Orbisphere Laboratories Neuchatel Sa

Orbisphere Corporation, Wilmington, Succursale De Collonge-bellerive

Orbisphere Corporation Wilmington

Orbisphere Corporation

Orbishpere Laboratories Neuchatel Sa

Succursale De Collonge-bellerive

Obisphere Corporation Wilmington, Succursale De Collonge-bellerive

Eugen Weber

John M Hale

Harry D Wright

Gerard R Stehle

Jean-Paul Pellaux

Ion Bals

Antoine Gagnebin

Francedillaois Gretillat

A membrane-enclosed sensor (1) of the type having a membrane (11) for exposure to a fluid external phase of analytical interest at an interface between the fluid external phase or sample, and said membrane; the sensor comprises a coiled, e.g. spiraloid, channel (15) at the interface; the channel has an inlet end (16) as well as an outlet end (18) for passing the external phase in contact with the membrane along said coiled channel which, preferably has a length which is at least about 5 times greater than the largest cross dimension of the membrane.

Membrane-enclosed sensor, flow control element and analytic method

An analytic device (1) for reflective luminoscopy comprises within an enclosure (11): a light source (12); a pair of spaced light detectors (141, 142); and a refractor body (16); the refractor body comprises a planar base (161), an entry plane (163) near the light source for light emanating therefrom, and an exit plane (165) near the spaced detectors for light that is being sensed by at least one of the detectors; the entry plane and the exit plane enclose an angle of less then 180.degree. and not less than 90.degree., the enclosure further includes a light-collimating means or lens (13) between the light source and the entry plane; a light-collecting means or lens (15) between the light detectors and said exit plane, and at least one light-reflecting surface (171) near the planar base (161); at least one luminoscopic layer (191) normally comprising a luminoscopic indicator and a thin transparent carrier, is arranged between the planar base and the at least one light-reflecting surface; the device includes both a luminoscopic reference as well as a measuring area for a luminoscopic reaction between a luminoscopic layer and a species of analytic interest.

Luminoscopic analytic device and method

A probe for measuring the concentration of an alcohol, such as ethanol, in a liquid, such as water. The probe according to the invention has a membrane that is permeable for vapors of the alcohol but substantially impermeable for the liquid; a measuring chamber having an open end closed against the liquid by the membrane is provided and has an inlet and an outlet; a pump or other pressure means serves to feed a purge gas, such as air, via the inlet into and out of the measuring chamber; a valve is provided near the inlet for controlled passage of the purge gas through the chamber; a suitably dimensioned detector including a pellistor or a gas-sensitive resistor is arranged in the measuring chamber for quantitative detection of the alcohol and for generating an electrical signal in proportion with the detection.

Probe and method for detecting alcohol

A method of determining a specific thermal conductivity parameter of a target gas having a known general thermal conductivity and being contained at a concentration of interest in a fluid medium (F) and comprising: contacting said fluid medium with an organic polymer membrane (11) provided at an interface between said fluid medium (F) and a sensing volume (12) containing a thermal conductivity sensor (13); the membrane (11) is substantially impermeable for any liquid components of the fluid medium (F) but has a known permeability for the target gas; the sensing volume (12) is periodically purged or flushed with a gas having a general thermal conductivity that differs from the thermal conductivity of the target gas; permeation of the target gas through the membrane (11) into the sensing volume (12) is permitted intermittently; at least one time-dependent parameter of the known general thermal conductivity of the target gas that has permeated into the sensing volume (12) is measured; and a parameter of analytical interest, e.g. a partial pressure of the target gas in the fluid (F), is calculated (14, 15) from the time-dependent value obtained and the predetermined permeability of membrane (11) for the target gas.

Method and apparatus for determining specific thermal conductivity

The concentration of a gas, such as carbon dioxide, in a fluid medium, such as an aqueous beverage, is monitored by pulsatingly measuring a specific parameter of diffusion of the gas through a membrane that is in contact with the fluid medium and is permeable for the gas but impermeable for the fluid; the gas is allowed to diffuse during a period of time into a receiving space of known volume; the amount of gas that diffuses into the receiving space is determined e.g. by measuring IR-absorption, heat conductivity, volume, pressure or the like physical parameters that depend upon the amount of gas in the volume; this yields a specific diffusion parameter or flux. The gas concentration of interest is then calculated from the specific parameter and a previously determined general parameter of diffusion of the gas through the membrane. Pulsating operation, i.e. a repeating sequence of cyclic removal and measuring phases, is characterized by relatively short phases; since, at the same time, the receiving space volume is relatively small while the gas permeability of the membrane is relatively low, reliable results can be obtained in quick response to concentration changes. The method can be applied for monitoring or for controlling the gas concentration by adding sufficient gas to maintain a desired gas concentration in the fluid medium.

