Showing papers by "Weingarten Realty Investors published in 1992"

Mechanical resonance gas sensors with piezoelectric excitation and detection using PVDF polymer foils

Abstract: A simple mechanical resonator sensor fabricated out of a glass plate acting as a vibrating cantilever beam and interrogated with piezoelectric PVDF polymer foils glued on both sides of the plate is described and characterized with respect to gas-sensing applications. The sensitivity of this device allows binary gas mixtures to be controlled at an accuracy level of a few percent, which can be enhanced by the mode-coupling effect, i.e., the coupling of flexural and torsional vibrations neighbouring in resonance frequency.

Luggage carrier for motor vehicle - consists of pull-out platform in/or rear bumper assembly

Abstract: A platform (11) is located at the rear of the vehicle (2), in the area of the rear bumper (4). It is hidden, can be moved into a horizontal position, and supported to carry luggage. The platform is formed by a pull-out part of the bumper. The platform has carrier bars, which are moved backwards out of the bumper. The bumper (10) is fastened to the back of the carrier bars. A cover plate (18) may move with the platform, or may be placed on it. The platform also has a separate removable plate, which is supported on the bumper and/or the rear of the vehicle, when in use. There is a fold- down ramp, and a bracket (16), to retain luggage. USE/ADVANTAGE - Is of good appearance, can be brought into action easily, for transportation of e.g. bicycles, is always available, and does not impair appearance of vehicle.

Occurrence of quinolone resistance in Staphylococcus aureus from nosocomial infection.

Abstract: Among 63 Staphylococcus aureus isolates (one isolate per one patient) counted from infections (from August to November 1991) in hospital T., eight exhibited resistance to fluoroquinolones. Seven of these quinolone-resistant isolates were multiply- and methicillin-resistant S. aureus (QR-MRSA). The results of phage-, plasmid- and genotyping (pulsed field electrophoresis) revealed that six different strain-clones of these MRSA were spread in the hospital. In vitro spontaneous mutants resistant to fluoroquinolones are 10-100-fold more frequent in MRSA than in other S. aureus when selected on isosensitest-agar containing 1 microgram/ml of ciprofloxacin. However, the same mutant frequencies were found in strain 8325-4 with and without the mecA-determinant. The resistance phenotype was stable over 30 generations of subculture in nutrient broth as well in natural quinolone resistant MRSA as in mutants of other types of S. aureus selected in vitro. The phenotypic association of quinolone resistance and MRSA is rather likely due to a higher frequency of spontaneous resistant mutants which are present in natural populations of MRSA. Data of chemotherapy prior to the isolation of S. aureus show that three of seven patients from whom QR-MRSA were isolated were treated with a quinolone. In eight cases of infections with non-MRSA and quinolone treatment the isolated S. aureus strains were in vitro sensitive to quinolones.

Compact passenger or goods vehicle with speed-dependent impact cushion - carries air bags mounted fore and aft on extension chassis and inflated progressively during acceleration from rest

Abstract: The vehicle floor is formed by the upper surfaces of two interlocked chassis sections (3,4) with the propulsion unit enclosed pref. in the forward section (3). Front and rear crash protection (10,11) is provided by impact shields (15) deployed along variable guides (17) around air bags (16). The deg. of inflation and deployment are adjusted automatically in proportion to rod speed. Frontal impact pushes back the shield and displaces air into a sec. air bag folded into the steering wheel. ADVANTAGE - Entire floor area can be utilised with improved crash protection relying less upon bodywork, which can be assembled from individually replaceable modular components.

Housing for sliding vane closure - has wear-resistant bush of two symmetrical parts, surrounded by outer elastomer flange

Abstract: The sliding vane air lock for loose material has a rotor (5) mounted in a housing (2) which has an inlet and an outlet duct. The rotor is supported at each end in bearings (10) mounted in the end covers (1) of the housing. - A wear-resistant bush (12) is fitted between each end of the rotor and its adjacent end cover. The bush has an axially projecting flange (15) which is fitted with a ring (16) of elastomeric material which allows the bush to ''float'' radially w.r.t. the housing.

Is physics worth teaching

Abstract: The paper points out that many students and adults are accustomed to solving problems in physics on the basis of everyday concepts; believing that these concepts are very successful, those students are not interested in concepts offered by science teaching. Furthermore, the teaching physics in terms of mathematical descriptions of problems is too early — students don't see the original problem, so they are not interested in solutions. One way to avoid these difficulties is M. Wagenschein's proposal of the ‘Exemplary-genetic Method’. This method and its principles are presented and illustrated with examples taken from history. On the basis of this method educational and pedagogical functions of teaching physics are developed. P.S.: Martin Wagenschein (1896–1989), Professor of physics education at the University of Tubingen, was concerned with finding new methods for successfully teaching science.

