Abstract: An air-cooled shaft seal comprises an annular body having an inner surface and an outer surface. One or more helical channels are formed on the inner surface. A plurality of external surfaces such as radial fins are disposed in axially spaced relationship on the outer surface, and extend radially in a direction away from a longitudinal axis of the annular body. The external surfaces present a substantially increased surface area through which heat energy is transferred from polymeric material contained in the seal to the atmosphere. The seal may be installed on one or shafts of a gear pump for transporting a viscous material under pressure.

Abstract: The invention relates to a modular cable guide system for use in an injection moulding apparatus including at least one first cable guide conduit, at least one connector having a sleeve for fitting around a first end of the first cable guide conduit, clamping means for tightening the sleeve around the first cable guide conduit for forming a clamping connection with the conduit and a coupling member for connecting the connector to a machine part or to another cable guide conduit, and a second cable guide conduit having a number of regularly spaced connecting holes for receiving coupling elements for connecting the second guide conduit to the machine part. The system according to the invention can be easily installed and can be made to the right size and placed into the right configurations upon installation.

Abstract: A journal bearing comprises a body having a central longitudinal axis, a cylindrical inner surface coaxially disposed around the longitudinal axis and defining an axial bore, and an outer surface including a peripheral planar section. A lateral face is disposed on an end of the body, and extends between the outer and inner surfaces of the body. A feed channel is formed in the lateral face at an acute angle with respect to the planar section and in an inward direction with respect to the axial bore. A first end of the feed channel communicates with the outer surface of the bearing at a location proximate to the planar section, and a second end of the feed channel communicates with the axial bore. A pocket is formed in the inner surface of the bearing in communication with the second end of the feed channel and extends along a substantially helical path from the lateral face of the bearing. At least a portion of the pocket has a width of greater magnitude than a corresponding depth of the portion.

Abstract: An air-cooled shaft seal comprises an annular body having an inner surface and an outer surface. One or more helical channels are formed on the inner surface. A plurality of external surfaces such as radial fins are disposed in axially spaced relationship on the outer surface, and extend radially in a direction away from a longitudinal axis of the annular body. The external surfaces present a substantially increased surface area through which heat energy is transferred from polymeric material contained in the seal to the atmosphere. The seal may be installed on one or shafts of a gear pump for transporting a viscous material under pressure.

Abstract: The present invention includes a filtration apparatus for an injection molding machine where the injection molding machine includes a screw housed within a bore for generating molten polymer. A tip member extends axially from the screw. The tip member has radially extending upstream and downstream flanges positioned axially apart from each other. A filter encircles the tip member and is capable of filtering the molten polymer. An annular ring member encircles the tip member and is slidably positioned within the bore between the upstream and downstream flanges. The ring member is capable of sliding between the flanges for directing the molten polymer through the filter or preventing back flow of the molten polymer past the upstream flange.

Abstract: A coinjection molding system for injecting skin and core material into a mold cavity. The system includes a three position actuator for moving a valve pin into a closed position in which neither skin nor core flow is permitted, a middle position in which only skin flow is permitted, and an open position in which skin and core flow is permitted. The actuator includes a first piston slidably mounted in an actuator housing, and a second piston, attached to the valve pin, slidably mounted within the first piston. A shut-off is provided in the manifold for preventing skin flow to a particular nozzle during sequential gating.

Abstract: An injection molding nozzle for disposition in a mold. The nozzle is for injecting melt into a cavity of the mold, and includes a body having a through bore extending therethrough for receiving the melt. Attached to the body of the nozzle is a nozzle piece secured to the body that defines an outlet communicating between the body through bore and the cavity gate. A nozzle member surrounds the body at a position upstream of the nozzle piece and has an inner surface contacting the body, and an outer surface contacting the mold. The outer surface forms a seal against melt flow upstream from the nozzle member.

Abstract: A valve gated injection molding system to facilitate improved melt flow to the gate of the nozzle. The system includes an annular flow insert through which the valve pin passes. The annular flow insert includes an annular groove on its outer surface. The edge of the annular groove is spaced from the wall of the melt channel so that some of the melt can flow longitudinally between the edge of the groove and the wall, while the remainder of the melt flows in the groove. The flow direction initiated by the annular flow insert eliminates flow separation and dead spots about the valve pin. The system also includes an actuator assembly including a sled attached to the valve pin.

Abstract: A valve gated injection molding system to facilitate improved melt flow to the gate of the nozzle. The system includes an annular flow insert through which the valve pin passes. The annular flow insert includes an annular groove on its outer surface. The edge of the annular groove is spaced from the wall of the melt channel so that some of the melt can flow longitudinally between the edge of the groove and the wall, while the remainder of the melt flows in the groove. The flow direction initiated by the annular flow insert eliminates flow separation and dead spots about the valve pin. The system also includes an actuator assembly including a sled attached to the valve pin.

Abstract: An injection molding nozzle for disposition in a mold. The nozzle is for injecting melt into a cavity of the mold, and includes a body having a through bore extending therethrough for receiving the melt. Attached to the body of the nozzle is a nozzle piece secured to the body that defines an outlet communicating between the body through bore and the cavity gate. A nozzle member surrounds the body at a position upstream of the nozzle piece and has an inner surface contacting the body, and an outer surface contacting the mold. The outer surface forms a seal against melt flow upstream from the nozzle member.

