Showing papers on "Piston published in 1986"

Pneumatic meat saw

Abstract: A pneumatic meat saw including an on-off valve which is actuated to allow air flow to either side of a disk in a shuttle valve. The shuttle valve controls the flow of air to opposite sides of a piston which is operatively connected to a drive shaft which has the saw blade secured thereto. The shuttle valve causes the piston to be reciprocated which in turn causes the saw blade to be reciprocated.

Cap, reservoir and dropper assembly for bottles

Abstract: The cap reservoir and dropper assembly for bottles includes a reservoir (1) fitted with a collar 913) adapted for resting on the mouth of a bottle (4), a delivery piston (2) the lower part of which is shaped like a flute mouthpiece (24) and the upper part of which is shaped like a collar (22). The assembly further includes a cap (3) the lower part of which is in the form of a removable strip (33). The delivery piston is equipped in its upper part with a dropper (23). The cap may be equipped with a feature which cooperates with the delivery piston collar to push the delivery piston downwards.

Float type wave energy extraction apparatus and method

Abstract: An apparatus and method of obtaining useful energy from wave action in a body of water. The apparatus comprises a cylinder, a reciprocal piston in the cylinder, a piston rod connected to the piston and extending sealably out of the cylinder, a mechanical tensioning device connected between the piston and the cylinder for maintaining resilient tension between the piston and the cylinder, a float connected to one of the piston rod or the cylinder, an anchor flexibly connected to the other of the piston rod or the cylinder which is not connected to the float, an inlet check valve and an outlet check valve connected to the cylinder, and a conduit extending from the outlet check to an area where water may be usefully employed. The mechanical tensioning device may be a spring or a weight and tether. The apparatus and method may be used to operate a hydroelectric generator.

Method and apparatus for dispensing viscous materials

Abstract: An apparatus (28) for dispensing solder paste into openings (26-26) in a stencil (24) comprises a housing (30) having a piston (60) slidably mounted therein. A manifold (70), having a successively increasing cross-sectional area, is attached to a side wall (42) of the housing for admitting a viscous material, such as solder paste therein through successively larger sized openings (76-76) so the paste is distributed evenly beneath the piston. A pair of elastomeric blades (50-50) are secured to, and depend from the housing on opposite sides of a slot (46) to contact the stencil (24). Upon the application of a fluid pressure against the piston, paste will be expelled from the slot within a working region (96) between the blades. The blades force paste into the openings in the stencil when the housing is moved thereacross.

Dispensing device for storing and applying at least one liquid or pasty substance

Abstract: A dispensing device comprises a cartridge unit with at least two chambers containing liquid or pasty substances and pistons therein being connected with each other by at least one blade adapted for cutting through a dividing wall, between two chambers and separating their contents, only one piston assembly being required which can be operated with a propellant under excess pressure preferably not exceeding 6 bars. As no piston rod is required the construction of the device is very compact. In a first step for actuating the pistons, the cartridge unit is moved forward toward an exit end of the device bearing a discharge nozzle whereby valves in the device are opened and contents from the cartridge unit are conveyed to the discharge nozzle. After each discharge a restoring element returns the cartridge unit to a rearward end position whereby the valves are closed and no contents can leak from the cartridge.

Diverter system and blowout preventer

Abstract: A system is disclosed which may alternatively be used as a diverter or as a blowout preventer for a drilling rig. The system comprises a blowout preventer attached above a spool having a hydraulically driven sleeve/piston. An outlet flow passage in the spool, which may be connected to a vent line, is closed off by the sleeve wall when the spool piston is at rest. Hydraulic ports are connected above and below the blowout preventer annular piston and above and below the spool annular piston. The ports below the blowout preventer piston and above the spool piston are in fluid communication with each other. A hydraulic circuit is provided having two valves between a source of pressurized hydraulic fluid and a drain.

Oxygen enriched reciprocating piston respirator.

Abstract: A variable flow reciprocating piston respirator system which is capable of providing a substantially constant oxygen enrichment over an entire inspiration stroke of a variable flow respirator output. A proportional control valve is used to deliver oxygen from an oxygen supply tank to the output of a reciprocation piston pump. A microprocessor controls the magnitude of opening of the proportional valve to insure that a proper overall volume of the output is produced with the proper percentage of enrichment of oxygen.

