Patents Assigned to Danfoss A/S
  • Damping arrangement for damping the oscillations of valve controlled by pressure fluid
    Patent number: 4955194
    Abstract: A damping arrangement for damping the oscillations of valves which are controlled by pressure fluid and the control pressure conduits of which contain a throttle. A characteristic is that initial oscillations can be rapidly stabilized independently of the operating temperature of the pressure fluid. This is accomplished by the throttle having a throttle gap of which the height varies oppositely to the temperature of the pressure fluid so as to compensate fully or partially for changes in the hydraulic resistance that are occasioned by the temperature. The throttle gap is mostly traversed by laminar flow and consequently there is a high hydraulic throttling resistance even at low speeds of flow. The throttle is therefore also adapted effectively to damp small oscillations of the valve element so that the initial oscillations are rapidly stabilized.
    Type: Grant
    Filed: October 10, 1989
    Date of Patent: September 11, 1990
    Assignees: Danfoss A/S, Danfoss A/S
    Inventors: Thorkild Christensen, Svend E. Thomsen, Siegfried Zenker
  • Oil supply system for a burner nozzle including means for preventing the nozzle from dripping
    Patent number: 4941505
    Abstract: In order to prevent dripping in an oil supply system for a burner nozzle there is provided a pump stop valve in the supply line that connects the pressure outlet of the pump to the burner nozzle and a nozzle shut-off valve in the supply line between the pump stop valve and the nozzle. A circulating valve is provided in parallel to the pump stop valve to open when the pressure between the pump stop valve and the nozzle shut off valve is higher than the pressure at the pump outlet. As a result if the oil in the supply line adjacent the nozzle expands, oil can return through the circulating valve to the line between the pump stop valve and the pump outlet.
    Type: Grant
    Filed: April 10, 1989
    Date of Patent: July 17, 1990
    Assignee: Danfoss A/S
    Inventors: Poul Kirkelund, Jorn H. Klausen
  • Articulated vehicle with hydraulic steering
    Patent number: 4940106
    Abstract: A double acting hydraulic shock absorber is connected across first and second fluid conduits that are connected to opposite ends of hydraulic steering motors of an articulated vehicle and to a control unit that is controlled by a steering wheel to control the direction of movement of the vehicle. A pump provides pressurized fluid to the control unit. The shock absorber has a response pressure of a predetermined value and includes a piston in a tubular housing intermediate portion. A first shank is joined to the piston to abut against a first closure that closes one end of the housing to limit movement from the piston's datum position and a second shank joined to the piston to abut against a second closure that closes the opposite end of the housing to limit movement from the datum position toward the second closure.
    Type: Grant
    Filed: May 1, 1989
    Date of Patent: July 10, 1990
    Assignee: Danfoss A/S
    Inventors: Harry E. Pedersen, Ole V. Sorensen
  • Connecting rod for an axial piston compressor
    Patent number: 4939952
    Abstract: There is provided a connecting rod for connecting a crank pin of an electric motor to a reciprocated piston. The connecting rod includes a sheet metal shaped member that at each end has a deep drawn cylinder mounting which in turn mounts a bushing that is of a greater axial length than the cylinder mounting. The shaped member has a longitudinal bead providing a depression extending adjacent to one of the mountings and terminate in spaced relationship to the other mounting whereby there is a planar surface extending transversely across the member longitudinally between the bead and the other mounting and adjacent to the widest part of the member to provide a bending line.
