US2323910A - Magnetic switch - Google Patents

Magnetic switch Download PDF

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US2323910A
US2323910A US435375A US43537542A US2323910A US 2323910 A US2323910 A US 2323910A US 435375 A US435375 A US 435375A US 43537542 A US43537542 A US 43537542A US 2323910 A US2323910 A US 2323910A
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armature
magnet
contact
poles
movable
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US435375A
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Hubbell Harvey
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H36/00Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding

Definitions

  • This invention relates to electric switches and particularly a magnetically operated switch, and has for an object to provide a construction in which the operating effort is reduced to a minimum.
  • a particular object is to provide a construction of switch using a magnetic operating means, in which as the magnetic operating means is moved to and from a position to shift the movable armature the magnetic or flux circuit is shifted between the movable armature and a stationary armature, so that the pull of the movable armature on the magnet as the magnet moves away from it is reduced to a minimum, thus reducing to a minimum the resistance to shifting of the magnet and reducing the effort required for this operation.
  • Fig. 1 is a longitudinal section through one form of the device showing the switch in closed position, certain elements being shown in elevation;
  • Fig. 2 is a section substantially on the line 2-2 of Fig. 1;
  • Fig. 3 is a transverse section substantially on the line 3-3 of Fig. 1;
  • Fig. 4 is a partial section and partial elevation of the main elements of the switch similar to Fig. 1 but showing the movable parts with the switch in the open position;
  • Fig. 5 is a section showing a modified construction with the switch in closed position
  • Fig. 6 is a transverse section substantially on the line 6-6 of Fig. 5, and
  • Fig. 7 is a similar section but showing the switch in the open or off position.
  • the switch illustrated comprises a base ID of insulating material on which is mounted the movable switch element I I, in this case a flat spring, mounted on a suitable support, as a metal conducting post l2 mounted in the base [0, this spring element being secured thereto by any suitable means, such as a screw l3.
  • the post extends through the base In and connects with a strap I4 on which is a binding screw l5 for connection of a lead wire l8.
  • the member ll carries a contact element ii and an armature it which in this case is a fiat strip of soft iron,
  • a stationary contact it to cooperate with the contact ill is mounted on a bracket it secured to the base iii by any suitable means, such as a rivet 2i which also mounts on the base a strap 22 carrying a binding screw it for connection of the lead 26.
  • the contact 9 is adjustable in the bracket, and in this case comprises a screw as shown.
  • a second support or bracket it is mounted on the base by any suitable means such as the screws 26, and carries a bearing 2? for a short shaft 28 mounted on the lower end of which is a substantially U-shaped magnet it having the spaced pole pieces tilt located slightly above the armature it so that there is a clearance space between them.
  • This'shaft it may be operated by any suitable means to turn or oscillate it, as for example by a handle 3i. By turning this shaft the magnet is turned to carry the poles 3G to and from a position over the armature iii and a position adjacent thereto, as shown in the full and dotted lines Figs. 1, 2 and 3, the dotted lines of Fig. 2 and the full lines of Fig. 4 showing the magnet in position to release the armature l8 and permit the resiliency of the spring H to shift the contact ll away from the contact 58, as shown in Fig. 4, to break or open the circuit.
  • armature i8 Laterally to one side of the armature i8 is a stationary armature in this case comprising the two arc-shaped elements one located on each of opposite sides of the armature it, so that when the magnet 29 is rotated to carry the poles from the armature it they will pass over the stationary armature members 33.
  • the members 33 may be secured to the base by any suitable means such for example as lugs 33a passing through the base and bent over on the under side. There is also a slight clearance between the poles 3i! and the armature elements 33, about the same as that between these poles and the armature it, so that the wmatures will not freeze to the magnet and there will be no friction between them.
  • the parts may be enclosed by a suitable cover or casing C. 1
  • FIG. 5 to '7 Another arrangement is shown by way of example in Figs. 5 to '7.
  • the spring contact is the same as in Figs. 1 to d but the operating magnet 34 corresponding to the magnet 253 is mounted differently.
  • it is mounted on a supportilt pivoted on a short shaft or stud 3h mounted in a supporting bracket 32 secured to the base it by any suitable means, such as a rivet 3.
  • the support 35 includes an operating means such as a handle 39.
  • armature members Qt may be secured to the base by any suitable means such for example as the lugs 33 extending through and bent over on the underside of the base.
  • the magnetic or flux circuit is transferred from the armature it to the corroesponding armature member 3 so that it is now through this armature memher and the magnet, which releases the attraction of the magnet on the armature i8 permit ting the spring ii to shift the contact it away from the contact 99 to open the circuit.
  • the magnetic or flux circuit is transferred from the movable armature to the stationary armature there is no pull of the movable armature on the magnet to resist its swinging movement, so that the only resistance to movement of the magnet is that within the pivotal bearing 36 or any other operating means that may be employed.
  • An electric switch comprising a movable contact, an armature connected therewith, a magnet mounted for movement to and from a position over the armature to shift and release it to operate the contact, and a stationary armature at one side of the first armature over which the magnet moves as it is shifted from the first armature, both armatures being always spaced from the magnet.
  • a movable contact In an electric switch, a movable contact, a movable armature for shifting the contact, a magnet movable to and from aposition adjacent the armature to attract and release it, and a second armature arranged so that as the magnet moves from the first armature it approaches the second to transfer the magnetic field from the first to the second armature, both armatures being always spaced from the magnet.
  • An electric switch comprising a spring support, a movable contact carried by said support, an armature on the support, a magnet mounted for movement to a position adjacent the armature to attract it to shift the contact, and a sec-- ond armature adjacent the first and toward which the magnet moves as it leaves the first armature to transfer its flux to the second armature, both armatures being always spaced from the magnet.
  • An electric switch comprising a movable contact, an armature connected therewith for shifting it, a substantially U-shaped magnet they are shifted from the first armature, both armatures being always spaced from the magnet.
  • An electric switch comprising a spring contact support. an armature mounted on said support, a substantially U-shaped magnet movable to and from a position with its poles over the armature to shift the "armature and support against the action of the spring, and a second armature adjacent the first armature over which the poles move as they leave the first armature, both armatures being always spaced from the magnet.
  • An electric switch comprising a movable contact, an armature connected therewith, a substantially U-shaped magnet having spaced poles and mounted to turn about an axis extending longitudinally of the poles, said poles movable to a position closely over the armature during its turning movement to shift the armature, other armature means laterally of the first ar mature over which the poles move during other parts of their turning movement to release the first armature, both armatures being always spaced from the magnet, and means for turning the magnet,
  • An electric switch comprising a movable contact, an armature connected therewith, a magnet having spaced poles mounted to swing 1o laterally to and from a position over the armature to shift it, another armature at one side of the first armature over which the poles move as they leave the first armature to release it, both armatures being always spaced from the mag- 5 me, and means for shifting the magnet.
  • armature 20 means laterally of the first armature over which the magnet moves as it leaves the first armature to release it, both armatures being always spaced from the magnet, and means for shifting the magnet,

