Abstract:
An apparatus for controlling an operation of a reciprocating motor compressor includes a current integrator for integrating an alternating current applied to a motor of the compressor during each one cycle thereof; and a controller for differently controlling a firing angle of a triac during the positive phase and the firing angle of the triac during the negative phase of the AC voltage applied to the motor based on the integrated value of the current. A loss in the motor can be reduced by avoiding presence of a DC component in the current applied to the motor of the compressor.
Abstract:
An apparatus for controlling an operation of a reciprocating compressor includes a inductance increasing device connected to a motor of the reciprocating compressor, so that a surge current generated when power is applied to the reciprocating compressor at an initial stage is reduced and thus an initial stroke of the reciprocating compressor is reduced. Accordingly, operational efficiency of the reciprocating compressor is improved.
Abstract:
A method for determining the piston stroke of a reciprocating piston machine having a variable stroke, for example a swashplate compressor, a pivoting plate compressor or a pivoting ring compressor, especially for air-conditioning installations in motor vehicles.
Abstract:
An apparatus for controlling an operation of a compressor includes a controller for generating a control signal for selecting an operation mode of a compressor according to an operation load of the compressor; a first switching unit connected to a motor consisting of a main coil and a sub-coil and selecting the main coil or both the main coil and the sub-coil according to the control signal; first and second capacitors electrically connected with the first switching unit; and a second switching unit connected to the first capacitor and selectively connecting the first capacitor in parallel to the second capacitor according to the control signal.
Abstract:
A control system is provided for controlling the movement of the piston of the fluid-pumping device, the piston being displaceable in a block of the fluid-pumping device and being driven by a motor fed by a voltage, comprising a semiconductor electronic system cyclically applying the voltage to the motor to move the piston, a resistive element, a capacitive element, a piston-position sensor to indicate the passage of the piston by a point at the block, the capacitive element being charged by means of the resistive element, at each cycle of application of voltage to the motor, the capacitive element being discharged, at least partly, when the piston passes by the point.
Abstract:
A stabilizing structure for a throw adjusting eccentric cam in a two-stage reciprocating compressor is provided. The compressor includes a block that has at least one cylinder with an associated compression chamber and piston, a crankshaft that includes an eccentric crankpin, and a reversible motor for rotating the crankshaft in a forward and a reverse direction. An eccentric, two position cam is rotatably mounted over the crankpin. The cam rotates to and operates at a first position relative to said crankpin when the motor is running in the forward direction and rotates to and operates at a second position relative to said crankpin when the motor is running in the reverse direction. The combined eccentricities of the crankpin and the cam cause the piston to have a first stroke when the motor operates in the forward direction and a second stroke when the motor operates in the reverse direction. There is also provided a control for selectively operating the motor either in the forward direction or in the reverse direction.
Abstract:
Digital fluid pumps having first and second electromagnetic actuators formed in part by a piston to alternately drive the piston in opposite directions for pumping purposes. The piston motion is intentionally limited so that the electromagnetic actuators may operate with a high flux density to provide an output pressure higher than that obtained with conventional solenoid actuated pumps. The electromagnetic actuator coils are electrically pulsed for each pumping cycle as required to maintain the desired fluid flow and output pressure, with the piston being magnetically latchable at one or both extreme positions between pulses. Alternate embodiments and control methods and systems are disclosed.
Abstract:
A reciprocating compressor includes a linear motor having a piston reciprocating inside a cylinder. A cylinder head is provided with suction and discharge orifices. A valve means is mounted inside the cylinder and has an operative position, seated against the discharge orifice. The operative position is defined when the top of the piston is within a certain distance from the cylinder head. The distance is defined, so that, at the end of the compression stroke of the piston, a determined pressure is reached inside the cylinder, and the pressure results in a force on the piston. The force is opposite to a force which is impelling the piston and which is sufficient to interrupt its compression stroke before impacting the cylinder head.
Abstract:
A piston stroke limiting device for a reciprocating compressor of the type including a piston (2) reciprocating inside a cylinder (3), which is closed by a cylinder head (4) and defines, between the latter and the top of the piston (2), a compression chamber (5), said device comprising: a driving element (40) provided in one of the parts defined by the piston (2) and the cylinder head (4) and projecting to the inside of the compression chamber (5), in order to touch the other of said parts when the piston (2) surpasses a predetermined nominal position at the end of the compression stroke; and a relief valve (60), which is selectively displaced from a closed condition, in which it is seated on a respective valve seat (51) defined in a relief passage (50) communicating the compression chamber (5) with a region of the compressor subject to a substantially lower operational pressure, to an open condition, by action of the driving element (40), when the piston (2) surpasses said predetermined nominal position at the end of the compression stroke.
Abstract:
An apparatus and a method for controlling operation of a linear motor compressor, by which a linear motor compressor can operate always in an optimum condition by coping with the load variation due to changes in a refrigerator and the circumstances. In more detail, a current peak value at TDC=0 is detected by comparing a current applied to the linear motor compressor with a formerly detected current, and accordingly the linear motor compressor is operated by a switching control signal generated according to a duty-ratio corresponding to the current peak value.