Abstract: A bellows pump with the improvement of an adjustable index for uniformly controlling the amount of fluid displaced in each expansion and compression cycle.

Abstract: A portable hydraulic tool, such as a hydraulic secateurs, is of the kind having a single acting ram including a driving piston with its piston rod connected to at least one movable operating member such as a cutting element of the tool, the piston being movable in fluid tight manner in a bore under the thrust of hydraulic fluid acting on a working face of the piston, the improvement being that there is provided a return chamber the volume of which decreases when the driving piston is displaced in its working stroke, the return chamber containing a compressible fluid under pressure such that, when the thrust exerted on the piston by the hydraulic fluid becomes less than the thrust exerted on the piston by the compressible fluid, the piston is caused to carry out a return stroke by the expansion of the compressible fluid.

Abstract: A double action piston/cylinder unit has a piston guided in a cylinder and attached to a piston rod, the piston to be charged with a pressure agent, particularly hydraulic fluid at a first end face, the hydraulic fluid to be conducted in a controlled manner into the cylinder via a first fitting disposed at an end section of the cylinder and is to be charged at its other, second end face with a pressure agent which is located in an annular chamber formed by a central section of the piston rod and the inner wall of the cylinder, the second end face of the piston and a cylinder end piece, the annular chamber is in communication with a pressure agent reservoir which is connected to the annular chamber via a second fitting disposed at the other end section of the cylinder.

Abstract: A nitrogen die piston-cylinder unit has a central post threaded at one end into a nitrogen manifold. The piston has an axial bore therethrough. A sleeve closed at one end is telescoped over the free end of the post and is vertically slideable thereon. The upper end of the post has an annular seal thereon in sliding sealed engagement with the bore of the sleeve. A key and keyway formed on the inside of the sleeve and the outside of the post are arranged to interengage when the sleeve is fully telescoped over the post to prevent relative rotation therebetween. The exposed end face of the sleeve is formed with recesses adapted to be engaged by a spanner wrench to enable the unit to be removed from the threaded port of the manifold when the key is engaged with the keyway.

Abstract: An electrically operated injection pump having an eccentrically mounted cam for reciprocating a spring-biased plunger, said plunger causing the receiving of injection fluid during intake stroke, and the ejection of such fluid during the exhaust stroke.

Abstract: The present invention provides an actuator comprising a hydraulic cylinder whose rod is connected to the shaft driving the controlled device by means of a transmission. The end of the rod of the cylinder penetrates into an accumulation chamber connected to the intake circuit of said cylinder through a distribution circuit comprising at least one non return calibrated valve and a balancing distributor with push rod and spring return which allows the drive fluid of the cylinder to be admitted into said accumulation chamber when the rod of said cylinder is at the end of travel under the effect of the drive fluid.

Abstract: Table couplings for coupling hydraulic actuators to large shaking tables, such as earthquake simulator tables are preloaded under gaseous pressure to permit the couplings to be nontension carrying couplings, which in turn permits use of hydrostatic slip bearings between the side surfaces and the bottom surface of the table and the actuators. The hydrostatic bearings in turn reduce the need for swivels, links and yokes that carry both tension and compression. The use of compression only loading such as that permitted with the present device, also reduces the problem of making a satisfactory table foundation, because only compression loads are carried to the foundation rather than alternating tension-compression loads.

Abstract: A piston-cylinder unit for use in a die is threaded into a port of a nitrogen manifold. The piston has a seal thereon slideably engaging the cylinder bore and has a rod projecting out one end of the cylinder, the rod being biased by the gas pressure at the threaded end of the cylinder into engagement with a die member reciprocated in response to reciprocation of the ram of the press in which the die is mounted. The portion of the cylinder threaded into the manifold has a bleed passageway therethrough which communicates with the interior of the cylinder below the seal on the rod when the press ram is at bottom dead center position and with the interior of the cylinder above the seal on the piston when the piston rod is fully retracted.

