Patents Assigned to City Technology Limited
  • Patent number: 8691066
    Abstract: A current collector wire (1) is over-moulded with a seal (2) made from a thermoplastic elastomer (Santoprene 64) having a (64) Shore A hardness rating. In a three electrode carbon monoxide sensor three current collector wire (1a, 1b, 1c) and seal (2a, 2b, 2c) combinations are inserted into the body (3) through receiving apertures (12a, 12b, 12c) in a side wall of the body, so that the current collectors protrude through connection apertures (12a, 12b and 12c). The outside diameters of the seals and the bores of the apertures are dimensioned to provide an interference fit of the one in the other. The seals are pressed home into receiving apertures in the body (3) to provide compression of the seals against both current collectors and the aperture bores resultant from the interference. Gold-plated phosphor bronze clips (8) are attached which locate on and are retained by barbs on the housing, thereby trapping the current collector wires and providing electrical contact to external circuitry.
    Type: Grant
    Filed: August 12, 2004
    Date of Patent: April 8, 2014
    Assignee: City Technology Limited
    Inventor: Graham Collins
  • Patent number: 8318525
    Abstract: A device for sensing a gas comprises a plastics housing (106, 107) moulded in situ around at least one portion of a conducting lead frame (100), the housing defining an enclosure (113) and being provided with means for enabling gas flow into the enclosure. A gas sensitive element (114) within the enclosure (113) is mounted to the conducting lead frame (100). The conducting lead frame (100) comprises connection leads which are accessible through, and at least partially encapsulated by, the wall of the housing.
    Type: Grant
    Filed: November 25, 2003
    Date of Patent: November 27, 2012
    Assignee: City Technology Limited
    Inventors: David Frank Davies, Ian Paul Andrews, Anthony Richard Cowburn, Stuart Christopher Cutler
  • Patent number: 7575717
    Abstract: Diagnostic testing apparatus for evaluating entrainable substances (e.g. for determining allergen activity in house dust), comprising a housing for collection and testing of entrainable substances, the housing having: an inlet; an outlet; a filter disposed between the inlet and the outlet which is configured to capture substances entrained in air flowing from the inlet to the outlet; a reservoir for storing fluid for use in evaluating substances captured on the filter; and means for releasing stored fluid from the reservoir onto the filter.
    Type: Grant
    Filed: August 16, 2002
    Date of Patent: August 18, 2009
    Assignee: City Technology Limited
    Inventors: Anthony Cooke, Ramin Pirzad
  • Patent number: 7541587
    Abstract: A gas sensor comprises a cavity for containing a gas, means for generating radiation which is transmitted through the cavity and includes one or more wavelengths which is absorbed in use by a gas to be detected; and a detector for detecting radiation which has passed through the cavity. The walls of the cavity are sufficiently reflective to the radiation that the cavity is substantially uniformally illuminated with the radiation.
    Type: Grant
    Filed: December 1, 2004
    Date of Patent: June 2, 2009
    Assignee: City Technology Limited
    Inventors: Stuart Christopher Cutler, Alexander Vass
  • Patent number: 7534333
    Abstract: An electrochemical gas sensor which comprises an electrode assembly, including a catalytic sensing electrode and a counter electrode, mounted inside a housing provided with at least one gas entrance, a reservoir for containing electrolyte in use, a compressible wick for supplying the electrode assembly with electrolyte and a wick compression component. A first end of the wick extends into the reservoir and a second end of the wick contacts the electrode assembly. The wick compression component compresses the wick in a direction substantially radial to an axis joining its first and second ends.
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: May 19, 2009
    Assignee: City Technology Limited
    Inventors: Peyman Khalafpour, Stuart Christopher Cutler
  • Publication number: 20080226505
    Abstract: A gas sensor assembly comprising a gas-sensitive element, and a first pulse modulation circuit comprising a first switching device is disclosed. The gas-sensitive element and the first switching device are arranged in series with a power supply. The first pulse modulation circuit further comprises a first control module adapted to control the first switching device in accordance with a monitored parameter of the gas-sensitive element, the parameter varying with the temperature of the element, thereby controlling the power consumed from the power supply by the gas-sensitive element.
