US2166327A

US2166327A - Relay construction

Info

Publication number: US2166327A
Application number: US138942A
Authority: US
Inventors: Albert B Rypinski; Charles A Bay
Original assignee: METROPOLITAN DEVICE CORP
Current assignee: METROPOLITAN DEVICE Corp
Priority date: 1937-04-26
Filing date: 1937-04-26
Publication date: 1939-07-18
Anticipated expiration: 1956-07-18

Description

July 18, 1939. A. B. RYPINSKI El AL 2,166,327

RELAY CONSTRUCTION Filed April 26, 19:57 2 Sheeis-Sheet 1 IN V ENTORS Ami/P75 lQVP/A/SK/ fK/M/PMJA 54) ATTORNEY Patented July 18, 1939 UNITED STATES PATENT OFFICE I RELAY CONSTRUCTION New York Application April 26, 1937, Serial No. 138,942

4 Claims.

The invention herein disclosed relates to an electrical relay and in particular to a polarized relay of a construction that is particularly suitable for use in the control of street lights.

5 An object of this invention is to produce a relay of this type that is compact, sturdy in construction, durable and efficient in operation and that is comparatively inexpensive to manufacture.

These and other objects and certain advanl tages that will hereinafter more fully appear are obtained in accordance with this invention by providing a relay construction that includes a pivotally mounted electromagnet having a core extending from the electromagnet axially there- 15 of. Adjacent the end of the extended core of the electromagnet there is mounted a pair of electrical contacts that cooperate with fixed contacts to open and close a circuit. Intermediate the contacts mounted on the core of the electro- 20 magnet and the coil thereof, there is mounted a permanent magnet that is positioned such that the extension of the core of the electromagnet is between the pole faces of the permanent magnet. A keeper is secured to the electromagnet to preserve the magnetism thereof.

A relay so constructed, and embodying this invention is disclosed in the accompanying drawings in which;

Fig. 1 is a plan of the relay mounted in a 30 cabinet, the cover of the cabinet being broken away;

Fig. 2 is a transverse section taken along the line 22 of Fig. 1;

Fig. 3 is a transverse section taken along the 35 line 3-3 of Fig. 1; V

Fig. 4 is a fragmentary, sectional elevation taken on the line 4-4 of Fig. 1; and

Fig. 5 is a wiring diagram of the relay when used in connection with a street lighting sys-' 40 tern.

The relay disclosed in the drawings is, with its associated electrical appliances, mounted in a cabinet I that is provided with a cover 2. This cabinet, containing the relay and associated elec- 45 trical equipment, is adapted to be mounted on the post on which the electric light for street lighting is mounted. Within the cabinet I, there is a base 3 of insulating material secured to the rear wall of the cabinet. On this base of insulat- 50 ing material the relay and associated electrical equipment are mounted.

The relay consists of an electromagnet l having a cylindrical core 5 one end of which extends through a U-shaped yoke 6 and is secured thereto 55 by a nut I. The other end of the core 5 extends from the opposite end of the coil 4 axially of the coil. The end of this extended portion 5a. of the core is slotted longitudinally, the slot extending diametrically of the core. Within this slot, there is secured a tongue extension of an insulating 5 block 8 which block extends from the core and forms in effect a continuation thereof. On the insulating block 8 there is mounted a pair of contacts 9 and III, one on either side of the insulating block. The electrical contacts 9 and III are 10 mounted upon a bracket II which is a piece of resilient sheet metal bent as shown in Fig. 3 to form a base Ila which engages the underside of the insulating block 8 and diverging side arms I Ib and He. The contact 9 is mounted on the diverging arm IIb adjacent the end thereof and the contact I0 is mounted on the diverging arm IIc adjacent the end thereof. A piece of resilient metal I2 is secured to the other side of the insulating block 8 and engages the arms IIb and Ilc of the strip II. One end of the piece I2 and the contact 9 are secured to the arm llb by a rivet I3. Likewise, the other end of the piece I2 and the contact III are secured to the arm I I0 by a rivet I4. The metal strip I2, when assembled, is sprung so that when in the position shown in Fig. 3, it presses the arms IIb and He outwardly. The yoke Ii, in which the electromagnet coil 4 is mounted, is pivotally secured to the arms of a U-shaped bracket I5 that is mounted in the base of insulating material 3. The pivotal connection between the arms of the bracket I5 and the yoke 6 is adjacent the end of the yoke and the electrical connections to the electromagnet are at about the center of rotation of the electromagnet about its pivotal connection to the bracket I5.