Pipette and pipetting apparatus

Abstract: A pipette includes a pipette body made of plastic material and a pipette piston made of plastic material that is also electrically conductive. The pipette is automatically received or discarded in a pickup device which has an electric transmission filament.

Positive displacement hydraulic-drive reciprocating compressor

Abstract: The invention disclosed relates to the art field embracing positive displacement reciprocating compressors of the type featuring hydraulic drive, and sets out to simplify the construction of such units, rendering them more functional at the same time. Four coaxial bulkheads (1, 2, 3, 4) are adopted, set apart one from the next by three cylinder barrels (5, 6, 7) and three pistons (8, 9, 10) which are mounted to a common rod (11) and reciprocated thus, each in its respective barrel; the central piston (9) and barrel (6) are of either greater or smaller diameter than the remainder. Hydraulic oil from a power pack driving the compressor flows alternately into chambers (14, 15) which are occupied by the rod (11), and bounded at one end by one of the pistons (8, 10) of smaller or greater diameter.

Servo control system for a reciprocating piston respirator

Abstract: A control system (10) for moving a piston in a reciprocating piston respirator (46) which utilizes predictive servo control techniques. The present invention uses nonlinear time domain analysis rather than linear frequency domain analysis to produce a predictive servo control system (10) for precisely controlling the movement of a piston in a reciprocating piston respirator (48). A plurality of flow profiles can be produced using stored factor tables. Current pressure and position information are used in the predictive servo control system (10).

Latching and sealing device

Abstract: A latching and sealing device suitable for use as a cover seal for a plunger or piston in a syringe or plunger pump includes a cylindrical seal member having a body portion and lip-and-latch means for both sealably engaging a surrounding surface and latching to the piston. A spring disposed in between the lip-and-latch means and the piston provide a constant sealing pressure while allowing the piston and seal member to be moved within a bore. Sealing between the lip-and-latch means and the bore is enhanced by use of a berm and notches radially aligned with the biasing spring.

Reciprocating-piston internal combustion engine

Abstract: A reciprocating-piston internal combustion engine has a drive-unit block 1 which consists of cylinders, cylinder heads, pistons, connecting rods, a crankshaft and its bearings. This drive-unit block 1 is mounted, insulated against solid-borne sound, in an external trough 2. Between the drive-unit block 1 and the upper edge of the external trough 2 is seated an elastically flexible force- free oil seal 5 surrounding the drive-unit block 1 in a frame-like manner. The oil seal 5 engages, in the region of the upper edge of the external trough 2, with pressed- in webs 7, into grooves 3, 4, 5, 6 which are arranged, on the one hand, in the drive-unit block 1 and, on the other hand, in the wall 2a of the external trough. In order to ensure that the oil seal performs its function for long periods of time in spite of pronounced relative movement of the drive-unit block 1 and of the external trough 2, the webs 6, 7 of the frame-like oil seal 5 are connected by means of a thin-walled bulged-out concertina 8. This concertina 8 has in each case, at the transitions of adjacent frame legs, a wave-like depression 11 running from one frame leg to the other.

Safety blood sample apparatus

Abstract: A sterile barrel and piston assembly with attached aspirating needle is delivered ready for use. Following removal of a needle shield and a reversible safety cap from the rear of the piston, the needle is inserted in a vein and evacuated blood sample tube is inserted in the piston to be penetrated by the rear end of the needle. Following removal of the needle from the vein and removal of the evacuated tube now containing a blood sample, the piston is turned in one direction relative to the barrel of the device to release a first lock between the barrel and piston, followed by retraction of the piston and turning of the piston in the same direction to activate a second lock between the barrel and piston. The safety cap is reversed and re-applied to the rear of the piston where it becomes permanently locked in place. The needle is now safely enclosed within the barrel rearwardly of a safety shield and membrane on the front of the barrel. The non-reusable device is now disposed of according to acceptable practice.

Apparatus for controlling a pump to account for compressibility of liquids in obtaining steady flow

Abstract: There is disclosed herein an apparatus and method for controlling a dual piston pump for a liquid chromatography system so as to pump a flow of solvent through the liquid chromatography column at a constant flow rate and with a solvent composition which is substantially equal to the desired solvent composition despite changing conditions of compressibility of the solvent. The control system uses a computer which measures the time it takes the pump shaft to move through an overlap region in the pump cycle when both pistons are simultaneously pumping as normalized to the time taken by the pump to move through a constant velocity portion of the piston travel defined by the user. This time is compared to the time stored in the computer for the particular flow rate used to measure the time defined above for the pump to move through the overlap region for an incompressible solvent at low pressure as normalized to the time taken by the input piston to move through the same user defined segment of the constant velocity portion of the travel of the input piston. The ratio of these two times is then used in an algorithm to derive a correction factor for compressibility. This correction factor is then used to control the flow rate and the makeup of the solvent composition to maintain the correct values over changing conditions of solvent compressibility.

