Patent Application
20090033447
1. Field of the Invention
The disclosed invention generally relates to an electromagnetic relay assembly incorporating a uniquely configured armature assembly. More particularly, the disclosed invention relates to an electromagnetic relay assembly having a magnetically actuable rotor assembly for linearly displacing a switch actuator.
2. Brief Description of the Prior Art
Generally, the function of an electromagnetic relay is to use a small amount of power in the electromagnet to move an armature that is able to switch a much larger amount of power. By way of example, the relay designer may want the electromagnet to energize using 5 volts and 50 milliamps (250 milliwatts), while the armature can support 120 volts at 2 amps (240 watts). Relays are quite common in home appliances where there is an electronic control turning on (or off) some application device such as a motor or a light. The present teachings are primarily intended for use as a single pole, 120-amp passing electromagnetic relay assembly. It is contemplated, however, that the essence of the invention may be applied in multi-pole relay assemblies, having unique construction and functionality as enabled by the teachings of the single pole embodiment set forth in this disclosure. Several other electromagnetic relay assemblies reflective of the state of the art and disclosed in United States patents are briefly described hereinafter.
U.S. Pat. No. 6,046,660 ('660 Patent), which issued to Gruner, discloses a Latching magnetic relay assembly with a linear motor. The '660 Patent teaches a latching magnetic relay capable of transferring currents of greater than 100 amps for use in regulating the transfer of electricity or in other applications requiring the switching of currents of greater than 100 amps. A relay motor assembly has an elongated coil bobbin with an axially extending cavity therein. An excitation coil is wound around the bobbin. A generally U shaped ferromagnetic frame has a core section disposed in and extending through the axially extending cavity in the elongated coil bobbin. Two contact sections extend generally perpendicularly to the core section and rises above the motor assembly. An actuator assembly is magnetically coupled to the relay motor assembly. The actuator assembly is comprised of an actuator frame operatively coupled to a first and a second generally U-shaped ferromagnetic pole pieces, and a permanent magnet. A contact bridge made of a sheet of conductive material copper is operatively coupled to the actuator assembly.
U.S. Pat. No. 6,246,306 ('306 Patent), which issued to Gruner, discloses an Electromagnetic Relay with Pressure Spring. The '306 Patent teaches an electromagnetic relay having a motor assembly with a bobbin secured to a housing. A core is adjacently connected below the bobbin except for a core end, which extends from the bobbin. An armature end magnetically engages the core end when the coil is energized. An actuator engages the armature and a plurality of center contact spring assemblies. The center contact spring assembly is comprised of a center contact spring which is not pre bent and is ultrasonically welded onto a center contact terminal. A normally open spring is positioned relatively parallel to a center contact spring. The normally open spring is ultrasonically welded onto a normally open terminal to form a normally open outer contact spring assembly. A normally closed outer contact spring is vertically positioned with respect to the center contact spring so that the normally closed outer contact spring assembly is in contact with the center contact spring assembly, when the center contact spring is not being acted upon by the actuator. The normally closed spring is ultrasonically welded onto a normally closed terminal to form a normally closed assembly. A pressure spring pressures the center contact spring above the actuator when the actuator is not in use.
U.S. Pat. No. 6,252,478 ('478 Patent), which issued to Gruner, discloses an Electromagnetic Relay. The '478 Patent teaches an electromagnetic relay having a motor assembly with a bobbin secured to a frame. A core is disposed within the bobbin except for a core end which extends from the bobbin. An armature end magnetically engages the core end when the coil is energized. An actuator engages the armature and a plurality of movable blade assemblies. The movable blade assembly is comprised of a movable blade ultrasonically welded onto a center contact terminal. A normally open blade is positioned relatively parallel to a movable blade. The normally open blade is ultrasonically welded onto a normally open terminal to form a normally open contact assembly. A normally closed contact assembly comprised of a third contact rivet and a normally closed terminal. A normally closed contact assembly is vertically positioned with respect to the movable blade so that the normally closed contact assembly is in contact with the movable blade assembly when the movable blade is not being acted upon by the actuator.