Intermediate the end of the coil 4 and the end of the extended portion 5a of the core, there is mounted a C-shaped permanent magnet of an 40 aluminum-nickel-cobalt alloy IS. The C-shaped magnet is mounted on the base 3 and firmly secured thereto by a brass bracket II. The C- shaped magnet is so positioned that the extended portion 5a of the core of the electromagnet extends between the pole faces of the permanent magnet and in the air gap thereof. Mounted on the side of the permanent magnet I6 there is a keeper I111. The permanent magnet is an oversized magnet, that is, it is larger than necessary for performing its function. The keeper IIa. is rigidly secured to the permanent magnet and shunts or diverts a portion of thepermanent magnetflux that would otherwise have to pass the air gap between the pole faces of the permanent magnet. This arrangement insures a long, useful life for the permanent magnet.

In the arrangement so far described, the electromagnet together with its core, the extended portion a of the core, and the insulating block 3 carrying the contacts 9 and I9, is free to move about its pivotal connection with the bracket I9.

The amount of movement of the electromagnet is such that the extended portion 5a of the core may engage one or the other of the pole faces of the permanent magnet. The core of the electromagnet is of course of soft iron and it is attracted by the pole faces of the permanent magnet, depending upon the polarity of the electromanent magnet until the electromagnet has built up sufficient magnetomotive force at which time the core snaps over to the other face of the permanent magnet with a very positive. and quick movement. This is of importance, as will be hereinfter appreciated, for making and breaking electrical contacts through the contacts. 9 and I9 that are carried by the core of the electromagnet. In the arrangement shown, the contacts 9 and I9 on the electromagnet cooperate with fixed contacts I9 and I9 respectively. The contact I9 is mounted upon one arm of a V-shaped contact holder 29, the other arm of which is secured to the base 3 of insulating material. The contact I9 is similarly secured to one armof a V-shaped contact holder 2|, the other arm of which is also secured to the base of insulating material 3. The contact holders 29 and 2| are also of strip material and resilient though fairly rigid. It will be noticed that the faces of the contacts'9 and I9 are contained in diverging planes as are also the faces of the contacts I8 and I9. The contacts I9 and I9 are, as shown in Fig. 3, positioned so as to be engaged by the contacts 9 and I9 when the polarity of the electr'omagnet is such that the core is attracted by the lower face of the permanent magnet and repelled by the upper face of the permanent magnet. When the polarity of the electromagnet is changed so that the core of the electromagnet moves from the position shown in Fig. 3 to the position in which it engages the lower face of the permanent magnet, the contacts 9 and I9 are brought down into engagement with the contacts I9 and I9 respectively. The angular arrangement of the contacts provides a wiping action on the making and breaking of contact and the resilient material together with the spring element I2 provides a construction that makes the most of the pressure set up by the pole of the permanent magnet and effects a pressure contact between the contacts 9 and I9, and I9 and I9. The quick action of the relay in making and breaking the contacts, as explained above, minimizes arcing between the contacts.

The contact holder I9 is part of a conducting strip of metal I9a which has secured to one end a solderless connector 22. Similarly, the contact holder 2I is part of a strip of conducting metal in: which has secured on one end a solderless connector 23. The solderless connectors are providedI for connecting wires to the contacts I9 and 9.

