US2875293A - Relay - Google Patents

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Publication number
US2875293A
US2875293A US467296A US46729654A US2875293A US 2875293 A US2875293 A US 2875293A US 467296 A US467296 A US 467296A US 46729654 A US46729654 A US 46729654A US 2875293 A US2875293 A US 2875293A
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Prior art keywords
shaft
contacts
housing
relay
armature
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Expired - Lifetime
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US467296A
Inventor
Richard L Adams
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Leach Corp
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Leach Corp
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H50/00Details of electromagnetic relays
    • H01H50/16Magnetic circuit arrangements
    • H01H50/18Movable parts of magnetic circuits, e.g. armature
    • H01H50/30Mechanical arrangements for preventing or damping vibration or shock, e.g. by balancing of armature

Definitions

  • a feature of this invention vis the provision of a relay which can be used under circumstances of high ac celeration without any improper operations.
  • Another feature of this invention is the provision of an improved relay which may be operated under conditions of vibration and still operate properly.
  • Still another feature of the invention' is the provision ofanovel relay which is not adversely affected by conditions of high temperature. J
  • a further feature of the present invention is the provision of a novel and useful relay which is glight and small andyet can-perform multiple functions of heavier and'bulkier relays.- 7
  • An end-play takethe magnetic actuator or motor.
  • This includes a pair of parallel solenoid coils --which 'are'mounted spaced apart on abase plate and have their cores extending therefrom axially and parallel to one another. Between the cores is a rotatably mounted shaft. Attached to the shaft to rotate therewith is an armaure which consists of metal laminations which extend to the cores. The shaft is biased by means of a spring to rotate the armature away from the cores. Means are provided to limit such rotation.
  • the shaft extends into the secn i sembly whi h i alled th contact assembly.
  • a plurality of conductors are mounted to be spaced from theshaft to be rotatable therewith and also to be insulated therefrom.
  • a housing surroundsthis portion of the shaft and the conductors. Inside this housing are mounted stationary contacts. These are in adjacent spaced pairs, each pair being associated with one of the conductors carried by the shaft.
  • Figure 1 is a view in section of an embodiment of the invention
  • Figure 2 is a view along the plane 2-2 of Figure 1 which shows a bottom view of an embodiment of the invention
  • Figure 3 shows the contact and conductor arrangement of the embodiment of the invention
  • Figure 4 is a view along the plane 4-4 of Figure 1. It shows the armature and core layout of the motor assembly
  • Figure 5 is a view along the plane 55 of Figure l. Itsh ows the layout of the contact assembly.
  • Figure ,6 is a view along the section 66 of Figure 1. It shows the arrangement for spring biasing the motor shaft.
  • FIG. 1 of the drawings there may be seen insection an embodiment of the invention.
  • This includes a base plate 10, which has mounted thereupon two coils 12, 1-2. Respectively extending therefrom are two cores 14, 14.
  • a top plate 16 extends betweenthe two cores and is fastened thereto'by means of two screws 18, 13'.
  • a shaft 20 is rotatably supported between the top and bottom plate 16 and 10 by two bearings 22. These may better be seen in Figure 6.
  • the top plate may be fabricated of stainless steel and carries an armature backstop 24.
  • An armature 26, consisting of a number of metal laminations which are welded together, is staked to the shaft 2ft to be rotatable therewith. The armature may be better seen in Figure 4.
  • a spring 28, which is shown in Figure 6, is used to bias the shaft 20 so that it rotates the armature away from the cores 14 14'.
  • the spring 28 has one end mechanically coupled to a pin 30 which is staked to the shaft. The other end extends around one post 32 of a pair of posts .32, 32. These posts serve as additional supports and spacers between the upper and lower base plates.
  • the housing 34 for the stationary contact assembly is attached to the upper base plate by means of two-screws36, 316". Between the two coils and the spacing wherein the armature operates, there is a sheet of 'an insulating laminate 38.
  • This sheet serves as the llv W hr ⁇ 10 is inserted between the armature and the lP i fljp he torsion spring biases the shaft so that when the series-connected solenoid coils are not excited the armature is maintained rotated against the backstop and away from the cores. When the coils are excited, the armature is attracted to the cores and rotates, rotating therewith the shaft.
  • the housing 34 for the stationary contacts completely encloses the solenoid cores and armature of the motor.
  • the movable contacts for the contact assembly are carried bythe shft 20, which extends into the upper portion of the contact housing.
  • the contact housing 34 surrounds the movable contact assembly.
  • This movable contact assembly may include one or more conductors 50, which'are -insulatingly supported from the shaft as well as in a manner to be rotated therewithl
  • the support for the conductors consists of two identical members 52, 52. These are made of plastic and each has an extrusion and recess 54, which, when the two parts are placed together, act to lock the two parts, preventing any-turning relative to each other.
