Abstract: The present invention relates to a cooling system of a refrigerator, particularly of a refrigerator including a refrigeration compartment and a freezer comprising a compressor attached to at least one condenser by a segment of a refrigerant tube, wherein a first refrigerant line leaves from the condenser and returns to the compressor, and a second refrigerant line leaves from the condenser and returns to the compressor. In the preferred embodiment of the present invention, the compressor has at least two suction inlets, wherein the first refrigerant line is connected to the first inlet and the second refrigerant line is connected to the second inlet, and both inlets have each a suction valve.

Abstract: System and method of remotely connecting and disconnecting an auxiliary power supply of the frequency inverter for variable capacity compressors employed in cooling systems. The inverter includes a circuit breaker that when it receives an external signal to activate the auxiliary power supply indicating that the auxiliary supply should be connected, the circuit breaker enables the auxiliary power supply, which activates the inverter. The inverter begins sending, continually, the internal maintenance signal to activate the auxiliary supply to the circuit breaker indicating that the auxiliary supply should be kept running, making the circuit breaker maintain the auxiliary power supply enabled.

Abstract: Linear compressor comprising a resonant linear motor (4) having a stator (9) and a linear displacer (3), the linear motor (4) cooperating with a resonant spring (2) that is driven by the linear displacer (3) at one of the ends of the resonant spring (2) with the opposite end of the resonant spring (2) cooperating with a mechanical actuation element (1). A variation sensor of magnetic flux (5) cooperates with the resonant spring (2). Said variation sensor of magnetic flux (5) comprising a fixed part (7) and a movable part (6), the movable part (6) coupled to the end of the resonant spring (2) opposite to the end cooperating with the linear displacer (3). The variation sensor of magnetic flux (5) is the sole means required to determine the displacement amplitude and the frequency of oscillation of the displacer (3) of the linear motor (4). Corresponding method for controlling the stroke in such a linear compressor.

Abstract: The metallurgical composition includes a main particulate metallic material, for example iron or nickel, and at least one alloy element for hardening the main metallic material, which form a structural matrix; a particulate solid lubricant, such as graphite, hexagonal boron nitride or mixture thereof; and a particulate alloy element which is capable of forming, during the sintering of the composition conformed by compaction or by injection molding, a liquid phase, agglomerating the solid lubricant in discrete particles. The composition may include an alloy component to stabilize the alpha-iron matrix phase, during the sintering, in order to prevent the graphite solid lubricant from being solubilized in the iron. The invention further refers to a self-lubricating sintered product, obtained from the composition, and to the process for obtaining said product.

Abstract: A flow restrictor is adapted for application in a bearing arrangement between a piston and a cylinder of a gas compressor. The compressor includes a protective block that involves the cylinder externally, and also includes at least one inner cavity, which is fluidly fed by a discharge flow resulting from a compression movement exerted by the piston inside the cylinder. The compressor includes a bearing-arrangement clearance that separates the piston and an inner wall of the cylinder. The compressor includes at least one flow restrictor provided with a housing that associates fluidly the inner cavity to the bearing-arrangement clearance. The flow restrictor is associated to the housing by a process of at least partial plastic deformation inside the housing, the flow restrictor being provided with channels for passage of fluid, the plastic deformation being sized for limiting the gas flow through the inner cavity to the bearing-arrangement clearance.

Abstract: The compressor of the invention comprises: a block with a cylinder; a movable assembly formed by a piston reciprocating in the cylinder and coupled to an actuating means by a rod; and a resonant spring having a first and a second diametrical end portion which are attached to the movable assembly by a first fixation means (MF1) and, to the block, by a second fixation means (MF2) which is adjustably attached to the block and to said second end portion so as to affix the latter to the block in a position defined along the displacement of the resonant spring in three directions orthogonal to one another and defined by the direction of the axis of the resonant spring, by the diametrical direction of the second end portion and by the diametrical direction orthogonal to said two first directions, and also along the angular displacement of said second end portion around said three directions orthogonal to each other.

Abstract: The present invention refers to a noise muffler for refrigeration compressors capable of dampening noise generated by the intermittent flow of the compressor and at the same time a muffler that reduces the loss of load in the refrigeration system.

Abstract: The compressor of the invention includes a block (B) defining a shaft hub having a first and a second end portion and housing an eccentric shaft having a median portion radially journalled in the shaft hub, and a free end portion carrying the rotor of an electric motor. The first and the second end portions of the shaft hub define radial bearings for the shaft and a support member is formed by a coupling portion, affixed to the free end portion of the shaft, and by a mounting portion, projecting axially and radially from the coupling portion, externally to the shaft hub and around the median portion of the shaft. The rotor is affixed to the mounting portion, concentrically to the eccentric shaft and surrounding the shaft hub.

Abstract: The present invention discloses a sealing system for a refrigerator and, more particularly, a sealing system located between the doors of a refrigerator and its acclimatized chambers and of the kind that comprises a gasket to be inserted in a receiving channel existing also between the doors of a refrigerator and its acclimatized chambers. The sealing system for refrigerator herein reported consists of at least one gasket comprising a tubular body formed by at least one attaching end and by at least one sealing body; at least one groove defined in at least one movable door or at least one fixed cabinet; and by at least one rib defined in at least one movable door or at least one fixed cabinet.

Abstract: A single-phase induction motor includes a stator including a main winding with a first coil (P1a), a second coil (P1b), a third coil (P2a) and a fourth coil (P2b). The first coil and the third coil are manufactured from a first conductive material (2), the second coil and the fourth coil are manufactured from a second conductive material (3), with resistivity other than that of the first conductive material. The first coil and the second coil are arranged at one of the stator poles (P1) and the third coil and the fourth coil are arranged at the opposite pole (P2). The first coil and the fourth coil are electrically connected through a series connection, configuring a first branch (R1). The second coil (P1b) and the third coil (P2a) are electrically connected through a connection in series, configuring a second branch (R2).

