Patents Assigned to Danfoss
  • Patent number: 5143286
    Abstract: A thermostat top part is mounted to a valve housing for rotation relative thereto and is axially removably secured thereto. The thermostat top part has a retaining ring surrounding and rotatable relative to a hollow cylindrical base foot. A clamping element is mounted by the base foot for radial movement between a position abutting against a clamping face of the valve housing that is tapered axially toward the housing abutment face in a radial inward direction for retaining the top part on the valve housing and a radial outward position permitting the thermostat top part being axially removed from the valve housing. A torsion spring resiliently urges the retainer ring to rotate in a direction for moving the clamping element radially inwardly.
    Type: Grant
    Filed: November 25, 1991
    Date of Patent: September 1, 1992
    Assignee: Danfoss A/S
    Inventors: Henning B. Hansen, Stefan P. Maroti, Bjarne Frederiksen, Knud Lykkegaard
  • Patent number: 5131237
    Abstract: A refrigeration system having compressor controls responsive to the heat load on the system. Each selected evaporator of the system has a thermostatic switch unit which includes an associated temperature sensor in proximity to the evaporator. The thermostatic switch unit has an operating range with ON and OFF threshold values and function to operate an electromagnetic valve which controls the refrigerant admitted to the evaporator. The heat load to which the compressor controls are responsive is derived from the accumulated ON and OFF times of the switch insert.
    Type: Grant
    Filed: February 25, 1991
    Date of Patent: July 21, 1992
    Assignee: Danfoss A/S
    Inventor: Knud V. Valbjorn
  • Patent number: 5127284
    Abstract: The setting apparatus includes a housing having an operating grip mounted thereon for pivotal movement about a first axis between a neutral position and a second position for adjusting a signal changing device. An abutment member is mounted by the housing to pivot about an axis extending perpendicular to the first axis and has a face in abutting relationship to the face of a pressure face member. A rod and a spring are mounted by the operating grip for longitudinal movement and rotary movement relative to the grip to retain the pressure member face in abutting relationship to the abutment member face for selectively adjusting the neutral position of the operating grip upon rotation of the rod and resiliently urging the operating grip to its neutral position when the operating grip is moved out of its various selected adjusted neutral positions.
    Type: Grant
    Filed: October 9, 1990
    Date of Patent: July 7, 1992
    Assignee: Danfoss A/S
    Inventor: Geert Jorgensen
  • Patent number: 5123508
    Abstract: A housing mounts an input shaft with a clutch flange thereon, and an output shaft with an annular friction member thereon to divide the housing clutch chamber into two separate operating chambers. A brake ring has a first friction face facing the friction lining of the friction member while the friction member has a second friction lining facing the clutch flange. The friction member is axially displaceable a limited amounted by a compressible fluid for controlling the movement of the friction linings axially between the linings and into engagement with one of the brake member and the clutch flange. Each of the clutch flange and the brake ring has an annular groove concentric to the coextensive axes of the shafts that opens to the axially adjacent friction lining.
    Type: Grant
    Filed: April 1, 1991
    Date of Patent: June 23, 1992
    Assignee: Danfoss A/S
    Inventor: Svend P. Pedersen
  • Patent number: 5117647
    Abstract: The expansion valve has an inlet connection fluidly connected to a main valve while the main valve is fluidly connected through an outlet connection to the inlet of the evaporator of a refrigeration system. The main valve has a housing that includes a main valve chamber and a valve seat for fluidly connecting the inlet connection to the main valve chamber and a valve member movable between an open position and blocking fluid flow through the valve seat from the inlet connection to the valve chamber. A pressure operated servo arrangement is disposed in the main valve chamber for controlling the movement of the valve element and opens to the pressure outlet of a pilot valve arrangement. The pilot valve arrangement is disposed in a branch path that opens to inlet connection and to the valve chamber downstream of the valve set for controlling the fluid pressure at the pressure outlet.
