Patents Assigned to Danfoss A/S
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Patent number: 6457372Abstract: A flowmeter and a method of determining the mass flow rate. The flowmeter has a first measuring tube and a second measuring tube which are arranged in a common housing and are connected to one another mechanically. Also provided are an excitation device for exciting the measuring tubes to oscillation, and a detector device for detecting oscillation parameters which is connected to an evaluating device, which determines a mass flow rate signal for each measuring tube from output signals from the detector device. The object is to improve the measuring accuracy in cases in which identical conditions do not prevail in the measuring tubes. For that purpose, an amplitude detecting device is provided which detects the amplitude of the oscillation of each measuring tube, and a correcting device is connected to the evaluating device, which correcting device has a flow input and an amplitude input for each measuring tube.Type: GrantFiled: December 12, 2000Date of Patent: October 1, 2002Assignee: Danfoss A/SInventors: Mogens Bech Laursen, Henning Max Hansen
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Patent number: 6459348Abstract: An electromagnetic actuator, especially for the closure member of a valve, contains a solenoid unit, which has a cylindrical cavity closed at one end and open at the other end. An axially introduced guide tube for a magnetically movable armature is arrestable in the cavity by means of a securing device engageable in a first recess under spring force. To simplify connection of the actuator with and separation of the actuator from the component to be adjusted, provision is made for the securing device to lie completely within the solenoid unit and to snap automatically into the first recess when the guide tube is moved into a desired position in the cavity of the solenoid unit.Type: GrantFiled: November 13, 2001Date of Patent: October 1, 2002Assignee: Danfoss A/SInventor: Michael Birkelund
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Patent number: 6454179Abstract: A heating system has several heating devices with valves, controlled in dependence of the temperature, in different rooms, with the heating devices being supplied by a supply device with an adjusting member which acts upon a supply temperature. A control device activates the adjusting member. A heat requirement in the rooms is detected and the supply temperature is adapted accordingly. To keep the energy consumption low, a counter detects the number of rooms in which a heat requirement exists. The supply temperature is increased by a value which corresponds to a product of the number of rooms and a predetermined first temperature difference when the number of rooms is higher than zero. When the number of rooms is equal to zero, the supply temperature is decreased by a predetermined second temperature difference.Type: GrantFiled: November 16, 2001Date of Patent: September 24, 2002Assignee: Danfoss A/SInventors: Christian Neve, Jørgen Seerup, Eva Kühne
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Patent number: 6427923Abstract: A heating system having, in at least one heatable room, at least one first heating device and a second heating device, with the second heating device being of a kind which differs from that of the first heating device, and with both heating devices being controlled. To improve the comfort feeling of a consumer, the two heating devices and their control circuits are coupled with each other, and a change of a parameter in one control circuit causes a corresponding change of a parameter in the other control circuit.Type: GrantFiled: November 16, 2001Date of Patent: August 6, 2002Assignee: Danfoss A/SInventors: Christian Neve, Jørgen Seerup, Eva Kühne
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Patent number: 6405581Abstract: Apparatus for measuring the contents of foreign matters in a fluid, in particular a buoyant apparatus, which has a housing (1) of thermoplastic synthetic material and a hole (4) in the first wall section (2) and a through-hole (5) in a second wall section (3). A sensor (9), arranged in the housing (1) and determined to measure the content of the foreign matter, protrudes into the hole (4). The outer side (10) of the sensor (9) tightly closes the hole (4) with the outer surface of the first wall section (2) and is permeable to the foreign matters that are be measured. Two parts (24,25) of the housing (1) are joined tightly in an area of edge sections (26,27).Type: GrantFiled: April 18, 2000Date of Patent: June 18, 2002Assignee: Danfoss A/SInventor: Ulrik Bruhn
