Abstract: In a process for recycling of gas-containing synthetic plastics material, this material at first is comminuted, molten, degased and filtered. The degased synthetic plastics material is supplied in the same plant before its solidification for gas introduction, and in order to homogenize the gas content, the gas amount introduced into the synthetic plastics material per time unit is controlled in dependence from the synthetic plastics material amount supplied per time unit to the gas introduction, and preferably the pressure of the synthetic plastics material to which gas is to be added, is kept almost constant. The apparatus suitable for performing this process comprises an extruder (12,13) for plasticizing and degasing the synthetic plastics material, the outlet (15) thereof is connected by means of at least one line (16) to a mixer (25), to which also a device (29) for supplying gas is connected.

Abstract: An apparatus for plasticizing thermoplastic synthetic plastics material includes a screw (13) which rotates within a housing (12) and plasticizes the synthetic plastics material which is supplied by a supply mechanism (27) through an intake opening (10) of the housing (12) of the screw (13). The housing (12) of the screw (13) is provided on its inner wall with at least two wide pockets (23,24). These pockets (23,24) extend in longitudinal direction of the screw (13) and are separated from each other by ribs (25,26) which are narrow, when compared with the width of the pockets. One pocket (24) is open towards the intake opening (10), the other pockets (23) are closed by at least one rib (25,26) of the housing (12) of the screw (13) with respect to the intake opening (10). In order to improve filling of the screw (13), the supply mechanism (27) for the synthetic plastics material to be treated cooperates with the screw (13).

Abstract: An apparatus for granulating thermally unstable synthetic plastic material includes a tip-driven plasticizing screw positioned in a housing. The screw conveys the synthetic plastic material through exit openings in the housing, wherein granulating knives slidably engaged with the housing exit openings cut-off pellets of synthetic plastic material. The drive mechanism for the plasticizing screw is disposed at the exit opening side of the screw with the orbit of the granulating knives disposed between the exit openings and the drive mechanism. The drive shaft of the plasticizing screw is detachably coupled to the front, or exit, end of the screw. A conveyor blower cools the pellets as they are severed from the exit openings, and further operates to convey the pellets to a storage bin for packaging.

Abstract: An apparatus for degassing thermoplastic synthetic plastics material has a first screw section (11) for the intake of the material to be treated. The plasticized synthetic plastics material flows from the housing (10) of this screw section (11) through a connection channel (15) to a filter (16) and from there through an inflow opening (17) into the housing (18) of a second screw section (19) which conveys the material to an outlet (21). Between the two coaxial screw sections (11, 19), a sealing section (26) is disposed which avoids a by-pass of the filter (16). A baffle member (28) is disposed in front of the inflow opening (17) which forces the synthetic plastics material stream into a hose-formed shape. The baffle member (28) is displaceable with respect to the inflow opening (17) in axial direction and has a cross section which tapers towards the second screw section (19).

Abstract: A filter apparatus for thermoplastic synthetic plastics material melts comprises a housing (2) in which two filter disks (5,6) are disposed in parallel to each other and spaced apart from each other. The melt to be filtered is supplied to these filter disks (5,6) via an upstream channel (19). The impurities gathering on the upstream side of the filter disks (5,6) are continuously scraped off by a scraper (8) that carries a plurality of scraper elements (10) disposed along curved lines spaced apart from each other so that they convey the impurities towards the center of the filter disks (5,6). There, the impurities reach a conveyance channel (22) in which they are conveyed off by at least one worm (23,24).

Abstract: An input transformer for a coaxial transmission line is provided which allows continuously variable amplitude and phase of an RF signal conducted on the transmission line. The transformer comprises a housing having a longitudinal axis. A center conductor of the coaxial line extends along the axis through the housing. A first sleeve is axially movable within the housing, and has contact points on an outer surface thereof to provide electrical conductivity between the first sleeve and the housing. The ability of the first sleeve to move axially enables variability in the location of the transformer along the transmission line. The first sleeve has an inner wall that is eccentric relative to the longitudinal axis of the center conductor. A second sleeve having a cylindrical outer wall is disposed within the first sleeve. The second sleeve is rotationally movable within the first sleeve, and has contact points on the outer wall to provide electrical conductivity between the first sleeve and second sleeve.