    Type: Grant
    Filed: January 9, 1989
    Date of Patent: July 10, 1990
    Assignee: Danfoss A/S
    Inventors: Bendt W. Romer, Kurt G. Jorgensen
  • Apparatus for decalcifing water by producing turbulence
    Patent number: 4940538
    Abstract: An inlet nipple and a housing having a water passage extending therethrough that have first, second and third water bore portions of progressively larger diameters in a downstream direction. A variable throttle point is formed by a fixed member and a movable member acting in conjunction with the bore portions that produce a turbulent flow causing cavitation downstream of the throttle point independently of the quantity of flow. In one embodiment the movable member includes a closure portion seatable against a seat formed at the intersection of the bore portion and an annular portion that in conjunction with a bore portion forms an annular water flow space downstream of the closure portion. In the second embodiment the fixed member has a closure portion converging toward an aperture in the movable member which is in the shape of a cup.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: July 10, 1990
    Assignee: Danfoss A/S
    Inventors: Erik Kyster, Niels-Henrik G. Jakobsen, Jens J. Molbaek, Ole Stenderup, Bjarne Straede
  • Evaporator pressure regulating valve controlled by an auxiliary force for a refrigerator installation
    Patent number: 4934156
    Abstract: In a refrigeration system there is provided a main valve that has its inlet port fluidly connected to an evaporator while its outlet port is fluidly connected to the suction port of a motor-compressor. The closing of the main valve is controlled by an auxiliary valve, the auxiliary valve being connected in an auxiliary line that at one end opens to the gas port of a condenser or to a line between the condenser and the motor compressor. The auxiliary valve is connected in the auxiliary line in series with a fixed throttle and is downstream of the throttle. The closure member of the auxiliary valve opens on an increase in the evaporator pressure. A check valve, for example a two way magnetic valve, is connected between the auxiliary valve and the suction port.
    Type: Grant
    Filed: June 30, 1989
    Date of Patent: June 19, 1990
    Assignee: Danfoss A/S
    Inventor: William J. Barbier
  • Electric laminar resistor and method of making same
    Patent number: 4910492
    Abstract: An electric laminar resistor and the method of making same wherein a thin metal film is applied to a ceramic substrate. Metal film material is removed to form a resistance track and recessed connecting zones at opposite ends of the track. A burnt-in thick layer paste is extended through the connecting zone recesses and solidified to form connecting elements that are adhered to the substrate. A glass frit coating is applied over the resistance track, but not over the connecting elements. The resistance of the resistor may be adjusted by separating a part of the track.
    Type: Grant
    Filed: April 10, 1989
    Date of Patent: March 20, 1990
    Assignee: Danfoss A/S
    Inventors: Kristian Iversen, Per G. Zacho
  • Clutch and brake apparatus operable by compressible fluid, especially pneumatically
    Patent number: 4901830
    Abstract: A housing mounts an input shaft with a clutch flange thereon, an output shaft with a clutch plate thereon, and bearings, sleeves and adjustment nuts for retaining the shafts in selected axially adjusted positions. The clutch plate and flange extend within a clutch chamber of the housing. Friction linings are mounted on the radial outer portion of the flange on opposite sides thereof. The radial outer portions of the plate and flange have depressions into which the linings extend whereby the axial dimension of the chamber is less than the combined axial dimensions of the linings and the plate and flange radially inwardly of and adjacent to the depressions. Switching apparatus provides a pressure differential on axial opposite sides of the plate to eleastically deform the plate between a neutral position, a braking position and a driving position.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: February 20, 1990
    Assignee: Danfoss A/S
    Inventor: Henrik Dolby
  • Thermostatic mixing valve
    Patent number: 4901916
    Abstract: A thermostatic mixing valve has a connection housing and an attachment housing which are joined together at abutting surfaces. The connection housing has hot, cold and mixed water passages which mate with respective hot, cold, and mixed water passages in the attachment housing. The attachment housing further has valve means for controlling the temperature and quantity of the mixed water.
    Type: Grant
    Filed: January 6, 1989
    Date of Patent: February 20, 1990
    Assignee: Danfoss A/S
    Inventor: Rolf I. Avelov
  • Rotary machine with a measuring device for the angle of rotation
    Patent number: 4893007
    Abstract: The invention relates to a device or arrangement for measuring the angle of rotation of the rotor of a rotary machine. Markings are applied circumferentially to a part of the rotor that is enclosed by the housing and a passage is provided in the housing which has an opening adjacent the markings. A sensor arrangement disposed at least partly in the housing passage has one end thereof adjacent the markings in a position for detecting the rotational movement of the markings. The snesor arrangement may have electrical, magnetic or optical capabilities.