U.S. Pat. No. 6,320,485 ('485 Patent), which issued to Gruner, discloses an Electromagnetic Relay Assembly with a Linear Motor. The '485 Patent teaches an electromagnetic relay capable of transferring currents of greater than 100 amps for use in regulating the transfer of electricity or in other applications requiring the switching of currents of greater than 100 amps. A relay motor assembly has an elongated coil bobbin with an axially extending cavity therein. An excitation coil is wound around the bobbin. A generally U shaped ferromagnetic frame has a core section disposed in and extending through the axially extending cavity in the elongated coil bobbin. Two contact sections extend generally perpendicularly to the core section and rises above the motor assembly. An actuator assembly is magnetically coupled to the relay motor assembly. The actuator assembly is comprised of an actuator frame operatively coupled to a first and a second generally U-shaped ferromagnetic pole pieces, and a permanent magnet. A contact bridge made of a sheet of conductive material copper is operatively coupled to the actuator assembly.
U.S. Pat. No. 6,563,409 ('409 Patent), which issued to Gruner, discloses a Latching Magnetic Relay Assembly. The '409 Patent teaches a latching magnetic relay assembly comprising a relay motor with a first coil bobbin having a first excitation coil wound therearound and a second coil bobbin having a second excitation coil wound therearound, both said first excitation coil and said second excitation coil being identical, said first excitation coil being electrically insulated from said second excitation coil; an actuator assembly magnetically coupled to both said relay motor, said actuator assembly having a first end and a second end; and one or two groups of contact bridge assemblies, each of said group of contact bridge assemblies comprising a contact bridge and a spring.
It is an object of the present invention to provide an electromagnetic relay assembly having certain means for damping contact vibration intermediate contacts of the switching assembly. It is a further object of the present invention to provide an armature assembly having an axis of rotation and which rotates under the influence of the magnetic field created or imparted from an electromagnetic coil assembly. The armature assembly linearly displaces a switch actuator for opening and closing the switch assembly of the relay. To achieve these and other readily apparent objectives, the electromagnetic relay assembly of the present disclosure comprises an electromagnetic coil assembly, an armature bridge assembly, and a switch assembly, as described in more detail hereinafter.
The coil assembly essentially comprises a coil, a C-shaped yoke assembly, and a coil axis. The coil is wound around the coil axis, and the yoke assembly comprises first and second yoke arms. Each yoke arm comprises an axial yoke portion that is coaxially alignable with the coil axis and together form the back of the C-shaped yoke assembly. Each yoke arm further, comprises a yoke terminus, which yoke termini are coplanar and substantially parallel to the coil axis.
The armature bridge assembly is rotatable about an axis orthogonally spaced from the coil axis and coplanar with the yoke termini. The armature bridge assembly thus comprises a bridge axis of rotation, a bridge, and an actuator arm. The bridge comprises a medial field pathway relative closer in proximity to the coil axis, a lateral field pathway relatively further in proximity to the coil axis, and longitudinally or axially spaced medial-to-lateral or lateral-to-medial field pathways (or transverse field pathways) extending intermediate the medial and lateral pathways. The actuator arm is cooperable with the lateral field pathway via a first end thereof and extends laterally away from the lateral field pathway.
The switch assembly essentially comprises switch terminals and a spring assembly between the switch terminals. The spring assembly is attached a second end of the actuator arm. The yoke termini are received intermediate the medial and lateral pathways. As is standard and well-established in the art, the coil receives current and creates or imparts a magnetic field, which magnetic field is directable through the bridge assembly via the yoke termini for imparting bridge rotation about the bridge axis of rotation and linearly displacing the actuator arm. The displaceable actuator arm functions to actuate the spring assembly intermediate an open contact position and a closed contact position, which closed contact position enables current to pass through the switch assembly via the switch termini.
Certain peripheral features of the essential electromagnetic relay assembly include certain means for enhancing spring over travel, which means function to increase contact pressure intermediate the switch terminals when the spring assembly is in the closed position. The means for enhancing spring over travel further provide means for contact wiping or contact cleansing via the enhanced contact or increased contact pressure. In other words, the enhanced conduction path through the contact interface may well function to burn off residues and/or debris that may otherwise come to rest at the contact surfaces. The means for enhancing spring over travel may well further function to provide certain means for damping contact bounce or vibration intermediate the first and second contacts when switching from the open position to the closed position.