    Type: Grant
    Filed: April 8, 1991
    Date of Patent: June 2, 1992
    Assignee: Danfoss A/S
    Inventor: Knud V. Valbjorn
  • Patent number: 5115685
    Abstract: The torque meter has a shaft with a reduced diameter intermediate portion with a sleeve that at its axial opposite ends is in fixed axial and rotational relation thereto. The sleeve intermediate portion has circumferentially extending lugs that are joined to the sleeve end portions. The lugs circumferentially opposite their juncture to the sleeve end portion mount an armature. The rotation of the sleeve ends relative to one another axially displaces the armature and changes an electric or magnetic field. At least one coil is in fixed axial and rotational relationship to the sleeve for detecting a change in the field for measuring the torque.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: May 26, 1992
    Assignee: Danfoss A/S
    Inventors: Geert Jorgensen, Torben Jensen, Niels Gade
  • Patent number: 5107584
    Abstract: An electric unit with a plurality of electric circuit elements is manufactured to connect terminals of the electric circuit elements directly using flexible conductors and the entire electric unit is covered by a deformable and contractile tube. Entrance and exit of conductors for connecting the electric unit and an external electric circuit are sealed with waterproof synthetic resin in a watertight manner. At least a portion of the electric circuit unit is capable of being bent. The electric unit can be applied to electric appliances having various shapes and further be easily mounted in a space, for example, such as a corner of the electric appliance even if the available space is curved.
    Type: Grant
    Filed: October 9, 1990
    Date of Patent: April 28, 1992
    Assignee: Danfoss A/S
    Inventor: Hideaki Takeda
  • Patent number: 5097920
    Abstract: Hydraulic steering mechanism is extended through an aperture in an end wall in a housing that has a pressure chamber, the steering mechanism including a slide rotatable with the steering column. An axial bearing is mounted by the end wall for rotatably mounting the steering mechanism while the aperture axially opposite end portion mounts a sealing ring between the housing and the steering mechanism. Axially between the sealing ring and the bearing there is a pressure reduction ring providing an annular gap with the slide for throttling the flow of fluid from the pressure chamber to a fluid collecting chamber that at least in part is defined by the pressure reduction and sealing rings. Fluid can flow from the collecting chamber through a housing outlet. The pressure reduction ring has an enlarged diameter flange for sealingly engaging the end wall and being clamped between the wall and the axial bearing.
    Type: Grant
    Filed: August 30, 1990
    Date of Patent: March 24, 1992
    Assignee: Danfoss A/S
    Inventors: Poul H. Holm-Pedersen, Ivar Rasmussen
  • Patent number: 5093771
    Abstract: An inverter circuit which converts d.c. from a d.c. source to single or multiple phase a.c.. Two semiconductor switching elements for each phase are connected in series between two poles of a d.c. source. A signal generator provides a pulse width modulated signal for operating the switching elements. Blocking elements are provided between the signal generator and the switching elements. A control circuit senses current flow at the a.c. output and selectively enables the blocking elements in accordance with the direction of the current flow to prevent short circuiting between the switching elements.
    Type: Grant
    Filed: January 8, 1990
    Date of Patent: March 3, 1992
    Assignee: Danfoss A/S
    Inventor: Nils-Ole Harvest
  • Patent number: 5085400
    Abstract: A stepped piston is axially displaceable in the stepped piston valve chamber and has a front face facing the front face of the valve seat and an axially opposite surface formed at the juncture of its piston head portion to its reduced diameter shaft portion. The piston has an axial through-bore that opens to fluid connecting bore in the valve housing while the housing has a second fluid connecting bore. The piston is displaceable in the chamber between an open position permitting substantial fluid flow between the connecting bores and a closed position having its front face resting against the valve seat face to permit a leakage flow gap between the faces when pressurized fluid acts against the piston surface and block substantial fluid flow between the first bore and the second bore. A spring in the chamber urges the piston toward its closed position.
    Type: Grant
    Filed: May 28, 1991
    Date of Patent: February 4, 1992
    Assignee: Danfoss A/S
    Inventor: Hans C. Petersen
  • Patent number: 5085769
    Abstract: An oil burner pump that includes a housing having a filter cartridge chamber that has an access opening which is closable by a removable cover. A filter cartridge is removable inserted into the chamber and is securable to the cover to be removed from the chamber when the cover is removed. The cartridge has opposite end portions and filter fabric extended between the opposite end portions, one of the end portions being removably securable to the cover.