    Type: Application
    Filed: April 18, 2006
    Publication date: September 18, 2008
    Applicant: CITY TECHNOLOGY LIMITED
    Inventors: Martin John Willettt, David Frank Davies, Ali Hosseinmardi, Laurence Joyce
  • Patent number: 7282168
    Abstract: A gas sensor assembly comprises a housing (65) including a bore (61). A pin (50) extends through the bore (61) and an O-ring (100) is located in the bore. The O-ring (100) contacts the pin (50) and parts of the bore (61) so as to be restrained against movement in both lateral and axial directions. Two- and three-shot molding processes are described for fabricating the assembly.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: October 16, 2007
    Assignee: City Technology Limited
    Inventors: Anthony Charles Downer, John Chapples, Andrew Peter Millar
  • Patent number: 7279080
    Abstract: This invention provides an assembly comprising a sensing electrode and a counter electrode in contact with a membrane body formed from a solid polymer electrolyte system comprising a fluorinated polymer matrix and a charge carrying component which is dispersed in the matrix the electrodes and membrane being housed in a housing having a gas diffusion barrier through which gas may flow. The charge carrying components are fluorinated organic proton conductors (such as heptadecafluorooctane sulphonic acid, bis-trifluoromethane sulphonamide, N-(2,6-diethylphenyl)-1,1,1-trifluoromethane sulphonamide, N-benzyltrifluoromethane sulphonamide and N, N-1,2-cyclohexanediylbis (1,1,1-trifluoromethane sulphonamide)). The polymer matrix is a homopolymer or copolymer of vinylidene fluoride preferably with fluorinated comonomers. The solid polymer electrolyte system preferably contains plasticising additive(s) and is cast as a coating onto one or more electrodes eg.
    Type: Grant
    Filed: July 27, 2001
    Date of Patent: October 9, 2007
    Assignee: City Technology Limited
    Inventors: John Chapples, Martin Geoffrey Jones
  • Patent number: 7236095
    Abstract: A method of detecting a predetermined alarm condition in a combustion emission gas. The method comprises exposing to the gas a semiconductor gas sensor having a p-type mixed metal oxide semiconducting material of the first, second and/or third order transition metal series, the semiconducting material being responsive both to a change in concentration of a reducing gas in the surrounding atmosphere and to a change in concentration of oxygen in the surrounding atmosphere to exhibit a change in its electrical resistance. The resistance is monitored and an alarm signal is output if the resistance exceeds a predetermined value corresponding to the alarm condition.
    Type: Grant
    Filed: October 8, 2003
    Date of Patent: June 26, 2007
    Assignee: City Technology Limited
    Inventors: Peter John Smith, Keith Francis Edwin Pratt
  • Patent number: 7195922
    Abstract: A method of determining allergen activity in dust comprises: providing a dust sample; extracting from the dust sample at least one breakdown component or proteins or peptides; reacting the extracted at least one breakdown component with a colorimetric amine detection reagent such as TNBSA; and quantitatively measuring the intensity of any resulting coloration. The allergen activity may be gauged by the intensity of coloration.
    Type: Grant
    Filed: June 9, 2000
    Date of Patent: March 27, 2007
    Assignee: City Technology Limited
    Inventor: Ramin Pirzad
  • Patent number: 7010957
    Abstract: Semiconductor gas-sensitive materials of the formula Cr2-xTixO3 where 0.05>x?0.0001, and gas sensors formed therefrom.