Other objects of the present invention, as well as particular features, elements, and advantages thereof, will be elucidated or become apparent from, the following description and the accompanying drawing figures.
Other features of our invention will become more evident from a consideration of the following brief description of patent drawings:
Referring now to the drawings, the preferred embodiment of the present invention concerns an electromagnetic relay assembly 10 as illustrated and referenced in
The coil assembly 12 of the present invention preferably comprises a current-conductive coil 15 as illustrated and referenced in
It is contemplated that the rotatable armature assembly 13 of the present invention may be described as preferably comprising a rotor assembly 21 as generally illustrated and referenced in
It may be seen from an inspection of the noted figures that the rotor bracket 26 is attached or otherwise cooperatively associated with a first end of the actuator arm 22, and that the rotor plate 25 and the rotor bracket 26 (or portions thereof) are preferably oriented parallel to one another by way of the rotor housing 27. In this regard, it may be further seen that the first and second rotor magnets 23 are equally dimensioned and extend intermediate the rotor plate 25 and the rotor bracket 26 for simultaneously and equally spacing the rotor plate 25 and the rotor bracket 26 and for further providing a guide way or pathway for so-called Lorenz current or magnetic flux to be effectively transversely directed across the rotor or bridge assembly 21 as diagrammatically depicted in
In this last regard, it is contemplated that the armature assembly 13 may be thought of as an armature bridge assembly, which bridge assembly comprises a bridge axis of rotation (akin to the armature axis of rotation 101) and a bridge in cooperative association with the armature arm 22. In this context, the bridge may be thought of or described as preferably comprising a medial pathway (akin to the rotor plate 25), a lateral pathway (akin to the rotor bracket 26), and longitudinally or axially spaced medial-to-lateral or transverse pathways (akin to the first and second rotor magnets 23. The armature arm 22 may thus be described as extending laterally away from the lateral pathway or rotor bracket 26 for engaging the switch assembly 14.
The rotor housing 27 essentially functions to receive, house, and position the first and second rotor magnets 23, the rotor plate 25 and the rotor bracket 26 to form the bridge like structure of the armature assembly 13. The rotor magnets 23 are uniformly directed such that like poles face the same rotor structure. For example, it is contemplated that the north poles of rotor magnets 23 may face the rotor bracket 26 (the south poles thereby facing the rotor plate 25) or that the south poles of rotor magnets 23 may face the rotor bracket 26 (the north poles thereby facing the rotor bracket).
The rotor housing 27 may well further comprise a pin-receiving aperture or bore for receiving the rotor pin 29 as may be generally seen from an inspection of
In this last regard, it will be recalled that the armature assembly 13 of present invention may be anchored or mounted by way of the rotor mount 30. Rotor mount 30 may be cooperatively associated with the relay housing 48 (i.e. anchored to the relay housing 48) for axially fixing the rotor pin 29, the fixed rotor mount 30 receiving and anchoring an upper end of the rotor pin 29 so as to enable users of the relay to effectively operate the electromagnetic relay assembly 10 of the present invention without the relay cover 49. The rotor mount 30 or bridge mount or means for mounting the rotor assembly or bridge assembly may thus be described as providing certain means for enabling open face operation of the electromagnetic relay assembly 10. It is contemplated, for example, that in certain scenarios a coverless relay assembly provides a certain benefit. For example, the subject relay assembly may be more readily observed during testing procedures. In any event, it is contemplated that the rotor mount 30 of the present invention enables cover-free operation of the electromagnetic relay assembly 10 by otherwise fixing the armature assembly 13 to the relay housing 48.