Modular structure of car trailer - has bottom shell holding and guide members on its top longitudinal edges.

Abstract: The trailer structure has self-supporting parts (10-18) with counter-holding and guide members (48) at their lower longitudinal edges for coupling to the holding and guide members (44, 46) of the bottom shell (2). To the latter is inserted a front part (6) for fast connection to the adjacent structure parts (19. 18). A rear portion (8) with an integral rear door (9) is inserted onto the bottom shell for fast connection to the adjacent structure part (10, 12). Pref. the holding, counter-holding, and guide members have undercut grooves and keys on the respective bars at the longitudinal edges of the bottom shell and structure parts. ADVANTAGE - Wide applicability, small number of components permitting wide structural variations.

Mechanical press overload protection system

Abstract: The mechanical press head has its crankshaft connected to several pistons (5), which operate in hydraulic cylinders (7). An upward force (Fv) can be exerted on each piston by the pressure of hydraulic fluid from a pump (10), driven by a motor (M). The space in each cylinder below the piston is connected to a pressure overload valve (15) which has a stepped piston (16). The smaller piston dia. (17) is acted on by the pressure in the hydraulic cylinder (1,2), with the larger piston dia. (18) connected directly to the pump. On an unequal load on the press ram, the pressure in the corresp. cylinder is increased and acts on the smaller dia. The valve is open, when the pressure on the underside of the piston exceeds the pressure on its upper side by a given ratio.

Die casting machine

Abstract: In a die-casting machine for producing castings from metals or metal alloys, which castings have a low content of gas, pores and oxides, melt is drawn by means of a vacuum out of a holding device (10) via a suction tube (11) into a casting chamber (3). A casting plunger (7) closes the inlet opening (16) to the casting chamber (3). In order to achieve as low as possible mechanical surface pressure due to flow of the melt, and fluviatile erosion of the die-side end of the inlet opening (16), and thus avoid high wear of this inlet edge or of the casting chamber with casting plunger, a planar or linear inlet cross-section (24, 27) as well as a curved deflection surface (20) on the casting plunger (7) are provided.

Verfahren zur Ermittlung unzulässiger Abweichungen von Verfahrensparametern

Abstract: Ausgehend von einem Verfahren zur Ermittlung unzulassiger Abweichungen von Verfahrensparametern insbesondere bei Druckgiesmaschinen oder dgl. wird ein Verfahren vorgeschlagen, bei dem aus der Ermittlung der genauen Werte von Verfahrensparametern bei der Herstellung einer bestimmten Anzahl von Referenzteilen, die in herkommlicher Weise einer Qualitatsprufung unterzogen werden, auf die Qualitat der anschliesend hergestellten Teile ohne weitere Qualitatsprufung ruckgeschlossen werden kann. Es werden somit Auswahlkriterien zur Erkennung von Ausschusteilen geschaffen, die den Aufwand und die damit verbundenen Kosten der Qualitatsprufung der in solchen Verfahren hergestellten Teile deutlich reduzieren.

Pressure diecasting machine feed

Abstract: The proposal is for a metering and loading device for pressure casting machines which is used in a cold chamber pressure casting machine to transport the metal melt between a heat retention device and the casting chamber of the machine. In order to determine the precise weight or the volume determinable therefrom of the metal melt to be taken to the casting chamber, there is an additional weighing device (22, 22') which is either allocated directly to the metering ladle (9) or finds the weight of the metal melt via a separate intermediate or preliminary container (23).

Mounting device for insulating glazing

Abstract: A mounting device (11) for insulating glazing (4) is designed in the form of a two-legged angle piece which lies on and/or bears against the casement (3) receiving the insulating glazing (4) and has, to support the outer glazing (5), a receiving pocket (14) surrounding the edge of the latter. As a result of this design of the mounting device, it is possible to support both the glazings (5, 6) individually and a secure locking of the insulating glazing (4) in the lateral direction is also afforded. Moreover, mounting of the insulating glazing (4) is also made considerably easier and quicker.

Vorrichtung zum pneumatischen Fördern von Schüttgut

Abstract: Beschrieben wird eine Vorrichtung zum pneumatischen Fordern von Schuttgut mit einer Forderleitung (5) fur das Schuttgut (2) und mit einer parallel dazu verlaufenden Begleitleitung (10), die beide an dieselbe Druckluftquelle angeschlossen sind, so das in beiden Leitungen eingangs derselbe Druck herrscht. Von der Begleitleitung (10) gehen Zweigleitungen (12 bis 15) ab, die in federbelasteten Uberstromventilen (20 bis 25) munden, die an vorgegebenen Stellen langs der Forderleitung (5) vorgesehen sind. Bilden sich in der Forderleitung (5) ein Stopfen (16) des Fordergutes (2), so offnen die Uberstromventile (20 bis 25) und blasen dadurch die Forderleitung (5) frei. Erfindungsgemas sind die Federkrafte der Uberstromventile (20 bis 25) auf vorbestimmte Werte eingestellt, so das die Vorrichtung storungsfrei arbeitet. Anstelle von mit Druckluft kann auch mit Saugluft gearbeitet werden.