Landscapes

  • Rotary Switch, Piano Key Switch, And Lever Switch (AREA)

Description

July 13, 1943; UB LL 2,323,910
MAGNETIC SWITCH Filed March 19, 1942 2 Sheets-Sheet l v I D O 5 0 I '7 l/ Z6 /4 F' o 4 3; W Z4 I W July 13, 1943. 'H. HUBBELL 2,323,910
- MAGNETIC SWITCH Filed March 19, 1942 2 Sheets-Sheet 2 3 ".Wbi 1377.
Wan a,
IPaiented duty 13, W43
2,323,9iil
MAGNE'JTHC SWlITtJi-E Harvey Hnbbell, Long mill, Conn.
Application March lit, 1M2, Serial No. 135,375
(El. scre s?) 9 Claims.
This invention relates to electric switches and particularly a magnetically operated switch, and has for an object to provide a construction in which the operating effort is reduced to a minimum. A particular object is to provide a construction of switch using a magnetic operating means, in which as the magnetic operating means is moved to and from a position to shift the movable armature the magnetic or flux circuit is shifted between the movable armature and a stationary armature, so that the pull of the movable armature on the magnet as the magnet moves away from it is reduced to a minimum, thus reducing to a minimum the resistance to shifting of the magnet and reducing the effort required for this operation.
With the foregoing and other objects in view I have devised a construction two embodiments of which are shown by way of example in the accompanying drawings forming a part of this specification. It is, however, to be understood the invention is not limited to the specific constructions and arrangements shown but may employ various changes and modifications within the scope of the invention.
In these drawings:
Fig. 1 is a longitudinal section through one form of the device showing the switch in closed position, certain elements being shown in elevation;
Fig. 2 is a section substantially on the line 2-2 of Fig. 1;
Fig. 3 is a transverse section substantially on the line 3-3 of Fig. 1;
Fig. 4 is a partial section and partial elevation of the main elements of the switch similar to Fig. 1 but showing the movable parts with the switch in the open position;
Fig. 5 is a section showing a modified construction with the switch in closed position;
Fig. 6 is a transverse section substantially on the line 6-6 of Fig. 5, and
Fig. 7 is a similar section but showing the switch in the open or off position.
Referring first to Figs. 1 to 4, the switch illustrated comprises a base ID of insulating material on which is mounted the movable switch element I I, in this case a flat spring, mounted on a suitable support, as a metal conducting post l2 mounted in the base [0, this spring element being secured thereto by any suitable means, such as a screw l3. The post extends through the base In and connects with a strap I4 on which is a binding screw l5 for connection of a lead wire l8.
The member ll carries a contact element ii and an armature it which in this case is a fiat strip of soft iron, A stationary contact it to cooperate with the contact ill is mounted on a bracket it secured to the base iii by any suitable means, such as a rivet 2i which also mounts on the base a strap 22 carrying a binding screw it for connection of the lead 26. The contact 9 is adjustable in the bracket, and in this case comprises a screw as shown.
A second support or bracket it is mounted on the base by any suitable means such as the screws 26, and carries a bearing 2? for a short shaft 28 mounted on the lower end of which is a substantially U-shaped magnet it having the spaced pole pieces tilt located slightly above the armature it so that there is a clearance space between them. This'shaft it may be operated by any suitable means to turn or oscillate it, as for example by a handle 3i. By turning this shaft the magnet is turned to carry the poles 3G to and from a position over the armature iii and a position adjacent thereto, as shown in the full and dotted lines Figs. 1, 2 and 3, the dotted lines of Fig. 2 and the full lines of Fig. 4 showing the magnet in position to release the armature l8 and permit the resiliency of the spring H to shift the contact ll away from the contact 58, as shown in Fig. 4, to break or open the circuit.
Laterally to one side of the armature i8 is a stationary armature in this case comprising the two arc-shaped elements one located on each of opposite sides of the armature it, so that when the magnet 29 is rotated to carry the poles from the armature it they will pass over the stationary armature members 33. The members 33 may be secured to the base by any suitable means such for example as lugs 33a passing through the base and bent over on the under side. There is also a slight clearance between the poles 3i! and the armature elements 33, about the same as that between these poles and the armature it, so that the wmatures will not freeze to the magnet and there will be no friction between them. When the magnet 29 is turned so that its poles are over the armature IS the magnetic or flux circuit is through the magnet and the armature 18. Therefore the armature is attracted toward the magnet and it is shifted against the action of the spring II to carry the contact ll into engagement with the contact it to close the circuit. When the magnet is turned to carry its poles away from their position over the armature l8,as indicated in dotted lines in Fig. 