Abstract: The present invention provides a method for preparing a vinyl chloride-based polymer comprising performing suspension polymerization of vinyl chloride-based monomer, wherein an aromatic hydrocarbon-based compound is added when a pressure change is 0.5 to 1.5 kg/cm2 with respect to an equilibrium pressure at a polymerization temperature in a polymerization reactor after the vinyl chloride-based monomer is added to the polymerization reactor, wherein the aromatic hydrocarbon-based compound comprises a reactive functional group having an intracarbon double bond and a hydroxyl group; and a vinyl chloride-based polymer prepared by the method and having a high polymerization degree and excellent fusion processability.

Abstract: A device for supporting a portable terminal includes a base member fixed to an installing surface, a horizontal rotation member coupled to the base member such that the horizontal rotation member is rotatable in a horizontal direction with respect to the installing surface, wherein a vertical support protrudes from a top surface of the horizontal rotation member, a vertical rotation member coupled to the vertical support such that the vertical rotation member is rotatable in a vertical direction with respect to the installing surface, and a support member formed on one end of the vertical rotation member, wherein the portable terminal is detachably attached to the support member. According to the device, the supporting angel of the portable terminal may be freely controlled and the supporting state may be stably maintained at the controlled angle, so that the convenience in use is improved.

Abstract: The present invention relates to a method of preparing a vinyl chloride-based polymer, and more specifically, to a method comprising the steps of, (S1) preparing a mixture in which a first protective colloid auxiliary agent and a chain regulator are mixed; (S2) preparing a second protective colloid auxiliary agent including the chain regulator activated by stirring the mixture prepared in step (S1); and (S3) performing polymerization by adding a vinyl chloride-based monomer and a polymerization initiator in the presence of the second protective colloid auxiliary agent prepared in step (S2).

Abstract: The present invention provides a method for preparing a vinyl chloride-based polymer comprising performing suspension polymerization of vinyl chloride-based monomer, wherein an aromatic hydrocarbon-based compound is added when a pressure change is 0.5 to 1.5 kg/cm2 with respect to an equilibrium pressure at a polymerization temperature in a polymerization reactor after the vinyl chloride-based monomer is added to the polymerization reactor, wherein the aromatic hydrocarbon-based compound comprises a reactive functional group having an intracarbon double bond and a hydroxyl group; and a vinyl chloride-based polymer prepared by the method and having a high polymerization degree and excellent fusion processability.

Abstract: The present invention provides a method for preparing a vinyl chloride-based polymer and a vinyl chloride-based polymer prepared thereby, the method comprising a step for performing suspension polymerization of a monomer for preparing a vinyl chloride-based polymer in the presence of a polymerization initiator, a dispersant, and water soluble cellulose ether, wherein the dispersant includes a mixture of two or more kinds of polyvinyl alcohol having different degrees of saponification, and the mole average degree of saponification of the polyvinyl mixture is from 76 mol % to 80 mol %, and the water soluble cellulose ether has a gel point of 60° C. to 90° C. and is added before the initiation of polymerization or at a time in which the polymerization conversion rate is 70% or less.

Abstract: The present invention relates to a method for preparing a vinyl chloride copolymer having good heat resistance and a vinyl chloride copolymer produced by the same. In the preparation method, by not injecting an N-substituted maleimide based compound used as a comonomer together with a vinyl chloride monomer at one time in a pre-polymerization step, but in division in a specific ratio, a copolymer with a uniform distribution of the N-substituted maleimide based compound and the vinyl chloride monomer may be easily prepared, and the vinyl chloride copolymer may have good heat resistance. Accordingly, the preparation method of a vinyl chloride copolymer and the vinyl chloride copolymer according to the present invention may be easily applied to industries requiring the copolymer, particularly industries requiring a resin having good heat resistance as well as industries using a vinyl chloride resin.