Abstract: An apparatus for pre-treatment of thermoplastic synthetic plastics material, for example polyester waste, comprises at least two receptacles (1,13) disposed in series following each other, in each one of which receptacles a comminuting or mixing tool (5) rotates around a vertical axis (4) in the bottom region of the receptacle (1 or 13). At least the downstream receptacle has an evacuation line (18) through which, optionally also a protective gas can be introduced. The receptacles (1,13) are connected to each other by a tube piece (12) in which a shut-off means (20) is disposed so that the vacuum in the downstream receptacle (13) can be maintained without any problem until the shut-off valve (20) is opened, whereupon the vacuum in the receptacle (13) sucks on the material positioned in the upstream receptacle (1).

Abstract: An apparatus for plasticizing thermoplastic synthetic plastics material, in particular scrap material, comprises a plasticizing screw (18) bearingly supported within a housing (21), to which screw the synthetic plastics material to be plasticized is supplied through a feed opening (16). At this feed opening (16) a comminuting means in the form of two shafts (3, 4) disposed parallel to each other and parallel to the axis of the screw (18) is provided, each of the shafts (3, 4) being provided with a plurality of pinned-up disk-shaped comminuting tools (8). Between each two neighboring comminuting tools (8) a circular spacer disk (9) is disposed and stationary knives (11) engage into the gaps between adjoining comminuting tools (8), the flanks (15) of which knives extend tangentially with respect to the periphery (13) of the spacer disks (9).

Abstract: A filter apparatus for synthetic plastics material melts containing impurities comprises a housing (1) in which a cylindrical or conical filter element (3) is bearingly supported for rotation around its longitudinal axis (4) by a drive means (8). The outer periphery (15) of the filter element (3) is engaged by a scraper element (20) which surrounds the filter element (3) along a helix line or a spiral line. The material to be filtered is supplied from the outside through an inlet opening (12) to the filter element (3). The filtered material penetrates openings (18) of the filter element (3) and flows into a central hollow space (17) thereof wherefrom it is carried off through a discharge opening (18). The impurities cannot pass the opening (16), gather on the outer periphery (15) of the filter element (3) and are carried by the stillstanding scraper element (20) towards an exit (24). Thereby a reliable construction is achieved which requires less effort (FIG. 1).

Abstract: A microwave test fixture (10) for testing a two port microwave integrated circuit (MIC) (11) including a first signal block (12) and an opposing second signal block (14). Each signal block (12 and 14) includes an inside face (20 and 36) with an overhang portion (30 and 46), a vertical channel (52 and 62) and a connector aperture (70 and 72). The connector apertures (70 and 72) each receive a connector assembly (78 and 80) that includes a coaxial connector (82 and 108), a conductive sleeve (84 and 110) and an insulative bead (112 and 86). A signal contact (88 and 114) extends from an inner conductor 90 of each coaxial connector (82 and 108), through the insulative bead (112 and 86) and vertical channel (52 and 62) and out from the inside face (20 and 36) below the overhang portion (30 and 46). Each signal contact (88 and 114) includes a contact spring section (100).

Abstract: An apparatus for filtering and extruding plastic scrap consists of an extruder housing having an interior chamber and an extruder worm received and supported for axial rotation in the chamber. The extruder worm includes a centrally located set of return threads which divide the chamber into first and second chamber portions. The housing further includes an intake opening in the first chamber portion for receiving raw material, an exit opening in the second chamber portion for discharging filtered material, and a degassing opening in the second chamber portion for discharging gasses from the chamber. A drive mechanism is provided for rotating the extruder worm. A filter channel connects the first and second chamber portions wherein the plastic material passes from the first chamber portion to the second chamber portion through the channel. The channel has an inlet opening in the first chamber portion and an outlet opening in the second chamber portion.

Abstract: A filter apparatus for thermoplastic synthetic plastics material includes a screen carrier member having at least one screen nest, the screen carrier member being shiftable in a longitudinal direction in a housing. For backwashing the screen nest, the screen nest is in connection with a washing channel in a washing position of the screen carrier member In order to make the washing process quickly, effectively and uniformly over the surface of the screen and in order to avoid an additional loss of the mass in the main flow at the backwashing process, a storage space is provided in the screen carrier member which is filled in normal operation with cleaned melt. A piston in the storage space is shifted for moving the material provided in the storage space in the backwashing direction through the screen nest and into the washing channel.

Abstract: A filtration apparatus for thermoplastic synthetic plastics material comprises a housing (1) in which a carrier body (4) formed by a piston, for two screen nests (8,9) is bearingly supported for displacement in direction of its axis. In the filtration position the melt streams from a supply channel (2) via inflow channels (10 to 13) into distribution spaces (14,15) located in front of the screen nests (8,9), then through the screens and via outflow channels (18,19) into a discharge channel (3). Each distribution space (14,15) is subdivided by at least one wall (21) and into each of the so formed compartments terminates an inflow channel (10 to 13).