Abstract: The invention relates to a hydraulic actuator for the control of valves such as the kind found in ships. The actuator has a piston which is actuated in a valve opening direction with a hydraulic pressure medium and may be actuated in the return direction by a gas-compression type spring. Certain emergency situations require an immediate closing of a valve or group of valves controlled by the piston acting through a spindle. Emergency closing apparatus includes an abutment on the piston which forms an annular chamber when the piston abuts the end wall of the piston cylinder. The housing has an emergency passage means in fluid communication with the annular chamber when the piston abuts the end wall to effect an emergency moving of the piston in a valve closing direction when a pressure medium is admitted into the emergency passage.

Abstract: A spool valve for use in a hydraulic ram includes a piston journalled for axial movement within a cylinder under the influence of a fluid fed under pressure to the cylinder. The spool valve is journalled within a valve block closing an end of the cylinder through which passes a piston rod. The valve is biased from one position to another by means of differential areas of a circumferential groove around the spool and by applying fluid to a chamber at one end of the spool.

Abstract: A compact hydraulic control device for use with mining apparatus is composed of a housing block containing tappet-operated valves. A multi-part cam shaft serves selectively to operate the valves by displacing the tappets by manual control effected by external levers. To automatically restore the cam shaft back into a neutral position as a "dead-man's handle" restoring system use is made of a pair of piston and cylinder assemblies mounted as detachable cartridges in parallel locations within bores in the housing block and having push rods which act on a cam of the cam shaft under the action of hydraulic or pneumatic pressure medium.

Abstract: A dispenser for dispensing controlled quantities of liquid from a bottle includes a piston, which is movable in a cylinder and serves to suck and discharge an adjustable quantity of liquid. The cylinder is secured to a valve block, which contains a suction valve and a discharge valve. A cylindrical sleeve surrounds the cylinder and defines an annular clearance therewith. To change the length of the stroke of the piston and the quantity of liquid which is to be sucked and discharged depends on the stroke length, an adjustable stop and a fixed stop, which is engageable with the adjustable stop and are accommodated in the clearance.

Abstract: A cylinder driving system comprising balance cylinders communicated to an accumlator for supporting a load under balanced state, a drive cylinder of a small diameter connected by way of a switching control device to an air source for driving the load with reduced air consumption and a speed controller provided either to the balance cylinders or to the drive cylinder for switching the load driving speed between high and low speeds.

Abstract: A power cylinder of a hydraulic percussion implement, in whose bore a ram with an enlarged piston head is vertically reciprocable to strike a tool at the lower end of the bore, has a control chamber above the piston head alternately communicating with the high-pressure side and the low-pressure side of a source of hydraulic fluid, an annular recess in the bore being permanently or intermittently connected to high pressure acting upon the underside of the piston head. An annular drainage chamber formed by the bore at a lower level, disposed above an oil seal, collects liquid leaking down from that recess and returns it to the source. A pneumatic buffer lies in or communicates with that drainage chamber for absorbing hydraulic shocks generated when the ram strikes the tool.

Abstract: A control apparatus for internal combustion engines, which generates an adjustment path on the path of an adjustment member which is proportional to the air mass supplied to the engine. The control apparatus contains a counterpart pressure chamber sealed off from the outside and separated in a pressure-tight manner by an adjustment diaphragm from a first pressure chamber exposed to induced air pressure. A pressure source generating a reference absolute pressure which is constant under all operating conditions is connected to the counterpart pressure chamber. Consequently, the apparatus performs the function of a charge pressure stop equipped with a diaphragm box. The air reservoir of an air pressure brake system, a reservoir charged with the exhaust gas counterpressure or charge air pressure, or a vacuum pump can serve as the pressure source, and an absolute pressure controller controls the reference absolute pressure prevailing in the counterpart pressure chamber.

Abstract: A yoke type engine wherein the orbital path of the slider is alterable to effect piston stroke and compression ratio changes. A crank component has a crankpin which carries and positions the slider. A boss of the crank component is carried by a control shaft in an offset manner. Timing gears normally drive the control shaft in synchronization with the crankshaft to maintain a constant stroke and compression ratio. Relocation of certain timing gears by an actuator causes the control shaft to rotationally advance or retard to reposition the crank component carried thereby to in turn alter the orbital path of the coaxial crankpin and slider relative to a crankshaft axis. Accordingly, high and low compression orbits for the slider may be effected to best suit engine loads. A variable length throw couples the slider to the crankshaft. The orbital path of the slider provides increased crankshaft leverage over conventional engine arrangements.