Abstract: The present invention relates to a method for preparing a vinyl chloride copolymer having good heat resistance and a vinyl chloride copolymer produced by the same. In the preparation method, by not injecting an N-substituted maleimide based compound used as a comonomer together with a vinyl chloride monomer at one time in a pre-polymerization step, but in division in a specific ratio, a copolymer with a uniform distribution of the N-substituted maleimide based compound and the vinyl chloride monomer may be easily prepared, and the vinyl chloride copolymer may have good heat resistance. Accordingly, the preparation method of a vinyl chloride copolymer and the vinyl chloride copolymer according to the present invention may be easily applied to industries requiring the copolymer, particularly industries requiring a resin having good heat resistance as well as industries using a vinyl chloride resin.

Abstract: A device for supporting a portable terminal includes a base member fixed to an installing surface, a horizontal rotation member coupled to the base member such that the horizontal rotation member is rotatable in a horizontal direction with respect to the installing surface, wherein a vertical support protrudes from a top surface of the horizontal rotation member, a vertical rotation member coupled to the vertical support such that the vertical rotation member is rotatable in a vertical direction with respect to the installing surface, and a support member formed on one end of the vertical rotation member, wherein the portable terminal is detachably attached to the support member. According to the device, the supporting angel of the portable terminal may be freely controlled and the supporting state may be stably maintained at the controlled angle, so that the convenience in use is improved.

Abstract: Disclosed is a fluid viscosity measuring device which can measure the viscosity of a fluid such as blood. The fluid viscosity measuring device of the present invention comprises: a first fluid inlet portion in which a fluid, the viscosity of which is to be measured, is injected, and a second fluid inlet portion in which a reference fluid having a standard viscosity is injected; a connection pipe configured to connect the first fluid inlet portion to the second fluid inlet portion and form a passage for the fluid, the viscosity of which is to be measured, and the reference fluid; a plurality of counting channels in communication with the connection pipe at a predetermined distance to be filled with the two fluids flowing along the passage, respectively; and a boundary surface measuring unit configured to count the counting channels filled with the two fluids, respectively.

Abstract: A reciprocating compressor is provided that reciprocates a piston inside a cylinder as a linear motor is driven, to compress a refrigerant by sucking the refrigerant into a compression space between the cylinder and the piston, and then discharge the same. The piston is operated at a top dead center position and in a resonance state by symmetrically applying a voltage even if a load varies. An elastic coefficient of mechanical spring is set in consideration of a degree of shift of the piston influenced by gas springs varied by the load, and an initial value of the piston to maintain stroke of the piston is set so as to correspond to a required cooling capacity condition.

Abstract: A linear compressor is provided that includes a stationary member including a cylinder that provides a space to compress a refrigerant; a movable member linearly that reciprocates with respect to the stationary member, and includes a piston that compresses the refrigerant inside the cylinder and a supporter piston connected to the piston and having a support portion that extends in a radial direction of the piston; front main springs positioned so as to be symmetrical with respect to centers of the piston and the supporter piston, one end of each of which is supported by a front surface of the support portion of the supporter piston and the other end of each of which is supported by the stationary member; a rear main spring positioned at an opposite side of the piston, one end of which is supported by the supporter piston; and a back cover having a support portion that constrains the other end of the rear main spring from moving in a transverse direction.

Abstract: A linear motor for generating a linear reciprocating motion force, and a reciprocating compressor for compressing a refrigerant by employing the linear motor. The linear motor and the reciprocating compressor employing the same can reduce the number of inverter switches by employing a coil unit whose winding method is improved and a power supply apparatus whose connection to the coil unit and other circuits are improved, and can make it easy to control and reduce production costs by simplifying the circuit configuration.

Abstract: There is provided a linear compressor, which can reduce parts production costs and simplify a part installation process by decreasing the number of main springs. The linear compressor comprises: a cylinder providing a space for compressing a refrigerant; a piston linearly reciprocating inside the cylinder to compress the refrigerant; an inner stator; an outer stator; a permanent magnet connected to the piston and linearly reciprocating between the inner stator and the outer stator; a supporter piston connected to the piston, at least part thereof being extended in a radial direction of the piston; a plurality of front main springs positioned on the same axis as the piston, one ends of which being supported by the supporter piston; and one rear main spring positioned on the opposite side of the piston, one end of which being supported by the supporter piston.