Apparatus for setting a high temperature packer

Abstract: Apparatus for sealing a well bore annulus. A mandrel includes non-elastomeric packer elements disposed thereabout. A first annular piston is received about the mandrel and is slidable upwardly against the packer elements to seal the same in a well bore. A bi-directional slip assembly is disposed about the lower portion of the mandrel and a second annular piston is slidable along the mandrel above the slip assembly for setting the same in response to downward piston action. The mandrel includes a pair of bores for communicating internal mandrel pressure to both pistons. An increase in mandrel pressure causes the first piston to move upwardly thereby sealing the packer elements in the bore and causes the second piston to move downwardly thereby setting the slips.

Method and apparatus for controlling spring stiffness, in particular in vehicles

Abstract: A method and an apparatus for controlling the spring stiffness in two bodies or masses that are movable relative to one another and in their absolute positions with variable speeds, in particular in resilient wheel suspension systems for vehicles and the like, wherein the volume positively displaced by a piston in a cylinder pressure chamber can be abruptly switched over into two partial volumes in accordance with load, movement and operating parameters of the vehicle, suspension and wheel as well as vehicle body, with it being possible, with partial volumes communicating with one another, to perform an additional total-volume fine adjustment continuously via a cylinder/piston unit and also in accordance with the parameters mentioned. A suspension concept of this kind, with slow, continuous adaptive adaptation and rapid switchover to greater stiffnesses is augmented by an asymmetrically variable damping and a preferably fast-operating level control means.

Adjustable hydraulic vibration damper

Abstract: Hydraulic adjustable vibration damper with a damping piston, which divides the work cylinder into two chamber halves, whereby the two chamber halves are connected with one another by a bypass, in which an electromagnet controls the bypass. The bypass valve located in the bypass includes an axially-movable valve body which works together with a passage and which is controlled by the adjustment apparatus, and at least one spring-loaded valve which operates as a function of the pressure connected in series with the valve body.

Hydraulic safety barrier traffic-way controller

Abstract: A vehicle traffic-way controller of retractile barrier configuration wherein activation and control is by hydraulics in the form of a pressure source applied from a motor driven pump and directed by a valve to opposite ends of a double acting cylinder and piston actuator to extend and retract the barrier, there being switch control with positive positioning of the barrier and with impact absorbing protection for the hydraulics and structure.

Apparatus and method for a balanced internal combustion engine coupled to a drive shaft

Abstract: An internal combustion engine is described in which the piston movement is parallel to the drive shaft. The engine cylinders are arranged in opposed pairs and the piston rods directly coupled so that the power stroke in one cylinder can assist with the compression stroke in the associated cylinder. The coupled or common piston rods have attached thereto a carriage that engages in a cam groove in the drive shaft. The drive shaft cam groove receives the force of the carriage as it is propelled by the pistons and the resulting torque causes a rotation of the drive shaft. The cylinders include a precompression chamber that assists in the exchange of combustion products with air. The internal combustion engine does not require special cooling and does not require a starter motor.

Measuring valve for dosing liquids or gases

Abstract: A metering valve includes a piezoelectric cylinder connected via a spring biased needle to a valving element for closing a metering opening. To compensate for slow changes in the length of the piezoelectric control member, there is provided a damping piston connected axially to the piezoelectric member and being movable in a well formed in the valve housing and defining with the end face of the piston a damping chamber. A tubular membrane surrounds a portion of the damping piston and is attached to the piezoelectric member and to an inner wall of the housing around the opening of the well to define with the piston an annular equalizing space. The damping and equalizing spaces are filled with liquid and communicate with one another via a narrow throttling gap formed between facing walls of the well and of the piston.