Within the cabinet there is, in addition to the relay above described, a choke coil 24 that is mounted in the base '3 adjacent the relay, as shown in Fig. 1-. A pair of

fuse clips

25 and 29 are mounted on the base 3 in line with the choke coil and on one side of the conducting strip Ila. A similar pair of fuse clips 21v and 23 is mounted on the base 3 at one side of the conducting strip 10 2Ia, the conducting strips Ila and 2la being substantially one .on each side of the longitudinal'center of the base 3. The fuse clip'29 is provided with a solderless connector 29 and the fuse clip 23 is provided with a solderless conncctor 39. The conducting strips, Ila and 2la each have a fuse clip secured thereto, the conducting strip I921 having fuse clip 3| secured thereto, and the conducting strip 2Ia having fuse clip 32 secured thereto. The fuse clips 3| and 32 form a pair and are adapted to receive a fuse.

These fuse clips are provided so that in the event there is any difficulty with the relay mechanism a fuse inserted in the fuse clip 3| and 32 bridges the gap between the conducting strips Ila and 2 la and in effect form a connection between these two in the same manner as the contacts 9 and I9 which are electrically connected together and which when engaging the contacts I3 and I9 electrically connect these contacts together.

The manner in which the several parts described above are electrically interconnected is illustrated in the diagram in Fig. 5 which also illustrates the manner in which the relay is interconnected in a street lighting system. From Fig.

5 it will be seen that the fuse clips 23 and 29 receive a fuse 33 and thus there is a connection between the connector 29 and the fuse clip 25. The fuse clip 25 is connected by a conductor 34 to one-side of the choke coil 24. of the choke coil 24 is connected by a conductor 35 to one side of the electromagnet coil 4. The other side of the coil 4 of the electromagnet is connected by a conductor 39 to the connector 360 that is mounted on the base 3 between the connectors 29 and 39. The connector 23 is, -in a normal operation of the relay device, connected to the fuse 'clip 21. Thus, the contact I 9 is connected to the connector 39 when a fuse is inserted in the fuse clips 21 and 29. As previously stated, the conducting strip I8a connects the contact I9 and the connector 23.

In the diagram shown in Fig. 5, the source of current for the street lighting system is indicated bya generator 31. current generator and is generally a three-wire circuit. For the purpose of simplifying the diagram, however, there is just shown two line wires, the neutral grounded wire 39, and one of the line wires 39. The street lamp for which the relay is 0 provided is indicated at 49. I A battery, usually a storage battery 4|, provides the source of current for operating the relay. This battery is connected to a double-pole, double-throw switch 42.

One side of the switch is connected by a conductor 43 to the connector 29. The other side of the switch 42 is connected to the neutral wire 39 of the street lighting system. The connector I 36a of the relay is connected by a conductor 44 to the neutral wire 38. One side of the lamp 49 is connected by a conductor 45 to the line wire 39. and the other side of the lamp 49 is connected by a conductor 46 to the connector 22. The connector 39 is connected to the neutral wire 39.

With the arrangement shown, it will be seen The other side 40 This is an alternating 55 that when the switch 42 is in one position, so as to engage the contacts at the right in Fig. 5, there will be a circuit from one side of the battery through the switch 42, the conductor 43,

fuse I3, choke coil 24, coil of the electromagnet 4, conductor 36, conductor 44, neutral wire 38, back to switch 42 and thence to the other side of the battery. When so connected, the relay 4 will be energized and have a certain polarity. The extended core 5a of the relay will be drawn by one of the poles of the electromagnet and repelled by the other. If the switch 42 is now thrown so that the contacts at the left of Fig. 5 are engaged, the same circuit will be closed, but the polarity will be opposite to that when the switch engages the contacts at the left in Fig. 5. The electromagnet will have an opposite polarity and the core 50 will be repelled by the pole of the permanent magnet which it then engages and attracted by the other pole of the permanent magnet. Thus the electromagnet is operated to open and close a circuit between the contacts 9, l0, and l8, l9. When the electromagnet is operated so that the contacts 9 and ill respectively engage the contacts l8 and 19, there is a circuit through the lamp 40 as follows: line wire 39, conductor 45, lamp 40, connector 23, contact I8, contact 9, contact I0, contact l9, fuse clips 21 and 28, and the conductor 41 connecting connector 30 with the neutral wire 38. When the electromagnet is polarized so as to separate the contacts 9 and HI and I8 and I9, this circuit is broken. It should be noted that it is only necessary to throw the switch 42 to change the polarity of the electromagnet to eifect operation of the magnet. After the magnet has been operated it is not necessary to maintain the switch 42 closed as the permanent magnet will hold the electromagnet in the position to which it was moved.

