body is redirected by the groove and the hole to always enter the first air passage, rather than the second, thereby slowly filling the first air cavity and positioning the second diaphragm for installation.

Abstract: A tool that is usable in a well and may include an operator, a switch, a resilient device and an indexer. The switch may be configured to selectively communicate a first force to the operator, thereby actuating the tool. The resilient device may exert a second force. The indexer may cycle through a sequence of positions in response to alternating between the second force and a third force. The sequence includes a predetermined position configured to actuate the switch, thereby communicating the first force to the operator to actuate the tool.

Abstract: A hydraulic motor able to use low-pressure or high-pressure fluids such as water for a large number of applications. The motor uses a flow of water that is controlled and directed through a system of supply tubes to a chamber that fills with the fluid, moving a piston that produces an action such as rotating a shaft to turn a brush. Fluid fills the chamber through a system of opening and closing valves that direct and control the flow of the fluid so that the piston exerts pressure against a spring until it reaches a maximum position. A system of valves then reverses the flow of fluid until the piston is pushed in the opposite direction, producing an action such as turning a brush through the alternating application of water flows. A one-way gear box may be used to control the action of a shaft, which may be directed to turn in the same direction or in alternating directions to accomplish a wide variety of applications such as an hydraulic brush, gearbox speed increaser, generator or washing machine.

Abstract: A vibrator has a hollow body with two end walls, a first piston slidably housed within the body, a first chamber defined therein and communicating with an inlet and bounded by a first active surface of the first piston, and a second chamber bounded by a second active surface of the piston, larger than and opposite the first active surface. The first piston slidingly houses a switch unit having at least one second piston and controlled by a fluid switch circuit having an inlet portion formed in the first piston and communicating with the first chamber. An outlet portion is formed in the first piston and communicates with the outlet. A switch portion, which is defined by the switch unit, communicates with the second chamber, and connects the second chamber to the inlet portion and to the outlet portion alternately as a function of the switch unit's axial position.

Abstract: An internal combustion engine having a generally rotary design is described. The engine includes a rotor that alternately rotates about first, second, and third axes of rotation as the rotor circulates within the engine. Each axis of rotation is about perpendicular to the other two axes of rotation. The rotor includes two flanges that alternately compress fluid in combustion chambers as the flanges rotatably enter and sweep through compression lobes. Detonation of compressed, combustible fluid occurs in the combustion chambers, force from the detonation driving the rotor about the axes of rotation. The rotor exerts maximum leverage on a power shaft at the point of detonation, and continues to exert similar leverage on the power shaft as the rotor rotates. The engine typically includes one or more power modules, each of the one or more power modules having three compression lobes and three combustion chambers.

Abstract: A fluid-working machine comprising a ring cam, at least one piston defining a working chamber, and at least one valve associated with the or each working chamber for connecting the working chamber alternately to low and high pressure manifolds in phased relationship to cycles of working chamber volume. The ring cam has a wave-like cam working surface for operative engagement with the at least one piston. The waves of the wave-like cam surface each having a leading face and a trailing face and discontinuities, such as apertures to retain bolts, are located in the working surface on whichever of the leading face and the trailing face the at least one piston does least work during normal operation resulting from the flow of fluid into and out of the working chamber in phased relationship to cycles of working chamber volume.

Abstract: A fluid distributor cylinder is for a percussive drill assembly that includes a casing having an inner circumferential surface defining a central bore, a central axis extending through the bore, a bit movably coupled with the casing and a piston movably disposed within the casing bore. The distributor cylinder includes a generally tubular body disposeable within the casing bore and having first and second ends, a central axis extending generally between the first and second ends, an outer circumferential surface. At least a section of the outer surface is configured to engage with the inner surface of the casing so to form an interference fit between the body and the casing. The cylinder includes an exterior thread and/or a radially-extending shoulder configured to releasably engage with the casing inner surface so as to substantially prevent axial displacement of the distributor body with respect to the casing.

Abstract: A hydraulic motor with rotating shaft coupled to a piston with alternating rectilinear displacement. The hydraulic motor comprises a casing enclosing a rotating shaft, a piston and an inverter comprising a first sleeve formed as one piece with the piston, a second sleeve, fixed in position, and a distributor mounted so as to rotate in the interior of the second sleeve and conduit and hole elements arranged between the second sleeve and the distributor and means for controlling the rotation of the distributor as a function of the displacement of the first sleeve so as to invert the direction of displacement of the piston.