  • Recesses 56 are provided in the members 52, 52.
  • Each conductor 50 has an associated spring 58. Both of these have rectangular lugs 60, which enable them to be fitted into the recesses in the supporting member whereby they are retained in position.
  • the supporting members 52, 52' are clamped to the shaft 20 by means of two D-Washers 62, 62' and a nut 64, which is tightened to the threaded end of the shaft.
  • the shaft has the portion, over which the members 52 fit, properly notched to cooperate with the two D-washers 62, 62.
  • the housing 34 has mounted therein pairs of stationary contacts 70, 70'. These pairs of contacts are spaced apart sufficiently so that they do not interfere with or contact each other and yet may be bridged by the conductor 50 when it is applied across the pair of contacts by operation of the relay motor. Connections external to the housing are made with these contacts by means 3 of the threaded bolts 72, 72.
  • the housing 34 may be made of a molded glass reinforced polyester plastic which has holes properly placed in the sides thereof for mounting the stationary contacts. In order to prevent the larger contacts from being turned by operation of the relay, the corners 78 thereof which are next to the housing are coined. As is well known, this doubly insures anchoring in the material of the housing by forcing some of the metal in the coined portion to more intimately engage with the material in the housing.
  • the movable contact assembly on the motor shaft is properly set manually and the overtravel is compensated by rotating the movable conductors in relation to the motor shaft.
  • the fastening nut 64 is then tightened and the assembly may be drilled and a drive pin 90 set to fix the position.
  • the armature is drawn toward the cores, thus rotating the shaft and moving the conductors to bridge the associated pairs of contacts.
  • the spring 28 snaps the armature back to its inactive position, thus breaking open the circuits at the various pairs of contacts.
  • FIG. 5 By way of illustration of an embodiment of the invention which has been constructed, four conductors and four pairs of associated contacts are shown in Figure 5.
  • the contacts have different current-carrying ability, the heavier ones, for example, being able to carry 150 amperes, the lighter ones carrying 25 amperes.
  • the number of contacts which are made or broken by operation of the relay may be increased or decreased in manner well known to the art.
  • the top of the housing for the contacts is covered so that the complete assembly is dust free, and, in view of the virtues of the housing, substantially thermally unaffected. Due to the fact that the armature shaft and moving contact assembly are balanced, directly coupled andheld by two closely fitting bearings, the relay is highly resistant to vibration, shock and acceleration.
  • the contacts are highly resistant to welding, since the armature is provided with a high mass and delivers a hammer blow directly to the contacts. In view of the motor construction, the armature has a decided mechanical advantage over the contacts, resulting in a fairly high contact pressure.
  • a contact assembly for a relay of the type having a shaft rotatably driven through a limited are by a motor, said assembly comprising a movable contact assembly ineluding a plurality of conductors, means to insulatingly support said conductors to extend parallel to said shaft and to be rotatable therewith, said means including a collar which fits over said shaft and a plurality of arms extending radially from said collar, said collar and arms a'sraaea being made of insulating material, a recess in each of said arms, a plurality of elongated spring members, a different one of said plurality of conductors and elongated spring members being mounted into a different one of said recesses with an elongated spring backing a con ductor, and means to fasten said collar to said shaft, and a stationary contact assembly including a different pair of contacts associated with each of said plurality of conductors, and means to support said pairs of con tacts spaced around said shaft to be bridged
  • a contact assembly for a relay of the type having a shaft rotatably driven through a limited are by a motor said contact assembly comprising a collar attached to said shaft, said collar having a plurality of arms extending radially therefrom, said collar and arms being made of an insulating material, a plurality of plate-like bridge contacts each of which is supported at the extremity of a different one of said radially extending arms to extend parallel to said shaft, a flat spring for each one of said bridge contacts each of said springs being mounted for reinforcing an associated bridge contact, a hollow housing made of an insulating material, said hollow housing surrounding said movable contact assembly, a plurality of pairs of contacts, means to mount each of said'pairs of contacts around the inside of said housing to be bridged by a different one of said bridge contacts when said shaft is rotated'by said motor, and means atfording connection to each of said pairs of contacts through said housing walls.
  • a contact assembly as recited in Claim 4 wherein certain ones of said pairs of contacts have a shouldered portion to secure their anchorage to the inner walls of said housing.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Electromagnets (AREA)
  • Switch Cases, Indication, And Locking (AREA)
  • Motor Or Generator Frames (AREA)

