Patents by Inventor Johannes J. M. Schoenmakers

Johannes J. M. Schoenmakers has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4926278
    Abstract: A magnetic-tape-cassette apparatus having a magnetic head fixed in a head mount and carried on a head mounting plate. The head mount includes a cylindrical tape guide disposed to each side of the magnetic head air gap, in the direction of tape travel, a height limiter at one axial end of each guide surface, and an obliquely disposed control surface at the other end of each guide surface for biasing magnetic tape against the height limiters, so that the magnetic tape always has a constant orientation with respect to the air gap.
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: May 15, 1990
    Assignee: U.S. Philips Corporation
    Inventor: Johannes J. M. Schoenmakers
  • Patent number: 4615585
    Abstract: In an optical device an objective (11) can be moved relative to the frame (1) along its optical axis (13) in parallel guide means (3, 5) by means of an electromagnetic actuating device. The actuating device comprises first actuating means (21) and second actuating means (23) which are connected to the objective (11) and which cooperate with said first actuating means via an air gap (25). The first actuating means (21) are arranged in a mount (27) which is supported by a leaf-spring-shaped element (29) which is secured to the frame (1).
    Type: Grant
    Filed: January 9, 1985
    Date of Patent: October 7, 1986
    Assignee: U.S. Philips Corporation
    Inventors: Robert N. J. Van Sluys, Johannes J. M. Schoenmakers
  • Patent number: 4497008
    Abstract: A magnetic-tape cassette comprises a housing containing a magnetic tape, part of which extends across an opening in the front side of the housing which opening can be covered by a front cover of channel section which is pivotable on the housing at or near a corner thereof. In addition to being pivotable the front cover is also slidable on the housing when in the open position into a retracted position in which it extends along a side wall of the housing. In the retracted position the flanges of the channel-section front cover are received in, and substantially completely fill, recesses which are formed in the outer surfaces of the major walls of the cassette housing adjacent said side wall thereof.
    Type: Grant
    Filed: June 14, 1982
    Date of Patent: January 29, 1985
    Assignee: U.S. Philips Corporation
    Inventor: Johannes J. M. Schoenmakers
  • Patent number: 4484719
    Abstract: A magnetic-tape cassette having two reel hubs mounted for rotation in major walls, and a length of magnetic tape which is unwound from and taken up by the reel hubs, and guided along a first long side wall having apertures for a magnetic head. For supporting the edges of the tape in directions parallel to the axes of the reel hubs, at least two tape guides each have two height guides which, near that side of the tape guide which faces the first long side wall, converge from the direction of the first long side wall towards the adjacent reel. During operation, a plane tangent to the end portion of a height guide substantially coincides with a plane tangent to the inner side of the flange of the adjacent reel hub.
    Type: Grant
    Filed: October 25, 1982
    Date of Patent: November 27, 1984
    Assignee: U.S. Philips Corporation
    Inventor: Johannes J. M. Schoenmakers
  • Patent number: 4485420
    Abstract: A magnetic-tape cassette apparatus includes a magnetic head unit having a magnetic head with a head face and head gap defining a head gap plane. To each side of the head face, in the direction of tape transport, a tape guide is provided adjacent the head face and having a radius of curvature smaller than that of the head face. At one end of each tape guide a height limiter is arranged, having a limit surface facing the tape such that a line connecting the limit surfaces is perfectly perpendicular to the head gap plane. The apparatus includes a control member or surface for keeping a lateral edge of the tape constantly in contact with the limit surfaces during tape transport.
    Type: Grant
    Filed: April 12, 1982
    Date of Patent: November 27, 1984
    Assignee: U.S. Philips Corporation
    Inventor: Johannes J. M. Schoenmakers
  • Patent number: 4468711
    Abstract: A tape recorder or player having a central drive wheel and pivotable fast mode and normal mode idler arms. A switching lever pivots from a rest position to a first operative position to permit central drive wheel rotation to swing the fast mode idler against either reel drive spindle, or to a second operative position to enable normal mode idler operation. The head slide is also coupled to the lever in the operating position, and a control device limits lever movement to the first position for fast mode use.
    Type: Grant
    Filed: November 2, 1981
    Date of Patent: August 28, 1984
    Assignee: U.S. Philips Corporation
    Inventors: Johannes J. M. Schoenmakers, Ghislanus M. A. M. Aldenhoven
  • Patent number: 4451862
    Abstract: A tape recorder or player with automatic azimuth control, utilizing a single pieozoelectric element inside the head's magnetic shield. A bimorph has one end rigidly connected to the head and the other end rigidly connected to the head support, for pivoting the head about an axis in line with the head gap.
    Type: Grant
    Filed: December 29, 1982
    Date of Patent: May 29, 1984
    Assignee: U.S. Philips Corporation
    Inventors: Albert M. A. Rijckaert, Henricus M. Ruyten, Johannes F. Hoefnagels, Johannes J. M. Schoenmakers
  • Patent number: 4434955
    Abstract: A magnetic tape cassette comprises a housing having an open front side and two adjacent reel hubs containing an amount of tape, a span of said tape extending along the front side; at one or at both corner points near the open front side front covers are pivotable between an open position, and a closed position which covers at least partly over the front opening; the span of the magnetic tape which extends along the open front side can be moved between an active position outside the housing and an inactive position in which the tape is disposed between the major walls of the housing. Each front cover is formed with a thrust portion which during the pivotal movement from the open position to the closed position presses against the span of magnetic tape which extends along the front side and thereby moves it from the active position to the inactive position.
    Type: Grant
    Filed: June 7, 1982
    Date of Patent: March 6, 1984
    Assignee: U.S. Philips Corporation
    Inventor: Johannes J. M. Schoenmakers
  • Patent number: 4329723
    Abstract: An apparatus for recording and/or reproducing signals on a magnetic tape, having an azimuth adjustment for the gap of the magnetic head. At least one fixed support on a head plate has a slotted opening for receiving the free end of a tab on the head support, to form a knife-edge bearing about which the head and support are pivoted. A tape guide is formed on the head support immediately adjacent the tab.
    Type: Grant
    Filed: February 13, 1980
    Date of Patent: May 11, 1982
    Assignee: U.S. Philips Corporation
    Inventor: Johannes J. M. Schoenmakers
  • Patent number: 4152735
    Abstract: A tape transport mechanism for tensioning a magnetic tape unwound from a first reel past one or more magnetic heads and wound onto a second reel. The tape transport has a rotatable capstan upstream from the magnetic heads and a capstan pressure roller which cooperates with the capstan, and a transport spindle downstream from the magnetic heads with an associated transport spindle pressure roller. The transport spindle is driven by a constant torque drive to stretch the tape between the capstan and the transport spindle over the magnetic heads.
    Type: Grant
    Filed: February 4, 1977
    Date of Patent: May 1, 1979
    Assignee: U.S. Philips Corporation
    Inventor: Johannes J. M. Schoenmakers