Abstract: A hydraulic motor with rotating shaft coupled to a piston with alternating rectilinear displacement. The hydraulic motor comprises a casing enclosing a rotating shaft, a piston and an inverter comprising a first sleeve formed as one piece with the piston, a second sleeve, fixed in position, and a distributor mounted so as to rotate in the interior of the second sleeve and conduit and hole elements arranged between the second sleeve and the distributor and means for controlling the rotation of the distributor as a function of the displacement of the first sleeve so as to invert the direction of displacement of the piston.

Abstract: Reciprocating pumps are disclosed. Particularly, reciprocating pumps including pressure chambers and fluid chambers defined by flexible members are disclosed. The volume of the pressure chambers and fluid chamber may be controlled using a piston driven by the flow of a control fluid to a pressure chamber and associated piston chamber. The flow of the control fluid may be directed to a first pressure chamber and associated piston chamber or a second pressure chamber and associated piston chamber. A pneumatically driven switch or an electrically driven switch may direct the flow of control fluid. The electrically driven switch may be controlled with a timer, a pressure sensor, or an optical sensor. The reciprocating pump requires minimal modification to permit the use of a pneumatic switch or electrical switch.

Abstract: The invention relates to a control valve, a percussion device and a method of controlling a working cycle of a percussion device. A percussion device (1) for breaking rock includes an impact element (8) controlled by a control valve (2). The control valve includes a control element (5) arranged to control channels (7b) leading to a working pressure surface (9) of the impact element (8). The control element, during a working cycle of the control valve, is arranged to open and close pressure channels at several connecting moments so that during one working cycle of the valve, several impact pulses are arranged to be produced.

Abstract: The invention relates to a control valve, a percussion device and a method of controlling a working cycle of a percussion device. The percussion device (1) used for breaking rock comprises an impact element (8), which is controlled by a control valve (2). The control valve comprises a control element (5), which is arranged to control channels (7b) leading to a working pressure surface (9) of the impact element (8). The movement of the control element to its extreme position is arranged to form a closed pressure space, where pressure medium compresses and converts kinetic energy of the control element into pressure energy. The pressure energy is re-converted into kinetic energy and utilized when the control element changes its direction.

Abstract: In one embodiment a pneumatic motor is provided that includes an intake chamber in fluid communication with at least one intake channel. Each intake channel is further in fluid communication with a corresponding cylinder, which receives a piston that cycles upwardly and downwardly to rotate a motor axle. A member is placed in each intake channel to seal the corresponding cylinder from each intake channel when compressed fluid in the intake channel has a higher pressure then pressure in the corresponding cylinder. Each piston includes an actuator extending downwardly from the piston and having a profile that, during a portion of the upward cycle of the piston, causes the actuator to push the member back into each intake channel to allow compressed fluid into each of the corresponding cylinders. Each piston includes an intermediate section that has an annular groove, a seal positioned in the groove that creates a fluid tight seal against the corresponding cylinder during the upward cycle of the piston.

Abstract: A reduced icing valve for an gas-driven motor and a reciprocating double diaphragm pump is provided having a shiftable valve for alternatively supplying a motive gas through first and second supply ports to opposed first and second power pistons in opposed motive gas chambers, respectively, and for effecting alternating exhaust of the chambers. The shiftable valve is provided with an insert that deflects, away from the shiftable valve, air entering from each of the bypass valves until the bypass valves are fully actuated by the exhaust gas from the motive gas chambers. The shiftable valve is further provided with bypass valves independent of and intermediate the shiftable valve and each of the first and second motive gas chambers for bypassing the shiftable valve by exhaust gas from the motive gas chambers. The bypass valves are further actuated in an opposing direction by a supply source of motive gas to the chambers.

Abstract: A pneumatic motor assembly for a lubricant pump comprises a body which forms a cavity supplied with compressed air, a first hole and a second hole which are formed axially on the side wall of the cavity, a stem, which is slidingly accommodated in the first and second holes and supports, at one end, a piston which moves in a cylinder associated with the body and, at the other end, cooperates with the riser of the pump.