Abstract: A vacuum pump assembly which is driven by pulsating exhaust gases emanating from an internal combustion engine is disclosed.

Abstract: A system for resiliently supporting a load at a reference height includes a hydraulic cylinder for resiliently supporting a load about a reference height and an accumulator which cooperates with the cylinder for flowing hydraulic fluid therebetween in response to varying loads imposed on the cylinder. A valve is provided for dampening the rate of fluid flowing between the cylinder and the accumulator and a metering valve coacts with the cylinder for adjusting the reference height about which the load is supported.

Abstract: Hydraulic fluid pressure moves a piston (22) against a body of incompressible fluid (14), compressing a spring (42). The pressure is released, and the force of the stored energy in the spring (42) is transmitted to the piston (22) by the body of fluid (14) and drives the piston (22) through its power stroke. The fluid (14) is vented to an outlet (8) before the piston (22) reaches the end of its power stroke, removing the force from the piston (22) and allowing it to free travel through the remainder of the stroke. When the motor (2) is operating and the load is removed from the piston (22), the hydraulic fluid inlet (10) is short-circuited to the outlet (8) and the motor (2) automatically shuts off.

Abstract: A force limiting device for an actuator rod is used on a valve actuator of the type which includes hydraulic fluid being selectively applied to and discharged from a cylinder at a first side of a piston connected to the actuator rod as high pressure gas of an accumulator mounted on the cylinder acts in opposition thereto on a second side of the piston. The piston includes an interior cylindrical bore narrowing to an opening at the first side thereof which receives the actuator rod slidably therein. The actuator rod extends from the first side of the piston through a hole in the first end of the cylinder for coupling to a valve stem outwardly of the cylinder. An enlarged piston head is secured at a first side thereof to the other end of the rod and disposed within the interior cylindrical bore for sliding, sealed contact with an interior of the bore. Atmospheric pressure communicates with the bore to act on the second side of the piston head.

Abstract: A fluid actuated shift bar housing assembly for a change gear transmission wherein the shift bars are biased to an axially centered neutral position by constant fluid pressure in a constantly pressurized chamber and are selectively axially moved to an axially displaced gear engaged position by selective pressurization of a selectively pressurized chamber. A detent mechanism is provided for retaining the shift bars in the displaced positions thereof, said detent providing a resistance to axial movement of the shift bars having a smaller axial magnitude than the axial centering bias of the constant fluid pressure.

Abstract: A liquid pressure striking device defines a double-acting cylinder in a main body thereof having a tool at its lowest portion, and the double-acting cylinder houses therewithin a piston having an upper rod and a lower rod. The lower rod suspends a hammer for striking the tool, and the upper rod is provided on its outer circumference with a change-over valve mechanism which comprises a valve body of special structure for automatically switching the liquid flow under pressure by vertical movement of the piston, and a valve chamber having a plurality of concaves for controlling said valve body. Above the upper part of the valve chamber, there is provided an accumulator serving as a cap or cover of the main body. The main body is formed with an inlet passage of the liquid and an outlet passage, communicating with the accumulator and the valve chamber.

Abstract: A control apparatus for internal combustion engines, which generates an adjustment path on the part of an adjustment member which is proportional to the air mass supplied to the engine. The control apparatus contains a counterpart pressure chamber sealed off from the outside and separated in a pressure-tight manner by an adjustment diaphragm from a first pressure chamber exposed to induced air pressure. A pressure source generating a reference absolute pressure which is constant under all operating conditions is connected to the counterpart pressure chamber. Consequently, the apparatus performs the function of a charge pressure stop equipped with a diaphragm box. The air reservoir of an air pressure brake system, a reservoir charged with the exhaust gas counterpressure or charge air pressure, or a vacuum pump can serve as the pressure source, and an absolute pressure controller controls the reference absolute pressure prevailing in the counterpart pressure chamber.