Method and apparatus for monitoring gas concentrations

A method of thermal protection of a membrane-enclosed amperometric cell of the type comprising an electrolyte within an electrolyte space containing electrodes and enclosed by a semi-permeable membrane which defines a sensor face; heat exchange within said cell is effected for controlled heat compensation of the electrolyte when the sensor face is exposed to temperatures outside of the operative temperature range of the cell.

Thermal protection method for electroanalytical cell

A method of thermal protection of a membrane-enclosed amperometric cell of the type comprising an electrolyte within an electrolyte space containing electrodes and enclosed by a semi-permeable membrane which defines a sensor face; heat exchange within said cell is effected for controlled heat compensation of the electrolyte when the sensor face is exposed to temperatures outside of the operative temperature range of the cell. A membrane-enclosed amperometric probe having an elongated body provided with a sensor face at one end of the body and with electrical electrode connections extending through the probe body; the body includes at least two elongated fluid-passing conduits which are not in fluid communication with the electrolyte space and which extend in axial direction through the body from a first region near the one body end to a second region near the other body end; the conduits have mutually communicating ends in the first region and separate fluid-feeding ends in the second region so as to permit passing a fluid through the probe body.

Thermal protection method for electroanalytical cell and amperometric

A method of thermal protection of a membrane-enclosed amperometric cell of the type comprising an electrolyte within an electrolyte space containing electrodes and enclosed by a semipermeable membrane which defines a sensor face; heat exchange within said cell is effected for controlled heat compensation of the electrolyte when the sensor face is exposed to temperatures outside of the operative temperature range of the cell. A membrane-enclosed amperometric probe having an elongated body provided with a sensor face at one end of the body and with electrical electrode connections extending through the probe body; the body includes at least two elongated fluid-passing channels formed between a pair of coaxially arranged interfitting tubular members that extend in axial direction through the body from a first region near the one body end to a second region near the other body end; the channels have mutually communicating ends in the first region and separate fluid-feeding ends in the second region so as to permit passing a fluid through the probe body.

Thermal protection for electroanalytical cell and amperometric probe

A device for mounting and securing a membrane made of a substantially flat piece of flexible polymer film on an amperometric cell that has a substantially cylindrical cell end frontally provided with an electrolyte-bearing sensor face by means of a removable annular holding member; according to the invention the holding member is a substantially non-resilient and creep-resistant die ring, preferably made of stainless steel, having a cylindrical inner surface that fits slidingly onto the cylindrical cell end and at least one tapered inner surface portion that extends outwardly from the cylindrical inner surface toward a leading end of the die ring; the leading end of the die ring is moved over the cylindrical cell end whereby the polymer film is deep-drawn between the die ring and the cylindrical cell end and is permanently shaped to form a cup-shaped membrane portion extending over the electrolyte-bearing sensor face and the adjacent portion of the cylindrical cell end; the resulting cup-shaped membrane portion is sealingly held by the die ring on the cylindrical cell end during operation of the amperometric cell. A membrane-enclosed amperometric cell having a cylindrical cell end frontally provided with an electrolyte-bearing sensor face, a semi-permeable membrane formed of a flexible polymer film and extending over the sensor face; a circumferential portion of the membrane is in contact with the cylindrical cell end; a removable annular holding member is arranged around the circumferential portion of the membrane and presses the circumferential portion of the membrane sealingly onto the cell end; according to the invention, the annular holding member is a non-resilient and creep-resistant die ring, preferably made of stainless steel, having a cylindrical inner surface slidingly fitting onto the cylindrical cell end and at least one tapered inner surface portion outwardly extending from the cylindrical inner surface toward a leading end portion of the die ring; the membrane has a permanently formed cup-shaped portion extending over the electrolyte-bearing sensor face and an adjacent portion of the cylindrical cell end; the cup-shaped membrane portion is sealingly held by the die ring on the cylindrical cell end during operation of the cell; the die ring can be removed; e.g. for cell maintenance and re-used for applying and shaping a fresh membrane.