Abstract: A transducer includes a linear input power source (12) connected to a connecting rod (24) in turn connected to output drive shafts (30 & 36) through one-way clutches (28 & 40), with the output drive shafts being interconnected through gears (32 & 40) such that when one shaft is powered, the other is coasting. The power source includes multiple stern powered cylinders (16 & 94). Inlet and outlet valves (44) for each cylinder chamber are controlled by an actuator (56) which instantaneously snaps the valves between open and closed positions. The power cylinders (16 & 94) may be operated individually, in parallel or in series and as required, a valve passageway through the piston (18) may be operated to equalize pressure. A pair of O-rings (121) on the piston (18) engage the cylinder wall only when the adjacent chamber is pressurized, thereby reducing drag in operation of the piston.

Abstract: A piston for a fluid-actuated, percussive, down-the-hole drill is provided with self-lubricating bearings and self-lubricating seals within the drill to provide a drill requiring no oil lubrication.

Abstract: A true random vibration generator for use in mechanical vibration generation includes a housing, a piston, and a programmer. The housing defines a cylinder closed at an impact end. The piston is slidably disposed in the cylinder and propelled by a pressurized gas. The programmer is freely moveable in the cylinder between the piston and the impact end of the cylinder. As the piston is propelled towards the impact end of the cylinder by the pressurized gas, the piston strikes the programmer causing the programmer to randomly bounce between the impact end of the cylinder and the piston. The bouncing continue until the programmer impacts the housing and the cylinder at substantially the same time. The piston is then propelled back its original position by the pressurized gas and the impact with the housing. The above described piston cycle is repeated and continues to impart vibration energy to the housing.

Abstract: A balanced compound, regenerative cycle, external heat source engine is mad by using mechanically double acting rigidly affixed and self-aligned reciprocating opposed piston and cylinder structure in which substantially all of the energy created during reciprocating motion is converted or translated into rotational motion by the action of a scotch yoke type, transfer lubricated, sliding/roller bearing mechanism which acts on a single and centrally located crankshaft which is contained in a telescopic crankcase structure. A balanced compound engine structure may be constructed so that two or more subsystems are housed in one or more modules. Two or more power modules may then be coupled together and an engine power and speed control may be attained by varying the relative phase angle of the couple.

Abstract: The invention relates to a piston vibrator comprising a case with at least one cylindrical bore (5), at least one air connection (7) taken laterally to the bore (5), and a piston (2) longitudinally displaceable in the bore (5). As a means of making such a vibrator more efficient with a given outside diameter, or as a means of making it more compact and smaller with the same degree of efficiency, the invention proposes that the cylindrical bore (5) should extend asymmetrically to the external wall area (6) of the case, at least at the axial level of the air connection (7).

Abstract: A vibration cancellation device is provided for an air motor with a reciprocating drive piston. The device consists of an anti-phase piston which is axially aligned with the drive piston and reciprocates in the opposite direction of the drive piston. In one embodiment, the stroke of the anti-phase piston is adjustable to permit optimizing its vibration cancellation characteristics.

Abstract: A pneumatic reciprocator includes a cylindrical air cylinder concentrically mounted within a cylindrical manifold. A cylindrical sleeve valve is concentrically mounted for movement along the manifold by a pair of spaced O rings. Two sets of circumferentially arranged air holes in the manifold are alternately covered and uncovered by the O rings as the sleeve valve is moved to selectively pressurize and vent opposite sides of the piston in the air cylinder. Movement of the sleeve valve is controlled by stops on the movable bed of a surface grinder that is controlled by the air cylinder.

Abstract: A down-hole percussion drilling tool supplied with compressed air includes a piston reciprocated in an enclosed cylinder against a bit. A spool is continuously reciprocated in a valve chamber by a pilot fluid pressure supply, tapped from the compressed air from a major air flow passage to either a first or a second feed passage. Compressed air conducted through the first feed passage accelerates the piston toward the bit and compressed air conducted through the second feed passage accelerates the piston away from the bit. The continuous reciprocation of the spool is independent of the position of the piston relative to the cylinder.