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Patent number: 6405634Abstract: A hydraulic axial piston machine (1) includes a cylinder drum (3) having at least one cylinder (4) in which a piston (5) is arranged to be reciprocating, an inclined swash plate (8), on which the piston (5) is supported via a slide shoe (7), a pressure plate (9) maintaining the bearing of the slide shoe (7) on the swash plate (8), and a spring arrangement (10) by means of which the pressure plate (9) is pressed against the swash plate (8) via the cylinder drum (3). In the past, the pressure plate has been supported on the cylinder drum (3) via a ball joint, with the spring arrangement and a driving shaft for the cylinder drum penetrating the cylinder drum. The ball joint is expensive and exposed to wear. According to the invention, the spring arrangement (10) bears immediately on the pressure plate (9). Thus, a ball joint and the wear of it will be avoided.Type: GrantFiled: October 27, 2000Date of Patent: June 18, 2002Assignee: Danfoss A/SInventor: Ove Thorbøl Hansen
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Patent number: 6397906Abstract: A system for dispensing batches of fluid comprising a flowmeter (5), a pump or valve (6) for starting and stopping the flow and a controller (9) for controlling the pump or the valve. In order to reach a target batch size, the settling time at start of the flowmeter is compensated for as well as for the time it takes to stop the flow by generating a stop signal before the target batch size is reached. Further, to compensate for variations in the actual flow caused by variations in the feed pressure and the like, the compensation is made a function of the actually measured flow. A controller or a batch flow meter for use in dispensing batches is equipped with an interface for setting a compensating time constant and a correction unit for compensation of changes in the flow. The correction unit can consist of a differentiator an a summation circuit. Using digital techniques, the correction unit can be made as a lead filter.Type: GrantFiled: February 9, 2001Date of Patent: June 4, 2002Assignee: Danfoss A/SInventor: Henning Max Hansen
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Patent number: 6363770Abstract: Apparatus for measuring the contents of foreign matters in a flowing liquid, in particular a buoyant apparatus, which has a housing (1) of which at least one wall section (2) is intended to be brought into contact with the liquid, and has a preferably spherical arched outer side and in a hole (4) a sensor (9) for the foreign matter. The sensor (9) has on its outer side in the area of the hole (4) a diaphragm (10) which is permeable to the foreign matters that are to be measured and which is arched and flush with the outer side of the wall section (2). In order to increase the flow velocity in the area of the diaphragm so that no contaminations remain adhered to the outer side of the diaphragm (10) thus influencing its permeability and thereby the measuring ability of the apparatus, the arched outer side of the wall section (2) is equipped with guiding surfaces (11) for the liquid, which project from it and extend transversely to the hole.Type: GrantFiled: April 18, 2000Date of Patent: April 2, 2002Assignee: Danfoss A/SInventor: Ulrik Bruhn
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Patent number: 6354510Abstract: A thermal expansion valve body for a thermal expansion valve. In order to provide universality so that the thermal expansion valve can ultimately be formed with an inlet and outlet either being aligned or at an angle to one another, the thermal expansion valve body includes an inlet protrusion for the inlet an outlet protrusion for the outlet, and a bypass aperture protrusion for a bypass aperture. The outlet protrusion and the bypass protrusion are substantially identical such that the outlet can be formed in one the outlet and bypass protrusions, and the bypass aperture can be formed in the other of the outlet and bypass protrusions.Type: GrantFiled: January 12, 2001Date of Patent: March 12, 2002Assignee: Danfoss A/SInventor: Hans Kurt Petersen
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Patent number: 6354805Abstract: In a known method for regulating a delivery variable of a pump, which is driven by an electric motor operated with alternating current of variable frequency, especially via a converter, the input power of the motor is measured as the actual value for the delivery variable and is regulated by comparison with a desired value. To avoid the influence of the temperature of the motor on the delivery variable at constant input power, according to the invention upon a change in the temperature in the motor a corresponding compensating variable is taken into account in the control for the purposes of correcting the input power. As an alternative, associated values of the input power and the speed of the motor at a predetermined desired pressure value are determined empirically and stored as a table, and during operation a value of the input power belonging to a measured or approximately calculated speed of the motor is retrieved from the table as the desired value for regulating the input power.Type: GrantFiled: July 6, 2000Date of Patent: March 12, 2002Assignee: Danfoss A/SInventor: Eik Sefeldt Møller