Abstract: A coaxial support structure (10) is provided to providing an interface and support for microwave transmission components. The preferred coaxial support structure (10) includes a hollow cylindrical outer conductor (12), a hollow cylindrical inner conductor (14) disposed coaxially therewithin, and a dielectric spacer (16) providing separation and mutual captivation. The dielectric spacer (16) has odd symmetry, preferably trilateral, and has an end gap (70) separating the spacer end surface (68) from the end planes (38) in which the respective end surfaces (36,50) of the conductors (12,14) are disposed. The inner conductor (14) is provided with spiral grooving (52) on its peripheral surface (46) to provide excellent captivation by the central tube portion (64) of the dielectric spacer (16) with minimal effect on the transmission. Optional features include threading (58) on the interior surface (48)of the inner conductor (14) and a dust washer (72) for disposal within the end gap (70).

Abstract: Apparatus and a method are disclosed for providing a microwave attenuator system using distributed (transmission line) reactive elements to achieve a reduction in the transmitted electrical signal amplitude. The attenuator system includes a fixed attenuator unit and an adjustable attenuator unit. The fixed attenuator unit contains a "T" resistive attenuator component. Transmission line resonator components are added to the attenuator component to provide frequency selectively. The transmission line resonator components are coupled to the resistive attenuator component in such a way as not to compromise the impedance match of the transmission line. The step adjustable loss component includes shunt transmission lines coupled to the center conductor of the transmission line by means of a spring contacting mechanism. The shunt transmission lines include preselected resistive elements.

Abstract: An apparatus for processing thermoplastic synthetic plastic material includes a receptacle in which a rotating tool circulates around an axis. The axis of rotation may be offset with respect to the axis of the receptacle by a predetermined amount. From the receptacle, the comminuted material is conveyed by the rotating tool into the inlet opening of a screw-type extruder which has an axis that is offset relative to a parallel radius of the receptacle. The offset arrangement allows the rotating tool improves the flow of the processed material into the screw-type extruder.

Abstract: A unitary three-vane support bead (30) detunes the lowest-frequency transverse cavity modes, forcing resonances toward higher frequencies. Its impedance, compared with that of prior solid beads, is closer to the impedance of an air line. The bead is injection-molded in place, with a radial boss (35) at the radially outer end of each vane (32). Three apertures (14) in the outer conductor (11) capture the bosses, for economical but secure mounting; in fabrication these three apertures serve as injection gates. On its end (29) facing a mating device (65, 65f), the central conductor (21) has an axial bore (26) that holds a cylindrical sheet-metal spring (50). The outward-facing edge (56) of this spring protrudes slightly from the bore and is trimmed to form three distinct contact areas (52), each of relatively small circumferential extent, for kinematically stable engagement with the mating-device central pin (65).

Abstract: A filter apparatus, particularly for filtering extruded thermoplastic synthetic plastics material, has a housing, within which two carrier members are shiftably arranged, each of which carries a sieve means consisting of two filter sieves. The material to be filtered is supplied to the entry side of the sieve means via an inlet passage. Within each carrier member there is provided a rinsing passage being in connection with the outlet side of the sieve means. The rinsing passage can be connected with the outlet passage when shifting the carrier member into a rinsing position. In this rinsing position, the entry side of the sieve means is at least partially connected with a space receiving the sieve contaminations or opens into atmopshere, respectively.

Abstract: According to the invention, a microstrip microwave frequency attenuator comprises a distributed series resistance medium and distributed shunt resistance medium, wherein the shunt resistance medium is disposed parallel to the direction established for electric fields in the microstrip between the signal path and ground through the energy supporting medium. In the preferred embodiment, the series resistance path has a resistance value per unit length equal to about one-third of the resistance value per unit length compared to the shunt resistance path between the series resistance path and the ground plane.

Abstract: Apparatus for processing synthetic thermoplastic material comprises a receiver having a vertical axis, a disintegrating and mixing tool which is disposed in the receiver near the bottom thereof and rotatable about the axis of the receiver, and at least one screw extruder, which extends through an opening in the shell of the receiver into the latter adjacent to the disintegrating and mixing tool. To ensure that the screw extruder can be filled uniformly and that such filling will be independent in a high degree from the level to which the receiver is filled, the screw extruder extends at least approximately radially of the axis of the receiver and that end of the screw extruder which extends into the receiver is axially spaced above the disintegrating and mixing tool.