Abstract: A control circuit comprises a TRIAC (T) in series with the stator winding (1) of the motor across the terminals of an alternating voltage source (V.sub.M). A fixed sensor (H) is associated with the rotor (R) and operable to provide a signal indicative of the magnetic polarity of the part of the rotor (R) facing it. A diode circuit (DC) including at least one Zener diode supplies the sensor (H) and provides a signal indicative of the polarity of the alternating supply voltage (V.sub.M). A driver circuit (PC) is connected to the sensor (H) and to the diode circuit (DC) and pilots the control input (g) of the TRIAC (T) in a predetermined manner in dependence on the instantaneous position of the rotor (R) and the polarity of the supply voltage (V.sub.M).

Abstract: This method consists in supplying the various rooms of the premises with air under stable low pressure using a relatively high-pressure fan, in feeding the fan, on the one hand, using fresh air, and, on the other hand, using recycled air, that is to say air that has been displaced by the fan and not let into the premises, and in regulating the respective proportions of fresh air and recycled air so that the proportion of fresh air increases and the proportion of recycled air decreases when the ventilation requirements increase, and so that the proportion of fresh air decreases and the proportion of recycled air increases when the ventilation requirements decrease, so that the delivery rate of the fan is kept almost constant.Application to systems for controlled mechanical ventilation of premises.

Abstract: An induction cooking heater includes at least one inductor, a high-frequency current generator and a magnetic circuit located beneath the inductor. The reluctance of the magnetic circuit is calibrated so that the magnetic circuit gets saturated from a predetermined temperature lower than the maximum permissible temperature for the inductor. A plate made of non-magnetic, electrically conductive material located beneath the magnetic circuit, gives rise to an increase in current in the inductor when the magnetic circuit starts getting saturated. The generator is then controlled by a regulator for limiting the value of the current in the inductor to deliver lower power to the inductor.

Abstract: Syringe consisting of a body in which is disposed a piston (2) of the kind including at least two racks (53, 54) fitting onto the body and at least one lug carried by the piston (2), each of the racks being capable of being shifted in a single direction in relation to a lug. According to the invention, the syringe includes two lugs (63, 64) carried by a yoke (6) which straddles the piston (2), and is rotatably movable about the piston's axis. The lugs (63, 64) are driven into translation by the piston (2) while rotating freely in relation to the latter.

Abstract: A power tool, which is preferably configured as a right-angle grinder, has a motor-driven hollow spindle to drive a tool, which is fastened between a clamping flange and a counterflange by means of a quick clamping device via a tension spindle, coaxial with the hollow spindle, that is tensioned in the axial direction by means of elastic elements and is displaceable in the axial direction relative to the hollow spindle, by means of a clamping lever, between a clamped position in which the tool is nonrotatably retained between the flanges, and a released position. The clamping lever is mechanically coupled to the motor switch by means of a link rod in such a way that the clamping lever can be moved into the released position only when the motor is switched off. This rules out improper operation and any potential damage to the power tool.

Abstract: A device which makes it possible to remove a needle from a syringe very easily and safely. The device comprises a supporter, a syringe barrel receiver attached to the supporter slidably in the axial direction of the syringe, a rotatable member or members having a needle remover for removing the needle from the syringe, the rotatable member or members being attached to the supporter rotatably in the direction of removing the needle from the syringe, the rotatable member or members further having a spring for keeping the rotatable member or members in contact with a portion of the syringe barrel receiver and for returning the rotatable member or members and the syringe barrel receiver respectively to their original positions.

Abstract: An improved articulated bed with linearly retractable head and foot sections for easier shipment in a relatively small container that may be assembled by the purchaser without any tools. The bed includes a central frame with telescopic head and foot sections that linearly retract into the central frame. The central frame houses the head and foot drive motors, linear actuators, and rocker shafts that pivot mattress support panels upwardly from the extended frame.

Abstract: An articulated bed having a modified standard bed frame that supports an independent power module, replaceable without disassembly from the frame. The modified frame is the well known horizontally collapsible angle iron frame type with castered legs. The frame includes a pair of side rails each having head and foot rail portions pivotally connected at their ends for packing and shipping, that interengaged one another when assembled in the home. The modification in the frame is that the side rails are inverted and the legs are somewhat lengthened to accommodate the power module. After the frame is assembled in the home, a pair of "U" shaped cross members is attached across the frame and the power module fixed to the tops of the cross members. Then a folded for shipping mattress support assembly is unfolded and attached to the top of the frame over the power module.

Abstract: An amplifier sequence and a silencer sequence of the GPIIb promoter are disclosed. The amplifier sequence includes sequence domains (I) and (II), and the silencer sequence includes sequence domain (III). The use of these sequences in genetic engineering is also described.

Abstract: An apparatus for the infusion of a liquid contained in an infusion bag. The apparatus includes a plate for receiving an infusion bag, and a box having a closable lid. Interaction between the lid, the plate and an elastic spring mechanism located inside the box results in the expulsion of fluid from the infusion bag. The elastic spring mechanism includes four arms that articulate in pairs to form two cross structures that are biased together with springs. Respective ends of the two cross structures are connected by rollers, while opposing ends of the two cross structures are connected to inside portions of the box.

