Snap-action Patents (Class 335/188)
  • Patent number: 11587750
    Abstract: Electromechanical relay constructions comprise an external housing, a pair of switchable electrical contacts disposed within the housing, an element for activating the pair of electrical contacts, and a temperature sensing element disposed within the housing adjacent the electrical contracts. The temperature sensing element provides a signal for determining the temperature within the relay housing. The relay may comprise two or more temperature sensing elements disposed within the housing a desired distance from one another. The temperature sensing element may be attached to a member or substrate disposed within the housing, may be attached to an existing internal structure of the housing, or may be attached to one of the contacts. The temperature sensing element may be selected from the group consisting of resistance temperature detectors, negative temperature coefficient thermistors, thermopile sensors, thermocouples, and combinations thereof.
    Type: Grant
    Filed: April 30, 2019
    Date of Patent: February 21, 2023
    Assignee: TE CONNECTIVITY SOLUTIONS GmbH
    Inventors: Alexander Raymond King, Marc Keener, Leigh Marolf
  • Patent number: 11043346
    Abstract: An electromagnetic relay includes a base frame including a main body supporting a fixed element, and a bottom plate having a plate thickness direction in an extending direction orthogonal to a central-axis line direction. An intermediate cover includes a covering plate facing a contact mechanism unit. An outer cover includes a top plate facing the bottom plate across the contact mechanism unit, and a first side plate extending from one end of the top plate and facing the covering plate. A first gap between the covering plate and the bottom plate in the extending direction and a second gap between the covering plate and the top plate in the extending direction are arranged to be substantially symmetric across the covering plate in the extending direction, the first gap and the second gap being on the first side plate.
    Type: Grant
    Filed: June 18, 2019
    Date of Patent: June 22, 2021
    Assignee: DENSO ELECTRONICS CORPORATION
    Inventors: Tomoko Ishikawa, Makoto Kamiya
  • Patent number: 10224154
    Abstract: This invention relates to a new magnetic proximity switch, comprising a shell, wherein a moving magnet that can move up and down is disposed on the upper part in the shell; a first terminal strip and a second terminal strip are fixedly disposed left and right in parallel at the bottom in the shell; a static contact is disposed on the second terminal strip; an elastic piece is disposed on the first terminal strip; a moving contact is disposed at the outer end of the elastic piece; an assistant rod is disposed at the middle part in the shell, an assistant portion is disposed at the inner end of the assistant rod, a limiting mechanism is disposed between the assistant rod and the shell, an elastic tongue piece is disposed on the elastic piece, and the outer end of the elastic tongue piece is disposed against the assistant portion.
    Type: Grant
    Filed: October 13, 2014
    Date of Patent: March 5, 2019
    Assignee: CHUANDONG MAGNETIC ELECTRONIC CO., LTD
    Inventors: Kewen Long, Tianbao Yan
  • Patent number: 9691577
    Abstract: Disclosed is a relay. The relay includes a first fixed contact, a second fixed, a movable contact, and a first magnet and a second magnet. The first contact part is disposed at a position which is closer to a distance to the second magnet than a distance to the first magnet, and the second contact part is disposed at a position which is closer to the distance to the first magnet than the distance to the second magnet. Accordingly, arcs are prevented from gathering at one position, and a contacting force between the movable contact and the fixed contacts is prevented from being reduced.
    Type: Grant
    Filed: May 11, 2015
    Date of Patent: June 27, 2017
    Assignee: LSIS CO., LTD.
    Inventor: Su Jung Lee
  • Publication number: 20120154077
    Abstract: An electromagnetic relay with at least one moveable contact spring, having an assigned normally-open contact, wherein the moveable contact spring is connected electrically-conductively to a first electrical terminal and the normally-open contact is connected electrically-conductively to a further electrical terminal, having a moveably mounted actuating element to move the moveable contact spring as a function of the current flowing through the relay in contact with the normally-open contact. The contact spring is equipped with two abutment surfaces, which are spatially separated from one another, and that the actuating element is equipped with two actuating surfaces, which are brought into active connection with the two abutment surfaces in order to move the contact spring.