Pipe switch for pneumatically conveyed bulk materials

Abstract: A pipe switch for bulk materials to be conveyed pneumatically is described, in which a rotor with a rotor pipe is arranged in a stator with pipe outlets and in which the rotor has a sealing effect in relation to the stator. In order to achieve the necessary sealing effect, it is provided that the rotor or the stator have a jacket made of plastic material, the parts provided with the plastic material being either entirely of plastic or a combination of metal and plastic.

Assembly for continual mixing of powdery or coarse-grained bulk solids - has cylindrical or prism-shaped mixing container which separates ingredients into flow for recirculation etc. and flow for removal

Abstract: Assembly consists of a large cylindrical or prism-shaped mixing container narrowing to a funnel at the base, at the centre of which a central pipe conveys dried products from the bottom upwards for mixing by recirculation The novelty is that the descending flow of ingredients is divided into two, one of which is recirculated and further mixed, and the other is removed from the mixer Pref powder or coarse grained bulk solids brought together in a bulk mixing container descend to the funnel-shaped base where the flow (M1) is divded into two (M2, M3) One flow (M2) is returned to the top of the container by a pipe (17) while the remainder of the solid flow (M3) is drawn off through a removal unit (18) USE/ADVANTAGE - The assembly mixes powdery or coarse grained bulk solids The assembly has the advantage that it integrates the processes of filling, mixing and removal of the mixed products such that these processes may be combined or not as required This saves time and facilitates continuous operation

Method of controlling casting parameters in a diecasting machine

Abstract: Casting parameters in at least one of a feeding and mold-filling and squeezing phase are controlled during a casting step in a cold-chamber die-casting machine. The casting parameters are controllable as a function of travel of a casting piston longitudinally displaceable in a shot sleeve. The quantity of molten metal filled in within the shot sleeve is determined by precise metering using a stationary optical measuring device. The metering is accomplished by beaming a measuring beam through a filling port of the shot sleeve and reflecting the measuring beam on a surface of the molten metal. The transit time of the measuring beam and the reflected beam are measured to determine a filling level and quantity of molten metal filled in. A control system is provided which controls a movement of the casting piston and a start of each phase as a function of the filling level and the associated quantity of molten metal filled in.

Multifunction key switch for stimulation current unit for medical bathing - ensures that after switch on and acceleration of intensity no acceleration of switch position is possible at board using shielding cover

Abstract: The multifunction key switch consists of a safety lock (8), with spring mounting, fixed at the switchboard (2). A rotary knob (4) is located in the cover (3) fo the stimulating current machine, allowing rotation and pref. only small axial movement. Pref. a pointer marking and a safety key (5) are fitted adjustable in the centre axis of the rotary knob (4), which can be protected against removal and adjustment. One or more microswitches (13) are provided for controlling switching elements e.g. relays or electronic units, which can be operated using one or more cams (6) at the lock cylinder. Emergency stopping of the machine is achieved by pressing the rotary knob and making pref. small axial working stroke against loading of a spring. The safety lock works in conjunction with coupling and pressure ring via a spring contact switch for the emergency off-switch. Also included are inductive transmitter(s), Hall transmitter(s), reed contact(s), sensor contact(s), sensor field proximity switches for connecting to penumatic, magnetic/opto-electronic couplings for the safety lock cylinder operated in radial and axial directons. USE/ADVANTAGE - Prevents alteration in switch position leading to adverse effect on patients. Lock protected against false operation of machine and fault manipulation. Prevents use by non-autorized personnel. Operating faults automatically prevented.

Method of determining unacceptable deviations from process parameters

Abstract: A computer implemented method of determining unacceptable deviations from process parameters associated with manufactured parts, for use with die-casting machines. The method includes entering in a data base empirically determined parameter values for the manufacture of good parts, constantly acquiring during a preproduction phase actual manufacturing parameter values as a set of parameters for each of a predetermined number of manufactured parts, testing the quality of the predetermined number of parts produced during the preproduction phase, classifying the acquired sets of parameters for each preproduction phase manufactured part as good or reject based on the testing, and storing the classified acquired sets of parameters for each preproduction phase manufactured part. Reject parts arising in a subsequent production phase are determined without quality inspection thereof by constantly acquiring during the production phase actual manufacturing parameter values as a set of parameters for each production phase manufactured part, and comparing acquired sets of parameters for each production phase manufactured part with the classified acquired sets of parameters for each preproduction phase manufactured part.