    Type: Grant
    Filed: July 2, 1990
    Date of Patent: February 4, 1992
    Assignee: Danfoss A/S
    Inventors: Jorn H. Klausen, Peter Froslev
  • Patent number: 5069075
    Abstract: The flow meter works on the Coriolis principle and has a measuring tube and at least two energy converters. At least one of the energy converters is an oscillation exciter for oscillating the tube to generate a wave traveling along the tube and an oscillation detector. An evaluating circuit uses the speed of travel of waves in the direction of flow of fluid through the tube and in the direction opposite the direction of flow to determine the mass flow of fluid through the tube.
    Type: Grant
    Filed: July 3, 1990
    Date of Patent: December 3, 1991
    Assignee: Danfoss A/S
    Inventors: Henning M. Hansen, Frands W. Voss
  • Patent number: 5062442
    Abstract: The apparatus functions for monitoring small leakages in order to activate an alarm in the event that there has been more than a predetermined volume of small leakage through the water taps or other part of the system and to automatically turn off a main valve if flow continues therethrough more than a predetermined time and will allow the main valve to open if the discharge of fluid is temporary stopped. The system includes a main valve having a valve seat and a shunt circuit that bridges the valve seat. The shunt circuit includes a volume flow meter and a shunt valve for blocking fluid flow through the circuit. The main valve opens only when the volume in the shunt path exceeds a predetermined value. The shunt circuit includes a throttle that when fluid flows therethrough, provides a pressure drop in the shunt circuit which results in the main valve diaphragm opening when the shunt circuit predetermined value is exceeded.
    Type: Grant
    Filed: January 8, 1990
    Date of Patent: November 5, 1991
    Assignee: Danfoss A/S
    Inventors: Theiss Stenstrom, Jens J. Molbaek, Poul E. Hyldig, Bjarne Straede
  • Patent number: 5062305
    Abstract: The measuring tube is for an electromagnetic flow meter and has a tube member made of a non-magnetic material that is provided with opposite through passages that have electrodes extended therethrough. An insulating lining of an enamel priming layer coats the inner surface of the tube member and fills the gaps between the electrodes and the tube member surfaces defining the through passages, the lining also including an covering enamel layer covering the priming layer surface that is within the tube member interior. The end faces of the electrodes that are in the tube member interior have the enamel material cleared therefrom. The priming layer may be formed by filling the tube member with a priming enamel slip, pouring out the slip material, cleaning the electrode end surfaces that are within the tube member interior and then heating to melt the slip material and then cooling. The covering layer may be formed by the same steps.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: November 5, 1991
    Assignee: Danfoss A/S
    Inventors: Henry Hansen, Leif Studsgaard, Erik Laursen
  • Patent number: 5054742
    Abstract: The magnetic valve includes a magnetic coil, at least one valve seat, a valve shank surrounded by a valve plate member and movable upon energizing of the coil to move the surrounding valve plate member away from the valve seat to permit fluid flow therethrough, and a resetting spring for resiliently retaining the valve member in a position for blocking fluid flow through the valve seat when the coil is deenergized. The spring action acting upon the valve plate member moves the valve shank away from the coil upon denergization of the coil. The valve plate member is movable relative to the shank and includes an annular resilient metal plate that has radial inwardly extending teeth and a coating of elastic plastic sprayed on to the plate to leave at least part of the teeth uncoated.
    Type: Grant
    Filed: September 4, 1990
    Date of Patent: October 8, 1991
    Assignee: Danfoss A/A
    Inventor: Holger Nicolaisen
  • Patent number: 5046519
    Abstract: The method and apparatus is directed to monitoring a fluid conduit system for leaks, particularly a leakage flow of less than 25 liters per hour. After closing a main valve that fluidly connects a fluid source to the conduit system, the time is measured for the pressure in the conduit system to drop to a predetermined first value. Upon reaching the first value a shunt valve is opened and the time is measured for the pressure to rise to a second predetermined value. The leakage flow is calculated from the two measured times and the two pressures together with known constants for the control system. In place of providing the shunt valve the main valve may be partially opened. Controls for the valves are provided together with evaluating apparatus for determining the leakage volume.