    Type: Grant
    Filed: April 29, 1988
    Date of Patent: January 9, 1990
    Assignee: Danfoss A/S
    Inventors: Jorgen C. Stannow, Bruno Wolff, Niels H. Gade, Ib M. Espensen, Knud Blohm
  • Control means for a hydraulic servomotor
    Patent number: 4870892
    Abstract: A control system for a two way acting hydraulic servomotor wherein the servomotor is connected in the diagonal of a bridge circuit that includes four magnetic valves with a pair of the valves being normally open in a non-energized condition being connected to the one end of the servomotor and to the container and a second pair of the valves being normally closed in a deenergized condition being connected to the opposite end of the servomotor and to a pressure source. Circuitry provides pulse trains that are modulatable to control the operation of the magnetic valves and thereby the application of pressurized fluid to the opposite ends of the servomotor.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: October 3, 1989
    Assignee: Danfoss A/S
    Inventors: Flemming Thomsen, Harry S. Nissen, Kjeld Ravn, Carl C. Dixen
  • Compressor spring mounting
    Patent number: 4871300
    Abstract: This invention relates to an insert freely displaceable in a coil spring that at opposite ends abut against spring support formed in a motor compressor unit capsule and a spring support formed by a stator plate. The spring supports project into the opposite ends of the spring to extend toward one another. The opposite ends of the insert are recessed to be of shapes generally corresponding to the adjacent parts of the supports. The insert serves as a transport abutment and permits lateral movement without excessively deforming of the spring.
    Type: Grant
    Filed: July 14, 1988
    Date of Patent: October 3, 1989
    Assignee: Danfoss A/S
    Inventor: Svend E. Outzen
  • Thermostatic mixing valve
    Patent number: 4863097
    Abstract: This invention relates to a thermostatic mixing valve that includes a housing, temperature control valves in the housing that have axially spaced cold and warm water regulating bases and a valve element for cooperating with the above valve bases to reversely vary the flow of the cold water and warm water to the housing outlet port, and cold and warm water quantity setting valves upstream of the temperature regulating valves for controlling the quantity of the cold and warm water flow from the housing cold water and warm water supply ports to the cold and water regulating valves respectively. The quantity setting valves have axially spaced quantity setting valve bases and a common valve member axially movable relative to the quantity setting valve bases for controlling downstream flow from the supply ports, the pressure at the supply ports acting in the same axial direction against the common valve member.
    Type: Grant
    Filed: December 27, 1988
    Date of Patent: September 5, 1989
    Assignee: Danfoss A/S
    Inventor: Rolf I. Avelov
  • Priority valve for hydraulic installations
    Patent number: 4858515
    Abstract: The invention relates to a priority valve for a hydraulic installation having a main circuit and an auxiliary circuit. The priority valve has a slide member which primarily has a controlled throttle for dividing the supply fluid between the main and auxiliary circuits in accordance with the priority demands of the main circuit. The priority valve has a flow path leading to the auxiliary circuit which has throttle elements in series which provide pressure drops in steps to minimize cavitation when there is a rapid flow of fluid in the auxiliary circuit.
    Type: Grant
    Filed: November 18, 1985
    Date of Patent: August 22, 1989
    Assignee: Danfoss A/S
    Inventor: Niels G. Karlberg
  • Electric laminar resistor and method of making same
    Patent number: 4853671
    Abstract: An electric laminar resistor wherein a thin metal film is applied to a ceramic substrate. Metal film material is removed to form a resistance track and recessed connecting zones at opposite ends of the track. A burnt-in thick layer paste extends through the connecting zone recesses and solidified to form connecting elements that are adhered to the substrate. A metal powder and glass frit coating is applied over the resistance track. The resistance of the resistor may be adjusted by separating a part of the track.
