Patents Assigned to Durr Dental GmbH & Co. KG
  • Patent number: 5140355
    Abstract: An automatic continuous developing apparatus has processing chambers dynamically sealed by a pair of rollers. Flood tanks are located between the processing chambers and the outer tanks surrounding the latter. In a raised position the flood tanks maintain a liquid level above the conveyor rollers in the processing chambers, while in a lowered operating position they free the inlet and outlet opening of the processing chambers.
    Type: Grant
    Filed: January 30, 1990
    Date of Patent: August 18, 1992
    Assignee: Durr Dental GmbH & Co KG
    Inventors: Siegfried Haag, Joachim Korn
  • Patent number: 4836755
    Abstract: In a low capacity compressor, the shaft (20) of the drive motor carries a fan wheel (42) including a crank pin (46) formed integral therewith. The lower end of a connecting rod (62) is journalled on the crank pin (46). The portion of the fan wheel (42) opposing the crank pin (46) is formed with an arc shaped balancing rib (82) having an angular extension of 180.degree.. Precise balancing of the piston/fan wheel unit is obtained by cutting material from the initially oversized balancing rib (82) and/or cutting from the portion of the fan wheel (42) being opposed to the balancing rib (82) so that a balancing groove (102) is obtained.
    Type: Grant
    Filed: March 22, 1988
    Date of Patent: June 6, 1989
    Assignee: Durr Dental GmbH & Co KG
    Inventors: Klaus D. Nitsche, Johann P. Zsiga
  • Patent number: 4792661
    Abstract: Apparatus for adjusting the temperature of a plurality of liquids which includes temperature adjusting means having a corresponding plurality of separate flow paths, a pump arrangement for circulating the liquids through said separate paths and means for maintaining predetermined temperature differences between the liquids, wherein the temperature adjusting means includes a single temperature controlling member and a number of pipes which correspond in number to the number of separate flow paths for the liquids of which the temperatures are to be adjusted. The temperature controlling member and the pipes are interconnected in heat conducting so that the total thermal impedance between the first of said pipes and the temperature controlling member integrated from the inlet end to the outlet end of said first pipe differs from the corresponding total thermal impedance of at least a second of said pipes.
    Type: Grant
    Filed: March 17, 1986
    Date of Patent: December 20, 1988
    Assignee: Durr Dental GmbH & Co KG
    Inventors: Gerhard Schmidtchen, Mathias Muller
  • Patent number: 4753632
    Abstract: A device for separating fine particles of solid matter from waste fluid has a water ring pump (16, 44), an air separator (18, 60) and a solid bowl centrifuge (24, 30) which are arranged axially one behind the other in the aforementioned sequence and are driven by the motor shaft (28) of a common drive motor (12).
    Type: Grant
    Filed: November 25, 1986
    Date of Patent: June 28, 1988
    Assignee: Durr Dental GmbH & Co KG
    Inventors: Hans-Joachim Hofmann, Andreas Bollmann, Walter Durr
  • Patent number: 4663035
    Abstract: Apparatus for extracting air and solids from liquid suspensions thereof comprises a vessel assembly having three cylindrical superposed mutually co-axial chambers. Means are provided for introducing suspension into the uppermost chamber and guiding the same into a centrifuge located in the juncture between the intermediate and bottom chambers. Located beneath the centrifuge is a solids collecting vessel. Means are provided for discharging air and cleansed liquid from the vessel through outlet means therefor. The air outlet means is connected to a source of subpressure and the cylindrical chambers are detachably connected together with the aid of suitable fastener means. The uppermost chamber incorporates a dry section through which air is removed from the vessel, and the guide means is constructed to prevent suspension from entering this section.
    Type: Grant
    Filed: June 4, 1985
    Date of Patent: May 5, 1987
    Assignee: Durr Dental GmbH & Co. KG
    Inventor: Jan Rosander
  • Patent number: 4619009
    Abstract: Tooth cleaning apparatus comprises a drive and grip part and a brush part removably attached to the drive and grip part. The drive and grip part comprises a cylindrical casing housing an electric motor. The brush part comprises an elongate shank portion which is coaxial with the drive and grip part and is removably attached at its inner end to the cylindrical casing. At its outer end the shank portion has a bearing for a removable brush rotatable about an axis perpendicular to the shank portion. A drive shaft rotatable in the shank portion is connectable at one end with the motor and at the other end has gear teeth meshing with gear teeth on the brush. One or more tubes extending through the shank portion supply fluid to the vicinity of the brush.
    Type: Grant
    Filed: August 23, 1984
    Date of Patent: October 28, 1986
    Assignee: Durr-Dental GmbH & Co. KG
    Inventor: Otto Rosenstatter
  • Patent number: 4564374
    Abstract: A separator for incorporation into dental suction apparatus for separating from the suction stream liquid and solid materials coming from the mouth of a patient comprises a housing, a separation chamber in the housing, an inlet for the suction stream into the separation chamber and an outlet for cleaned suction air from the separation chamber. Below the separation chamber there is a smaller collecting chamber below which is a drainage chamber provided with a liquid-solid discharge opening. In the separation chamber there is a cyclone device into which the suction stream enters tangentially so as to provide a swirling movement. The suction air then passes up through a central opening defined by the cyclone means. Also in the separation chamber there is a rotating element in the form of a rotatable float having a stem extending up from the float and provided with vanes associated with the cyclone device so as to rotate the float.
