Showing papers on "Piston published in 1982"

Medication infusion pump

Abstract: An extracorporeal medication infusion device provides a precise infusion rate of a liquid medication into a human or animal body. The infusion device includes a permanent portion which has a case, a battery, a programmable electronic controller, and an electromagnetic solenoid core and solenoid coil for providing an actuation force. The infusion device also includes a disposable portion which includes a reservoir filled with a liquid medication that is to be dispensed and a pump for pumping the medication from the reservoir into the user's body. The pump includes a pump chamber and a piston connected to an electromagnetic armature for altering the volume of the pump chamber in response to the actuation force.

Optimal paths for thermodynamic systems: The ideal diesel cycle

Abstract: We apply the method of optimal control theory to determine the optimal piston trajectory for successively less idealized models of the Otto cycle. The optimal path has significantly smaller losses from friction and heat leaks than the path with conventional piston motion and the same loss parameters. The resulting increases in efficiency are of the order of 10%.

Computer optimized adaptive suspension system having combined shock absorber/air spring unit

Abstract: A vehicle suspension system in which a computer controls damping and spring forces to optimize ride and handling characteristics under a wide range of driving conditions. A combined shock absorber/air spring unit is connected between the wheel and frame of a vehicle. The shock absorber includes a hydraulic sensor which provides signals to the computer which are representative of the position of the piston within the shock absorber. The computer utilizes these signals to control compression and rebound hydraulic pressure regulators to produce preprogrammed compression and rebound damping forces that will yield the desired ride and handling. The air spring may be connected in series with the shock absorber for compression and rebound along the same axis. Pressure sensors and air pressure inlet and outlet valves are connected to the computer for adjusting the pressure within the air spring to provide the desired spring rate.

Hybrid drive arrangement

Abstract: A hybrid drive arrangement for vehicles, in particular motor vehicles, has an electric machine (2) which can be fed from an electric energy store (7), if appropriate feeds back into it and is connected via a first switchable coupling (5) to a transmission (3) which drives at least one drive axle (6) of the vehicle and via a second switchable coupling (4) to a reciprocating piston internal combustion engine (1) which is connected in series to the electric machine. Here, the crankshaft of the reciprocating piston internal combustion engine is constructed without a flywheel and the flywheel mass which is required for compensating the unequal rotary force diagram of the reciprocating piston internal combustion engine (1) is essentially integrated into the rotor part (26) of the electric machine (2). According to the invention, the electric machine (2) also has an outer field component (27) which is held rotatably with respect to the fixed housing (35) and to the inner rotary component (26) which is mechanically connected to the couplings (4, 5), receives the field windings, and can be fixed to the fixed housing (35) by means of a brake device (28).

Fluid collection device with phase partitioning means

Abstract: A blood collection device for collecting and separating whole blood into its relatively low and high density phases includes a collection container, and a housing having an enlongate passageway in the housing. Gel-like material having a specific gravity intermediate the specific gravities of the separated high and low density phases is disposed in the passageway. A piston having a specific gravity greater than that of the gel-like material is disposed in the passageway and sized to allow gel-like material to flow past it at a low flow rate and to retard the movement of the piston during centrifugation of the device. Means for preventing the flow of the gel-like material from the housing and toward the interface of the phases until the piston has moved out of the passageway is provided.

Two-dose syringe

Abstract: A syringe for delivering two separated bodies of fluid comprising: a first piston for separating the two bodies of fluid; a second piston for pushing the two bodies of fluid out of the syringe; and a fluid chamber having a no-pass zone in which the pistons can slide and which has a cross section that each of the pistons substantially fills, preventing the passing of fluid around the pistons when they are in the no-pass zone, an output zone to direct fluid pushed out of the syringe by the pistons, and a bypass zone, for receiving the first piston, which connects the no-pass and output zones and which has a cross section that the first piston is unable to fill, so that when the first piston enters the bypass zone the fluid between the first and second pistons can pass around the first piston to the output zone. In a preferred embodiment the bypass zone has ridges projecting in from its wall, which push portions of the first piston away from that wall, allowing fluid to flow around the first piston; the output portion forms a nozzle designed to fit into, and make a seal with, a urethra; and the two bodies of fluid are a lubricating antiseptic and a lubricating anesthetic for use in preparing a patient for catheterization.