    Type: Application
    Filed: December 13, 2011
    Publication date: June 21, 2012
    Applicant: TYCO ELECTRONICS AUSTRIA GMBH
    Inventor: Rudolf MIKL
  • Publication number: 20120133462
    Abstract: The electromagnetic contactor enables a reliable return to a pole open position without increasing the spring force of a return spring. In an electromagnetic contactor, an electromagnetic device having an exciting coil and a contact mechanism having a return spring are disposed in parallel, and the electromagnetic device and contact mechanism are linked by a drive lever. The electromagnetic device has a polarized electromagnet having a magnetic circuit that includes a permanent magnet generating a suction force that moves the contact mechanism to a pole open position side when the exciting coil is not energized. The drive lever is fixed to either one of the electromagnetic device or contact mechanism and contacts with the other with no gap at least when the contact mechanism is moved to the pole open position side. The return force of the contact mechanism is covered by the suction force of the permanent magnet.
    Type: Application
    Filed: June 14, 2010
    Publication date: May 31, 2012
    Applicant: Fuji Electric FA Components & Systems Co., Ltd.
    Inventors: Yasuhiro Naka, Toshikatsu Ohgami, Koji Okubo, Koetsu Takaya, Kenji Suzuki
  • Publication number: 20120092097
    Abstract: An electromagnetic switch includes: a stationary contact; a movable contact movably provided with respect to the stationary contact; a coil configured to move the movable contact to a side of the stationary contact by means of current conduction; and a shaft provided inside the coil such that the movable contact is provided at an end portion thereof, wherein a snap-fit portion having a pair of hooks disposed to face each other is provided at an end portion of the shaft, and the movable contact is fixed between the end portion of the shaft and the hook.
    Type: Application
    Filed: October 12, 2011
    Publication date: April 19, 2012
    Inventor: Yeon Soon CHOI
  • Publication number: 20120075044
    Abstract: An electromagnetic relay includes a coil, a movable member, first and second fixed contact supports each having first and second fixed contacts, and a movable body having first and second movable contacts. A third fixed contact is arranged on the second fixed contact support at a position away from a line passing through the first and second fixed contacts, and a third movable contact is arranged on the movable body. When the movable member is driven by electromagnetic force of the coil, the movable contacts contact the fixed contacts at a contact portion between the first fixed contact and the first movable contact, a contact portion between the second fixed contact and the second movable contact, and a contact portion between the third fixed contact and the third movable contact.
    Type: Application
    Filed: November 30, 2011
    Publication date: March 29, 2012
    Applicant: ANDEN CO., LTD.
    Inventor: Masanao SUGISAWA
  • Publication number: 20110241809
    Abstract: In an electromagnetic relay, length from a movable contact to an end portion of a movable element on a first end side is set greater than length from the movable contact to another end portion of the movable element on a second end side opposite to the first end side. A direction of a Lorentz force acting on a portion of the movable element from the movable contact to the end portion of the movable element on the first end side is conformed to a direction for bringing fixed contacts and movable contacts into contact with each other. Thus, separation between the movable contacts and the fixed contacts due to an electromagnetic repulsive force can be inhibited.
    Type: Application
    Filed: March 24, 2011
    Publication date: October 6, 2011
    Applicant: ANDEN CO., LTD.
    Inventors: Masanao SUGISAWA, Shigeki FUJII, Hitoshi SUNOHARA
  • Publication number: 20110227676
    Abstract: A forced return solenoid that includes an electrical winding configured to create an electromagnetic field when electrical current flows through the winding, an electrical terminal configured to be connected to a source of electrical energy, and a moveable contact plate configured to be moved into contact with the electrical terminal. Embodiment of the forced return solenoid include a plunger configured to move axially in response to the electromagnetic field generated by the electrical winding. Movement of the plunger in one direction causes the moveable contact plate to connect with the electrical terminal. Movement of the plunger in the opposite direction causes an impact intended to break the connection between the moveable contact plate and the electrical terminal. Embodiments of the forced return solenoid further include a return spring configured to move the plunger in the second direction, wherein the impact means comprises a removable snap ring affixed to the plunger.
    Type: Application
    Filed: March 18, 2010
    Publication date: September 22, 2011
    Applicant: ISKRA AVTOELEKTRIKA D.D.