Abstract: An in-line pressure transducer includes a body and an inner ring, coupled to the body, through which molten material flows. The inner ring expands in response to pressure from the molten material. An outer ring is located coaxially with the inner ring. At least one flexure connects the inner and outer rings. The flexures translate expansion of the inner ring to the outer ring. The body includes a cavity within which the outer ring is located. The cavity preferably has a cross-sectional shape that is trapezoidal in order to compensate for lateral displacement of the transducer in response to axial forces exerted thereon during operation.

Abstract: A pressure transducer for an injection molding machine includes a housing coupled to a nozzle of an injection molding machine. A hollow stress tube, attached to the housing, through which molten material of the injection molding machine flows, bellows in response to pressure from the material. An outer ring having an opening is coupled to the stress tube such that the outer ring expands, causing displacement of the outer ring about the opening, when the stress tube bellows. A displacement sensor is included for determining the displacement of the outer ring about the opening. This displacement is directly proportional to the pressure of the material. In this manner, the pressure transducer determines the pressure of the molten material.

Abstract: A capillary rheometer apparatus includes a housing, a plunger, the housing having a reservoir for receiving the plunger in a polymer melt, and a mechanism for blocking flow of the melt out of the reservoir. A driving mechanism is included for driving the plunger longitudinally within the reservoir to move one end of the plunger in contact with the melt. A diaphragm, which is coupled to the one end of the plunger, deflects in response to melt pressure in the reservoir. A mechanism, responsive to diaphragm deflection, determines pressure of the melt. Another mechanism is included for determining the temperature of the melt and a further mechanism is included for indicating longitudinal movement of the plunger. From such determinations, the PVT characteristics and the apparent shear viscosity characteristics of the polymer melt can be obtained.

Abstract: A pressure transducer for an injection molding machine includes a housing coupled to a nozzle of an injection molding machine. A hollow stress tube, attached to the housing, through which molten material of the injection molding machine flows, bellows in response to pressure from the material. An outer ring having an opening is coupled to the stress tube such that the outer ring expands, causing displacement of the outer ring about the opening, when the stress tube bellows. A displacement sensor is included for determining the displacement of the outer ring about the opening. This displacement is directly proportional to the pressure of the material. In this manner, the pressure transducer determines the pressure of the molten material.

Abstract: An optical pressure transducer includes a body for supporting therein both an input optical fiber and an output optical fiber. A light source generates input light to the input optical fiber. A force responsive diaphragm is secured to the body and deflects in response to sensed pressure. A fixed reflector and a moveable reflector, which is attached to and moves with the diaphragm, are disposed in the optical path between the input and output optical fibers and reflect at least a portion of the input light from the input optical fiber to the output optical fiber. The amount of light reflected depends upon the deflection of the diaphragm. A system for monitoring and controlling the light source, including an optical detector in a feedback arrangement, is provided such that the amount of light generated by the light source remains constant and maximized.

Abstract: A capillary rheometer apparatus includes a housing, a plunger, the housing having a reservoir for receiving the plunger in a polymer melt, and a mechanism for blocking flow of the melt out of the reservoir. A driving mechanism is included for driving the plunger longitudinally within the reservoir to move one end of the plunger in contact with the melt. A diaphragm, which is coupled to the one end of the plunger, deflects in response to melt pressure in the reservoir. A mechanism, responsive to diaphragm deflection, determines pressure of the melt. Another mechanism is included for determining the temperature of the melt and a further mechanism is included for indicating longitudinal movement of the plunger. From such determinations, the PVT characteristics and the apparent shear viscosity characteristics of the polymer melt can be obtained.

Abstract: An optical pressure transducer includes a body for supporting therein both an input optical fiber and an output optical fiber. A light source generates input light to the input optical fiber. A force responsive diaphragm is secured to the body and deflects in response to sensed pressure. A fixed reflector and a moveable reflector, which is attached to and moves with the diaphragm, are disposed in the optical path between the input and output optical fibers and reflect at least a portion of the input light from the input optical fiber to the output optical fiber. The amount of light reflected depends upon the deflection of the diaphragm. A system for monitoring and controlling the light source, including an optical detector in a feedback arrangement, is provided such that the amount of light generated by the light source remains constant and maximized.

Abstract: A capillary rheometer plunger having a liquid-filled capillary passage extending within the plunger is removably housed in a heater block holder for maintaining temperature stability and minimizing temperature induced errors. The plunger is placed in the holder during purging, cleaning, reloading and packing the capillary rheometer with the polymer under test. The holder includes an electrically heated holder member disposed within an aperture of an outer shield and is provided with an aperture in which the plunger is removably received for heating. A base supports the shell. A temperature sensor disposed in the shell controls the temperature of the holder member at the temperature of the polymer under test.

Abstract: A capillary rheometer including a plunger pressure transducer assembly which contains a liquid metal fill capillary passage therein. When the plunger is urged downward onto the melted polymer, a diaphragm at the end of the plunger senses the pressure within the melted polymer and transmits this pressure to the liquid metal fill. An additional diaphragm disposed in the opposite end of the plunger pressure transducer assembly senses this transmitted pressure within the liquid metal fill for an accurate indication of the pressure therein.

Abstract: An optical pressure transducer employing input and output optical fibers defining therebetween an optical path. The optical path is interrupted by a fixed reflector and a moveable reflector. The moveable reflector is secured by adjustment means to the diaphragm that is responsive to pressure being measured.