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公开(公告)号：GB2018506A
公开(公告)日：1979-10-17
申请号：GB7905833
申请日：1979-02-19
Applicant: CHLORIDE GROUP LTD
Abstract: An ionisation chamber, particularly for use as a smoke detector, comprises a negatively charged electrode 4 and a positively charged filament 1 heated to about 500 DEG C. The heated filament 1 causes the surrounding air to ionise and the difference in charge establishes an ionisation current. The presence of smoke particles in the ionised air causes a reduction in the ionisation current, which is detected and used to indicate the smoke level. As shown, the electrodes 1,4 may be disposed in a perforate cage 2 which is held at a positive potential. Alternatively, Fig. 2 (not shown), the negative electrode may itself be constituted by the perforated cage which surrounds the heater filament.
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公开(公告)号：DE1290740B
公开(公告)日：1969-03-13
申请号：DES0058502
申请日：1958-06-06
Applicant: SIEMENS AG
Inventor： PECHE , GERHARD DR-ING , SCHMALENBERG , WERNER DR-ING
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公开(公告)号：GB1079360A
公开(公告)日：1967-08-16
申请号：GB3813465
申请日：1965-09-07
Applicant: GEN ELECTRIC
Abstract: 1,079,360. Electrophysical measurement. GENERAL ELECTRIC CO. Sept. 7, 1965 [Oct. 23, 1964], No. 38134/65. Heading G1N. In a leak detector of the type in which the atmosphere outside the enclosed vessel is sampled for the presence of halogen tracer gas by drawing the air through an ionisation detector 10, the voltage drop across resistor 14 due to ion current is added to a bias voltage tapped off a potential divider 17 so as to cause conduction of a cold cathode thyratron 24 which in turn energizes a neon indicator lamp (not shown) from an A. C. source 28. The firing point of the thyratron 24 is stabilized by illuminating it with a neon lamp 32. A capacitor 21 between control electrode and cathode of the thyratron causes the circuit to act as a relaxation oscillator, the frequency of which is proportional to the amount of tracer gas present. An additional capacitor 36 is also provided to change the time constant of the oscillator to extend the range of indication.
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公开(公告)号：NL6512962A
公开(公告)日：1966-04-25
申请号：NL6512962
申请日：1965-10-06
Abstract: 1,079,360. Electrophysical measurement. GENERAL ELECTRIC CO. Sept. 7, 1965 [Oct. 23, 1964], No. 38134/65. Heading G1N. In a leak detector of the type in which the atmosphere outside the enclosed vessel is sampled for the presence of halogen tracer gas by drawing the air through an ionisation detector 10, the voltage drop across resistor 14 due to ion current is added to a bias voltage tapped off a potential divider 17 so as to cause conduction of a cold cathode thyratron 24 which in turn energizes a neon indicator lamp (not shown) from an A. C. source 28. The firing point of the thyratron 24 is stabilized by illuminating it with a neon lamp 32. A capacitor 21 between control electrode and cathode of the thyratron causes the circuit to act as a relaxation oscillator, the frequency of which is proportional to the amount of tracer gas present. An additional capacitor 36 is also provided to change the time constant of the oscillator to extend the range of indication.
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Patent Agency Ranking
公开(公告)号：GB982162A
公开(公告)日：1965-02-03
申请号：GB4911762
申请日：1962-12-31
Applicant: GEN ELECTRIC
Abstract: 982,162. Bellows. GENERAL ELECTRIC CO. Dec. 31, 1962 [Jan. 2, 1962], No. 49117/62. Heading FIN. [Also in Division G1 In an ionisation type vapour leak detector samples of the atmosphere in the vicinity of a closed container being tested are drawn by a vacuum pump 3 through a conduit 2, which is narrow relative to the cross-section of the region between the electrodes 62, 63, and pumped through a further relatively thin conduit 11 and a diffuser 12 to the ionisation chamber. The pump 3 is of the diaphragm type in which parts 23, 39, Fig. 1a, are given a relative vibratory motion by an a.c. fed actuating coil 30, the parts being mounted on a U- shaped arrangement comprising members 22, 24 and a resilient connecting link 25. Air is taken into a central chamber 49, Fig. 2, from the conduit 2 through channels 10, 48 and holes 53 Fig. 3 in diaphragm 52, when the parts 23, 39, move apart and is forced out through conduit 11 when they return. Screws 35, 38 provide adjustment for the pump stroke and frequency. The diffuser 12 is formed integral with the electrical socket 56, 57 for the ionisation chamber 14, and the heated cathode 62 of the chamber is U-shaped and suspended from a frame 61. Ions are attracted to a wire wound anode 63 by a battery 18 and a current meter in the supply indicates the presence of a leak. The test region need not be gas tight. Specification 950,188 is referred to.
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公开(公告)号：NL6406255A
公开(公告)日：1964-12-07
申请号：NL6406255
申请日：1964-06-03
Abstract: 1,018,337. Measuring fluid flow. COMMISSARIAT A L'ENERGIE ATOMIQUE. June 1, 1964 [June 4, 1963], No. 22509/64. Heading G1R. In an apparatus for measuring gas flows at pressures below atmosphere, such as pressures less than about 10 -3 mm. Hg, the gas is drawn through an adjustable orifice 4, such as an inis diaphragm Figs. 2, 3 (not shown), into a chamber 2 by a pump 5 and the pressure on each side of the orifice is measured by a differential pressure measuring instrument 7 and the pressure in chamber 1 is measured by a gauge 8. The pressure difference on each side of orifice 4 is measured for different openings and the value of such pressure differences are then calculated for infinite and unity conductance, and the actual flow rate is deduced from the difference between these two values. The pressure difference for infinite conductance or free passage of gas corresponds to the constant error of the apparatus and the pressure differences for unity conductance corresponds to the value of the flow measured with an ideal apparatus. The pump 5 may be a diffuser pump conbined with a primary pump. The instrument 7 may be two hot cathode ionisation gauges disposed on each side of the orifice 4; the ionic currents of the two gauges being arranged to break one another, at tube 9 from the discharge 10 of the pump 5 passes some gas to a reservoir 13 to be returned to the chamber 2 subsequently or direct to chamber 2 to maintain the pressure in the chamber 1 at the desired pressure.
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公开(公告)号：GB895604A
公开(公告)日：1962-05-02
申请号：GB4185658
申请日：1958-12-29
Applicant: ICI LTD
Inventor： WILLIS VINCENT
Abstract: 895,604. Determining qualities of materials. IMPERIAL CHEMICAL INDUSTRIES Ltd. Dec. 18, 1959 [Dec. 29, 1958], No. 41856/58. Class 37. A gas or vapour discharge tube is associated with means for detecting and measuring the variation of voltage across the tube and is operated under constant current conditions. Constant. current conditions are achieved by putting the gas discharge tube in the anode circuit of a pentode. As shown, two tubes D1, D2 operating at a pressure of 4 mm. Hg, are placed in the anode circuits of pentodes V1, V2. One tube D1 has carrier gas only and the other tube D2 carrier gas plus the sample of gas or vapour to be detected and a recording potentiometer RP measures the difference in voltage of the two tubes. The voltage difference bears a linear relationship to the gas concentration. The tubes are operated on a part of their characteristic where the burning voltage is constant with variation of discharge current. The device is used as a gas detector in gas chromatography. Specification 895,602 is referred to.
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公开(公告)号：DE1102442B
公开(公告)日：1961-03-16
申请号：DESC018144
申请日：1955-06-14
Applicant: BERTHOLD SCHUMACHER DIPL PHYS
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