Abstract:
A linear compressor having a core combined to one end of a piston to detect a position of the piston reciprocally moving up and down, and a bobbin having a first sensor coil and a second sensor coil that detect the position of the core. A controller determines the state of a load on the piston by measuring the time the core takes to exit and enter the bobbin from an inhale stroke through a compression stroke of the piston and control a position of the piston based on the measured state of the load. A method for controlling the operation of the linear compressor including timing the core driven by a piston through a stroke cycle, receiving the time and computing a load on the piston, outputting a piston position signal based on the load computed, and controlling a piston stroke according to the piston position signal, by varying the power driving the linear compressor.
Abstract:
An apparatus and a method are disclosed for controlling operation of a compressor capable of greatly decreasing a stroke estimation error of a compressor and controlling operation of the compressor accurately and precisely. The method includes calculating a first stroke estimation value of a compressor on the basis of current, a voltage applied to a motor of a compressor and preset parameters of the motor. Detecting a counter electromotive force of the motor and calculating a second stroke estimation value of the compressor on the basis of the detected counter electromotive force value. Determining a new stroke reference value by comparing the first stroke estimation value with the second stroke estimation value, adding or subtracting a stroke compensation value corresponding to the comparison result to or from a preset stroke reference value, and controlling a stroke of the compressor by varying a voltage applied to the motor on the basis of the determined stroke reference value and the first stroke estimation value.
Abstract:
A pump for ultra-pure fluids comprises a flexible diaphragm separating a fluid chamber from an air chamber. The diaphragm creates an airtight seal between the fluid chamber and the air chamber. Any leak from the fluid chamber into the air chamber is detected by a fiber optic system comprising an element and two optical fibers that are disposed such that light is detected by the second optical fiber only when the element is not in contact with liquid. A second fiber optic system can also be used to determine the stroke of an oscillating member by disposing the fiber optic lines at an angle calculated to reflect light off of the oscillating member when the member arrives at a predetermined location. The fiber optics are adapted to be resistant to corrosion, non-igniting, and non-contaminating.
Abstract:
An apparatus and method for controlling the maximum stroke of a linear compressor is provided. The shorting of the normal supply voltage of a compressor to ground is used to detect overstroking. A plurality of transistors are electrically coupled to the control circuit that is electrically coupled to a linear compressor. When the compressor's stroke exceeds it maximum stroke marked by the refrigerant barrel of the compressor making physical contact with the armature, a signal is received by the control circuit. The control circuit processes this signal and sequences the transistors to return the extended stroke of the compressor to its maximum stroke.
Abstract:
Disclosed is a circuit for driving a linear compressor enabling to reduce a cost in detecting voltage and current applied to a linear compressor by decreasing the number of precision resistors. The present invention includes a linear compressor controlling a cooling capacity by varying a stroke through an up-and-down straight-line motion of a piston, an electric circuit part supplying the linear compressor with voltage and current in accordance with a switching signal of an AC switching device through a current detect resistor and the AC switching device wherein a ground terminal is connected between the current detect resistor and linear compressor, a voltage detection unit detecting the voltage applied to the linear compressor by taking the ground terminal as a reference and outputting the detected voltage, a stroke calculation unit receiving the detected current and voltage to calculate the stroke, a speed or an acceleration speed of the linear compressor, and a microcomputer inputting a switching signal for controlling the voltage applied to the linear compressor into the switching device to make a present stroke follow an initial stroke reference.
Abstract:
In an apparatus and a method for controlling operation of a linear compressor, operation of a linear compressor is controlled by finding each inflection point as a TDC (top dead center) is 0 by using a current and a displacement vector generated in the linear compressor, determining a duty ratio on the basis of the inflection point and generating a switching control signal according to the determined duty ratio.
Abstract:
In an apparatus and a method for controlling operation of a reciprocating compressor which is capable of operating a compressor stably by detecting a phase difference and using an inflection point of the phase difference, an apparatus and a method for controlling operation of a reciprocating compressor including an electric circuit unit operating a reciprocating compressor by varying a stroke with motion of a piston, a phase difference detecting unit detecting a phase difference of a current and a voltage from the electric circuit unit, a phase inflection point detecting unit detecting a phase inflection point by being inputted the phase difference, and a stroke controlling unit being inputted the detected phase inflection point from the phase inflection point detecting unit and applying a voltage, to the electric circuit unit in order to make the stroke correspond to the phase inflection point can control a TDC of a piston regardless of load variation, improve an operation efficiency of a reciprocating compressor, and because a stroke calculating circuit is not required, there is no stroke calculating error according to the motor constant variation, in addition, it is possible to operate a reciprocating compressor by corresponding instantly to a load and operate the reciprocating compressor in a safe region in sensing of an overload by grasping the present load condition using a reference value of a phase difference.
Abstract:
A proportioning dispenser for proportioning at least two components which are each supplied via a pump unit from an associated accommodating compartment is disclosed. The adjustment of the mixing ratio is effected via a transmission member the point of application of which is adjustable with respect to the two pump units.
Abstract:
A two-stage reciprocating compressor is provided. The compressor includes a block with a single cylinder and associated single compression chamber and single piston. The compressor further includes a crankshaft. The crankshaft has an eccentric crankpin that is operatively connected to the piston. A reversible motor is provided to rotate the crankshaft in a forward direction and in a reverse direction. An eccentric cam is rotatably mounted on the eccentric crankpin. The eccentric cam is held stationary with respect to the crankpin when the crankshaft is rotating in the forward direction. When rotating in the forward direction, the crankshaft drives the piston at a full stroke between a bottom position and a top dead center position. The eccentric cam rotates with respect to the crankpin when the crankshaft is rotating in the reverse direction. When rotating in the reverse direction, the crankshaft drives the piston at a reduced stroke between an intermediate position and the top dead center position.
Abstract:
A pump having both a short stroke pumping mode and a long stroke pumping mode. The pump has two material cylinders, each with an attached hydraulic cylinder for operating a piston rod extending through both the material and hydraulic cylinders. The piston rods are driven by hydraulic fluid supplied to the hydraulic cylinders and are synchronized so that as one piston rod extends, the other piston rod retracts. The piston rods draw material into the material cylinders when retracting, and pump material out of the material cylinders when extending. To pump in a short stroke mode, a diverter valve is placed between the hydraulic pump and the hydraulic cylinders which diverts an amount of hydraulic fluid to the cylinders, causing the hydraulic pistons to only be extended about half the length of the hydraulic cylinder.