Worm And Helical Patents (Class 74/458)
  • Patent number: 4630497
    Abstract: A worm and meshing worm gear are provided. The worm has a central cylindrical portion, and tapered portions at either end thereof. The angle of taper of the two tapered portions is the same, but in different directions. The angle of taper is substantially equal to 360 degrees divided by the number of teeth in the worm gear. Contact between the worm and gear occurs over three times the number of teeth in which contact is obtained with a conventional cylindrical worm. The worm is capable of being formed by thread rolling.
    Type: Grant
    Filed: November 5, 1984
    Date of Patent: December 23, 1986
    Assignee: Wedgtrac Corporation
    Inventor: Bertel S. Nelson
  • Patent number: 4619596
    Abstract: A parallel and outer axial rotating piston compressor comprises at least one driven helical main rotor and one auxiliary rotor meshing therewith. The main rotor includes tooth surfaces comprising layered circular helicoids defined by the helical generation of a circle whose plane is perpendicular to the rotor axis.
    Type: Grant
    Filed: October 12, 1982
    Date of Patent: October 28, 1986
    Assignee: Technika Beteiligungsgesellschaft mbH
    Inventor: Karl-Heinz Dammann
  • Patent number: 4615422
    Abstract: A coupling between a continuously rotating input shaft and a selectively rotatable output shaft has a friction type transition clutch operative to accelerate the output shaft to synchronous speed and to permit controlled deceleration of the output shaft to rest and a spline type direct clutch parallel to the transition clutch engageable at synchronous speed to directly couple the input and output shafts. The spline clutch includes an input member having an input spline with a pressure face at a first helix angle, an output member having an output spline with a pressure face at a second, smaller helix angle, and a longitudinally shiftable intermediate member having a spline with a first pressure face at the first helix angle and a second pressure face at the second helix angle. The difference in helix angles effects circumferential separation between the output spline pressure face and the intermediate member spline second pressure face before the two splines separate longitudinally.
    Type: Grant
    Filed: January 14, 1985
    Date of Patent: October 7, 1986
    Assignee: General Motors Corporation
    Inventor: Glenn W. Thebert
  • Patent number: 4602521
    Abstract: A rack and pinion steering gear of the kind in which a helical pinion engages a rack mounted in bearings, the rack being supported opposite the pinion by a spring loaded half round support journal, the spring acting to hold the pinion in contact with the teeth of the rack which are formed in such a manner as to provide in about the center of the rack a "ramp" in which there are tooth gaps of varying height providing a variation of slack free mesh center distance between the pinion and the rack, the maximum mesh center distance occurring in the mid travel portion of the rack and lesser mesh center distances occurring in positions of travel of the rack either side of the travel position of the present invention being characterized by the fact that the tooth gaps concerned are formed in such a manner as to form a ramp extending across the rack at an angle substantially the same as the angle made by the pinion axis with the rack axis whereby the possibility of an uneven distribution of the load between the teeth
    Type: Grant
    Filed: August 26, 1985
    Date of Patent: July 29, 1986
    Assignee: Arthur Ernest Bishop
    Inventors: Arthur E. Bishop, Klaus J. Roeske
  • Patent number: 4589299
    Abstract: A reduction motor shaft used, for example, in a wiper motor is disclosed, which is provided with screw type double worms constituting a reduction mechanism part. In this reduction motor shaft, right-handed and left-handed screw type worms are coaxially formed in one end side of the shaft as plural-thread screws at a linked state of tooth profiles of both worms, and further an annular protrusion is formed in a threading boundary between the worms.
    Type: Grant
    Filed: June 22, 1984
    Date of Patent: May 20, 1986
    Assignee: Jidosha Denki Kogyo Kabushiki Kaisha
    Inventors: Kyoji Kobayashi, Atsushi Inagaki
  • Patent number: 4586394
    Abstract: A lead screw positioner (10) is described, which has extremely low noise, including a nut (12) lying about a lead screw (14) and means for flowing gas under pressure between the nut and screw to keep them slightly spaced. The nut forms a plenum chamber (34) which receives pressured air, and has several holes (32) leading from the chamber to the clearance space (20) between the nut and screw to apply pressured air thereto. The nut and screw are devoid of direct sealing contact, so the pressured gas flows from the holes and axially along the screw to the end of the nut, where the gas flows into the environment.