Sliding vane closure with gas seals

Abstract: The sliding vane air lock forms a closure, through which the loose material flows into a transport system. The air lock has a housing (1) with an inlet funnel and a rotor with sliding vanes (9) enclosed in the housing. A seal (17) is fitted between each end of the rotor and the corresponding inner face of the housing end wall. The seal is mounted on a bearing (16) on the rotor shaft (5) so that it can rotate relative to the rotor.

Untersuchungen über die Festigkeiten von Verklebungen mit reaktiven PUR-Schmelzklebstoffen

Abstract: Reaktive PUR-Schmelzklebstoffe harten durch Erstarren des Schmelzklebstoffes sehr schnell aus. Durch eine nachfolgende chemische Nachhartung verbessern sich zusatzlich die Fugeneigenschaften. Dies fordert die Festigkeiten, die Warme- und Kaltebestandigkeit sowie die Bestandigkeit gegenuber Feuchte. In umfangreichen Versuchsreihen konnten die spezifischen Eigenschaften verschiedener PUR-SK-Typen aufgezeigt werden.

Sealing sleeve for two mutually sliding surfaces - has two shanks extending upwards to surface to be sealed,and transverse strap in top region

Abstract: The sealing sleeve(4) has two shanks(7, 8)extending upwards towards the surface to be sealed.The shank (8) away from the pressure side (11) has a moulded cross web (13) in the top part of the seal with a lower, largest possible pressure biasing surface (15) pointing into a hollow chamber (10) of the seal. The pressure biasing surface exerts a pressure force (18) on an upward sealing edge or sealing lip (19), whilst the shank(7) facing the pressure side extends up to or nearly to the machine part (3) which is to be sealed. USE/ADVANTAGE - For machine part packing seals.with differential pressure acting directly on the sealing lip.

Adjustment device for rotary plug in branch pipe join - has pneumatic or hydraulic lift cylinder with linear movement driving the shaft of the plug

Abstract: An entrainment drive (32) comprising two rotary entrainment discs (33, 36) and acting in one rotary direction is provided between the lift cylinder (20) and the rotary plug drive shaft (18). The first entrainment disc (33) can be driven by the lift cylinder (20) and has grooves (34, 36) or corresponding bores whilst the second disc (36) connected to the plug drive shaft (18) has at least one entrainment bolt (41) positively engaging in the grooves. The angle between the grooves corresponds exactly to the angle between the individual pipe branches of the join. USE - An extremely accurate displacement of the plug between the individual connecting pipes independent of the operating conditions.

Camper vehicle with high roof - includes system for extending roof a front and rear

Abstract: The vehicle is for transport and camping purposes. It has a high roof which can be extended on rails or rollers as required to provide extra roof space. The high roof (1) has an extendable alcove (2) at the front end and an extendable rear section (3). USE/ADVANTAGE - Providing extra space to accommodate a double bed in a camper vehicle.

Tool for cutting acrylic optical fibre - comprises soldering iron with notch for stripping off coating and blade for cutting at different distances from heater for different temps.

Abstract: A tool for dressing the ends of plastic optical fibres consists of a soldering iron and a perforated groove. The soldering iron has a polished cutting edge at high temp. to smoothly fuse the fibres and a conical groove at lower temp. to form an annular notch in the protective coating on the fibres; the drop in temp. between these two features is produced by the shape of the tool and by the different distances between the heating coil in the iron and the cutting edge or groove. ADVANTAGE - The tool replaces a mechanical method by a thermal means. It takes only 30 secs. at most to make fibre joins which have an absorption effect of only 2.5 dB, which are perfectly smooth and are little affected by vibrations or pollution.

Programmable claw for a robot - Has computer, servo controller and amplifier integrated in claw, with circuitry inside housing connected by multi-pin plug

Abstract: A freely programmable claw for a robot has computer (10), a servo controller and an amplifier (17) integrated within the claw for its electronic control. The major part of the circuitry and components are housed in a closed unit, connected to the claw by a multi-pin plug. The weight of the claw is 3 kg at the most. The claw is attached to the robot at a flange (1). There is a rotary mount (5) moving about an axis (6) and carrying six or seven suction fingers (7). There are also vacuum and force sensors. ADVANTAGE - Flexible in use and improved reliability.

Method for detecting inadmissible deviations of procedure parameters

Abstract: On the basis of a method for determining inadmissible deviations of process parameters, in particular in the case of die-casting machines or the like, a method is proposed in which, by determining the exact values of process parameters during the production of a certain number of reference parts, which are subjected in the conventional way to quality testing, it is possible to conclude the quality of the subsequently produced parts without further quality testing. Subsequently, selection criteria for detecting reject parts are created, reducing considerably the expenditure and associated costs of quality testing of the parts produced in such processes.