Description

Feb. 24, 1959 Q. L. ADAMS RELAY Filed Nov. 8, 1954 2 Sheets-Sheet l 78 54, /CA/fl'fl 4. 90M5 INVENTOR.
- A79. 5. w m 78 70 Y Feb. 24, 1959 R. L. ADAMS 2,875,293
RELAY Filed NOV. 8, 1954 2 Sheets-Sheet 2 INVENTOR.
United S s P ent??? :RELAY R c ard L- Adams, Los Ange es, Califl, assign r o ea h- Corporation, Los Angeles, Delaware Cal f, o p ra on o This invention relates to electromagnetic relays and, more particularly, to improvements therein. I I
A feature of this inventionvis the provision of a relay which can be used under circumstances of high ac celeration without any improper operations.
Another feature of this invention is the provision of an improved relay which may be operated under conditions of vibration and still operate properly.
Still another feature of the invention'is the provision ofanovel relay which is not adversely affected by conditions of high temperature. J
' A further feature of the present invention is the provision of a novel and useful relay which is glight and small andyet can-perform multiple functions of heavier and'bulkier relays.- 7
These and other features of'the invention are achieved in an embodiment of this invention consisting of are l y having o ain assemblies. The first of these s. bottom of the armature enclosure. An end-play takethe magnetic actuator or motor. This includes a pair of parallel solenoid coils --which 'are'mounted spaced apart on abase plate and have their cores extending therefrom axially and parallel to one another. Between the cores is a rotatably mounted shaft. Attached to the shaft to rotate therewith is an armaure which consists of metal laminations which extend to the cores. The shaft is biased by means of a spring to rotate the armature away from the cores. Means are provided to limit such rotation. The shaft extends into the secn i sembly whi h i alled th contact assembly. A plurality of conductors are mounted to be spaced from theshaft to be rotatable therewith and also to be insulated therefrom. A housing surroundsthis portion of the shaft and the conductors. Inside this housing are mounted stationary contacts. These are in adjacent spaced pairs, each pair being associated with one of the conductors carried by the shaft. When the solenoids are excited, the armature rotates and themtating shaft moves the conductors to bridge their associated stationary contact pairs. When the excitation is removed from the solenoid, the spring bias returns the shaft to its nonoperative position.
The novel features that are considered characteristic of this invention are set forth with particularity in the appended claims. The invention itself, both as to its organization and method of operation, as well as additional objects and advantages thereof, will best be understood from the following description when read in connection with the accompanying drawings, in which:
Figure 1 is a view in section of an embodiment of the invention;
Figure 2 is a view along the plane 2-2 of Figure 1 which shows a bottom view of an embodiment of the invention;
Figure 3 shows the contact and conductor arrangement of the embodiment of the invention;
Figure 4 is a view along the plane 4-4 of Figure 1. It shows the armature and core layout of the motor assembly;
2,875,293 Patented Feb. 24, was
Figure 5 is a view along the plane 55 of Figure l. Itsh ows the layout of the contact assembly; and
Figure ,6 is a view along the section 66 of Figure 1. It shows the arrangement for spring biasing the motor shaft.
Referring now to Figure 1 of the drawings, there may be seen insection an embodiment of the invention. This includes a base plate 10, which has mounted thereupon two coils 12, 1-2. Respectively extending therefrom are two cores 14, 14. A top plate 16 extends betweenthe two cores and is fastened thereto'by means of two screws 18, 13'. A shaft 20 is rotatably supported between the top and bottom plate 16 and 10 by two bearings 22. These may better be seen in Figure 6. The top plate may be fabricated of stainless steel and carries an armature backstop 24. An armature 26, consisting of a number of metal laminations which are welded together, is staked to the shaft 2ft to be rotatable therewith. The armature may be better seen in Figure 4. A spring 28, which is shown in Figure 6, is used to bias the shaft 20 so that it rotates the armature away from the cores 14 14'. The spring 28 has one end mechanically coupled to a pin 30 which is staked to the shaft. The other end extends around one post 32 of a pair of posts .32, 32. These posts serve as additional supports and spacers between the upper and lower base plates. The housing 34 for the stationary contact assembly is attached to the upper base plate by means of two-screws36, 316". Between the two coils and the spacing wherein the armature operates, there is a sheet of 'an insulating laminate 38. This sheet serves as the llv W hr {10 is inserted between the armature and the lP i fljp he torsion spring biases the shaft so that when the series-connected solenoid coils are not excited the armature is maintained rotated against the backstop and away from the cores. When the coils are excited, the armature is attracted to the cores and rotates, rotating therewith the shaft. Thus far there has been described the motor assembly of the relay. The housing 34 for the stationary contacts completely encloses the solenoid cores and armature of the motor.
The movable contacts for the contact assembly are carried bythe shft 20, which extends into the upper portion of the contact housing.
The contact housing 34 surrounds the movable contact assembly. This movable contact assembly may include one or more conductors 50, which'are -insulatingly supported from the shaft as well as in a manner to be rotated therewithl The support for the conductors consists of two identical members 52, 52. These are made of plastic and each has an extrusion and recess 54, which, when the two parts are placed together, act to lock the two parts, preventing any-turning relative to each other. Recesses 56 are provided in the members 52, 52. Each conductor 50 has an associated spring 58. Both of these have rectangular lugs 60, which enable them to be fitted into the recesses in the supporting member whereby they are retained in position. The supporting members 52, 52' are clamped to the shaft 20 by means of two D-Washers 62, 62' and a nut 64, which is tightened to the threaded end of the shaft. The shaft has the portion, over which the members 52 fit, properly notched to cooperate with the two D- washers 62, 62.