    Type: Grant
    Filed: September 21, 1983
    Date of Patent: January 14, 1986
    Assignee: Durr-Dental GmbH & Co. KG
    Inventor: Hans-Joachim Hofmann
  • Patent number: 4529365
    Abstract: An oil-less gas compressor comprises at least one cylinder block mounted on a crankcase, the outer end of the cylinder block being closed by a cylinder head. A piston in the cylinder block bore is reciprocated by a motor-driven crankshaft in the crankcase. The cylinder blocks and cylinder heads are generally square in cross section. On all four sides of the cylinder block and cylinder head there are spaced cooling fins which extend in an axial direction. Axially extending cooling air passages between the fins communicated at their lower ends with the interior of the crankcase. Air drawn into the crankcase by a fan on the crank shaft flows into and through these cooling air passages to cool the cylinder block and head. In one corner portion of the cylinder block and head there is an integral axially extending suction bore containing a filter. In an adjacent corner portion of the cylinder block there is an axially extending compressed air bore.
    Type: Grant
    Filed: November 25, 1983
    Date of Patent: July 16, 1985
    Assignee: Durr-Dental GmbH & Co., KG
    Inventors: Peter Schutt, Klaus Nitsche, Horst Grindler, Hans-Joachim Hofmann
  • Patent number: 4428777
    Abstract: A process of cleaning the film transport rolls of developing apparatus having a transport system comprising a plurality of pairs of rolls for transporting the film from an inlet through successive aqueous baths and a drying section and out of a discharge, some of the rolls being above and others below the liquid level in the baths comprises passing lengthwise through the transport system of the apparatus a rectangular sheet of fleece material having fibers oriented parallel to one another and to the longitudinal edges of the sheet. The fibers are made of a material which is substantially free of swelling by the action of the baths of the developing apparatus. However, the liquid of the baths is absorbed in the interstices between the fibers of the fleece material so that as the cleaning material passes along the transport system it moistens those rolls which are above the liquid level and may have dried out. Any soluble impurities on such rolls are thereby dissolved.
    Type: Grant
    Filed: March 15, 1982
    Date of Patent: January 31, 1984
    Assignee: Durr-Dental GmbH & Co. KG
    Inventor: Mathias Muller
  • Patent number: 4411550
    Abstract: In a torque transmitting coupling between a cylindrical shaft and a female member having a bore to receive the shaft, the shaft has a secant face and the female member has a connecting bolt bore which intersects the shaft bore and faces the secant face of the shaft. A connecting bolt in the bolt bore of the female member has a secant face which tightly engages the secant face of the shaft. In one embodiment, the shaft axis, secant faces of the shaft and bolt and the bolt bore are all parallel. In another embodiment the axis of the bolt bore is inclined at a small angle to the secant face, the bolt being of wedge form. A screw extending through a hole in the female member and screwed into a tapped hole in the bolt is rotatable to move the bolt axially and thereby wedge the secant face of the bolt against the secant face of the shaft. The secant faces of the shaft and bolt may have intermeshing longitudinally extending serrations.
    Type: Grant
    Filed: August 28, 1981
    Date of Patent: October 25, 1983
    Assignee: Durr-Dental GmbH & Co., KG
    Inventors: Peter Schutt, Martin Bernhardt, Klaus Nitsche, Horst Grindler, Hans-Joachim Hofmann
  • Patent number: 4378151
    Abstract: Small apparatus for developing photosensitive materials, in particular table-top apparatus, comprises a housing divided by partitions into a plurality of processing stations, for example a developing station, a fixing station and a washing station. Each of the stations comprises a trough containing the respective processing liquid. The photosensitive material to be developed is conveyed by transport rolls from an inlet, through the successive stations and out of an outlet. Liquid in a trough is circulated by a device comprising a magnetic rotor which rotates in a submerged rotor housing in the trough and has inlet openings in its cover and a tangential outlet opening in its periphery. The rotor is rotated by a rotating magnetic field arrangement outside the trough. In one embodiment it comprises a motor-driven permanent magnet. In another, it comprises magnetic coils arranged in a circle and energized sequentially.
    Type: Grant
    Filed: May 13, 1981
    Date of Patent: March 29, 1983
    Assignee: Durr-Dental GmbH & Co., KG.
    Inventors: Mathias Muller, Gerhard Schmidtchen
  • Patent number: D264502
    Type: Grant
    Filed: March 31, 1980
    Date of Patent: May 18, 1982
    Assignee: Durr Dental GmbH and Co., KG
    Inventors: Mathias Muller, Gerhard Schmidtchen
  • Patent number: D271203
    Type: Grant
    Filed: February 27, 1981
    Date of Patent: November 1, 1983
    Assignee: Durr-Dental GmbH & Co., KG
    Inventors: Peter Schutt, Klaus Nitsche, Horst Grindler, Hans-Joachim Hofmann, Hans E. Slany