Abstract: A power driver and method of pile driving. The invention encompasses a pile driver having a ram, cylinder and piston arrangement mounted in a framework, such arrangement being typical of those power drivers of the prior art. A compressible fluid, such as air or steam, enters into the cylinder through an intake port and leaves through an exhaust port. Both ports are controlled by a common valve. Expansion of the steam within the cylinder acts against the piston causing the piston rod to rise thus raising the ram and an associated slide bar. As the slide bar rises, it triggers the valve to move into a position effecting closure of both intake and exhaust ports. Further rising of the piston effects movement of the valve into a position wherein the intake port remains closed and the exhaust port is opened, thus exhausting the excess steam. Movement of the valve by elevation of the slide bar at each stage of movement is effected through triggering of cam followers or trips by cams on the slide bar.

Abstract: A pumping unit for actuating a linear reciprocable pump rod comprises a frame having a pair of spaced apart vertical guides for guiding vertical reciprocating movement of a traveling pulley assembly connected to a linear extensible hydraulic cylinder mounted on the frame directly under the pulley assembly. The pulley assembly includes two rotatable sheaves over which are trained, respectively, flexible cables which are anchored at their opposite ends to the frame and to a bracket connected to the pump rod. The arrangement provides a single purchase pulley system providing for a pump rod stroke length of twice the stroke length of the cylinder actuator. A hydraulic control system for reciprocating the cylinder includes a solenoid operated valve which is controlled by a cam actuated switch to alternately provide for conducting hydraulic fluid to and from the cylinder. The valve actuating switches are tripped by spaced apart cams mounted on a rod connected to the pulley assembly.

Abstract: A winding arrangement suitable for sheeting in a sail of a yacht comprising a winch drum and a piston cylinder assembly having a double-acting piston which is reciprocable within a cylinder. A rack member, coupled to the piston, produces unidirectional rotation of the winch drum through a particular clutch and gear system. A manually operated pump is arranged to supply fluid under pressure to the piston-cylinder assembly through supply pipes and a valve which directs the fluid supplied by the pump to opposite ends of the cylinder alternately, thereby to reciprocate the piston and rotate the winch drum.

Abstract: A body support such as a bed, operating table or seat has a flexible top sheet secured over the sides and ends of a frame, and resting on a series of parallel resiliently deformable rollers located between the sides of the frame and supported, in turn, by a longitudinally reciprocal substantially horizontal bearer plate, which is driven back and forth causing the rollers to roll back and forth under the top sheet, thus constantly changing the main pressure areas of the body supported by the top sheet.

Abstract: An oil well pump jack with dual hydraulically operated piston and cylinder assemblies for pivoting the walking beam of the pump jack and including a unique control arrangement for controlling operation of the piston and cylinder assemblies. The pump jack includes a unique base or skid and an adjustable knee brace assembly to facilitate positioning of the pump jack in properly supported relation to the oil well at the oil well site. The control arrangement for the piston and cylinder assemblies includes a reversing valve, a linkage mechanism for operating the reversing valve to cause controlled oscillation of the walking beam and a cushioning device for controlling acceleration and deceleration of the oscillating walking beam to reduce abrupt tension forces exerted on the polish rod and sucker rods and impact forces imparted to the pump jack during oscillation of the walking beam.

Abstract: A pumping jack for use with a well having a vertically reciprocable polish rod has a base including a horizontally extending table. A hydraulic cylinder is mounted on the base, with the cylinder axis extending parallel to and above the table. A plunger is reciprocable in the cylinder along the axis and carries with it a block including a first sheave around which a first flexible line is reeved. One end of the first line is affixed to the base, and the other end of the first line extends around a well sheave mounted on the base with the well sheave periphery tangent to the polish rod, the line from the well sheave being affixed to the polish rod. The reciprocating parts are balanced at least in part in either of two ways. In one way, there is a pneumatic chamber variable in volume in accordance with the reciprocation of the polymer and provided with air under an elevated pressure sufficient to counterbalance or offset part of the reciprocating load.

Abstract: A hydraulic engine having a fluid pump for pumping a fluid medium under pressure to a fluid motor connected to the pump for being actuated by the fluid medium under pressure received from the pump. A control system regulates operation of the pump and motor so as to permit appropriate variation of speed of an output shaft of the motor. The fluid motor is a reciprocating motor, the piston of which is connected directly to a mechanism for translating the reciprocating motion into rotary motion, while the reciprocating movement of the pistons simultaneously actuates valves for sequentially directing the fluid medium under pressure to opposite ends of the piston in order to obtain a double-acting piston and cylinder operation.