    Inventors: Ivan Cotic, Tomaz Bratus, Sebastjan Kobal
  • Publication number: 20100226060
    Abstract: Provided are a standby power cut-off device for automatically cutting off standby power according to power-on/off of an electronic product and a control method for the standby power cut-off device. By providing an electronic product to which the standby power cut-off device and the control method therefor are applied, the present invention can efficiently cut off standby power by using an existing general outlet without a need to use an outlet having a separate function added thereto. Moreover, the present invention automatically cuts off the standby power according to power-off of the electronic product without unplugging the electronic product, thereby maximizing user's convenience.
    Type: Application
    Filed: April 15, 2010
    Publication date: September 9, 2010
    Inventor: Chang-Ho Kim
  • Publication number: 20100123533
    Abstract: The relay has a movable first contact, a second contact, and an actuating element operatively connected with an armature of the relay. The first contact is movable toward the second contact by the actuating element and dependent on a supply of current to the relay. A snap action spring connects the second contact to a housing of the relay. The second contact is positioned between two arrangements by the snap action spring.
    Type: Application
    Filed: November 13, 2009
    Publication date: May 20, 2010
    Inventor: Johannes Helmreich
  • Patent number: 7538646
    Abstract: A relay includes a magnetic system provided with an armature and a contact system provided with a first contact and a moveable second contact. An electrically insulating base plate is arranged between the magnetic system and the contact system and has an opening therein. First and second walls extend from the base plate and are arranged between the opening and the magnetic system or the opening and the contact system. An actuator extends between the armature and the contact system through the opening and transfers movement of the armature to the second contact to move the second contact into electrical engagement with the first contact. The actuator has a third wall that extends toward the base plate and between the first and second walls. The first, second, and third walls extend a leakage path of an electrical leakage current between the contact system and the magnetic system.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: May 26, 2009
    Assignee: Tyco Electronics Austria GmbH
    Inventor: Rudolf Mikl
  • Patent number: 7360294
    Abstract: A method of assembling an inductive proximity sensor maintains inductive coil wound bobbins in fixed relation to an inductive core within a housing. The method includes configuring two inductive coil wound bobbins with an integral ledge cantilevered from an inside surface thereof for forming a pocket under the integral ledge at a bottom of each bobbin; disposing each inductive coil wound bobbin around a corresponding leg of the inductive core; containing a foot of each core leg into the pocket of the corresponding bobbin; inserting each of two legs of a thruster element into a corresponding bobbin so that each leg rests upon the ledge of the corresponding bobbin; disposing the inductive core, inductive coil wound bobbins, and thruster element into the housing; disposing a spring element on a top surface of the thruster element; and compressing the spring element against the top surface of the thruster element.
    Type: Grant
    Filed: January 5, 2007
    Date of Patent: April 22, 2008
    Assignee: Simmonds Precision Products, Inc.
    Inventors: Robert D. LaClair, David Henry Crowne, Christopher Spagnoletti, Eric Carter
  • Patent number: 4578732
    Abstract: A wall socket type ground fault circuit interrupter having a pair of sockets, a reset button and a test button that are accessible from the front of the interrupter. The interrupter has latched snap-acting contacts and a novel latching relay structure for releasably maintaining the snap-acting contacts in a circuit making position. The snap-acting contacts permit all of the components including the monitoring toroids and the power supply to be respectively located and connected at the load side of the snap-acting contacts so that all of the circuits of the interrupter are deenergized when the contacts snap to a circuit opening position. The snap-acting contact mechanism and relay are provided with structures which provides the interrupter with a trip-free mode of contact actuation and accordingly a tease-proof snap-acting contact operation.
    Type: Grant
    Filed: December 14, 1983
    Date of Patent: March 25, 1986
    Assignee: Square D Company
    Inventors: Charles W. Draper, Terry E. Franks
  • Patent number: 4574260
    Abstract: A trip free manually and relay operated snap switch having movable contacts that are moved with a snap action to circuit interrupting and making positions in response to movement of a push button. The switch includes a member that transmits movement between the push button and a carrier and is releasably held in an operated position by a wire-like latch. The latch has portions extending in slots in a plate that is movable by a solenoid operated plunger and portions having a sliding connection with a structure that is moved by the button to permit relative movement along two axes between the button operated structure and the solenoid operated structure.
