Abstract:
A linear compressor (100) applicable to a cooling system (20) includes 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:
A method for preventing pack-out in a system for pumping hybrid hot-melt material comprises monitoring activity of a pump that pumps hybrid hot-melt material, shutting off a heater that melts pumped hybrid hot-melt material at an inactivity threshold level, and relieving pump pressure.
Abstract:
An actuation system for a resonant linear compressor (50), applied to cooling systems, the latter being particularly designed to operate at the electromechanical frequency of said compressor (50), so that the system will be capable of raising the maximum power supplied by the linear actuator, in conditions of overload of said cooling system. Additionally, an actuation method for a resonant linear compressor (50) is disclosed, the operation steps of which enable one to actuate the equipment at the electromechanical resonance frequency, as well as to control the actuation thereof in over load conditions.
Abstract:
Detection of end of stroke for an electromagnetic pump may be performed using, for example, a calculated first flux derivative. Further, inductance of a coil that can be energized to produce a pump stroke may be calculated (e.g., the pump may include an actuator moveable in response to the energization of the coil). For example, the inductance may be calculated as a function of sense coil current and source electrical potential when the actuator is not moving for use in determining position of the actuator.
Abstract:
Embodiments of the present invention provide pumps with features to reduce form factor and increase reliability and serviceability. Additionally, embodiments of the present invention provide features for gentle fluid handling characteristics. Embodiments of the present invention can include a pump having a motor driven feed stage pump and a motor driven dispense stage pump. The feed stage motor and the feed stage motor can include various types of motors and the pumps can be rolling diaphragm or other pumps. According to one embodiment, a dispense block defining the pump chambers and various flow passages can be formed out of a single piece of material.
Abstract:
A method for increasing compressed air efficiency in a pump utilizes an air efficiency device in order to optimize the amount of a compressed air in a pump. The air efficiency device may allow for controlling the operation of the air operated diaphragm pump by reducing the flow of compressed air supplied to the pump as the pump moves between first and second diaphragm positions. A sensor may be used to monitor velocity of the diaphragm assemblies. In turn, full position feedback is possible so that the pump self adjusts to determine the optimum, or close to optimum, turndown point of the diaphragm assemblies. As such, air savings is achieved by minimizing the amount of required compressed air.
Abstract:
Embodiments of the present, invention provide a system and method for reducing the hold-up volume of a pump. More particularly, embodiments of the present invention provide a system and method for determining a home position to reduce hold-up volume at a dispense pump and/or a feed pump. The home position for the diaphragm can be selected such that the volume of the chamber at the dispense pump and/or feed pump contains sufficient fluid to perform the various steps of a dispense cycle while minimizing the hold-up volume. Additionally, the home position of the diaphragm can be selected to optimize the effective range of positive displacement.
Abstract:
A magnetic drive metering pump in which a movable thrust member is fixed to a diaphragm and is axially movable in a magnet shroud. The thrust member, on electrically actuating the magnet shroud, is drawn into the magnet shroud against the force of a recuperating spring, and after deactivating the magnet shroud, is returned to a starting position. The diaphragm cooperates alternately with an outlet and an inlet valve to produce a pump stroke in a pump metering head. The magnetic drive metering pump has a reference element associated with the thrust member and diaphragm, the position of which reference element is detected by a positional sensor. The positional sensor provides a signal which has a fixed relationship to the position of the reference element, and the motion of the thrust member is controlled by a control circuit such that it follows a predetermined nominal profile.
Abstract:
A method for controlling operation of a pump unit, where the pump unit includes a primary piston pump having a primary piston and a secondary piston pump having a secondary piston. The primary piston pump is fluidically connected with the secondary piston pump. The primary piston pump includes an inlet valve and an outlet valve, and the pump unit operates periodically according to a pump cycle. The method includes determining a fluid pressure of fluid dispensed by the pump unit, and performing a closed loop control of a position of the primary piston in dependence on the fluid pressure of the fluid dispensed by the pump unit during a first time interval of the pump cycle.
Abstract:
A variable displacement axial piston machine. The variable displacement axial piston machine includes a cylinder block with at least one main cylinder and main piston, a swash plate, a plunger arrangement with a plunger and auxiliary cylinder, and a sensor. The swash plate is arranged to effect movement of the main piston in the main cylinder upon rotation of the swash plate relative to the cylinder arrangement. The plunger is arranged to tilt the swash plate relative to the cylinder arrangement and to control a stroke of the main cylinder in the main piston. To provide a simple and reliable measurement of displacement of the main piston in the main cylinder, the invention provides a sensor element which is fixed in the auxiliary cylinder and which is adapted to sense movement of the plunger therein.