The housing 34 has mounted therein pairs of stationary contacts 70, 70'. These pairs of contacts are spaced apart sufficiently so that they do not interfere with or contact each other and yet may be bridged by the conductor 50 when it is applied across the pair of contacts by operation of the relay motor. Connections external to the housing are made with these contacts by means 3 of the threaded bolts 72, 72. The housing 34 may be made of a molded glass reinforced polyester plastic which has holes properly placed in the sides thereof for mounting the stationary contacts. In order to prevent the larger contacts from being turned by operation of the relay, the corners 78 thereof which are next to the housing are coined. As is well known, this doubly insures anchoring in the material of the housing by forcing some of the metal in the coined portion to more intimately engage with the material in the housing.
Upon assembly, the movable contact assembly on the motor shaft is properly set manually and the overtravel is compensated by rotating the movable conductors in relation to the motor shaft. The fastening nut 64 is then tightened and the assembly may be drilled and a drive pin 90 set to fix the position. Upon excitation of the series-connected solenoids, the armature is drawn toward the cores, thus rotating the shaft and moving the conductors to bridge the associated pairs of contacts. When excitation is removed from the coils, the spring 28 snaps the armature back to its inactive position, thus breaking open the circuits at the various pairs of contacts.
By way of illustration of an embodiment of the invention which has been constructed, four conductors and four pairs of associated contacts are shown in Figure 5. The contacts have different current-carrying ability, the heavier ones, for example, being able to carry 150 amperes, the lighter ones carrying 25 amperes. Of course, the number of contacts which are made or broken by operation of the relay may be increased or decreased in manner well known to the art. The top of the housing for the contacts is covered so that the complete assembly is dust free, and, in view of the virtues of the housing, substantially thermally unaffected. Due to the fact that the armature shaft and moving contact assembly are balanced, directly coupled andheld by two closely fitting bearings, the relay is highly resistant to vibration, shock and acceleration. Furthermore, the contacts are highly resistant to welding, since the armature is provided with a high mass and delivers a hammer blow directly to the contacts. In view of the motor construction, the armature has a decided mechanical advantage over the contacts, resulting in a fairly high contact pressure.
There has, accordingly, been described herein a novel and useful relay which is substantially unaffected by vibration, acceleration, and shock, as well as temperature, due to its unique construction. Further, the coining of the contacts prevents their being turned by operation of the relay.
. I claim:
1. A contact assembly for a relay of the type having a shaft rotatably driven through a limited are by a motor, said assembly comprising a movable contact assembly ineluding a plurality of conductors, means to insulatingly support said conductors to extend parallel to said shaft and to be rotatable therewith, said means including a collar which fits over said shaft and a plurality of arms extending radially from said collar, said collar and arms a'sraaea being made of insulating material, a recess in each of said arms, a plurality of elongated spring members, a different one of said plurality of conductors and elongated spring members being mounted into a different one of said recesses with an elongated spring backing a con ductor, and means to fasten said collar to said shaft, and a stationary contact assembly including a different pair of contacts associated with each of said plurality of conductors, and means to support said pairs of con tacts spaced around said shaft to be bridged by the ones of the conductors associated therewith when said motor is excited.
2. A contact assembly as recited in claim 1, wherein said stationary contact assembly includes a housing made of insulating material surrounding said movable contact assembly, each of said pairs of contacts being mounted about the inner wall of said housing to be bridged by said one of said conductors associated therewith when said motor is excited.
3. A relay as recited in claim 2, wherein desired ones of said pairs of contacts have a shouldered portion to secure their anchorage to the inner wall of said housing.
4. A contact assembly for a relay of the type having a shaft rotatably driven through a limited are by a motor said contact assembly comprising a collar attached to said shaft, said collar having a plurality of arms extending radially therefrom, said collar and arms being made of an insulating material, a plurality of plate-like bridge contacts each of which is supported at the extremity of a different one of said radially extending arms to extend parallel to said shaft, a flat spring for each one of said bridge contacts each of said springs being mounted for reinforcing an associated bridge contact, a hollow housing made of an insulating material, said hollow housing surrounding said movable contact assembly, a plurality of pairs of contacts, means to mount each of said'pairs of contacts around the inside of said housing to be bridged by a different one of said bridge contacts when said shaft is rotated'by said motor, and means atfording connection to each of said pairs of contacts through said housing walls.
5. A contact assembly as recited in Claim 4, wherein certain ones of said pairs of contacts have a shouldered portion to secure their anchorage to the inner walls of said housing.
References Cited in the file of this patent UNITED STATES PATENTS
US467296A 1954-11-08 1954-11-08 Relay Expired - Lifetime US2875293A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3059076A (en) * 1960-04-05 1962-10-16 Allied Control Co Electromagnetic switch
US3109903A (en) * 1960-08-04 1963-11-05 Automatic Elect Lab Electromagnetic miniature relays
US3192340A (en) * 1963-03-15 1965-06-29 Texas Instruments Inc Center pivoted armature electro-magnetic switching mechanism
US3194918A (en) * 1963-10-04 1965-07-13 Anthony J Muscante Contactor for electric torpedoes