Finite time thermodynamics: Optimal expansion of a heated working fluid

Abstract: We determine the solution to the prototype problem: Given a finite amount of time, what is the optimal motion of a piston fitted to a cylinder containing a gas pumped with a given heating rate and coupled to a heat bath? The optimal motion is such as to maximize the work obtained via the piston in a specified period of time. This problem is solved for various end‐point constraints, including constraints on final volume, final energy, or final volume and energy. We consider several associated problems including constraints on the rate of change of volume, piston friction, piston mass, and inertial effects of the gas. Explicit thermodynamic analyses of the solutions are carried out for various examples. The efficiency and the gain over nonoptimal paths are studied. Significant improvement over the bound on the efficiency is obtained as calculated by (infinite time, reversible) thermodynamics. The nature of the limit of the optimal solution as the time approaches infinity is determined. For a finite heating ...

Electromagnetic reciprocating pump and motor means

Abstract: An electromagnetic reciprocating motor or pump for use for providing mechanical force for actuation of other fluids or components, and includes a cylinder provided with closures at each end, at least a pair of electromagnets operatively associated with the cylinder, and surrounding the same, a magnetically responsive piston provided within the cylinder and capable of longitudinal shifting reciprocally within the cylinder upon the sequential energization of the electromagnets, and either a mechanical actuator or electronic triggering components cooperating with electrical circuitry and connecting with the electromagnets which upon energization charging the electromagnets in timed sequence for inducing their reciprocal shifting of the piston within the cylinder means Electrical circuitry includes a power supply, a sequencing circuitry, coil driver circuitry, all of which upon their cooperative functioning provide for a regulating the rate, timing, and quantity of charge delivered to each of the particular electromagnets during operation of the reciprocating device

Device for dispensing measured amounts of multi-component materials

Abstract: A manually operable device is provided for dispensing measured amounts of a mastic-like or paste-like multi-component material. The components are supplied in separate containers and each container has an axially displaceable ejection piston. The pistons are displaced by piston rods and each piston rod can be gripped by a clamping jaw and the jaw is displaced via a manually operated lever and a stirrup. A support bearing member affords lateral support for the piston rods and the clamping jaws are pivotally mounted on the bearing member. The drive for the piston rods acts through the clamping jaw and the support bearing member so that each rod is displaced axially and does not need to be connected to the other. Due to a symmetrical arrangement of the forces acting on the support bearing member, the forces cancel one another out.

Stirling cycle cryogenic cooler

Abstract: A long lifetime Stirling cycle cryogenic cooler particularly adapted for space applications comprised of a compressor section (10) centrally aligned end to end with an expansion section (12) and respectively including a reciprocating compressor piston (14) and displacer (16) radially suspended in interconnecting cylindrical housings (18, 20) by active magnetic bearings (26, 28, 30, 32) and having adjacent reduced clearance regions (82, 84, 108) so as to be in non-contacting relationship therewith and wherein one or more of these regions operate as clearance seals. The piston (14) and displacer (16) are reciprocated in their housings (18, 20) by linear drive motors (48, 52) to vary the volume of respectively adjacent compression and expansion spaces (44, 46) which contain a gaseous working fluid and a thermal regenerator (95) to effect Stirling cycle cryogenic cooling. Electrical circuit means (140, 142) are additionally included for energizing the magnetic bearings (26, 28, 30, 32) and for controlling the stroke amplitudes and relative phase angle between the compressor piston (14) and displacer (16) during the cooling cycle.

Annular blowout preventer

Abstract: An annular blowout preventer having a body with a central bore, a piston chamber, and a packer chamber surrounding the central bore, a piston in the piston chamber, an annular packer in the packer chamber, the annular packer including a resilient annulus and a plurality of metal irising inserts embedded in the annulus and having upper triangular plates, lower triangular plates, a stem connecting the plates and means interconnecting adjoining plates to avoid inadvertent separation of one or more of said inserts, the annular packer moving between open and closed positions responsive to movement of the piston.