Abstract: A saw blade possesses a base element onto which boron nitride particles are applied in the cutting region. The boron nitride particles are bonded by means of a metallic bonding layer, which preferably consists of nickel or a nickel alloy with a Vickers hardness of at least 600 HV. The bonding layer is preferably deposited galvanically. The boron nitride particles advantageously possess a particle size of approximately 0.5 to 0.8 mm, preferably approximately 0.6 to 0.7 mm. The saw blade possesses particular advantages for use as a reciprocating saw blade for sawing GGG cast iron pipes with a cement lining and fiber-reinforced cement jacket, resulting in considerably improved cutting performance and service life.

Abstract: A linear drive for articulated furniture having pre-determined extended and retracted positions. These devices heretofore have been designed to be adjustable, but customer adjustment frequently causes costly damage to the drive and furniture. The drive includes a motor-driven rotary screw and a cooperating nut carrying drive tube which is rotationally fixed to a drive housing to prevent customer adjustment.

Abstract: A method for adjusting an opening cross section of an air inlet into a premises involves sensing the amount of water vapor contained in the air inside of the premises and the amount of water vapor in the air outside of the premises. The opening cross section is adjusted on the basis of at least one of a difference between the amount of water vapor sensed the inside and outside the premises so that the opening cross section increases when the difference increases and independently of the amount of water vapor in the air outside the premises. A device for adjusting an opening cross section of an air inlet into a premises includes two chambers in communication respectively with the air outside and with the air inside the premises, the chambers being separated from one another by a heat exchanger, which is impervious to water vapor.

Abstract: The present invention relates to a machine frame, and particularly but not exclusively, to a machine frame for so-called coordinate measuring machines of the kind which include at least one first portal that includes two parallel, vertical first and second legs (7, 8) which are rotationally and flexurally rigid in relation to a base member (10). The legs support a horizontal beam (11) on which there is movably supported a rod, bar or the like for supporting a measuring head, tool or corresponding device. The horizontal beam (11) is connected to the first leg (8) by a pivot joint (13) which permits the beam (11) to rotate in the vertical plane of the legs (7, 8), and is connected to the second leg (7) by a connection (14) which permits the beam (11) to rotate in this vertical plane and also to move in the direction of its longitudinal axis in relation to the second leg. The invention also relates to a method of determining the geometry of the portal occasioned by deformation of such machine frames.

Abstract: Housing (1, 20) for lodging conventional flat keys or keys of a special kind (2, 2a, 2b'-2b", 2c, 2d), in a safe but removable way. The laminar housing (1, 20) is realized by elastically flexible plastic material s of a type and form like a rectangular "credit card", and it is provided with a central opening (5, 21) whose peripheral edge (10, 22) defines a space for lodging a key or more superimposed keys. At the site of the opening (5, 21), elastic seizing elements (7--7) may project out of the housing (1, 20) acting on the lateral fins of the heads (3, 3a, 3b, 3c) or on the stems (4, 4a, 4c, 4d) of the keys.

Abstract: A Metal Detector with windings placed so as to originate multipolar electromagnetic fields, including two or more pairs of transmitter Tx and Receiver Rx windings, in which the different pairs are characterized by having a different number of poles so that the simultaneous passage of two or more metal masses on parallel trajectories will never cause equal and opposite inducted signals in the Rx windings, with a zero resultant so that such masses are detected in any case.

Abstract: A storable seat includes a seat base, a support member for supporting the base in a first plane above and generally parallel to a floor, a sliding assembly connected to the support member and the base and permitting the base to slide relative to the support member in the first plane, and a pivoting assembly connected to the support member and the base and permitting the base to pivot from the first plane to a second plane substantially perpendicular to the first plane. A seat back is pivotably connected to the base at a hinge point and locked in a fixed position, and a pivotable leg is pivotably connected to the base. The seat can be easily stowed in a storage position against a wall.

Abstract: A mixer-conditioner for two components to be separately stored and extemporaneously mixed on their first utilization. The system comprises two compartments, each containing one of the components, an obturation element providing a tight seal between said compartments, the obturation element being movable between a closed position and an open position and arranged, when in the closed position, in a communication passage between the compartments, and being integral with a connection element engaged with a rotary actuation member whose operation causes the opening of the communication passage between the compartments by displacement of the obturation element in order to enable mixing of the components.

Abstract: A power tool, especially a handheld sander, is described, possessing a motor-driven drive shaft that can be alternatively coupled either by means of an oscillation drive to an oscillatory tool drive shaft, or by means of a rotary drive to a rotary tool receptacle coaxial with the oscillatory tool drive shaft. Switching is provided by a switching element, in a first switch position of which the drive shaft is driven in an oscillating manner about the lengthwise axis of the oscillatory tool drive shaft, with a small pivot angle and at high frequency, by means of the oscillation drive, which can consist for example of an eccentric element on the tool drive shaft and a pivot element guided slidingly thereon and fastened on the tool drive shaft. In the second switch position of the switching element, however, the working engagement of the oscillation drive is abolished, and the tool receptacle is rotationally driven by the drive shaft by means of a bevel gear linkage.

Abstract: A combined label printer and application device is provided for labeling a plurality of individual product units with customized labels. The individual product units are conveyed through a data determining mechanism, such as a checkweigher or electric eye in order to identify data to be imprinted on the label. The information is conveyed to a microprocessor which converts the data into commands for a label printer. The printer in turn prints either alpha-numeric indicia, bar codes or other desired visual indicia on the label. The movement of the individual product units is coordinated with a corresponding label, and the label is applied to the product unit by means of a combined vacuum and air jet head. The individual labels, in a preferred embodiment, are coated with pressure sensitive adhesive, and are fixed on rolls to releasible backing strip. The individual labels are stripped from the backing strip and held temporarily on a vacuum head until the desired product unit is located below the head.