2, they move over the members 33 of the stationary armature 32 and the magnetic or flux circuit is through the magnet and the armature 82, thus relieving the attraction of the magnet on the armature i8, permitting the spring M to shift the contact away from the contact 69 to open the circuit, as indicated in Fig. 4; As in this position the flux is transferred from the movable armature to the stationary armature there is no pull of the movable armature on the magnet to resist this movement, and therefore the only force required to turn the magnet is that of the friction of the shaft Zn in its bearing. Furthermore, the movement required of the magnet from the position attracting the armature it to a position releasing this armature is very small, so only slight movements of the magnet are required between the on and ofi. positions of the switch. In operating the switch the magnet may be entirely rotated or m;rely oscillated or reciprocated, depending on the use and application in which it is employed.
The parts may be enclosed by a suitable cover or casing C. 1
Another arrangement is shown by way of example in Figs. 5 to '7. In this case the spring contact is the same as in Figs. 1 to d but the operating magnet 34 corresponding to the magnet 253 is mounted differently. In this case it is mounted on a supportilt pivoted on a short shaft or stud 3h mounted in a supporting bracket 32 secured to the base it by any suitable means, such as a rivet 3. The support 35 includes an operating means such as a handle 39. It will be seen that with this arrangement oscillation of the support 35 on its pivot 36 will shift the magnet 36 and its poles to back and forth across the armature it, and when they are over this armature the magnetic or flux circuit is through the magnet 3 and the armature it causing the armature to be attracted by the magnet and shifted to carry the contact i'l into engagement with the contact is to close the circuit. When the magnet is shifted away from the armature it is released so that the spring carries the contact ii away from the contact it to open the circuit as indicated in dotted lines Fig. 5.
On opposite sides .of the armature it are mounted stationary armature members (it, there being one on each side of the armature it if the magnet is mounted to be swung in either direction from the armature it. If it is intended to be swung in one direction only, then only one armature member to will be required. As the magnet is mounted to swing about the center of the pivot 36 the free ends ii of the poles 3!] swing in an arc of a circle. It is therefore preferred to curve the ends of these poles on an arc with the pivot as the center and also to correspondingly curve the faces 62 of the'armature members it so that the faces of the poles move substantially parallel to the faces of the armature, although of course this arrangement is not absolutely necessary. The armature members Qt may be secured to the base by any suitable means such for example as the lugs 33 extending through and bent over on the underside of the base.
The operation in this case is the same as that in the first form shown. When the poles of the magnet are over the armature it, as shown in Figs. 5 and 6, the magnetic or flux circuit is through the magnet and the armature it, thus causing the magnet to attract the armature and shift it against the action of .the spring i i to bring the contact I] into engagement with the contact i9 to close the circuit. If the magnet is swung laterally to carry its poles from over the armature it to a position over one of the armature members (it, as indicated in Fig. '7, the magnetic or flux circuit is transferred from the armature it to the corroesponding armature member 3 so that it is now through this armature memher and the magnet, which releases the attraction of the magnet on the armature i8 permit ting the spring ii to shift the contact it away from the contact 99 to open the circuit. Here again as in the first form, as the magnetic or flux circuit is transferred from the movable armature to the stationary armature there is no pull of the movable armature on the magnet to resist its swinging movement, so that the only resistance to movement of the magnet is that within the pivotal bearing 36 or any other operating means that may be employed. Also the movement of the magnet from a position attracting the armature it to one releasing it is very small so that very little shifting of the magnet is required to open and close the switch. There also is a slight clearance maintained between the poles of the magnet 36 and the armatures it and 62 to eliminate friction and prevent freezing of the armature to the magnet.
It is to be understood that the arrangements shown and described are illustrated merely by way of example and that any of numerous different arrangements may be used and any of numerous operating means for the movable magnet may be employed, such for example as any of the well known switch operating devices, as push off buttons, hick-oft devices, and so forth.
Having thus set forth the nature of my invention, what I claim is:
1. An electric switch comprising a movable contact, an armature connected therewith, a magnet mounted for movement to and from a position over the armature to shift and release it to operate the contact, and a stationary armature at one side of the first armature over which the magnet moves as it is shifted from the first armature, both armatures being always spaced from the magnet.
2. In an electric switch, a movable contact, a movable armature for shifting the contact, a magnet movable to and from aposition adjacent the armature to attract and release it, and a second armature arranged so that as the magnet moves from the first armature it approaches the second to transfer the magnetic field from the first to the second armature, both armatures being always spaced from the magnet.
3. An electric switch comprising a spring support, a movable contact carried by said support, an armature on the support, a magnet mounted for movement to a position adjacent the armature to attract it to shift the contact, and a sec-- ond armature adjacent the first and toward which the magnet moves as it leaves the first armature to transfer its flux to the second armature, both armatures being always spaced from the magnet.
4. An electric switch comprising a movable contact, an armature connected therewith for shifting it, a substantially U-shaped magnet they are shifted from the first armature, both armatures being always spaced from the magnet.
5. An electric switch comprising a spring contact support. an armature mounted on said support, a substantially U-shaped magnet movable to and from a position with its poles over the armature to shift the "armature and support against the action of the spring, and a second armature adjacent the first armature over which the poles move as they leave the first armature, both armatures being always spaced from the magnet.
6. An electric switch comprising a movable contact, an armature connected therewith, a substantially U-shaped magnet having spaced poles and mounted to turn about an axis extending longitudinally of the poles, said poles movable to a position closely over the armature during its turning movement to shift the armature, other armature means laterally of the first ar mature over which the poles move during other parts of their turning movement to release the first armature, both armatures being always spaced from the magnet, and means for turning the magnet,
'I.'An electric switch comprising a movable contact, an armature connected therewith, a magnet having spaced poles mounted te move to and from a position over the armature to shift the armature, other armature means laterally of the first armature over which the poles move as they leave the first armature to release it, 5 both armatures being always spaced from the magnet, and means for shifting the magnet.
8. An electric switch comprising a movable contact, an armature connected therewith, a magnet having spaced poles mounted to swing 1o laterally to and from a position over the armature to shift it, another armature at one side of the first armature over which the poles move as they leave the first armature to release it, both armatures being always spaced from the mag- 5 me, and means for shifting the magnet.
9. In a ,device of the character described, a movable armature, a magnet mounted for movement to and from a position adjacent the armature to shift and release it, armature 20 means laterally of the first armature over which the magnet moves as it leaves the first armature to release it, both armatures being always spaced from the magnet, and means for shifting the magnet,
25 HARVEY HUBBELL.
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Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2473789A (en) * 1946-03-25 1949-06-21 Crise Electric Mfg Company Thermostatically operated switch
US2518138A (en) * 1947-10-18 1950-08-08 Gen Electric Switch for speed regulators
US2519025A (en) * 1946-03-29 1950-08-15 George W Crise Hermetically sealed thermostatic switch
US2520935A (en) * 1945-02-03 1950-09-05 Hubbell Harvey Magnetically operated switch
US2521723A (en) * 1945-02-03 1950-09-12 Hubbell Harvey Magnetically controlled switch
US2544979A (en) * 1947-10-20 1951-03-13 Eastman Oil Well Survey Co Apparatus for orienting tools in well bores
US2546647A (en) * 1946-08-01 1951-03-27 Automatic Elect Lab Magnet operated sealed switchboard
US2548581A (en) * 1949-03-04 1951-04-10 Gen Electric Magnetic switching device
US2555571A (en) * 1948-06-11 1951-06-05 Allen E Chisholm Magnet operated switch
US2560814A (en) * 1947-08-02 1951-07-17 Sun Electric Corp Magnetic rotor operated switch
US2624122A (en) * 1947-08-23 1953-01-06 K T Lab Inc Inspection gauge
US2681960A (en) * 1949-11-29 1954-06-22 John A T Ellison Control device for parking meters
US2779900A (en) * 1953-04-07 1957-01-29 North Electric Co Switch member
US2793265A (en) * 1952-02-25 1957-05-21 North Electric Co Methods of and means for effecting magnetic armature actuation
US2809249A (en) * 1953-04-14 1957-10-08 North Electric Co Switch members
US2915606A (en) * 1956-09-13 1959-12-01 Berthold A Knauth Mechanism for measuring linear flow in flowmeters as a function of rotary motion therein
US2945928A (en) * 1958-07-01 1960-07-19 Robertshaw Fulton Controls Co Magnetic switches
US3284743A (en) * 1965-05-10 1966-11-08 Westinghouse Electric Corp Magnetic switching device
US3291389A (en) * 1963-05-09 1966-12-13 Rockwell Mfg Co Metering system and components thereof