Reciprocatory piston and cylinder machine

Abstract: A reciprocatory piston and cylinder machine particularly suitable for use as a vacuum pump includes a cylinder (17), a cylindrical piston (16) relatively slidably reciprocable within the cylinder (17), and means for substantially sealing the annular space between the piston (16) and cylinder (17) in lieu of oil or other liquid lubricant. The sealing means comprises a sleeve (102) of a low-friction material disposed under circumferential tension, and preferably also under longitudinal tension, on the cylindrical surface of the piston (16). Also disclosed is a reciprocatory differential piston and cylinder machine of particular prior construction having a one-way valve (42) in an exhaust port (30) ahead of a head portion (24) of the piston (16). The arrangement is such that, as the front face (28) of the piston head portion (24) approaches the cylinder end face (52), the front face (28) physically moves the one-way valve (42) so as to open the exhaust port (30).

Automotive vehicle suspension

Abstract: An automotive vehicle suspension comprising a beam, and an air spring between the vehicle frames and the beam. The air spring comprises an air spring lobe connected to the vehicle frame and a reinforced piston mounted on the beam in laterally offset relation to the longitudinal centerline of the beam.

Optimization of a model internal combustion engine

Abstract: We optimize the operating conditions of a model internal combustion engine to obtain maximal efficiency. The model engine consists of a cylinder equipped with a piston containing a working fluid, coupled to a heat bath and heated by internal combustion with a rate of heating that is very weakly dependent on the temperature and pressure of the working fluid. We consider operation of the piston under the influence of an external pressure. The model engine includes valves allowing the exhaust and intake of the working fluid. It is found that the optimal operation has an optimal compression ratio and an optimal energy to be exhausted with the working fluid. The results are demonstrated with a numerical example. Also presented are optimizations for this system of the average power, and optimization of the work for a given specified average power.

Finite amplitude method for the determination of the acoustic nonlinearity parameter B/A

Abstract: The acoustic nonlinearity parameter B/A is determined using a method based on the finite amplitude distortion of a sine wave emitted by a piston. We measure the growth of the second harmonic component of this wave using a piston receiver, which is coaxial with and the same size as the source. In order to determine B/A, the experimental measurements are compared to a theory which incorporates the nonlinearity parameter. The theory developed for this study accounts for the influence of both diffraction and attenuation on the experimental measurements. For this reason, the method is more accurate than previous techniques that employ plane wave theory for a lossless medium. To test the measurement method, we compare the experimental results for B/A in distilled water, ethylene glycol and glycerol to established values. The agreement between these values suggests that the measurement accuracy is plus or minus 4% for common liquids. [Work supported by ONR.]

Method and apparatus for producing electrical energy from a cyclic combustion process utilizing coupled pistons which reciprocate in unison

Abstract: Method of and device for producing electric energy from a cyclic combustion process. The device includes two oppositely disposed aligned spark ignited internal combustion engine cylinders axially spaced from each other, means rigidly connecting the pistons so that they reciprocate in unison in their respective cylinders, and a reciprocable electrical linear generator-motor unit driven by said reciprocatory piston system. The generator-motor unit includes a very light coreless (ironless) coil rigidly attached to and reciprocatory with the piston system, the said coil reciprocating through a constant strength magnetic field. The beginning of the combustion process (or cycle) in each combustion chamber takes place at the lowest possible compression ratio sufficient for the initial ignition of the fuel-air mixture, the combustion process proceeding at a diminishing volume under the pressure from the compression- and combustion-forces of the opposite combustion chamber-piston system. The combustion process terminates after some extreme point at an expanding volume, whereby the resulting forces are used for compression in the opposite combustion chamber and there the cycle being repeated, which processes (cycles) are taking place under a positive feed-back relation. Because said feed-back relation is very pronounced, this results in a height velocity and a reciprocating rate of the connected piston system whereby there is induced an electromotive voltage in the coil.

Operation device for clutch master cylinder with means to adjust the play stroke of the clutch lever

Abstract: An operation device of a clutch master cylinder including a clutch master cylinder slidably incorporating therein a piston and a clutch lever pivotally supported by a pivot on a lever holder and having a piston operating arm. The clutch lever has a bearing hole formed substantially parallel to the pivot and a rotor is turnably fitted into the bearing hole. A push rod which comes into contact with the piston so as to be able to rock is interconnected to the rotor. To adjust the play stroke of the clutch lever, the length of the push rod is adjustable in one embodiment of the invention. In another embodiment, the pivot is fitted to a shaft hole of the clutch lever and the axis of the pivot is eccentrically disposed with respect to the center of the shaft hole.