The switch assembly 14 of the present relay assembly 10 preferably comprises a first switch terminal assembly 31 as generally illustrated and referenced in
The triumvirate spring assembly 33 preferably comprises a second contact button 37 as illustrated and referenced in
It may be further seen that the second C-shaped aperture 46 is preferably concentric about the third contact-receiving aperture 45, and that the second C-shaped fold 47 has a certain second radius of curvature, which second radius of curvature is greater in greater in magnitude than the first radius of curvature (of the first C-shaped fold 44). The second spring 39 is sandwiched intermediate the first and third springs 38 and 40 via the second contact button 37 as received or extended through the contact-receiving apertures 41, 43, and 45. The first C-shaped fold 44 is concentric (about a fold axis) within the second C-shaped fold 47. The first and second contact buttons 34 and 37 or contacts are spatially oriented or juxtaposed adjacent one another as generally depicted in
It is contemplated that the first and second C-shaped apertures 42 and 46, and the end-located offset or bend 70 may well function to provide certain means for enhanced over travel for increasing contact pressure intermediate the first and second contact buttons 34 and 37. In this regard, the reader is further directed to
In other words, the material (preferably copper) of the spring elements having the C-shaped apertures is more readily and elastically deformable at the termini of the C-shaped apertures as at 50 in
Conduction through the contact buttons 34 and 37 is thus improved by way of the C-shaped aperture-enabled and/or enhanced over travel as generally depicted in
From an inspection of
The rotor bracket 26 thus functions to linearly displace the actuator arm 22, which displaced actuator arm 22 functions to actuate the triumvirate spring assembly 33 from a preferred spring-biased open position (as generally depicted in
It is further contemplated that the electromagnetic relay according to the present invention may comprise certain means for defaulting to an open contact position during threshold terminal-based current conditions. In this regard, it is noted from classical electromagnetic theory that streaming charge carriers develop a magnetic field in radial adjacency to the direction of the carrier stream. The reader is thus directed to
While the above descriptions contain much specificity, this specificity should not be construed as limitations on the scope of the invention, but rather as an exemplification of the invention. For example, the invention may be said to essentially teach or disclose an electromagnetic relay assembly for enabling current to pass through switch termini, which electromagnetic relay assembly comprising a coil assembly, a bridge assembly, and a switch assembly. The coil assembly comprises a coil, a coil axis, and a C-shaped core. The coil is wound around the coil axis 100, and the coil axis extends 100 through the core as at 60 in
The bridge assembly comprises an axis of rotation as at 101 and a bridge as at 61 in
It is contemplated that the transverse pathways 65 provide certain field-diversion means for transversely diverting the magnetic field 102 relative to the coil axis 100 and magnetically inducing a torque, which magnetically induced torque functions to actuate the switch actuator 22. Said field diversion means may be further described as comprising certain field division means (there being two axis-opposing paths as at 66 in
The switch assembly as at 14 is further cooperable with the actuator arm 22, which actuator arm 22 is essentially a coupling intermediate the bridge assembly 61 and the switch assembly 14. The coil functions to create or impart a magnetic field as vectorially depicted at 102. The magnetic field 102 is directable through the bridge assembly 61 via the core termini 20 for imparting bridge rotation about the axis of rotation 101 via magnetically induced torque. The bridge rotation functions to displace the actuator arm 22, which displaced actuator arm 22 physically opens and closes the switch assembly 14. As is most readily understood in the arts, the closed switch assembly 14 enables current to pass therethrough.
The switch assembly 14 comprises certain spring means for enhancing spring over travel, said means for enhancing the closed switch position by way of increasing the contact pressure intermediate contact buttons 34 and 37. The spring means for enhancing spring over travel further provide contact wiping means, and vibration damping means. The contact wiping means are contemplated to effectively self-cleanse the switch assembly 14, and the vibration damping means function to damp contact vibration when switching from open to closed switch positions. The spring means for enhancing spring over travel may thus be said to enhance the closed switch position by increasing contact pressure intermediate the contacts, by maintaining a residue free contact interface, and by damping contact vibration when closing the contacts.
Although the invention has been described by reference to a number of embodiments it is not intended that the novel device or relay be limited thereby, but that modifications thereof are intended to be included as falling within the broad scope and spirit of the foregoing disclosure and the appended drawings. For example, the foregoing specifications support an electromagnetic relay assembly primarily intended for use as a single pole, 120-amp passing relay assembly. It is contemplated, however, that the essence of the invention may be applied in multi-pole relay assemblies, having unique construction and functionality in their own right, but which are enabled by the teachings of the single pole embodiment set forth in this disclosure.