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Patent number: 6354508Abstract: The invention concerns an electronic temperature controller, particularly for refrigeration appliances, with mains connections (3, 4) and an electronic circuit (1) having a power supply (7), a control unit and measuring and setting elements (9, 10, 11). The mains connections (3, 4) are connected with the power supply (7) via protective impedances (5, 6) consisting of at least two single impedances connected in series, and the electronic circuit is dimensioned for an operating current of maximum 0.35 mA (peak value) when connected to an AC mains and maximum 1 mA when connected to a DC mains. These values are doubled, when the electronic circuit has an earthing connection. This gives safety for the operator through shock-proof protection, which can be achieved at low cost and with small dimensions.Type: GrantFiled: April 17, 2000Date of Patent: March 12, 2002Assignee: Danfoss A/SInventors: Hans Erik Fogh, Axel Schønwandt
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Patent number: 6351359Abstract: A conventional circuit for blocking a semiconductor switching device (7) on overcurrent, the semiconductor switching device (7) having at least one continuously driven semiconductor switch (9), comprises a diver circuit (11), which has a driver stage (12) for each semiconductor switch (9), a control pulse generator (10) for producing control pulses (P1 to P6), which are fed in operation to a control input of the semiconductor switching device (7) via the driver circuit (11), and a monitoring device (34), which measures the current (I) flowing through the semiconductor switching device (7) and, when an overcurrent occurs, generates a fault signal (E), which initiates blocking of the semiconductor switching device (7). When the semiconductor switching device is being blocked, a high overvoltage can occur therein, possibly leading to destruction of the semiconductor switching device.Type: GrantFiled: August 20, 1999Date of Patent: February 26, 2002Assignee: Danfoss A/SInventor: Jens Ulrik Jæger
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Patent number: 6346186Abstract: A method for electrochemical phosphating of metal surfaces, particularly stainless steel, in connection with cold forming of metal workpieces, which method provides the cold formed workpiece with a lubricant after phosphating, involves an electrochemical phosphating through a cathodic process applying an aqueous phosphating solution containing 0.5 to 100 g Ca2+/l 0.5 to 100 g Zn2+/l 5 to 100 g PO43−/l 0 to 100 g NO3−/l 0 to 100 g ClO3−/l and 0 to 50 g F− or Cl−/l by which the temperature of the solution is between 0 and 95° C., the pH-value of the solution is between 0.5 and 5, and the current density is between 0.1 and 250 mA/cm2. This gives a good lubrication effect, a good adhesion to the metal surface, particularly stainless steel, and a more expedient texture than ordinary phosphating.Type: GrantFiled: August 7, 2000Date of Patent: February 12, 2002Assignee: Danfoss A/SInventors: Niels Janniksen Bjerrum, Erik Christensen, Thomas Steenberg
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Patent number: 6314787Abstract: A forming tool for extrusion has a die (5), which has a forming cavity (6) having at least one critical reference value. The die (5) is surrounded by a biasing ring (8), which bears against it with radial pre-stress. The die (5) and the biasing ring (8) have tampered contact surfaces (11) and are displaceable relative to one another. The biasing ring (8) is surrounded by a reinforcement (9), which bears against it with radial pre-stress. The biasing ring (8) and the reinforcement (9) are mounted in a fixed position on a carrier (housing 1). The die (5) is displaceable relative to the carrier and capable of being locked, by locking means (15, 19) on the carrier, in positions that can be selected. By that means it is possible subsequently to carry out a fine adjustment of the critical reference value over a wide correction range.Type: GrantFiled: July 27, 2000Date of Patent: November 13, 2001Assignee: Danfoss A/SInventor: Jens Grønbæk
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Patent number: 6293513Abstract: A servo-controlled magnetic valve has a main valve (13) and a servo valve (14). The servo valve opens when, after an empty stroke, a solenoid plunger (7) entrains a slide member (23) that carries the servo closure member (20) and, as a result, pressure is released to the low pressure side (17) from a pressure chamber (25) on the side of the servo piston (24) that is remote from the main valve seat (15). The servo piston (24) is an annular piston that surrounds an insert (19) that carries the main valve closure member (18) and the servo valve seat (20) and which, during the operating stroke, entrains the slide member (23) by means of first stops (26) and the insert (19) by means of second stops (28). In that manner, it is possible to obtain sufficient opening of the main valve (13) and a small overall height of the magnetic valve while retaining an initial empty stroke of the solenoid plunger (7).Type: GrantFiled: June 14, 2000Date of Patent: September 25, 2001Assignee: Danfoss A/SInventor: Michael Birkelund