    Type: Grant
    Filed: October 29, 1990
    Date of Patent: September 10, 1991
    Assignee: Danfoss A/S
    Inventors: Theiss Stenstrom, Jens J. Molbaek, Poul E. Hyldig, Bjarne Straede
  • Patent number: 5045963
    Abstract: The invention relates to a protective circuit for the induction coil of a magnetically inductive type flow meter. If the leads of a flow meter used in an explosive environment are cut there can occur a high voltage and resulting sparking which could cause an explosion. The invention provides a circuit in which a short circuit path is provided for the induction coil if the leads thereof are severed to prevent the development of a high voltage which could cause dangerous sparking.
    Type: Grant
    Filed: March 13, 1989
    Date of Patent: September 3, 1991
    Assignee: Danfoss A/S
    Inventors: Henning M. Hansen, Allan S. Pedersen
  • Patent number: 5038672
    Abstract: The apparatus includes a steeped axially displaceable piston in a stepped cylinder housing, and a rotary shaft is axial fixed relative to the housing and extends into the piston reduced diameter end portion. The piston reduced diameter portion and the housing having a cooperating set of first teeth while the piston and shaft have a cooperating set of second teeth whereby at least one set of the teeth serve to convert axial movement of the piston into rotary motion of the shaft. The shaft is supported in the housing adjacent where it exits from the housing by a first bearing while a second bearing is provide radial adjacent to the juncture of the housing enlarged and reduced diameter portions that supports the interior end portion of the shaft in the piston reduced diameter portion. A third radial bearing is provided between the enlarged diametric portion and the piston enlarged diametric portion in axial remote relationship to the first bearing.
    Type: Grant
    Filed: March 20, 1990
    Date of Patent: August 13, 1991
    Assignee: Danfoss A/S
    Inventor: Hans K. Beuschau
  • Patent number: 5033713
    Abstract: The temperature sensitive apparatus controls fluid flow from one line to others and includes an elongated wire of a shaped memory wire that changes in length with changes in temperature extended into a valve housing for pivotally moving valve mechanism in the valve housing against the action of a spring from a fluid flow blocking position to a position permitting fluid flow upon heating the wire. The wire is connected to the valve mechanism and extends through a tube, both of which extend exterior of the valve housing with the major portion of the length of the wire being exterior thereof. The tube extends into a connecting member housing that is attached to the exterior of the valve housing and contains mechanism surrounding the tube to heat the wire. The tube is substantially thermally insulated from the interior of the valve housing. The heating mechanism may include a generator for an electric alternating field to induce a heating current in the wire, or an A.C.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: July 23, 1991
    Assignee: Danfoss A/S
    Inventors: Niels P. Thorsen, Bjarke Hallenslev
  • Patent number: 5031468
    Abstract: In a flow meter that works on the Coriolis principle there is provided a single tube that is bent to have two measuring loops. Upper and lower tube attachment end portions are respectively connected through resilient tubular portions to the opposite ends of the two loops and may be part of the single tube. The loops are superposed and from the juncture of the loops and through at least parts of the attachment end portions are of a continuous downward gradient such that the fluid column in the flow meter will divide and drain through the attachment end portions. Two blocks have tube holder portions for retaining the loop first ends and the measuring loops opposite ends in vertical spaced relationship and connecting the attachment end portions together. The measuring loops are oscilatable in opposite directions while sensors are provided adjacent to the measuring loops for measuring the relative movement of the loops relative to one another to provide a measurement of the fluid flow through the loops.
    Type: Grant
    Filed: December 20, 1990
    Date of Patent: July 16, 1991
    Assignee: Danfoss A/S
    Inventors: Andreas Back-Pedersen, Ole B. Nielsen, Hans C. Moller