    Type: Grant
    Filed: July 30, 1982
    Date of Patent: May 6, 1986
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Gerald S. Perkins
  • Patent number: 4576058
    Abstract: The present invention discloses a worm assembly comprising a first shaft; a second shaft coaxial to the first shaft, and a cylindrical worm made of hard metal and disposed between both shafts. Said first shaft is provided at the center of its end with a bolt which is closely fitted into the inner periphery of the worm and projects toward the second shaft. Said second shaft is provided at the center of it with a screw hole into which a screw portion of the bolt is screwed. Said worm is fixed unrotatably to both shafts by brazing or the others.
    Type: Grant
    Filed: May 14, 1984
    Date of Patent: March 18, 1986
    Assignee: Kabushiki Kaisha Nikken Kousakusho
    Inventor: Masakazu Matumoto
  • Patent number: 4541296
    Abstract: A gear wheel engages a driving worm gear with teeth which have a face with a curved portion. As a result, the circumference of the gear wheel has a portion which extends around the worm gear to increase the tooth contact area between the gear wheel and the worm gear. The gear wheel provides flexible support for the teeth. When a driving load is applied between the worm gear and the gear wheel, the gear wheel is flexed and the stepped portion of the face helps to maintain tooth contact area.
    Type: Grant
    Filed: July 18, 1983
    Date of Patent: September 17, 1985
    Assignee: Ford Motor Company
    Inventor: Harry H. Oyafuso
  • Patent number: 4478103
    Abstract: A worm (10) and worm gear (12) mechanism in which the gear (12), in addition to its gear teeth (20), also has a helical thread (22) formed thereon. The helical thread (11) of the worm (10) conventionally meshes with the gear teeth (20) of the worm gear (12), rotation of the worm (10) causing a corresponding rotation of the gear (12). The gear (12) is fitted in a threaded hole (21) so that, as it is rotated by the worm (10), it is also caused to move along its longitudinal axis within the hole (21).
    Type: Grant
    Filed: May 22, 1981
    Date of Patent: October 23, 1984
    Assignee: AT&T Bell Laboratories
    Inventor: James M. Benjamin
  • Patent number: 4425815
    Abstract: A wormwheel (1) has teeth (2) over at least a portion of its periphery. The teeth (2) are shaped such that the pitch diameter (5) is greater at one face (3) of the wormwheel than the other and does not increase along the path of the tooth from said one face (3) to the other face (4). Because of this tooth shaping the wormwheel may be cast and is thus suitable for mass production. Wormwheels of this type are particularly, but not exclusively, suitable for use in valve actuators. In order to facilitate the casting process the wormwheel is formed with only one integral bearing (10) and has an internally splined opening (8) in which can be received a bearing sleeve (18) which may also be adapted to receive the valve stem within its own axial opening (21). A variety of bearing sleeves suitable for use with different valve stems may be provided for cooperation with the same wormwheel thereby eliminating the need for special adaptors and reducing the number of parts required to construct a range of valve actuators.
    Type: Grant
    Filed: October 10, 1980
    Date of Patent: January 17, 1984
    Assignee: Mastergear Company Limited
    Inventors: Colin F. Norton, Raymond G. Harvey
  • Patent number: 4342548
    Abstract: A tool having only an end cutting-edge carries out a first movement of penetration into a screw blank so as to produce a groove having flanks substantially parallel to the pinion axis. The tool-holder is angularly displaced with respect to the spindle which carries the screw blank. A second movement of tool penetration takes place while the relative displacement is progressively reduced in order to obtain an inclined flank which produces a V-shaped profile. The screw is intended to form part of a compression and expansion machine and to cooperate with at least one pinion having V-form teeth.
    Type: Grant
    Filed: December 5, 1979
    Date of Patent: August 3, 1982
    Assignee: Uniscrew Limited
    Inventor: Bernard Zimmern
  • Patent number: 4226136
    Abstract: A compact drive assembly has a skew axis input gear set and a parallel axis output gear set. The input gear set includes a pinion having at least one helical thread thereon which drivingly engages a face gear. The face gear of the input gear set and the spur gear of the output gear set are integrally molded of a suitable plastic material forming a cluster gear. The output gear of the output gear set has a tooth configuration which is compatible with that of the spur gear which drives it. The gear assembly is particularly adapted for use in a power operated automobile window actuator and has the following advantages over existing actuators: (a) 50% reduction in size and weight, (b) capable of performing much higher input/output reductions despite decreased size, (c) needs no brake since the assembly is self-locking, (d) can be used with a smaller high speed motor which is less expensive.
    Type: Grant
    Filed: May 24, 1979
    Date of Patent: October 7, 1980
    Assignee: Illinois Tool Works Inc.