Abstract: The preferred embodiment is directed to an oil well pumping apparatus incorporating a walking beam having a horsehead at one end which connects to the sucker rods in the oil well. The opposite end of the walking beam is supported on a fixed pivot. A hydraulic and pneumatic combination unit connects from a supporting platform to a central point on the beam to raise and lower the beam. The improved apparatus utilizes air pressure to balance the static load on the apparatus and dynamically strokes the sucker rod string by imparting a reciprocating motion through hydraulic power applied at a specified rate to raise and lower the walking beam. A pump and motor system for a closed hydraulic loop is included. Alternate preferred embodiments are disclosed. In one form, a lubricating system is incorporated. First and second alternate forms of pickoff apparatus which powers the pneumatically balanced pumping apparatus is also included.

Abstract: A liquid storage tank for providing a liquid under pressure in such a way that pressurized air will not be absorbed by the liquid is disclosed. According to one embodiment of this invention, the pressurized storage tank of this invention having side walls and an end wall uses a plunger or a plate having a seal which is biased to move within the tank as water or liquid is forced into the tank or withdrawn from the tank. According to this embodiment, springs may be positioned in different arrangements and used to provide the bias that maintains the water or liquid under pressure. Still other embodiments use mass or weight while still others use power actuated means or air pressure for providing the necessary bias. In other embodiments of the invention, the tank may include a seal and/or a collapsable liner to prevent any of the liquid from passing the plunger or piston. The addition of a collapsable liner is especially useful if the liquid to be maintained under pressure is corrosive.

Abstract: A hydraulic percussion machine, comprising a body carrying hydraulic passages and valves, and having a gas-filled, hydraulic pressure accumulator for storing the stroke energy which accelerates a piston to strike against a tool. The percussion machine has a separate hydraulic stroke standardizing circuit by action of which the piston stroke is independent of the liquid pressure in the high pressure line supplying the machine and of the volumetric flow.

Abstract: An all-hydraulic impactor for percussion tools and the like embodying an oil accumulator and an annular sleeve valve. Hydraulic fluid is initially supplied to the accumulator at full supply pressure and is then charged, for example, to three times the supply pressure by a differential piston arrangement. The impactor of the invention minimizes the required volume of the accumulator.

Abstract: A hammer or impactor apparatus including improved motive fluid means cooperable with spring bias means to reciprocably drive a hammer element and an improved process of hammer cycling achieved thereby.

Abstract: An impactor apparatus including novel means for actuation of a motive fluid flow control valve or comparable motive fluid control means.

Abstract: A vacuum motor for controlling a carburetor choke valve in which the stroke of the motor is limited to a predetermined length for a predetermined period of time after which the length of stroke is increased a predetermined amount.

Abstract: An apparatus for use in the generation of impulses, comprising a stepped piston assembly having a large piston and a small piston mechanically linked to one another and reciprocable between forward and rearward positions with the large piston being located in a large cylinder and having a large rearward face in communication with a reservoir for compressed fluid, and with the small piston having a small forward face for delivering the impulse; wherein the stepped piston assembly has an auxiliary piston located between the large piston and the small piston which auxiliary piston is mechanically linked to the large piston and which is reciprocable in an auxiliary cylinder, and wherein there is provided a valve through which fluid can flow from the volume enclosed by the large cylinder forward of the large piston into the volume enclosed by the auxiliary cylinder rearward of the auxiliary piston.

Abstract: A demolition tool for breaking solid materials, particularly rock or concrete in tunnelling, mining, demolishing and excavating applications. The tool has a single impactor (1) of the projectile type which is driven by high pressure liquid towards the material to be broken. A gas pressure accumulator (2) is included for storing high pressure energy. This energy is transferred at a high rate through short, wide and streamlined channel means (8, 13, 57, 9), having high capacity and low flow losses, to the impactor (1). Valve means (7) is provided in the channel means so that the accumulator (2) can be recharged during the return stroke of the impactor, giving a high repetition rate. A low pressure annular accumulator (5) drives the impactor during the return stroke.

Abstract: In a device such as a refrigerant compressor provided with a reciprocating piston having a stroke length which can be changed from one value to another in accordance with the direction of rotation of the crankshaft driving a connecting rod, there is provided an arrangement in which the top deadcenter position of the piston can be maintained irrespective of the changes in stroke length by an eccentric ring which has limited rotation on the crankshaft crankpin, and a second eccentric ring encompassing the first eccentric ring and which has limited rotation relative to the encompassing strap end of the connecting rod. With this arrangement, both the throw of the crankpin means and the effective length of the connecting rod are generally concurrently changed inversely when the crankshaft rotates in one direction or alternatively in the other direction.