    Type: Grant
    Filed: June 27, 1988
    Date of Patent: August 1, 1989
    Assignee: Danfoss A/S
    Inventors: Kristian Iversen, Per G. Zacho
  • Regulating device for the superheat temperature of the evaporator of a refrigeration or heat pump installation
    Patent number: 4845956
    Abstract: The invention relates to a device and method for regulating the superheat temperature of the evaporator of a refrigeration or heat pump system. The existing and desired superheat values are compared at intervals of two and the rate of departure between these two values is utilized for adjusting the desired superheat value.
    Type: Grant
    Filed: April 4, 1988
    Date of Patent: July 11, 1989
    Assignee: Danfoss A/S
    Inventors: Bjarne K. Berntsen, Mads F. Prebensen, Ole Ploug
  • Multi-groove and spline connection between gear shaft of a rotary piston machine with internal axis and method of making such a multigroove spline connection
    Patent number: 4827800
    Abstract: The invention relates to a multi-groove and spline connection between a gear and cardan shaft of a rotary piston machine with an internal axis, wherein external toothing at the head of the cardan shaft engages internal toothing of the gear and an axial abutment co-operates with the end face of the head. The abutment is such that it is only contactable by the teeth of the head of the cardan shaft.
    Type: Grant
    Filed: July 11, 1988
    Date of Patent: May 9, 1989
    Assignee: Danfoss A/S
    Inventors: Poul H. H. Pedersen, Ivar Rasmussen
  • Sealing apparatus with elastic seal ring and plastic slide ring
    Patent number: 4828272
    Abstract: A hydraulic sealing apparatus for sealing an annular gap between two members which are movable relatively to each other and one of which has an annular groove for receiving the sealing apparatus, the groove having a side wall at least on the low pressure side, comprising an elastic ring and a slide ring which consists of a slidable plastics material and has an annular sealing rib at its free circumferential surface.
    Type: Grant
    Filed: February 29, 1988
    Date of Patent: May 9, 1989
    Assignee: Danfoss A/S
    Inventor: Poul H. H. Pedersen
  • AC rectifier circuit with means for limiting the rectified voltage
    Patent number: 4811189
    Abstract: The invention relates to an AC voltage supplied rectifier circuit with a downstream smoothing capacitor. A prior art problem with this type of circuit was that the inductive impedance of the supply voltage caused a practically umdamped oscillation between the inductive supply impedance and the smoothing capacitor during start-up which caused the voltage to rise to about twice the stationary value. A rectifier circuit is provided which substantially prevents the over-oscillation having at least one controllable rectifier which brings the rectifier to a conductive state during the charging period of the smoothing capacitor over such a time that the output direct voltage of the rectifier circuit exceeds the momentary capacitor voltage by no more than a predetermined limited value.
    Type: Grant
    Filed: March 28, 1988
    Date of Patent: March 7, 1989
    Assignee: Danfoss A/S
    Inventors: Nils-Ole Harvest, Jorgen Rasmussen
  • Electric machine with a sheet metal packet carrying a winding and a method of making same
    Patent number: 4808872
    Abstract: An electric machine that includes a stator having a sheet metal packet which has an end plate at each end, and insulating plates abutting against the end plates. The packet has radially inwardly opening winding grooves. Insulating plates are provided at the ends of the packet and have recesses that correspond to the grooves and ribs that form abutment faces against which winding liners provided in the grooves abut. The ribs are shaped such that the windings emerging from the grooves will not cut through the liners when bent sharply. The ends of the groove liners are shaped by thermal stamping to lie against the side faces of the ribs.
    Type: Grant
    Filed: March 28, 1988
    Date of Patent: February 28, 1989
    Assignee: Danfoss A/S
    Inventors: Egon Lund, Poul Petersen