Patents by Inventor Frederick L. Lau

Frederick L. Lau 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: 5485673
    Abstract: An environmental connector formed by insert molding a thermoplastic rubber insert into a plastic cylindrical housing having an external shoulder adjacent to an exit aperture for the thermoplastic rubber to flow to an annular void in the cavity of the mold. In such manner, an annular ring such as a gasket or o-ring is formed by the insert molding process, and is connected as one piece with the thermoplastic rubber insert formed in the internal chamber of the housing. The housing is made of polypropylene and the thermoplastic rubber is Santoprene so the two materials stick together to hold the annular ring snugly against the shoulder. The insert of the female connector has a concentric opening to receive the housing of the male connector, and the concentric opening terminates in thin protrusion that is compressible to from an inner seal to prevent the ingress of moisture into the connectors.
    Type: Grant
    Filed: June 16, 1994
    Date of Patent: January 23, 1996
    Assignee: Switchcraft Inc.
    Inventor: Frederick L. Lau
  • Patent number: 5098317
    Abstract: An interlock device having a slip resistant feature. A strip conductor is disposed in a dielectric housing and is electrically connected to a tip terminal plug. The strip conductor has an angled end distal from the tip terminal plug. A spring clamp is disposed in the dielectric housing and is pivotally coupled thereto. The angled end of the strip conductor and the spring clamp are adapted for clamping a conductor wire therebetween. The spring clamp exerts pressure on the conductor wire to maintain it in a fixed position and in contact with the strip conductor and the tip terminal plug.
    Type: Grant
    Filed: December 31, 1990
    Date of Patent: March 24, 1992
    Assignee: Switchcraft Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4938717
    Abstract: An electrical jack of the composite prong type having a leading end portion comprising a tapered tip component of an axially extending tip contact member. The tapered tip component has a proximal end portion terminating in a circular flange which has first diameter and is integrally joined to a rod component of much smaller diameter through a reinforced length component of intermediate diameter. The reinforced length component has a cross sectional size designed for uniformly distributing impact stresses transmitted from the tapered tip component, and has a length greater than its intermediate diameter for minimizing impact stresses transmitted to the rod component. The reinforced length component is slidably installed in a cup-shaped dielectric bushing having a flanged open end portion abutting the circular flange of the tapered tip component. The cup-shaped bushing has an opposing closed end provided with a central aperture through which extends the rod component and an encircling dielectric sheath.
    Type: Grant
    Filed: October 2, 1989
    Date of Patent: July 3, 1990
    Assignee: Switchcraft, Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4874317
    Abstract: A channelized jackfield comprising a housing having therein a linear array of juxtaposed channels wherein respective assemblies of aligned printed circuit boards and connecting slab-like modules are slidably inserted edgewise from the front of the housing. Each of the assemblies includes an inverted L-shaped bracket of dielectric material having a vertical leg latchingly secured to a front edge portion of the printed circuit board and provided with a plurality of spaced notches through which respective terminal lugs extend insulatingly from the printed circuit board and externally of the housing. Also, each of the L-shaped brackets has a leg disposed substantially orthogonal to the vertical leg and carries on its upper surface a guide groove for slidably receiving the connecting module and guiding it into mating engagement with an aligned connector attached to the front edge portion of the printed circuit board.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: October 17, 1989
    Assignee: Switchcraft, Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4826455
    Abstract: A terminal contact assembly comprising a dielectric sleeve of flexible material having a midportion provided with a transverse integral partition wherein a keyway slot extends from an open end thereof communicating with a longitudinal slot in a defining wall portion of the sleeve, through a restricted portion of the keyway slot, to a larger closed end portion thereof centrally disposed in the partition. This assembly also comprises an elongated rigid contact of electrically conductive material having a midportion with an hour glass configuration including a narrow neck portion or key which is inserted laterally through the longitudinal slot in the sleeve and enters the open end of the keyway slot. The key is pressingly urged through the restricted portion of the keyway slot, by virtue of adjacent portions of the sleeve and the integral partition flexing momentarily to widen the restricted portion, and snaps into the larger closed end of the keyway slot thereby locking the contact axially within the sleeve.
    Type: Grant
    Filed: June 20, 1988
    Date of Patent: May 2, 1989
    Assignee: Switchcraft, Inc.
    Inventors: Arnold A. Case, Frederick L. Lau, Emma Basov
  • Patent number: 4826439
    Abstract: A self-latching lamp jack comprising first and second dielectric plates disposed in opposing relationship for forming respective opposing sides of the lamp jack. One of the opposing plates is provided with a plurality of interposed wall portions for forming a pair of lamp conductor receiving cavities adjacent one end of the lamp jack. Also, the self-latching lamp jack includes a pair of electrical contact members which are blade-like and are disposed edge-wise between the opposing dielectric plates. Each of the contact members has an end portion disposed in a respective one of the lamp conductors receiving cavities and a midportion provided with a pair of laterally extended tabs which protrude into respectively aligned slots in the plates. The contact members have opposing terminal end portions which extend out of another end portion of the lamp jack.
    Type: Grant
    Filed: March 2, 1987
    Date of Patent: May 2, 1989
    Assignee: Switchcraft, Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4820200
    Abstract: A jack module having a relatively thin substantially rectangular dielectric housing having collared plug receiving apertures on one end thereof. The housing has a mounting bar parallel with said end, and the mounting bar has a plurality of slots perpendicular with the end. A plurality of metal strips each having tabs extending from opposing edges are secured in a predetermined substantially parallel arrangement by inserting the tabs on one edge into said mounting bar and engaging a dielectric retaining bar with slots corresponding to the tabs on the opposite edges over the metal strips. Lifters having one end rotatably engaging the housing have opposite ends extending between metal strips to hold them in a predetermined alignment. Upon insertion or removal of plugs from said plug receiving apertures, the metal strips are permitted to move laterally with the lifters.