Abstract: The use of the air-spring in automatically retracting (or extending) an air cylinder after it was extended (or retracted) by the air pressure supplied from the compressed air line is disclosed.

Abstract: A valve actuator includes a hydraulic cylinder with a pair of pistons separately, slidably mounted therein for movement between a first end and a second end of the cylinder. An actuator rod is joined to a first of the pistons to extend through an opening in the first end of the cylinder to terminate exterior thereto and be capable of being joined to a valve stem. A high pressure gas accumulator is mounted on the cylinder to locate the second end thereof within the accumulator. The second end of the cylinder has an end closure with access therethrough to allow communication between the interior of the accumulator and a first side of the second piston of the pair. Normally, hydraulic oil is supplied to the cylinder to act on the first piston thereby causing both pistons to move axially against the high pressure gas of the accumulator which, in turn, axially moves the pistons when the hydraulic fluid is discharged.

Abstract: The hydraulic spring comprises a fixed part innerly provided with an axial bore communicating with a reservoir of liquid and having an outlet aperture, a moving part filled with liquid, surrounding the fixed part and provided with an inside recess. The inside recess of the moving part is substantially in front of the outlet aperture of the fixed part at position of outer dead center and substantially in front of the free end of the fixed part at position of inner dead center.

Abstract: A valve actuator is capable of being mounted on a valve in alignment with a valve stem which can be moved to open and close the valve. The actuator includes a hydraulic cylinder and a piston slidably mounted within the cylinder. A piston rod is joined at a first side of the piston and extends outwardly of the cylinder toward the valve to be joined to the valve stem. A high pressure gas accumulator is mounted on the cylinder and includes a generally spherical shaped pressure wall which is intersected by the cylinder to locate an end of the cylinder within the accumulator to allow communication of the interior of the accumulator with a second side of the piston. Hydraulic oil acting on the first side of the piston opens the valve against high pressure gas within the accumulator and evacuation of the hydraulic oil allows the high pressure gas to act on the second side of the piston to rapidly close the valve.

Abstract: A positive displacement pump for metering liquid chemicals and applying such chemicals into grains such as seed being conveyed through a screw conveyor, the pump including a reciprocating rod operated by an eccentric cam on the screw conveyor shaft, the pump rod having a shoulder and a stop carried by the housing to limit the length of movement of the rod, the stop being a rotary cam having flat surfaces, of varied distances from the cam axis and controlled by a hand operated knob.

Abstract: An actuator is provided which is respondable to control fluid pressure for moving an operative means of a valve between open and closed positions. The actuator comprises a housing defining a cylindrical bore therewithin. In one form, a shaft is carried in the housing and is engagable with the operative means. Means define first and second effective piston areas and are carried by one of the shaft and the housing and are sealingly slidable along the other of the shaft and the housing, being longitudinally movable within the cylindrical bore. The apparatus has first and second fluid chambers companionly associated with the means defining the first and second effective piston areas within the bore for yielding a differential force across the means defining the first and second effective piston areas upon increase of fluid control pressure within the actuator.

Abstract: Device for a hydraulically driven percussion hammer for activating a tool, comprising a differential piston with corresponding cylinder, where the piston's largest surface is closest to the percussion tool, and where the smallest working surface is in direct hydraulic connection with an air tank. The largest working surface is above a multiple valve in connection with a hydraulic pressure medium. The valve is adjustable from an admission position with closed return duct to a position where the admission is blocked and the return duct is open. The piston chamber above the piston's small working surface has a feed duct with back pressure valve for a hydraulic pressure medium.

Abstract: A column including a cylinder, a piston axially slidable in the cylinder cavity, a piston rod axially projecting from the cylinder, and a valve permitting selective communication between the two compartments of the cylinder cavity separated by the piston for flow of fluid between the compartments is additionally provided with a helical compression spring coiled about the piston rod and impeding axial movement of the piston on the piston rod in one direction, movement in the other direction being limited by a radial abutment flange on the piston rod. The spring favorably affects the comfort of a chair whose seat is mounted on the column.

