US3194912A

US3194912A - Double snap-action magnetically actuated toggle switch

Info

Publication number: US3194912A
Application number: US317941A
Authority: US
Inventors: Donald H Mink
Original assignee: Molex Products Co
Current assignee: Molex LLC
Priority date: 1963-10-22
Filing date: 1963-10-22
Publication date: 1965-07-13
Anticipated expiration: 1982-07-13

Description

July 13, 1965 D. H. MINK 3,194,912

' DOUBLE SNAP-ACTION MAGNETICALLY AOTUATED TOGGLE SWITCH Original Filed Aug. 24, 1960 I NVENTOR.

Jami/flak United States Patent Aug. 24, 1960. This application Oct. 22, 1963, Ser. No.

8 Claims. (Cl. 200-67) This is a continuation of application Serial No. 51,734 filed August 24, 1960, now abandoned. This invention is concerned with the art of electric switches, particularly snap switches.

As is well known, when switch contacts are moved in and out of engagement, there is a tendency for arcing to occur across the contacts. This burns the contacts, and eventually renders them inoperative. Accordingly, various expedients have been developed for causing switches to open and close with a snap action. In general, such switches have used spring devices which in some respects have been entirely satisfactory. However, such switches have been subject to spring fatigue and sometimes have been damaged or thrown out of adjustment by vibration or temperature changes. Furthermore, such switches have generally been somewhat com plicated mechanically, and often have involved difficult fabrication problems.

Accordingly, it is an object of this invent-ion to provide an improved and simplified snap switch.

Furthermore, it is an object of this invention to provide a snap switch which has no components under cornpression or tension at any time, thereby substantially eliminating fatigue of components.

It is another object of this invention to provide a snap switch which is substantially unaffected by vibration or temperature changes. I

Still another object of this invention is to provide an electric switch wherein a common agency is used for pivoting the switch contacts and for imparting a snap action thereto. 2

A more specific object of this invention is to provide an electric switch incorporating a permanent magnet attracted by certain components of the switch into predetermined position.

A further specific object of this invention is to provide a magnetic snap switch in which a manually controlled actuator in magnetic cooperation with contact means is movable relative'to the contact means and over-centers relative thereto before movement of the contact means.

Yet another object of this invention is to provide a magnetic snap switch in which magnetic attraction insures a positive pressure between engaged contacts.

Other and further objects and advantages of the present invention will be apparent from the following description when taken in connection with accompanying drawings wherein:

FIG. 1 is a logitudinal sectional view taken through the center of the switch from front to back, showing a switch as mounted behind a wall plate or other surface;

FIG. 2 is a longitudinalsectional view through the switch as taken substantially along line 22 in FIG 1, parts being broken away for clarity of illustration;

FIG. 3 is a horizontal sectional view taken substantially along line 3-3 in PEG. 1;

FIG. 4 is a detail sectional view of the switchactuator and armature mounted thereon;

FIG. 5 is a perspective view of the molded pivot in the switch housing; FIG. 6 is a fragmentary side view showing one cooperation of the magnetand armature; and

3,194,912 Patented July 13, 1965 See FIG. 7 is a view similar to FIG. 6 showing a different cooperation'insuring positive pressure on engaging contacts.

Referring now in greater particularity to the drawings, and first to FIG. 1, there will be seen a switch construction in accordance with the principles of this invention and designated generally by the numeral 10. It is shown as mounted in a wall bracket 12 and covered by a wall plate 14 both of conventional design. However, it will be appreciated that this is an immaterial detail, the switch lending itself to virtually any type of mounting requirement. The switchincludes a housing 16 enclosing it on all six sides, but with a wide slot in its front face to receive the actuator 18. The actuator 18 is constructed of any suitable nonconductive substance, and its appearance as viewed from the outside of the wall plate 14 is of the conventional toggle type. The form of the actuator 18 as distended inside the switch housing 16 is that of a general crescent shape, and with side arms 20 extending to a point near the center of the switch case. The arms have rounded noses 21 pivoted in saddles 23 molded with the side of the housing 16.

The actuator 18 carries an armature 24 of soft iron between the side arms 20, the underside of the actuator being recessed to receive said armature which is cemented in place. The armature is of more or less fla practically sheet metal construction, and bent at its transverse center line to describe a wide obtuse angle longitudinally. It will be apparent that the apex is substantially at the radius center of the noses 21. Inwardly directed, confronting teats 22 are formed in two relatively widely spaced arms 28 comprising two end flanges of a generally L-shaped metal bracket 26, the short leg 30 of which is broadened, formed and threaded to receive a conventional terminal screw 32. It will be apparent that these teats are also substantially aligned with the radius center of said noses 21, whereby all of the operating parts pivot about a substantially common center.