    Type: Grant
    Filed: February 13, 1987
    Date of Patent: April 11, 1989
    Assignee: Switchcraft, Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4797114
    Abstract: A printed circuit board assembly including a connector comprised of an elongated dielectric body and an elongated dielectric cap having aligned portions provided with respective cooperating latching devices for removably securing the cap to a rear surface of the body. The body and the cap are provided with aligned through-holes wherein respective electrical contact members are disposed and have protruding end portions extended from the rear surface of the cap. The cap has extending integrally from its rear surface a wall with a surface which is orthogonal to the rear surface of the cap for forming a right-angle support structure wherein an end portion of a printed circuit board may be disposed. Also, the wall has an opposing surface which is disposed adjacent the protruding end portions of the contact members and which may be provided with a mandrel-like structure comprising a linear array of juxtaposed troughs formed in said opposing surface.
    Type: Grant
    Filed: March 2, 1987
    Date of Patent: January 10, 1989
    Assignee: Switchcraft, Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4784609
    Abstract: A jack module with a lamp assembly that is interconnected at the top front of a printed circuit board and has a bottom guide channel for slidably receiving a tri-jack. The printed circuit board has top and bottom forwardly extending necks which define a notch therebetween. The lamp assembly has a lamp housing with a hollow trunk and tow legs that provide upwardly and downwardly facing channels that slide onto the bottom and top edges of the top neck. The housing, which has a longitudinal bore holding a lamp, encases conductive strips which engage the lamp. The housing is locked to the neck by a retainer that has a boss that snaps into an aperture in the housing. A guide housing is similarly connected to the bottom neck. The lamp housing and bottom guide housing have facing guide channels which respectively receive top and bottom guide rails of the tri-jack in slidable engagement back to a printed circuit board connector in the notch.
    Type: Grant
    Filed: October 9, 1987
    Date of Patent: November 15, 1988
    Assignee: Switchcraft, Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4772562
    Abstract: A jackfield with a split front panel so that it can be removed to provide access to jack modules without breaking patch cord interconnections between jacks. Each jack module includes a printed circuit board having a lamp assembly and a tri-jack connected to the front and extending forwardly. The printed circuit boards are hard wired at the back of the jackfield and the printed circuit boards route the circuits to the tri-jack and the lamp assembly. To remove just a tri-jack, it is pulled forwardly after the split front panel is removed. A lateral bracket retains the printed circuit board to prevent it from being pulled forwardly. To remove the entire jack module, the wire wraps are disconnected from the back of the printed circuit board and the retaining bracket is removed. Then, the entire module can be slid forwardly in its guide slot.
    Type: Grant
    Filed: October 9, 1987
    Date of Patent: September 20, 1988
    Assignee: Switchcraft, Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4770639
    Abstract: A channelized jackfield assembly comprising a housing having an input portion wherein electrical jack modules are insertably disposed for forming a linear array of laterally spaced modules. Each of the modules has a slab-like body disposed with a narrow side uppermost and a thickness defining an aligned feedthrough channel wherein a printed circuit board is disposed on edge. The printed circuit board has a connector with a plurality of contact members disposed for insertable engagement with respective terminals extended from the adjacent end portion of the aligned module. The contact members of the connector are electrically connected through the printed circuit board to respective terminal conductors extended from an edge portion of the board and outwardly of the output portion of the housing. The printed circuit board may be slidably inserted into the output portion of the housing and between opposing wafer guides having in adjacent surfaces thereof respective linear arrays of laterally spaced channels.
    Type: Grant
    Filed: March 2, 1987
    Date of Patent: September 13, 1988
    Assignee: Switchcraft, Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4768961
    Abstract: A jackfield with front removable jack modules having lamp assemblies. Each jack module includes a printed circuit board having a lamp assembly and a tri-jack extending forwardly therefrom. Conductor pads at the rear of the printed circuit board removably engage contact spring terminals interconnected to lateral busses. One bus provides a voltage and the other provides ground for the lamp assembly. One of the circuit leads is routed through the jack so that when a plug is inserted into the jack, the lamp is lit. The module also has wire wrap lugs extending from the rear, and the wire wraps are disconnected before the module is removed to the front. Apparatus is also provided for retaining the module from forward movement when only the tri-jack is to be removed.
    Type: Grant
    Filed: October 9, 1987
    Date of Patent: September 6, 1988
    Assignee: Switchcraft, Inc.
    Inventor: Frederick L. Lau
  • Patent number: 4609795
    Abstract: An electrical switch comprising a moveable contact member resiliently biased to have an electrical contact portion thereof urged into spaced relationship with an electrical contact portion of a fixed member to open the switch and to have another protruding portion thereof disposed for pressure engagement with a cam surface of a reciprocally moveable actuator to urge the electrical contact portions of the contact member into electrical engagement with one another for closing the switch, and a dielectric barrier member carried on the actuator in predetermined positional relationship with the cam surface for movement out of a position between the electrical contact portions, before the switch is closed, to permit the electrical engagement of the contact portions with one another and for movement back into the position between the electrical contact portions, after the switch is open, to prevent the undesired effects of contact bounce.
    Type: Grant
    Filed: September 12, 1984
    Date of Patent: September 2, 1986
    Assignee: Switchcraft, Inc.
    Inventors: Vernon W. Lavigne, Keith A. Rosborough, Frederick L. Lau