It will be noted that the direct current circuit for operating the relay is interconnected with the alternating current circuit of the street lighting system and the choke coil 24 is utilized to prevent the passage of alternating current to the electromagnet of the relay. In the event of a leak of alternating current through the choke coil there would normally be built up in the electromagnet a high voltage that might rupture the insulation. To guard the electromagnet against this condition there is provided an extension 48 of the bracket I! to which the permanent magnet is secured. This extension of the bracket l1 extends across the end of the electromagnet and it is provided with a slot through which the core of the magnet extends. The extension 48 acts in the capacity of a short circuited secondary for the electromagnet 4 and in consequence if the alternating current leaks through the choke coil, 2. high voltage will not be built up in the electromagnet.

From the foregoing description of the relay disclosed in the drawings, it will be seen that there is provided an efllcient, eifective relay construction that is simple in construction and that has few parts that are likely to get out of order and that will function over a long period of time.

It is obvious that various changes may be made by those skilled in the art in the details of the embodiment of the invention disclosed in the drawings and described above within the principle and scope of the invention as expressed in the appended claims.

We claim:

1. A relay of the type described comprising a base, a bracket mounted on the base, a U-shaped element pivotally mounted in the bracket, an electromagnet mounted in the U-shaped element, the electromagnet having a core extending axially from one end thereof, a pair of electrical contacts resiliently mounted on the extended core adjacent the end thereof, a pair of stationary contacts mounted on the base and positioned to be engaged by the contacts carried by the core of the electromagnet, a permanent magnet embracing the extended core of the electromagnet and positioned so that the extended core lies in the air gap thereof, and a keeper on the permanent magnet.

2. A relay of the type described comprising a base, a bracket mounted on the base, a U-shaped element pivotally mounted in the bracket, an electromagnet mounted in the U-shaped element, the electromagnet having a core extend ing axially from one end thereof, a pair of electrical contacts resiliently mounted on the extended core adjacent the end thereof, the contacting surfaces of the contacts converging, a pair of stationary contacts having converging contacting surfaces mounted on the base and positioned to be engaged by the contacts mounted on the extended core of the electromagnet, a C- shaped permanent magnet mounted on the base transversely of the axis of the extended core of the electromagnet and positioned so that the extended core of the electromagnet is between the pole faces thereof, and a keeper on the permanent magnet.

3. In a relay of the type described, a relay core, a bar of insulating material secured on the end of the core, a strip of spring metal secured on one side of the bar of insulating material including a central section secured to the bar of insulating material and an angularly disposed section extending from each end of the central section, another strip of spring metal extending between and secured to the free ends of the angularly disposed sections of the first mentioned strip and contacts, one secured on each of the angularly disposed sections of the first mentioned strip.

4. A relay of the type described comprising in combination a pivotally mounted electromagnet having a core extending therefrom and carrying electrical contacts, stationary contacts positioned to co-operate with the contacts on the core of the electromagnet, an oversized C-shaped permanent magnet extending transversely to the core of the electromagnet and embracing the core of the electromagnet, the permanent magnet being arranged so that the core of the electromagnet contacts only a fraction of the face of the permanent magnet, and a keeper on the permanent magnet.

ALBERT B. RYPINSKI. CHARLES A. BAY.