    Type: Grant
    Filed: December 14, 1983
    Date of Patent: March 4, 1986
    Assignee: Square D Company
    Inventor: Terry E. Franks
  • Patent number: 4521757
    Abstract: A high speed electromagnetically actuated electromechanical switch is provided by a bistable electric snap blade operated by an electromagnetic actuator. A magnetically permeable yoke directs the flux paths of a pair of coaxial coils. An armature plunger shuttles axially reciprocally in the coils between first and second positions. The snap blade has a pair of cantilever arms extending towards each other to engage the armature plunger in the gap therebetween for lateral flexing actuation. Energization of a given coil provides a primary flux path around that coil through the yoke and the armature plunger, and provides a secondary flux path around both coils through the yoke and the armature plunger. The primary flux path force around either coil is always stronger than the secondary path.
    Type: Grant
    Filed: August 9, 1982
    Date of Patent: June 4, 1985
    Assignee: Eaton Corporation
    Inventors: Jerome K. Hastings, James H. Bigelow, Robert L. Pearson
  • Patent number: 4499345
    Abstract: A snap switch having an activating plunger which, when depressed, establishes an operative connection with a return spring, and causes the tensioning of a spring force accumulator. A ferromagnetic anchor is mounted pivotable about an axis running at right angles to the direction of the plunger. The anchor forms a jump member and is a component of a magnetic clamp arrangement containing a permanent magnet. The anchor activates at least one movable contact. The jumping action is initiated in both switching directions by the creation of an air gap between the anchor and its respective abutting surface in the magnet clamp. The magnetic clamp arrangement is formed by at least one yoke by way of which a magnetic circuit is closed in both positions of the anchor.
    Type: Grant
    Filed: November 19, 1982
    Date of Patent: February 12, 1985
    Assignee: SDS-Elektro G.m.b.H.
    Inventor: Bernhard Dietrich
  • Patent number: 4471179
    Abstract: A quick-break snap switch having an activating plunger which, when depressed, establishes an operative connection with a return spring and causes the charging of a spring force accumulator. A ferromagnetic anchor is mounted pivotable about an axis running at right angles to the direction of the plunger activation. The anchor forms the jump member and is a component of a magnetic clamp arrangement containing a permanent magnet. The anchor activates at least one movable contact. The jumping action is initiated in both switching directions by the creation of an air gap between the anchor and its respective abutting surface in the magnet clamp. The magnetic clamp arrangement contains at least one yoke by means of which a magnetic circuit is closed in both positions of the anchor.
    Type: Grant
    Filed: November 19, 1982
    Date of Patent: September 11, 1984
    Assignee: SDS Elektro GmbH
    Inventor: Bernhard Dietrich
  • Patent number: 4471180
    Abstract: Electrical multi-circuit switch apparatus includes a flat flux plate and a pyramid-shaped magnet having a base and three or more triangular faces defining intersecting edges, outer edges and an apex. The flux plate is fixed in a molded base in a depression with substantially vertical walls and electrical terminals having portions on said walls. The magnet carries spring arm contacts on its outer edges and is free to rotate, with respect to the flux plate, about whichever intersecting edge contacts the flux plate between stable positions in each of which one of said faces abuts the flux plate for maximum magnetic attraction. The movement is initiated by a downward force at a predetermined location on the base of the magnet and occurs with a magnetic snap action, moving said spring arm contacts in a vertical rocking motion to change the electrical connections between said terminals in a predetermined manner. The apparatus is shown in an automotive exterior lamp control.
    Type: Grant
    Filed: May 19, 1983
    Date of Patent: September 11, 1984
    Assignee: General Motors Corporation
    Inventors: Allen K. Schwartz, Billy R. Jones
  • Patent number: 4323868
    Abstract: A circuit breaker comprising an electrically insulating housing, an overcurrent sensor in the housing, a stationary and a movable contact in the housing, and a latch mechanism coupled to the movable contact. The latch mechanism is tripped in response to a sensed overcurrent; an overcenter spring is coupled to the movable contact for opening and closing the contacts with a snap action when the latch mechanism is tripped. An elongated handle member extends through a handle opening in the housing and is movable axially between a contacts open position and a contacts closed position. Handle link means couples the handle member to the latch mechanism and translates a longitudinal movement of the handle member into a rotational movement of the handle link to urge the latch mechanism into the contacts closed position.
    Type: Grant
    Filed: October 17, 1980
    Date of Patent: April 6, 1982
    Assignee: North American Philips Controls Corp.