Apparatus for controlling the position of a mineral mining machine

Abstract: Apparatus for controlling the position of a mineral mining machine, such as a plow, guided for movement along a guide, employs inclined piston and cylinder units connected between connectors at the ends of elongate beams or rods guided on support units and brackets on a conveyor supporting the guide. The units have cylinders coupled via ball-and-socket joints to the brackets and these joints are disposed above pivot joints linking the conveyor to the connectors. The piston rods of the units are received in pockets in the connectors and flexibly and pivotably coupled thereto.

System for stabbing well casing

Abstract: Apparatus for stabbing well casing to join casing sections to each other, including a rotary table assembly for supporting a casing section in a well bore, a derrick over the rotary table assembly, a crown block at the top of the derrick, a first piston and cylinder subassembly pivotally mounted on one side of the derrick over the rotary table assembly and below the crown block for pivotation about a horizontal axis, a second piston and cylinder subassembly pivotally mounted on a second side of the derrick for pivotation about a horizontal axis, with said second piston and cylinder subassembly located over the rotary table assembly and below the crown block and extending substantially normal to the direction of extension of the first piston and cylinder subassembly, cooperating casing clamping elements carried on the piston rods of the first and second piston and cylinder subassemblies, and counter balancing subassemblies connected to the first and second piston and cylinder subassemblies for pivoting the first and second piston and cylinder subassemblies to a vertically extending inoperative position.

Fuel injection system for internal combustion engines

Abstract: A fuel injection system for an internal combustion engine employing a rotary valve for delivering fuel to fuel injectors in which fuel injection timing is precisely controlled to an optimum range by automatically controlling the rotary valve in response to the number of revolutions of the engine. The system includes a high pressure accumulator connected to a fuel pump and a low pressure accumulator connected to a tank through a variable restrictor valve. The rotary valve functions to selectively connect each injector to the high and low pressure accumulators as it rotates whereby metered amount of fuel can be fed into a plunger chamber of each injector when a piston chamber of the injector is connected to the low pressure accumulator and the fuel can be injected through nozzle orifices when the piston chamber is connected to the high pressure accumulator.

Multidose jet injector

Abstract: A multidose jet injector having a main cylindrical body assembly with a jet discharge orifice in its closed forward end and which encloses an internal injector piston element. The piston element can be cocked against heavy spring pressure and, in its cocked position, defines a medicament delivery chamber between the closed end of the main body assembly and the head of the piston. A reciprocative piston puller element is located within the main body assembly, rearward of the piston element, and is connected to a medicament pump cylinder which is enclosed within an elongated rearward tubular portion of the piston element. The puller element is used to pull the piston element to its cocked position and thereafter to reciprocate the medicament pump cylinder to first aspirate a controlled volume of medicament liquid from its supply vial to a medicament transfer chamber (formed within the rearward section of the tubular portion of the piston element) and then pump such medicament via a cannula passageway through the pump body and injector piston to the medicament delivery chamber. The main cylindrical body assembly includes a medicament apportionment mechanism which simultaneously adjusts the respective volumes of the medicament delivery chamber and medicament transfer chamber to allow for changes in desired medicament dosage quantities. Upon release of the injector piston from its cocked position, spring pressure imparts fast and powerful movement to such piston and medicament is ejected from the delivery chamber through the discharge orifice of the injector.

Fuel injection apparatus for internal combustion engines

Abstract: The fuel injection quantity of a fuel injection apparatus provided with a fuel injection pump is electrically regulated by means of the opening duration of a metering valve. Additionally, a shift in the instant of supply onset controlled in accordance with operating characteristics is attained by means of a change in the return-flow fuel quantity, which is diverted into a refill reservoir and then refilled completely into the pump work chamber by the beginning of the next subsequent injection stroke. Serving as the sole connection between the refill reservoir and a pump work chamber is an overflow conduit, the overflow opening of which, located at the discharge location into the pump work chamber, is opened by two control locations on the pump piston at the end of supply and once again shortly before bottom dead center. The two control locations are embodied by an oblique control edge on the pump piston that determines the end of supply and by a horizontal, end-face control edge, with the horizontal control edge assuring that shortly before bottom dead center any remnant quantity of the return-flow fuel still remaining in the refill reservoir is refilled back into the pump work chamber.