Device for mounting and securing a membrane on an amperometric cell

A keyboard for input of data or control signals into an electronic measuring instrument, computing device or the like including a keyboard panel, a number of pushbutton switch elements arranged under the keyboard panel and having manually controlled ends that extend upwards through openings in the keyboard panel, and sealing means for preventing penetration of water through the openings of the keyboard panel; for such prevention of water penetration, each of the keyboard panel openings around the upwardly extending end of the switch elements is provided with a resiliently elastic hollow capsule that projects upward from the keyboard panel; each capsule is a substantially integral body comprising a substantially hollow cylindrical neck section at the lower capsule end, an adjacent deforming section and a keying area section at the upper capsule end; the deforming section of the capsules forms an elastic shape-restoring bulge whose outer diameter is greater than the outer diameter of the associated neck section; each capsule is pressed at its neck section region radially against the inner surface of the associated substantially circular opening of said keyboard panel by an essentially rigid and substantially hollow cylindrical element so as to effectively seal each keyboard panel opening and to provide for reliable operation of the pushbutton switches.

Keyboard

A method of mounting and securing a membrane of polymer film on an amperometric cell that has a cylindrical cell end provided with an electrolyte-bearing sensor face; the holding member is a substantially non-resilient and creep-resistant die ring, having a cylindrical inner surface that fits onto the cylindrical cell end; at least one tapered inner surface portion extends outwardly toward a leading end of the die ring; the leading end is moved over the cell end whereby the polymer film is deep-drawn between the die ring and the cylindrical cell end and is permanently shaped to form a cup-shaped membrane portion sealingly held by the die ring on the cylindrical cell end during operation of the amperometric cell. An amperometric cell having a cylindrical cell end frontally provided with sensor face, a membrane formed of a flexible polymer film and extending over the sensor face; the membrane is in contact with the cylindrical cell end; a holding member is arranged around the membrane; the holding member is a non-resilient and creep-resistant die ring having a cylindrical inner surface fitting onto the cylindrical cell end and at least one tapered inner surface portion outwardly extending toward a leading end of the die ring; the membrane has a permanently formed cup-shaped portion sealingly held by the die ring on the cylindrical cell end during operation; the die ring can be removed, e.g., for cell maintenance and reused for applying and shaping a fresh membrane.

Membrane mounting method and membrane-enclosed amperometric cell

A sealed adjusting device for mounting in the wall of a sealed instrument housing that includes at least one adjustable element, such as a potentiometer. The adjusting device comprises an elongated sleeve-like mounting hub capable of being sealingly secured in the housing wall, and a normally freely rotatable or freely turnable knob structured as a hollow capsule rotatably inserted onto one end of the mounting hub. The other end of the mounting hub receives or is connected with a portion of the adjustable element. A spring is provided within the mounting hub to hold the knob in its freely turnable or rotatable position. The knob is operatively connected with a clutch-sleeve for temporary engagement with the rotatable operating end of the adjustable element when the knob is pushed against the spring. The knob has a recessed portion fitted with the corresponding outer end portion of the mounting hub and an O-ring is provided between the knob and the mounting hub so as to seal the device and to protect the interior components from contact with water or other contaminants.

Adjusting knob device for electrical instruments and the like

Electroanalytic transducers for electrochemical analysis of chemical substances are disclosed. The transducers are of the type which include electrodes contacting an electrolyte solution. In accordance with the method and apparatus of the invention, means insulating an electrode are held in a mutually pressing engagement over preselected portions of the electrode to insulate that portion from the electrolyte and prevent creep of the electrolyte between the insulating means and the preselected portions. Thus, the surface area of the electrode exposed to the electrolyte is maintained substantially constant during the service life of the transducer. In a preferred embodiment, sensor or working and counter electrodes are coaxially mounted and circumferentially coaxially separated by annular insulating means. Spring means urge the inner coaxially mounted electrode and the annular insulating means together so that only the surface of the cross-sectional end of the inner electrode is exposed to electrolyte. Thus, a working or sensing surface area of the electrode exposed to electrolyte may be maintained substantially constant during service.

Growing community of inventors

Hinwil, Switzerland

Eugen Weber