    Inventor: George S. Harper
  • Patent number: 4314217
    Abstract: A locking device includes a housing, a plunger slidably supported in the housing for displacement in a first direction between two end positions and an electromagnet disposed in the housing and having a solenoid and an armature displaceable in a second direction by the force of a magnetic field generated upon energization of the solenoid and a coupling arrangement for operatively connecting the armature with the plunger for affecting the position of the plunger dependent upon the position of the armature. The coupling arrangement comprises a switch-over device which has two stable end positions and which is force-transmittingly connected to the plunger.
    Type: Grant
    Filed: August 1, 1979
    Date of Patent: February 2, 1982
    Assignee: Ellenberger & Poensgen GmbH
    Inventor: Fritz Krasser
  • Patent number: 4291291
    Abstract: A circuit breaker incorporates a collapsible telescoping linkage installed between its control handle and electrical contacts. The collapsible telescoping linkage is normally locked in an extended position to open and close the contacts as the control handle is moved between its off and on positions. The circuit breaker includes an electromagnetically operated armature operable in response to an overload condition to unlock the collapsible telescoping linkage to allow the linkage to collapse and instantaneously break the contacts. Thereafter, when the control handle moves to its off position, the linkage is locked in its extended position so that upon subsequent movement of the control handle to its on position the circuit breaker is automatically reset.
    Type: Grant
    Filed: September 18, 1979
    Date of Patent: September 22, 1981
    Assignee: North American Philips Controls Corp.
    Inventor: Donald K. Merchant
  • Patent number: 4270108
    Abstract: An improved two position control switch includes a spring biased pivoting armature with a projecting cantilever spring wire. The spring wire can be flexed in a direction transverse to the pivoting movement of the armature. The spring wire flexes to cooperate with a cam track thereby retaining the armature in one of two stable positions. Switching between positions occurs in response to pulse signals to the armature coil.
    Type: Grant
    Filed: December 10, 1979
    Date of Patent: May 26, 1981
    Assignee: Guardian Electric Manufacturing Company
    Inventor: William W. Wright
  • Patent number: 4258344
    Abstract: A small-sized power relay for automatic control of an air conditioner in response to the signal from an electronic thermostat. This relay, being operative in response to an ultra low current from the electronic thermostat, is instrumental in switching on and off the large current used in air-conditioning. Further, the manufacturing cost is substantially reduced.
    Type: Grant
    Filed: July 12, 1979
    Date of Patent: March 24, 1981
    Assignee: Kabushiki Kaisha Saginomiya Seisakusho
    Inventor: Ichiro Nishimi
  • Patent number: 4117285
    Abstract: Disclosed is a snap action circuit breaker with a compact one piece steel frame in a two part, telescoping molded circuit breaker case. The compact construction is combined with a symmetrical toggle actuator to provide a pleasing appearance suitable for mounting at readily accessible and visible locations on the front of an instrument panel. A variety of handle constructions are usable with the same basic mechanism. By providing a snap actuated contact construction with substantial overcurrent trip delay the device combines the best features of modern manual switches and circuit breakers so that it is in effect a manual switch with nuisance free over-current trip protection.
    Type: Grant
    Filed: August 19, 1977
    Date of Patent: September 26, 1978
    Assignee: Airpax Electronics Incorporated
    Inventor: George Sullivan Harper
  • Patent number: 4081642
    Abstract: An improved switch construction is provided having an overcenter-toggle mechanism for effecting the actuation of the one or more movable contacts of the switch. A pivotally-mounted operating lever carries one end of a toggle-tension spring, the other end of which is pivotally connected to the knee-joint pivot of a pair of pivotally-connected toggle links. The line of action of the force of the toggle-tension spring is such as to effect a straightening, or a collapsing of the pivotally-connected toggle-links, to thereby effect, respectively, a closure of the switch contacts, or an opening operation thereof.Preferably, a releasable rotatable support, or trigger is provided for the pivotal connection of one of the toggle links, so that a remote tripping operation is possible by an unlatching of the releasable support, which normally provides a stationary pivot for the toggle linkage of the mechanism.