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Patent number: 6264567Abstract: The invention concerns a machine arrangement with a first machine having a first rotation connection, a second machine having a second rotation connection, and a shaft for transmission of a torque, the shaft being unrotatably connected with both rotation connections. In this connection it is desired to minimize the effects of alignment errors on mounting the two motors. For this purpose the shaft (5) has, at least in one end, an external toothing (6) engaging with an internal toothing (8, 9) of the machine at this end, said external toothing permitting a swivel movement of the shaft (5), the teeth (10) of said external toothing (6) having concavely extending tooth flanks (11, 12), whose axial ends (15, 16) are less curved than their area of the axial centre.Type: GrantFiled: November 5, 1999Date of Patent: July 24, 2001Assignee: Danfoss A/SInventors: Finn Lyhne, Tom Tychsen, Hans Christian Petersen, Claus Johansen
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Patent number: 6259617Abstract: Electric bus arrangement (1) for DC-supply of power components, particularly for an inverter, having a first and a second plate (2, 3), arranged in parallel with each other, separated by an isolating layer (4), by which the first plate (2) connects first connections of power components (13) of a first group with first connections (23) of power components (14) of a second group, and the second plate (3) connects second connections of the power components (13) of the first group with second connections of the power components (14) of the second group. In such a bus arrangement an increase of the switching frequency is desired, however without the risk of damaging components due to overvoltage.Type: GrantFiled: March 21, 2000Date of Patent: July 10, 2001Assignee: Danfoss A/SInventor: Jian Mu Wu
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Patent number: 6241379Abstract: A micromixer having a mixing chamber for mixing two fluids. The mixing chamber has a first inlet arrangement for the supply of a first fluid and a second inlet arrangement for the supply of a second fluid. The mixing chamber includes a wall along which the first fluid flows, and the second inlet arrangement has at least one opening in the wall. A projection is located on the wall adjacent to the opening and extending into the mixing chamber so that the first fluid flows around the projection and builds a boundary layer with the second fluid. Mixing takes place by diffusion through the boundary layer.Type: GrantFiled: July 15, 1998Date of Patent: June 5, 2001Assignee: Danfoss A/SInventor: Ulrik Darling Larsen
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Patent number: 6237331Abstract: The invention relates to a hydraulic steering arrangement (1) with a housing (4), in which an inner control slide (7) and an outer control slide (6) are arranged to be mutually rotational, forming together a variable flow path device between a supply connection device (P, T) and a working connection device (L,R), at least one pressure chamber (17) being arranged between two working slides (15, 16), connected with both control slides (6, 7), the volume change of said pressure chamber (17) causing the relative displacement, and with a measuring motor (10). In such steering arrangements a simple an inexpensive way of realizing a remote control principle is desired. For this purpose, an intermediary plate (14) is arranged between the measuring motor (10) and the control slides (6, 7), in which plate at least one fluid channel (18, 19) is arranged to form at least one part of a connection from the pressure chamber (17) to the outside.Type: GrantFiled: November 3, 1999Date of Patent: May 29, 2001Assignee: Danfoss A/SInventor: Ole Vincentz Sørensen
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Patent number: 6227833Abstract: There is disclosed a hydraulic or pneumatic machine having a first displacement element (8) that is rotatable about an axis of rotation connected to a shaft (10) so as to rotate therewith, which shaft is mounted rotatably in a housing (2), and co-operates with a second displacement element (9). The structure of such a machine is to be improved. For that purpose, the housing (2) has a pocket (3) in which the displacement elements (8, 9) are so arranged that the housing (2) covers the displacement elements (8, 9) axially on both sides (4, 5) at least in a working region and in the circumferential direction over a maximum of 180°.Type: GrantFiled: October 12, 1999Date of Patent: May 8, 2001Assignee: Danfoss A/SInventors: Peter Frøslev, Ingvard Mosby Madsen, Jørn Holger Klausen, Franz Thomsen