Hydraulic master cylinder assembly

Abstract: This invention relates to hydraulic master cylinder assemblies comprising a hydraulic master cylinder (11) and an actuating mechanism therefor and in particular to a hydraulic master cylinder assemblies in which it is possible to alter the travel ratio between a driver operable actuating lever (14) and a piston (16) of the hydraulic master cylinder (11).The actuating mechanism includes a lever mechanism (15, 47) interposed between the actuator lever (14) and the piston (16) the effective lever arm length of which can be altered by means of an adjustable abutment member (47) forming part of the mechanism (15, 47).

Fuel injection nozzle

Abstract: PURPOSE:To increase the valve opening pressure as the fuel pressure increases by urging the edge part of a spring for urging a nozzle needle in the valve opening direction by a piston in a pressure chamber, in a fuel injection nozzle for Diesel engine. CONSTITUTION:In unloaded state, the residual pressure between each injection is low, and also the pressure in a pressure chamber 12 which is determined according to the sum of the residual pressure and the pressure after the pass through an orifice 10 is low, and increasing the set pressure of a spring 20 by operating a piston 14 is impossible, and the valve opening pressure of a fuel injection nozzle A is low. When a load increases, the fuel injection quantity increases to increase the residual pressure, and also the pressure in the pressure chamber 12 is increased by the sum with the fuel pressure after the passing through the orifice 10, and the spring 20 is compressed against its set load by the piston 14, and the valve opening pressure is increased by increasing the set load of the spring 20. Therefore, the engine noise in idling can be reduced, and the reduction of white smoke in exhaust gas and THC and the high output in high loading can be made compatible.

Apparatus for fast determination of the rheological properties of thermoplastics

Abstract: Apparatus composed of a control and monitoring unit 1, a thermostated cylinder 2 receiving a measured quantity of material to be evaluated, a plunger 3 sliding in the cylinder 2, an exchanger system enabling the cylinder 2 to be equipped with a suitable die 6 for the measurement to be carried out, a stepping-control motor 7 ensuring a monitored travel of the plunger 3, a force-sensor 9 yielding a signal as a function of the force applied to the plunger 3, and an electronic microprocessor system monitoring the stepping motor 7 as a function of the position of the piston and/or of the signal emitted by the force-sensor 9 at the end of the time assigned to the thermal conditioning of the measured quantity to be evaluated, the plunger 3 is situated at a distance from the die 6 permitting the measurement and acts for 10 to 180 seconds on the measured quantity according to a parameter of the speed of travel of the plunger or of the applied force specified by the measurement to be carried out.

Cam-controlled self-contained internal combustion fastener driving tool

Abstract: A fastener driving tool powered by internal combustion of an air/fuel mixture. The tool body contains connected upper and lower coaxial cylinders. The upper cylinder is provided with a piston assembly and is connected by a one-way valve to a combustion air chamber. The lower cylinder contains a piston/driver assembly and is surrounded by and connected to a return air chamber. The upper cylinder piston assembly and the lower cylinder piston/driver assembly, when in their normal unactuated positions, define therebetween a combustion chamber provided with an ignition device. A positive trigger-actuated cam system, upon actuation of the trigger, is configured to open a fuel valve to introduce a measured amount of gaseous fuel from a source thereof into the combustion chamber; to thereafter open an air valve to introduce a measured quantity of air from the combustion air chamber into the combustion chamber; to next actuate the ignition device to combust the aire fuel mixture causing the lower cylinder piston/driver assembly to drive a fastener and to fill the return air chamber with air under pressure in the upper cylinder piston assembly to replenish air under pressure in the combustion air chamber; and finally to actuate a control valve operating an exhaust valve eliminating products of combustion enabling the upper cylinder piston assembly to return to its normal position and air from the return air chamber to return the lower cylinder piston/driver assembly to its normal position.

Piston type compressor with improved suction reed valve stopper

Abstract: A piston type compressor having a cylinder block in which a plurality of compression chambers permit a plurality of pistons to be reciprocated so as to compress a refrigerant sucked from a suction chamber formed in an end housing into the compression chambers through suction ports of a valve plate openably closed by a plurality of suction reed valves. The compressor also has a valve stop construction for stopping the movement of the suction reed valves when the valves reach the opening position thereof apart from the valve plate. The valve stop construction includes recessed seats formed in an axial end face of the cylinder block so as to permit a portion of the free end of respective suction reed valves to be first seated on the recessed seats, and to permit the remaining portion of the free end of the suction reed valves to be stably seated on the recessed seats. The gradual stoppage of the suction reed valves suppresses vibration of the valves and prevents noise.