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1763003A (en) * 1929-05-06 1930-06-10 Bell Telephone Labor Inc Electromagnetic device
US2203297A (en) * 1937-05-04 1940-06-04 Sundstrand Machine Tool Co Control mechanism
US2393535A (en) * 1943-07-31 1946-01-22 Allied Control Co Electromagnetic relay
US2532305A (en) * 1949-08-17 1950-12-05 Cutler Hammer Inc Electric switch
US2590996A (en) * 1947-11-21 1952-04-01 Bell Telephone Labor Inc Relay
US2604792A (en) * 1947-04-19 1952-07-29 Max L Jeffrey Snap action mechanism
US2647974A (en) * 1950-12-01 1953-08-04 Arrow Hart & Hegeman Electric Electric switch contact assembly
US2767280A (en) * 1952-04-29 1956-10-16 North Electric Co Relay structure

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1763003A (en) * 1929-05-06 1930-06-10 Bell Telephone Labor Inc Electromagnetic device
US2203297A (en) * 1937-05-04 1940-06-04 Sundstrand Machine Tool Co Control mechanism
US2393535A (en) * 1943-07-31 1946-01-22 Allied Control Co Electromagnetic relay
US2604792A (en) * 1947-04-19 1952-07-29 Max L Jeffrey Snap action mechanism
US2590996A (en) * 1947-11-21 1952-04-01 Bell Telephone Labor Inc Relay
US2532305A (en) * 1949-08-17 1950-12-05 Cutler Hammer Inc Electric switch
US2647974A (en) * 1950-12-01 1953-08-04 Arrow Hart & Hegeman Electric Electric switch contact assembly
US2767280A (en) * 1952-04-29 1956-10-16 North Electric Co Relay structure

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3059076A (en) * 1960-04-05 1962-10-16 Allied Control Co Electromagnetic switch
US3109903A (en) * 1960-08-04 1963-11-05 Automatic Elect Lab Electromagnetic miniature relays
US3192340A (en) * 1963-03-15 1965-06-29 Texas Instruments Inc Center pivoted armature electro-magnetic switching mechanism
US3194918A (en) * 1963-10-04 1965-07-13 Anthony J Muscante Contactor for electric torpedoes

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