Abstract: A flow control valve assembly for controlling the flow of a working fluid which has a housing that defines a valve chamber therein, an inlet port to the valve chamber and an outlet port from the valve chamber, a valve body which is movably carried in the chamber between a closed position that blocks the outlet port from communication with the inlet port and an open position so that the inlet port is in communication with the outlet port to allow the working fluid to be forced through the valve chamber, and a valve control means responsive to the velocity of the working fluid flowing through the valve chamber or responsive to the pressure differential across the valve body to operate the valve assembly by moving the valve body between the open position and the closed position.

Abstract: A hydraulically operated oil well pump jack utilizing a double acting hydraulically operated piston and cylinder assembly for pivoting the walking beam of an oil well pump jack, a linkage mechanism for operating a reversing valve to cause extension and retraction of the piston and cylinder assembly for oscillating the beam about a saddle bearing at the upper end of a stanchion or samson post together with a crossover cushioning device for controlling acceleration and deceleration of the oscillating walking beam to reduce abrupt tension forces exerted on the polish rod and sucker rods and also reduce impact forces on the oil well pump jack during oscillation of the walking beam.

Abstract: A hydraulic drive circuit for machine tools, such as power shears, press brakes, and the like having hydraulic cylinder reciprocated members, controls fluid flow to and from the hydraulic cylinders to automatically move and hold the member in an idle position, to apply power in the desired direction upon demand, and to bypass fluid for unloading the pump until power is demanded. In power shears and press brakes, the vertically movable ram is automatically raised and held in an out-of-the-way position whenever the manually actuated control is released even after stoppage of the pump.

Abstract: A jack pump, such as the type capable of use in pumping crude oil from an oil well, the jack pump including a double acting piston and cylinder motor with the piston rod of the motor being adapted to be connected to the polished rod projecting upwardly from a well head. A variable displacement hydraulic pump, which is driven by a motor or engine, is included in a closed hydraulic loop wherein conduits are connected to a pair of output ports of the pump. A pump control means controls the direction and volume of flow in the loop so as to establish a total velocity profile during the complete pumping cycle and to determine the length and position of the stroke of the piston rod.

Abstract: A walking beam pumping unit is provided for pumping liquid from wells having gas pressure therein. The unit is driven by gas pressure from the well reciprocating the piston of a pneumatic cylinder up and down to swing the walking beam correspondingly and pump the liquid from the well. Gas under pressure is directed from the wellhead through a two-way valve to the opposite ends of the hydraulic cylinder in alternating fashion, so the piston has power strokes in opposite directions. Each power stroke, besides moving the walking beam, serves to recompress the gas used for the preceding power stroke sufficiently to inject it into the sales line. The setting of the two-way valve is controlled by a pneumatic actuator supplied with gas under pressure from the wellhead and having a thimble valve responsive to the up and down movement of the walking beam by means of adjustable stops carried thereon.

Abstract: A fluid operated reciprocatable device has an outer, usually fixed, member nd an inner relatively movable member joined by a resilient member e.g., of rubber. The outer member is closed at one end so as to form an enclosure into which fluid under pressure can be admitted so as to displace the inner member in a given axial direction relative to the outer member. When a pulsating pressure is applied to the fluid the inner member vibrates axially in accordance with the pulses. The resilient member is proportioned so that its dimension in the axial direction is large in comparison with the thickness between the outer and inner members, e.g. 4 times larger. The properties of the resilient member are chosen so that it acts not only as a seal between the outer and inner members to contain fluid, but as a return spring whereby the inner member is returned, between fluid pulses, from an axially displaced position.

Abstract: A percussion tool is hydraulically operated by a piston whose stroke is controlled by a spring biased valve. A pressure accumulator is connected to the working pressure chamber of a hydraulic cylinder and receives pressure therefrom during the return stroke of the piston while discharging pressure during the working stroke. A piston is displaceably mounted in the pressure accumulator for movement into an end position when the pressure is discharged and a second valve is actuated by the piston in the end position to control the spring biased valve.The invention refers to an improvement in hydraulic percussion tools.Hydraulic percussion tools, for rock drilling, breaking or the like of known construction have a reciprocating working piston in a cylinder, driven by a pressure liquid, usually hydraulic oil, during the reciprocating movement.