Abstract:
A method of detecting the occurrence of impact or collision between a cylinder (2) and piston (1) driven by a linear motor of a gas compressor includes the steps of i) obtainment of a reference signal (Sr) associated to an electrical output of the linear motor before the piston attains the upper dead center; ii) obtainment of a detection signal (Sd) associated to said electrical output of the linear motor after the piston attains the upper dead center; iii) comparison between the reference signal (Sr) and the detection signal (Sd); and iv) record of occurrence of impact when the result of comparison of step iii indicates that the detection signal (Sd) presents a variation deriving from impact between the cylinder (2) and the piston (1), considering a pre-established tolerance. Also disclosed is an electronic detector device capable of executing the methodology described above. A gas compressor (100) and a control system including the above-mentioned detector are also disclosed.
Abstract:
A high pressure slurry plunger pump is described which provides a clean fluid buffer around the suction and discharge valves of the pump and in some cases in the vicinity of the plunger seal mechanism in order to displace erosive slurry material and thus extend the life of the pump and improve pump efficiency.
Abstract:
A method is provided for compressing a gas in a single cycle and in a single cylinder to a pressure of at least 17.2 Mpa with a compression ratio of at least about five to one. The method further comprises dissipating heat from the cylinder during the compression stroke whereby the gas is discharged with a temperature significantly less than isentropic. The apparatus comprises a hollow cylinder and a reciprocable free-floating piston disposed therein. The piston divides the cylinder into: (a) a compression chamber within which a gas can be introduced, compressed, and discharged; and, (b) a drive chamber, into which a hydraulic fluid can be introduced and removed for actuating the piston. The apparatus further comprises a piston stroke length to piston diameter ratio of at least seven to one. For operating the apparatus with a compression ratio of at least five to one, an outlet pressure of at least 17.2 Mpa, and a gas discharge temperature significantly less than isentropic, the apparatus can further comprise a variable displacement hydraulic pump for controlling piston velocity, an electronic controller for maintaining an average piston velocity that is less than 0.5 feet per second, and a heat dissipator for dissipating heat from the cylinder.
Abstract:
A portable pumping system provides insulin or other drugs to a user. A shape memory element is used to actuate the pump and an intelligent system controls the actuator in order to minimize stresses within the system and provide accurate and reliable dosage delivery. The control system utilizes various types of feedback to monitor and optimize the position of the pumping mechanisms. Physical design aspects also minimize stress and the combination of the physical design aspects and the intelligent operation of the system results in a lightweight and cost effective pump that may be used in a disposable fashion if desired.
Abstract:
Various methods and devices are provided for an electrokinetic infusion pump. In one embodiment of the invention, the infusion pump includes an infusion pump module, which can be configured to dispense an insulin containing infusion liquid, and an electrokinetic engine. The infusion pump module includes a capacitive displacement position sensor configured for sensing a dispensing state of the infusion pump module. The infusion pump module can include an infusion module housing and the electrokinetic engine can include a moveable partition. The capacitive displacement sensor includes a first capacitive plate disposed on the moveable partition and a second capacitive plate disposed on the infusion module housing. The capacitive displacement sensor is configured for measuring capacitance between the first capacitive plate and the second capacitive plate and can send a feedback signal to a closed loop controller that is indicative of the capacitance between the first and second capacitive plates.
Abstract:
The occurrence of fluctuations in liquid chemical during the discharge and intake thereof in a device that employs a liquid chemical supply pump 10 that discharges liquid chemical taken in by means of a change in volume inside a pump chamber 16 that accompanies the displacement of a bellows type partition 14. The amount of fluctuation in the bellows type partition member 14 that accompanies the operation of a discharge side valve 32 will be detected by a displacement sensor 58. The amount of fluctuation is a parameter that indicates a correlation with the abrupt flow of liquid chemical that accompanies the opening of the discharge side valve 32. Thus, the amount of fluctuation will be reduced, and the pressure inside a pump chamber 16 prior to the opening of the discharge side valve 32 will be controlled.
Abstract:
A linear motor (10), a linear compressor (100), a method of controlling a linear compressor (100), a cooling system (20) and a system of controlling a linear compressor (100) to operate a linear compressor (100) in resonance in it's the greatest possible efficiency throughout its operation are described. One of the ways of achieving these objectives is by means of a linear compressor (100) applicable to a cooling system (20), the linear compressor (100) comprising a piston (1) driven by a linear motor (10), the piston (1) having displacement range controlled by means of a controlled voltage (VM), the controlled voltage (VM) having a voltage frequency (φp) applied to the linear motor (10) and adjusted by a processing unit (22), the range of piston (1) displacement being dynamically controlled in function of a variable demand of the cooling system (20), the linear compressor (100) having a resonance frequency, the processing unit (22) adjusting the range of piston (1) displacement, so that the linear compressor (100) will be dynamically kept on resonance throughout the variations in demand of the cooling system (20).
Abstract:
Systems and methods for compensating for pressure increase which may occur in various enclosed spaces of a pumping apparatus are disclosed. Embodiments of the present invention may compensate for pressure increases in chambers of a pumping apparatus by moving a pumping means of the pumping apparatus to adjust the volume of the chamber to compensate for a pressure increase in the chamber. More specifically, in one embodiment, to account for unwanted pressure increases to the fluid in a dispense chamber the dispense motor may be reversed to back out piston to compensate for any pressure increase in the dispense chamber.
Abstract:
The present invention relates to a fluid pump and a fluid-transfer plate and a sensor for a fluid pump, particularly applicable to linear compressors, for detecting the position of the respective piston and preventing the latter from colliding with the fluid-transfer plate upon variations in the compressor operation conditions, or even variations in the feed voltage. The objectives of the present invention are achieved by means of a fluid pump (1) comprising a piston (2) that is axially displaceable within a cylinder (3), the cylinder (3) comprising a cylinder closing fluid-transfer plate (40), the piston (2) being displaced toward the fluid-transfer plate (40) and capturing a gas or fluid from a low-pressure environment (11), and the fluid pump (11) comprising a sensor assembly (98), which includes an inductive sensor (8) associated with the fluid-transfer plate (40). The objectives of the present invention are also achieved by means of a fluid-transfer plate (40) particularly applicable to a fluid pump (1) and that comprises a valve plate (4) provided with a though-bore (10) for associating a protector (9) that cooperates with the cavity (10), the protector (9) comprising at least one sensor cavity (8′) for associating an inductive sensor (8). An inductive sensor (8) is also foreseen, which is applicable to the fluid pump (1).
Abstract:
In an effective method for starting a piston compressor which is easy to implement, and a piston compressor suitable for carrying out the method, there is provision, in a resetting phase, for driving a piston of the piston compressor in the direction of a compression point of the piston position by the application of a resetting drive moment. The resetting drive moment being maintained until the piston has reached a starting position by overstepping a steady-state point as a result of displacement of fluid out of the compression space, formed between the piston and a corresponding pressure cylinder, through at least one leakage point. In a subsequent acceleration phase, the piston is then accelerated out of the starting position into an operational direction of rotation with a starting drive moment.