Abstract: The present invention relates to a starting device for a single-phase induction motor, comprising a stator (M) with an running winding (B1) and a starting winding (B2), a starting device (28) connecting the starting winding (B2) to a source (F) of alternate voltage supply, when in a closed state, the start switch (S1) being carried to an open position when the start of the motor is ended, the starting device (28) comprising: a start switch (S1), an electronic signal-processing device (30) receiving current signals originating from a current sensor (RS) flowing through the start switch (S1) and receiving voltage signals from a current zero-crossing sensor SV, wherein the control unit (30) instructs the closing and opening of the start switch (S1) in accordance with the interpretation of the signals by voltage and current zero-crossing sensors, and time sensors.

Abstract: A communication system includes functional modules, wherein at least one functional module includes a processing unit and at least one functional module includes a controllable device. The modules are powered by an alternating voltage at a frequency and are electrically associated by a power bus and a communication bus. The processing unit provides a communication signal to the communication bus for interaction between the functional modules through a plurality of sets of high frequency pulses arranged to repeat at a predetermined repetition frequency substantially greater than the frequency of the voltage, and each set of high frequency pulses forms an information pulse corresponding to at least one bit of a communication protocol. Filters are disposed between an electric energy power supply and the functional modules for permitting the passage only of frequency components of an electric signal greater than the voltage frequency of the electric energy power supply.

Abstract: The present invention relates to a method, a system and an electronic device (15), especially designed for start and control of the functioning of a single-phase induction motor (12). Said motor (12) comprises a run winding (10) and a start winding (11), the start winding (11) is electrically associated to an electronic start device (15), the run winding (10) and the electronic start device (15) are electrically associated to an alternating voltage source (F) configured to supply feed energy to the motor (12), the start winding (11) is kept de-energized at a first operation instant (Top1) of the motor (12).

Abstract: A system for monitoring and controlling a brushless motor associable to an electric power source by means of a rectifier. An actuator assembly is operatively associated to the motor and rectifier. The rectifier is arranged to provide a continuous busbar voltage (Vbar) and a continuous reference voltage (Vref) to the actuator assembly. The actuator assembly includes switches (SW1-6) arranged to energize two phases of the motor simultaneously. The system comprises a voltage observer, associated to the motor and to the actuator assembly, permitting monitoring of an induced voltage in a non-energized phase of the motor. The system includes a control unit associated to the voltage observer. The control unit is arranged to command opening of a switch of the actuator assembly for a time interval to interrupt the power supply to the motor, when the reading of the induced voltage in the non-energized phase presents a value within a voltage interval (dV).

Abstract: The compressor comprises: a cylinder crankcase (1) defining a cylinder (2) closed by a valve plate (3) provided with at least one discharge orifice (3a); a cylinder cap (10) seated against the valve plate (3) and in the interior of which is defined a discharge chamber (11). The present system comprises a hollow body (20) defining at least one plenum (21) mounted internal to the cylinder cap (10), maintaining a gap (30) with the latter. The hollow body (20) is seated against the valve plate (3), preventing the direct contact thereof with the inner volume of the hollow body (20), the latter being provided with an inlet nozzle (22) communicating the plenum (21) with the discharge orifice (3a) of the valve plate (3), and with an outlet nozzle (23) communicating the plenum (21) with a gas outlet (13) of the cylinder cap (10).

Abstract: The compressor comprises: a cylinder crankcase (1) defining a cylinder (2) which is closed by a valve plate (3) provided with at least one discharge orifice (3a) associated with a discharge valve (4) and defining, with the cylinder (2), a compression chamber (C); a cylinder cap (10) seated against the valve plate (3) and inside which is defined a discharge chamber (11). The system comprises an accelerating means (AM) mounted in the interior of the discharge chamber (11) and secured to at least one of the parts of cylinder cap (10) and valve plate (3), in order to receive the entire flow of refrigerant gas released through the discharge orifice (3a), accelerating said gas flow and producing an instantaneous reduction in the pressure gradient between the upstream and downstream sides of the discharge valve (4), in the moment the latter opens.

Abstract: The present invention refers to an acoustic filter for reciprocating compressor and, in special, a suction acoustic filter containing at least one inlet pipeline (21), at least one outlet pipeline (22), and at least one intermediate pipeline (42). Said acoustic filter (1) comprises at least two horizontal chambers (5, 6), wherein said chambers are interconnected by an intermediate pipeline (42), which has a superior portion (421) with a length that is equivalent to approximately 75% to 98% of the height of the first horizontal chamber (5) and an inferior portion (422) with a length that is equivalent to approximately 45% to 80% of the height of the second horizontal chamber (6).

Abstract: Manufacturing a porous component used as flow restrictor includes a metal injection molding process enhanced to obtain a component with open porosity homogeneously distributed. The flow restrictor includes at least one porous component having at least one restricting portion with some porosity dimensioned to regulate the flow of gas to an aerostatic bearing of a mechanical system, such as a hermetic compressor. Use and production of a porous component obtained by powder injection molding or powder injection molding of multi-material parts is also described, the porous component being a flow restrictor with a layer of dense material, with no open pores, on the outer surface parallel to the flow direction in which the flow through the porous component occurs, allowing it to be inserted into the bearing system without interfering with the porous structure of the core (dual porosity). Sealing existing between the porous component and its housing is described.