Abstract: A linear compressor is provided, which has a reduced number of front main springs among springs continuously transmitting a force so that a piston can move in a resonance condition. The linear compressor includes a hermetic container to be filled with a refrigerant; a linear motor including an inner stator, an outer stator, and a permanent magnet; a piston linearly reciprocated by the linear motor; a cylinder that provides a space to compress the refrigerant; a supporter piston having a connecting portion connected to one end of the piston, a support portion that extends from the connecting portion, and an additional mass member fixing portion that extends from the connecting portion; front main springs, one end of each of which is supported by one surface of the supporter piston; and one rear main spring, one end of which is supported by the other surface of the supporter piston.

Abstract: Disclosed are an operation control device of a compressor, which can reduce motor loss by applying an AC power to a motor of the compressor without a switching operation of a control unit, and a method thereof. The operation control device of the compressor comprises: a capacitor electrically connected to a motor of the compressor and having a predetermined capacitance; a control unit connected in series to the motor of the compressor and applying an AC power to the motor of the compressor according to a control signal; and a controller detecting a load variation amount on the basis of a current and voltage applied to the motor of the compressor and controlling on/off of the control unit according to the detected load variation amount.

Abstract: A reciprocating compressor in which a piston is linearly reciprocated inside a cylinder, for sucking a refrigerant into a compression space, and compressing and discharging the refrigerant. More particularly, a reciprocating compressor which can reduce the number of inverter switches required to apply power to a motor (coil section). The reciprocating compressor having a stationary member and a movable member connected by a plate spring, and having an outer stator consisting of blocks encompassing an inner stator, wherein a length of a lower pole of each block is varied.

Abstract: Disclosed is a fluid viscosity measuring device which can measure the viscosity of a fluid such as blood. The fluid viscosity measuring device of the present invention comprises: a first fluid inlet portion in which a fluid, the viscosity of which is to be measured, is injected, and a second fluid inlet portion in which a reference fluid having a standard viscosity is injected; a connection pipe configured to connect the first fluid inlet portion to the second fluid inlet portion and form a passage for the fluid, the viscosity of which is to be measured, and the reference fluid; a plurality of counting channels in communication with the connection pipe at a predetermined distance to be filled with the two fluids flowing along the passage, respectively; and a boundary surface measuring unit configured to count the counting channels filled with the two fluids, respectively.

Abstract: A linear compressor is provided that includes a shell; a fixed member installed inside the shell, and including a cylinder that provides a compression space for a refrigerant introduced into the shell; a moving member including a piston that compresses the refrigerant sucked into the compression space inside the cylinder, and that is linearly reciprocated with respect to the fixed member; and a suction muffler positioned on or in a suction passage of the refrigerant inside the shell. A suction volume with a larger sectional area in a central portion than in both ends is defined in the suction muffler.

Abstract: A linear compressor is provided that includes a stationary member including a cylinder that provides a space to compress a refrigerant; a movable member that linearly reciprocates with respect to the stationary member, and that includes a piston that compresses the refrigerant inside the cylinder and a supporter piston having a support portion that extends in a radial direction of the piston; front main springs positioned so as to be symmetrical with respect to centers of the piston and the supporter piston, one ends of which are supported by a front surface of the support portion of the supporter piston and the other ends of which are supported by the stationary member; a rear main spring, one end of which is supported by a back surface of the supporter piston; a suction muffler that provides a passage to introduce the refrigerant while reciprocating with the movable member, reduces noise, and includes an extended part that extends toward the supporter piston; and a spring guide fixed to the supporter piston

Abstract: A linear compressor is provided in which a resonance frequency may be synchronized with an operating frequency. The linear compressor may include a fixed member including a cylinder, a movable member including a piston for compressing refrigerant in the cylinder, a center portion that coincides with the center of the piston, and a support that extends in a radial direction of the piston and linearly reciprocates about the fixed member, a plurality of front mainsprings arranged symmetrically about the center of the piston and each having one end supported on a front side of the support of the supporter and the other end supported on the fixed member, a single rear mainspring having one end supported on a rear side of the supporter and the other end supported on the fixed member, and a plurality of mass members coupled to a rear side of the supporter at a predetermined distance from the outer diameter of the rear mainspring.