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2520935A (en) * 1945-02-03 1950-09-05 Hubbell Harvey Magnetically operated switch
US2521723A (en) * 1945-02-03 1950-09-12 Hubbell Harvey Magnetically controlled switch
US2473789A (en) * 1946-03-25 1949-06-21 Crise Electric Mfg Company Thermostatically operated switch
US2519025A (en) * 1946-03-29 1950-08-15 George W Crise Hermetically sealed thermostatic switch
US2546647A (en) * 1946-08-01 1951-03-27 Automatic Elect Lab Magnet operated sealed switchboard
US2560814A (en) * 1947-08-02 1951-07-17 Sun Electric Corp Magnetic rotor operated switch
US2624122A (en) * 1947-08-23 1953-01-06 K T Lab Inc Inspection gauge
US2518138A (en) * 1947-10-18 1950-08-08 Gen Electric Switch for speed regulators
US2544979A (en) * 1947-10-20 1951-03-13 Eastman Oil Well Survey Co Apparatus for orienting tools in well bores
US2555571A (en) * 1948-06-11 1951-06-05 Allen E Chisholm Magnet operated switch
US2548581A (en) * 1949-03-04 1951-04-10 Gen Electric Magnetic switching device
US2681960A (en) * 1949-11-29 1954-06-22 John A T Ellison Control device for parking meters
US2793265A (en) * 1952-02-25 1957-05-21 North Electric Co Methods of and means for effecting magnetic armature actuation
US2779900A (en) * 1953-04-07 1957-01-29 North Electric Co Switch member
US2809249A (en) * 1953-04-14 1957-10-08 North Electric Co Switch members
US2915606A (en) * 1956-09-13 1959-12-01 Berthold A Knauth Mechanism for measuring linear flow in flowmeters as a function of rotary motion therein
US2945928A (en) * 1958-07-01 1960-07-19 Robertshaw Fulton Controls Co Magnetic switches
US3291389A (en) * 1963-05-09 1966-12-13 Rockwell Mfg Co Metering system and components thereof
US3284743A (en) * 1965-05-10 1966-11-08 Westinghouse Electric Corp Magnetic switching device

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