    Inventors: Troy L. Porter, Rudolph J. Belansky
  • Patent number: 4221135
    Abstract: A postage meter attachment or conversion apparatus is disclosed that will effectively convert a manually lever settable postage meter into an electrically controlled postage meter. The conversion apparatus is easily assembled to and disassembled from a standard lever settable postage meter. Each lever of the meter is settable simultaneously. The motion of the drive mechanism of the conversion apparatus conforms to the arcuate motion of the meter setting levers, thus eliminating the need for precise alignment between the levers and the drive mechanism. The conversion apparatus can be used to make the mechanical meter compatible in an electrical environment containing equipment such as a computer, a digital scale, and other postage system processing devices.
    Type: Grant
    Filed: June 12, 1978
    Date of Patent: September 9, 1980
    Assignee: Pitney Bowes Inc.
    Inventor: Keith E. Schubert
  • Patent number: 4140445
    Abstract: Screw rotor machine comprising male and female rotors, where the profile of the flanks of the female rotor comprises portions inside and outside the pitch circle thereof, which portions at the point of intersection with the pitch circle have a common tangent and different radii of curvature and the profiles of the flanks of the male rotor inside the pitch circle have a generally straight section.
    Type: Grant
    Filed: March 28, 1977
    Date of Patent: February 20, 1979
    Assignee: Svenka Rotor Haskiner Aktiebolag
    Inventor: Cauritz B. Schibbye
  • Patent number: 4053263
    Abstract: Screw rotors for a screw compressor or expander incorporating improved screw profiles on both male and female rotors wherein certain mating portions of the two rotor screws have involute profiles to provide conjugate action of these screw portions with minimum sliding motion of such mating portions and with the remaining non-involute screw portions having generally circular arc profiles so that gear cutting and measuring techniques can be used in the production of such screw rotors.
    Type: Grant
    Filed: January 2, 1976
    Date of Patent: October 11, 1977
    Assignee: Joy Manufacturing Company
    Inventor: Robert A. Ingalls
  • Patent number: 4047449
    Abstract: The invention relates to gear drives. The globoid worm gearing comprises a cylindrical worm-wheel in mesh with a globoid worm. The side surfaces of the thread of said globoid worm are shaped so as to envelop the side surfaces of the worm-wheel teeth with the result that in the process of successive engagement of the worm thread with the worm-wheel teeth the worm thread makes a linear contact throughout the side surface of the worm-wheel teeth. Said globoidal gearing is capable of transmitting larger torques and possesses a greater kinematic accuracy than like-size modified globoid worm gears known in the prior art.A method of making the globoid worm is provided whereby the worm is generated through relative movements of the worm blank and a rotary cutter and thereafter the side surfaces of the worm thread are finished by honing. The cutting edges of the rotary cutter are located on a generating surface having the shape of the side surfaces of the cylindrical worm-wheel teeth.
    Type: Grant
    Filed: January 29, 1976
    Date of Patent: September 13, 1977
    Inventor: Valentin Alexeevich Popov
  • Patent number: 4028026
    Abstract: A screw-type gas compressor has a pair of meshing rotors each formed with a plurality of helical ribs. The flanks of the ribs of one of these rotors are generally convex and at least partially formed as involutes. The flanks of the ribs of the other rotor are generally concave and at least partially formed as involutes. These shapes are formed by the rack-generating process or by hobbing.
    Type: Grant
    Filed: June 9, 1975
    Date of Patent: June 7, 1977
    Assignee: Linde Aktiengesellschaft
    Inventor: Ernst Menssen
  • Patent number: 3945778
    Abstract: A machine for compressing or expanding fluids in which a globoidal worm, having a plurality of threads with crests circumscribed by a surface generated by a rectilinear line and in meshing engagement with at least one toothed pinion, cooperates with a casing having at least one low pressure port and at least one high pressure port located in the immediate vicinity of the pinion. Each of the pinion teeth is provided with two substantially rectilinear flanks, the flank located on the side of the pinion nearest the low pressure port when one tooth is engaged in the worm being longer than the flank of the same tooth which is located nearest the high pressure port.
    Type: Grant
    Filed: October 22, 1974
    Date of Patent: March 23, 1976
    Inventor: Bernard Zimmern
  • Patent number: 3942389
    Abstract: A worm gearing having a worm and worm gear in meshing engagement. The worm consists of a thread which is produced by winding a strandlike member into a helix configuration. The strandlike member has two rows of projections and recesses on opposite sides of the strand which, in the wound-up condition, engage the projections and recesses of the next adjacent row to thereby prevent a relative reciprocal shifting therebetween during use thereof.
    Type: Grant
    Filed: March 17, 1975
    Date of Patent: March 9, 1976
    Inventor: Heinz Jung