    Type: Grant
    Filed: May 9, 2001
    Date of Patent: March 14, 2006
    Assignee: City Technology Limited
    Inventors: David Edward Williams, Keith Francis Edwin Pratt, Peter John Smith, Dirk Niemeyer
  • Patent number: 6993955
    Abstract: Semiconductor gas sensors with improved selectivity to target gases are provided by having a semiconductor gas-sensing layer and a layer thereon of microporous ceramic oxide having catalytic activity.
    Type: Grant
    Filed: November 23, 2000
    Date of Patent: February 7, 2006
    Assignee: City Technology Limited
    Inventors: Charles Edmund King, Peter John Smith
  • Patent number: 6395230
    Abstract: A method of manufacturing a pellistor comprises providing a porous catalyst layer (11) on a heater by electrodepositing material from a mixture containing the catalyst and a structure-directing agent in an amount sufficient to form an homogenous lyotropic liquid crystalline phase in the mixture.
    Type: Grant
    Filed: March 26, 2001
    Date of Patent: May 28, 2002
    Assignee: City Technology Limited
    Inventors: Samuel Guerin, Philip Nigel Bartlett
  • Patent number: 5761952
    Abstract: An electrochemical gas sensor having a housing in which components of the sensor are mounted. A number of electrical connectors are secured to the housing and coupled to respective sensor components enabling the sensor to be connected to a sensor monitoring system for monitoring an electrical output from the sensor and for determining gas concentration. The housing includes one or more indicating formations whose position on the housing causes an appropriate calibration parameter to be selected.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: June 9, 1998
    Assignee: City Technology Limited
    Inventors: Jonathan Howard Gilby, John Robert Finbow
  • Patent number: 5746899
    Abstract: An electrochemical gas sensor comprises sensing and counter electrodes mounted on the same side of a planar support. An electrolyte is in contact with the sensing and counter electrodes. A capillary controls the access of gas to the sensing electrode. A barrier layer extends over the sensing and counter electrodes, the barrier layer being positioned relative to the capillary and the support being non-electrically conductive and being sufficiently porous such that gas from the capillary is guided transversely and laterally through the support first to reach the sensing electrode and then to reach the counter electrode.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: May 5, 1998
    Assignee: City Technology Limited
    Inventors: John Robert Finbow, Malcolm Robert Bulpitt
  • Patent number: 5668302
    Abstract: An electrochemical gas sensor assembly comprises an electrochemical gas sensor (1) including sensing (39) and counter (32) electrodes, an intervening body of electrolyte contacting the electrodes, and means (5) for controlling the diffusion of gas to the sensing electrode. A test gas generator (7) is connected to the sensor so as to supply a test gas directly to the sensing electrode (39) by-passing the gas diffusion control means (5).
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: September 16, 1997
    Assignees: City Technology Limited, Steven Allan Wylie Dejaray
    Inventors: John Robert Finbow, Malcolm Robert Bulpitt, Steven Allan Wylie Dejaray
  • Patent number: 5632875
    Abstract: An electrochemical gas sensor assembly comprises an electrochemical gas sensor; an electrolyte reservoir (3); and at least one capillary (9) defined by substantially rigid, non-porous walls for conveying electrolyte between the reservoir and the gas sensor.
    Type: Grant
    Filed: June 26, 1996
    Date of Patent: May 27, 1997
    Assignee: City Technology Limited
    Inventors: John Chapples, Peter J. Sewell
  • Patent number: 5601693
    Abstract: A device for sensing a gas comprises a pair of gas sensitive elements (25,26) surface mounted via conductors to a track carrying substrate (23).
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: February 11, 1997
    Assignee: City Technology Limited
    Inventor: David F. Davies
  • Patent number: D494879
    Type: Grant
    Filed: June 23, 2003
    Date of Patent: August 24, 2004
    Assignee: City Technology Limited
    Inventor: Ian Paul Andrews
  • Patent number: D500256
    Type: Grant
    Filed: June 23, 2003
    Date of Patent: December 28, 2004
    Assignee: City Technology Limited
    Inventor: Stuart Christopher Cutler