Positively controller automotive suspension system

Abstract: A positively controlled automotive suspension system provides both of driving stability and riding comfort by adjusting damping characteristics of the suspension system according to the driving condition. The suspension system is soften in response to bounding and rebounding shock for effectively absorbing road shock. On the other hand, in response to relative displacement of the vehicle body and road wheel assembly, the suspension system serves for regulating the relative distance and whereby provides sufficient driving stability. The system comprises a hollow cylinder defining a chamber, a piston thrustingly received within the chamber of the cylinder and defining therein a first and second fluid chambers, both filled with a working fluid the piston being free to move axially with the chamber, a fluid pressure source, a hydraulic circuit connecting the first and second fluid chamber and the fluid pressure source, a pressure control valve disposed within the hydraulic circuit and adapted to selectively establish and block fluid communication between the first and second fluid chamber and the fluid pressure source, means, responsive to relative displacement between a vehicle body and road wheel assembly out of a predetermined normal range, for controlling the pressure control valve so as to adjust the fluid pressure in the first and second fluid chambers in order to adjust the relative distance between the vehicle body and the road wheel assembly back to within the predetermined normal range, and means, responsive to bounding and rebounding motion of the road wheel relative to the vehicle body, for controlling the pressure control valve so as to adjust the fluid pressure in the first and second fluid chambers to assist smooth displacement of the piston within the cylinder thereby absorbing bounding and rebounding energy which would otherwise be transmitted to the vehicle body.

Digitally controlled air-over-hydraulic actuator and method

Abstract: A digitally controlled air-over-hydraulic actuator includes a pneumatic cylinder and a hydraulic cylinder each having a separate piston and a common connecting rod. The pneumatic piston applies force to the connecting rod urging movement of the hydraulic piston. Bleeding of oil from one side of the hydraulic piston to the other is controlled by means of digital pulses applied to a digital valve that allows oil on either side of the hydraulic piston to flow to the other. The digital valve includes a moving piston having an oil passage that is momentarily aligned with ports to opposite sides of the hydraulic cylinder. A control system senses the differential pressure between opposite sides of the pneumatic piston to produce pulses that accelerate the digital valve piston past the ports, precisely controlling forced movement of the hydraulic piston.

Liquid dosing device with digital display

Abstract: A liquid dispenser has a cylinder in which a piston may move in an intake stroke and a discharge stroke. A pulse generator responds to any movement of the piston in the discharge direction, whereby a counting and readout device provides a dispensing measurement readout even for inadvertent discharge movements of the piston. Movement of the piston in the discharge direction rotates a wheel in the pulse generator. A ratchet system may be provided to prevent rotation of the wheel in reverse during intake movements of the piston. Alternatively the wheel rotates in both directions, and a discriminator is provided to discriminate between the two directions of movement.

Tensioner for toothed drive belts

Abstract: A tensioner for toothed belts comprises a hydraulic fluid filled cylinder having a piston with a rod projecting out of the cylinder and engaging a pivoted arm with a roller at one end for engaging the belt. A spring within the cylinder urges the rod in the projecting direction, and a check valve carried by the piston allows the rod to project rapidly to take up slack in the belt. Hydraulic fluid, however, flows through the small clearance between the piston and the cylinder wall as the rod retracts, and therefore limits the rate of retraction. A path is provided between seals surrounding the rod to route air directly to the reservoir so that it does not enter the fluid chambers within the cylinder. The piston material is chosen to expand more rapidly than the cylinder with increasing temperatures to reduce variations in leak-down time.

A Multidimensional Model Prediction of Heat Transfer in Non-Fired Engines

Abstract: An axisymmetric three-dimensional model for in-cylinder processes has been applied to the predictions of wall heat transfer in a non-fired engine cylinder. Computed heat fluxes are shown for combustion chambers with a flat piston and a deep-bowl piston for swirl and non-swirl cases. The predictions compare well with existing experimental heat fluxes at several different radii on a cylinder head except in a central part. It is also shown that the predictions of surface-averaged heat flux are consistent with those obtained from empirical correlations. The effect of compression-expansion work is indicated by predicted temperature profiles and typically demonstrated by phase difference between the heat flux and the bulk-mean gas temperature. Computational discussions are given on local heat fluxes in the deep-bowl-piston combustion chamber and suggest that local heat fluxes are greatly increased by squish motion, squish-induced vortex, and swirling motion spun-up in the bowl.