    Type: Grant
    Filed: November 19, 1975
    Date of Patent: March 28, 1978
    Assignee: Westinghouse Electric Corporation
    Inventors: James O. Rexroad, Louis N. Ricci
  • Patent number: 4003010
    Abstract: When the electromagnet (relay) is energized, the plunger is pulled into the coil against the bias of the plunger spring. The pin projecting laterally from the plunger is captive in the opening in the cam pivoted on the frame. The pin moves down and strikes a ramp portion in the cam and is deflected to the bottom of the notch where it impacts the cam and rotates it to a position in which the cam surface actuates the switch actuator. The internal switch spring acting on the actuator exerts force on the cam surface and cooperates with the contour to hold the cam in either position. When the coil is de-energized, the plunger moves out and the pin is deflected by the return guide surface of the frame to pass to the opposite side of the cam centerline and into position to actuate the cam in the opposite sense when the coil is again energized.
    Type: Grant
    Filed: December 2, 1975
    Date of Patent: January 11, 1977
    Assignee: The Singer Company
    Inventors: George F. Kuchuris, Kenji Yatsushiro
  • Patent number: 3980979
    Abstract: The invention relates to magnetically operated electric switches of the kind comprising a magnet which is pivotally mounted and is arranged to rock to and fro with a snap action under the influence of an adjacent relatively movable magnetic actuator, and at least one switch contact which is moved between two end positions relatively to one or more complementary switch contacts upon rocking of the magnet. The magnet is a bar magnet fixed in a pivoted carrier which forms one link of an over center spring toggle acting on a flexible leaf which carries the movable contact or contacts.
    Type: Grant
    Filed: March 21, 1975
    Date of Patent: September 14, 1976
    Assignee: Bestobell Mobrey Limited
    Inventors: Paul E. Prosser, Alan F. J. Hookway
  • Patent number: 3942145
    Abstract: A snap-action switch moves a spring-biased, movable contact against a stationary contact. The switch includes a toroidal permanent magnet mounted loosely on a nonmagnetic, self lubricating plunger. The magnet is normally magnetically attracted to and adjacent to both a keeper and an armature, the armature being fixed to the plunger. The plunger slides through the keeper which also mounts the switch to a keyboard. A finger-engageable button is moved toward the keyboard to store sufficient potential energy in a spring to move the plunger and suddenly break the magnetic attraction, thereby providing a tactile snap-action. Plunger movement moves the movable contact in spring-versus-spring fashion until the contacts engage. Facilities are provided to minimize contact bounce, to maintain the magnet in a preferred position during plunger movement, to ensure self-aligning of the magnet with the keeper and the armature, to minimize contact damage and to optimize the tactile "feel" of the switch.
    Type: Grant
    Filed: September 3, 1974
    Date of Patent: March 2, 1976
    Assignee: Teletype Corporation
    Inventor: Bernard J. Sobczak
  • Patent number: 3934215
    Abstract: Disclosed is a switch housing having a cylindrically shaped cavity therein. An armature within the housing has a generally cylindrical shape and is movable with respect to the housing between two stable or quiescent positions. One end of the armature has a substantially hemispherical depression and forms, in combination with a matching depression in the base, a substantially spheroid portion of a chamber. Extending radially from the segment of the sphere within the base are two frusto-pyramidal depressions which extend downwardly to and in tangency with the spheroid segment in the base. Electrical conductors are adjacent the frusto ends of the pyramids and extend out of the base. Mercury is placed in the spheroid portion of the chamber. The armature has a collar of steel extending axially. A toroidal magnet is placed about the exterior of the cylindrical housing. A magnetically responsive keeper is secured to the housing top. The magnet is held by the metal keeper secured to the top of the housing.
    Type: Grant
    Filed: May 28, 1974
    Date of Patent: January 20, 1976
    Assignee: Inflo Systems, Inc.
    Inventors: Donald S. Rich, Norman Rudnick
  • Patent number: RE31690
    Abstract: Disclosed is a snap action circuit breaker with a compact one piece steel frame in a two part, telescoping molded circuit breaker case. The compact construction is combined with a symmetrical toggle actuator to provide a pleasing appearance suitable for mounting at readily accessible and visible locations on the front of an instrument panel. A variety of handle constructions are usable with the same basic mechanism. By providing a snap actuated contact construction with substantial overcurrent trip delay the device combines the best features of modern manual switches and circuit breakers so that it is in effect a manual switch with nuisance free over-current trip protection.
    Type: Grant
    Filed: September 17, 1980
    Date of Patent: October 2, 1984
    Assignee: No. American Philips Corp.
    Inventor: George S. Harper