Abstract: The upper edge of a cup-shape flexible diaphragm in the lower part of a vertical dispensing cylinder is sealed to the side of the cylinder, with the bottom of the diaphragm engageable with the bottom of the cylinder around an inlet and outlet port to close it. The bottom wall of the diaphragm may have a central thickened portion for engaging the bottom wall of the cylinder, with the rest of the diaphragm bottom spaced from the cylinder bottom wall. Engaging the side wall of the cylinder above the diaphragm is a piston having a lower portion filling the diaphragm cup and attached to its bottom wall. The diaphragm and piston are movable upwardly in the cylinder by liquid product forced up through the cylinder port, and the upper part of the cylinder has an inlet for air to move the piston and diaphragm downwardly to expel liquid product from the cylinder.

Abstract: A digital positioner for remote actuation of a control valve includes a double-acting actuating piston connected to the control valve and a plurality of fluid-responsive stop means disposed to either side of the actuating piston. A plurality of remotely controlled pilot valves are operatively connected to respectively control the actuating piston and selected ones of the stop means. The system is especially adapted for remotely controlling hydraulic systems having a control valve for modulated control of the system for different speeds of the system.

Abstract: A hammer and more particularly a fluid operable hammer wherein alternating impetus provided by pressurized liquid and gas means actuates a reciprocable hammer piston to generate repetitive impact loads.

Abstract: A new heat engine in which liquid moves in a tube, one end of which is closed. The tube is heated at the closed end, and the liquid oscillates along the length of the tube. When the liquid interface enters the hot section, some of the interface vaporizes, so that the pressure in the space between the interface and the end of the tube increases, and the interface is forced back into the cooler section of the tube. The vapor then condenses, the pressure falls, and the liquid moves back toward the hot end.The longer the tube in relation to size of the hot section or "boiler," the greater the momentum of the liquid when it enters the boiler, and the higher the peak pressure ratio which is developed. High pressure ratios are essential for efficient operation. It is also generally necessary for the boiler walls to be heavy enough to "store" the heat required for one complete cycle, and to be able to reject it to the water during the very short time that the interface is within the boiler.

Abstract: In a liquid product measuring pump driven by an air motor having air valve controls for reversing the reciprocating motion of the air motor at the end of the stroke for controlling the liquid product measuring, an adjustable stop assembly including a quickly replaceable stop bar with an extendible threaded rod therein, the rod being minutely adjustable by an insert fitting on the mounting for the stop bar.

Abstract: In a percussion tool a means is provided for delaying the manifestation, on a valve means sensitive to such change in pressure, of a change in pressure of the fluid applied to the hammer piston at one end thereof and which drives such hammer piston in its working stroke, the valve means being that means which serves to control the inlet and exhaust parts of the fluid circuit which applies pressure to the other end of the piston.

Abstract: An operating and shock cylinder assembly for vehicle mounted underbody scraper and grader blades, plows and the like. The assembly of cylinders operates with hydraulic fluid and air, both under pressure, to move the blade or plow between retracted and road engaging positions. It also permits the blade to trip or yield when it engages a fixed obstacle in the road after which the blade quickly returns to its road engaging position. The assembly includes a pair of coacting cylinders which are first charged with air under pressure after which one of the cylinders is charged with hydraulic fluid under pressure. The hydraulic charge forces all of the air into the other cylinder and further compresses it, and this air operates as a powerful spring force or load on a piston in the cylinder that is connected to the pivotally mounted blade. Under this condition, the blade is firmly but yieldably biased into road engaging position.

Abstract: A hydraulic impact device has a hammer member carrying a piston which is reciprocally disposed in a cylinder chamber to form an expansible chamber. When the expansible chamber is pressurized, the hammer is retracted against an air spring or other energy storage device by the high pressure. A sleeve valve is reciprocally disposed in the cylinder chamber between the piston and the energy storage device and is held against the piston by an imbalanced fluid pressure as the hammer is retracted against the spring. When the piston and sleeve valve have been retracted to a predetermined position, high pressure fluid is ported between the sleeve valve and piston to hydraulically separate the two members.

Abstract: A hammer and more particularly a fluid operable hammer wherein alternating impetus provided by pressurized liquid and gas means actuates a reciprocable hammer piston to generate repetitive impact loads.