摘要:
Auto-adhesive display film comprising at least one electrically charged, dielectric layer (2). A screen layer (3), which is adapted to form a barrier to the electric field, is fixed to one surface of the dielectric layer (2). This display support does not attract dust particles and is specifically adapted to be printed sheet by sheet.
摘要:
In order to separate, within a fluid (1), certain particles (2) contained therein, this fluid is arranged in a corridor (C) partly defined by two faces which are close together and substantially parallel to each other and to the direction of separation E and an exciting field is simultaneously applied to the entire volume of fluid contained in this corridor, according to a direction having at least one component perpendicular to the direction E, which exciting field varies along the said direction in a curve consisting of a regular sequence of mutually identical asymmetric patterns, the mean of this field, taken at each instant along the direction E, being zero, and means are provided for repetitively varying the effect of the exciting field on the particles. The substantially parallel faces may be electrodes between which a potential difference source is connected for producing an electric field thereby exciting particles in the corridor (C). At least one of the electrodes has a corrugated surface with a sequence of asymmetric grooves transverse to the separation direction.
摘要:
A device is provided for grounding a metal vehicle body or the like, comprising an arrangement for automatically creating at desired times, between the body (1) and the ground (3), ions which, under the effect of the electric field which may exist between the body and the ground, are driven towards the body or towards the ground depending on their polarity and thus equalize the potentials of the body and the ground.
摘要:
The invention relates to an electronic circuit for remote interrogation of a receiver through a two wire line and to detect the response signals emitted by this receiver. The circuit comprises means for comparing with a reference voltage the actual voltage defining said response signals. This reference voltage is a weighted variable voltage obtained by low band-pass filtering, in a resistance-capacity circuit, of said actual voltage.
摘要:
A portable case (2) is provided for emitting, in response to pressure on a push button (1), a control signal (S) coded in accordance with a code recorded in said case. Timing means (8) are provided for automatically neutralizing the code when a predetermined time has elapsed from a predetermined moment, which then makes the case inoperative.
摘要:
.[.The invention relates to a flexible composite sheet designed to constitute an undersheet behaving as an electromechanical transducer in order to detect the apnea of subjects lying on it. This sheet comprises, in addition to a foil sensitive to pressure in the sense of electromechanical transduction (an electret or polarized piezoelectric foil), two film electrodes and two protective foils. Spacing shims are glued to the two foils against which they are juxtaposed. When the sensitive foil is an electret, the shims are directly interposed between the sensitive foil and one of the two electrodes. When the sensitive foil is a polarized piezo-electric foil, the shims are directly interposed between one of the electrodes and the corresponding external protective foil..]. .Iadd.An apnea monitor/alarm consists of an electronic monitor circuit to actuate an alarm responsive to the output of a sheet-like electromechanical transducer. The transducer consists of an electret or polarized piezoelectric foil responsive to pressure to generate corresponding electrical signals, two film electrodes, and two protective foils. Shims are glued to two of the foils for spacing. If an electret sensor foil is used, the shims are directly interposed between the sensitive foil and one of the electrodes. If the sensitive foil is a polarized piezoelectric foil, the shims are directly interposed between one of the electrodes and the corresponding external protective foil. .Iaddend.
摘要:
The invention relates to a circuit breaker for cutting off the two AC supply leads of an electrical receiver from the time of creation of a leakage current F between said receiver and ground through a human body. This circuit breaker comprises a differential transformer generating a faulty voltage V.sub.O, a relay with contacts open when it is not energized, and means (A.sub.1,A.sub.2, . . . A.sub.n ; R.sub.1,R.sub.2 . . . R.sub.n) supplied by the system, adapted to exploit the voltage V.sub.O for the purposes of energizing the relay if the current F is dangerous or at least unpleasant in its intensity and/or its duration, without however being sensitive to disturbances.
摘要:
The device comprises, on the one hand, a cassette containing an electret between two electrodes and, on the other hand, a fixed reader adapted to receive the cassette in a pocket, to identify it, to measure the charge of its electret and to display data relating to this charge. This reader comprises also a head adapted to record the data on an area (or strip) of the cassette and there are provided readers independent of the aforesaid reader adapted to subsequently receive the cassette, to measure the charge of its electret, to read the data and, by difference between the measured value and that read, to display the radiation dose received by the cassette since its recording.
摘要:
The invention relates to devices of the relay type, but using an electrostatic force, rather than a magnetic force, for moving the mobile element. A device according to the invention allows to produce a modification in one or several controlled circuits under the control of a modification or order in an actuating or controlled circuit.The device essentially includes two control electrodes, between which a potential difference may be applied (when desired) using an electrical power source and a control switch, and an electret constituted by an insulating element carrying electrical charges of opposite signs (negative and positive charges), the electret or the algebraic sum of which is different from zero; one of the electrodes is mobile and can occupy at least two positions.The device may be applied to realize electrical, pneumatic, hydraulic or optical switchings.
摘要:
A smoke detector includes a drift chamber and an ionization chamber formed by a first electrode and a second electrode. Electric charges are generated by ionization of the air. The drift chamber separated from the ionization chamber by the second electrode. The smoke particles penetrates from the environment to a detector inside the drift chamber. The electrical potential of first electrode exceeds a critical electric potential value for generating a corona discharge in the vicinity of the first electrode. The second electrode has openings for the electric charges generated in the ionization chamber to move to the drift chamber. The electric potential of the second electrode allows the electric charges in the drift chamber to move from the second electrode to the third electrode. The electric field between the second and third electrodes is at least 100 times weaker than the electric field between the first and second electrodes.