Convertor for thermal energy into electrical energy using Stirling motor and integral electrical generator

Abstract: The present invention relates to external combustion engines and more precisely to motors using the Stirling cycle designed to directly convert thermal energy into electrical energy. In accordance with the invention, this transformation is carried out inside a machine which is completely sealed, without a mechanical connection with the outside, in which the power piston drives the moveable part of an electrical generator. In accordance with one preferred embodiment, this electrical generator is a linear alternator. In accordance with a further original feature of the invention, control of the coupling between the displacing piston and the power piston is carried out by using electronic regulation.

Reciprocating solar engine

Abstract: A reciprocating solar engine includes at least one cylinder 3 which has an essentially transparent head 4 and a pistion 12 disposed in the cylinder 3. A gas-particle mixture 7, 8 is injected into the cylinder 3 between the piston 12 and the transparent head 4. Radiant solar flux is directed through the transparent head 4 so that the gas-particle mixture 7, 8 is heated and the piston 12 is pushed away from the transparent head 4. The engine further includes a device for allowing the radiant energy flux to be directed at the transparent head 4 during only a portion of the operating cycle of the engine.

Tester valve with silicone liquid spring

Abstract: A flow tester valve apparatus includes a housing having a flow passage disposed therethrough with a flow valve disposed therein for opening and closing the flow passage. A power mandrel is disposed in the housing and includes a power piston. The power mandrel is operatively associated with the flow valve for moving the flow valve from its closed position to its open position. A power port transmits pressure from a well annulus to a first side of the power piston. A first chamber is disposed in the housing and filled at least partially with a compressible liquid and a second side of the power piston is in fluid communication with the first chamber. A second chamber is disposed in the housing and includes a floating piston which divides the second chamber into a first zone and a second zone. An equalizing port is disposed in the housing for transmitting pressure from the well annulus to the second zone of the second chamber. Pressurizing and depressurizing passages communicate the first chamber with the first zone of the second chamber. A first back pressure check valve and a first flow restrictor are disposed in the pressurizing passage. A second back pressure check valve and a second flow restrictor are disposed in the second passage. The power piston may include a main piston and a booster piston.

Low tire pressure alarm system

Abstract: A tire pressure alarm system primarily adapted for the monitoring of tire pressure in the pneumatic tires of coaxial dual wheels on a vehicle including a pneumatic cylinder mounted diametrically on the hub of the outboard wheel and having its end portions coupled by fluid hoses to the air valves of the respective inboard and outboard tires. The cylinder includes a reciprocal piston member normally biased to a axial central position defining air detector chambers at opposite ends of the cylinder for communication with the respective air valve stems. The piston member carries a pair of axially spaced switch elements movable with the piston member for actuating switch sensor elements spaced along the cylinder for generating alarm signals corresponding to predetermined tire pressures in the respective inboard and outboard tires. The pneumatic cylinders are substantially centrifugally balanced on the hub of the outboard wheel.

Integral shock absorber and spring assembly

Abstract: Disclosed is a tilt cab suspension system comprising integral shock absorber and air spring assemblies located between the truck frame and the cab. The shock absorber assembly comprises a hydraulic circuit which provides for circulation of hydraulic fluid during an upstroke and/or downstroke of a piston within a cylinder. A selectively adjustable control valve is located in the hydraulic circuit and may be regulated by the vehicle operator to control the stiffness of the shock absorber sub-assembly and, consequently, the hardness of the ride.

Characteristics of a Slipper Bearing for Swash Plate Type Axial Piston Pumps and Motors : 1st Report, Theoretical Analysis

Abstract: A slipper bearing is one of the factors which affect significantly the performance of swash plate type axial piston machines. In this paper, considering all the oil-film parameters, that is, tilting angle, maximum tilting angle azimuth and mean clearance, a theoretical analysis on the characteristics of the slipper bearing is made from the standpoint of fluid film lubrication. As numerical examples, changes in the oil-film parameters due to a rectangular change of a supply pressure are shown. And also, the limit of fluid film lubrication is given in relation to the supply pressure and the rotational speed.