A small permanent bar magnet 36 is fitted inside the arms 28 of the L-shaped bracket 26 and is carried in a metal trough or channel 38. This channel is provided with dimples 39 receiving the teats 22, so that the magnet and channel pivot therea-bout. Both the upper and lower ends of the web of said channel 38 are provided with small circular

electrical contact points

40 and 42 respectively. The point 42 cooperates with a point 44 on the end of a small bracket 46 which is bent, formed and threaded to receive anotherconvcntional terminal screw 48. The upper contact 40 of said channel 38 is opposite a similar contact point 50 at the end of a small bracket 52. The bracket 52 is threaded for receipt of a screw 53 for use of the switch as a single pole double throw switch. Without this screw, the switch is a single pole single throw switch.

A leg of the armature and the adjacent surface of the magnet may actually contact as shown in FIG. 6, but preferably the walls 54 of the saddles 23 are at such relative angles that they contact the arms 20 to limit or confine movement of the actuator so that it cannot travel far enough in either direction to allow actual contact between either leg of the armature and the adjacent surface of the magnet. Thus, there will be maintained a slight air gap as shown at 56 in FIG. 7 between a leg of the armature 'and'the adjacent surface of the end of the magnet carrying the contact now separated from the adjacent fixed contact. With this arrangement, continuing pressure is maintained between the closed contacts, that is, the contact at the opposite end of the magnet and the adjacent fixed contact. As either leg of the armature is brought near the face of the magnet, the magnet is caused to spring toward that leg of the armature. This imparts a snap action to the magnet and channel which causes the contacts at one of said channcls extremities to open, and at the other to close. Assuming

screws

32 and 48 are being used as terminal screws for an electrical circuit, said circuit may be completed through the L- shaped bracket and magnet trough when

contacts

42 and 44 are brought together by means of the above described snap action. Correspondingly, the circuit is opened when these two contacts are separated by means of said snap action operating in reverse. In either csae, the magnetic attraction rapidly completing or breaking contact minimizes any associated arcing of the contacts.

The various embodiments of the invention as herein shown and described will be understood as being exemplary. Various changes in structure will, no doubt, occur to one skilled in the art, and are to be understood as forming a part of this invention insofar as they fall within the spirit and scope of the appended claims.

The invention is claimed as follows:

1. A snap action switch comprising a base, fixed contact means carried by said base, a permanent bar magnet pivoting on its transverse central axis about a pivot point fixed to said base and having a substantially flat face presenting a half of the flat face on opposite sides of the transverse axis, movable electrical contact means pivotally mounted on said base and connected to said permanent bar magnet, a magnetically susceptible armature means of substantially angular longitudinal section having an apex with angularly disposed portions on either side thereof, means pivotally mounting said armature means substantially at its apex about said fixed pivot point confronting the substantially fiat face of said magnet whereby pivoting of said armature mean-s in either direction causes a corresponding one of its angularly disposed portions to be brought relatively near to the adjacent half of the flat face of the magnet on one side of the transverse axis with resultant snap movement of the adjacent half of the flat face of the magnet and contact with the adjacent angularly disposed portion of the armature means and with the other half of the flat face of the magnet on the opposite side of the transverse axis disengaging the other angularly disposed portion of the armature means to thus effect engagement and disengagement between the fixed and movable contact means.

2. A snap action switch comprising a base, fixed contact means carried by said base, a permanent bar magnet having a substantially fiat face and pivoting on its transverse central axis about a pivot point fixed to said base to present a half fiat face of the magnet on opposite sides of said transverse axis, movable electrical contact means pivotally mounted on said base, and connected to said permanent bar magnet, magnetically susceptible armature means of substantially angular longitudinal section having an apex with angularly disposed portions on either side thereof, means pivotally mounting said armature means substantially at its apex about said fixed pivot point confronting the substantially flat face of said magnet whereby pivoting of said armature means causes one of its legs to be brought relatively near to an adjacent half of the fiat face of the magnet on one side of the transverse axis thereof with snap movement of the adjacent half of the fiat face of the magnet toward the adjacent leg of the armature means and with the other half of the flat face of the magnet moving away from the other leg of the armature means, and stop means on said base preventing contact of either half of the flat face of the magnet with the armature means to provide an air gap with magnetic force acting between an adjacently positioned leg of the armature means and magnet face holding the opposite contacting fixed and movable contact means aggressively in mutual engagement.

3. A snap action switch comprising a base, fixed contact means carried by said base, a permanent bar magnet having a substantially fiat face and providing on its transverse central avis about a pivot point fixed to said base to present a half fiat face of the magnet on opposite sides of said transverse axis, movable electrical contact means pivotally mounted on said base and connected to said permanent bar magnet, magnetically susceptible armature means of substantially angular longitudinal section having an apex with angularly disposed portions on either side thereof, means pivotally mounting said armature means substantially at its apex about said fixed pivot point confronting the substantially fiat face of said magnet whereby pivoting of said armature means in either direction causes a corresponding one of its angularly disposed portions to be brought relatively near to the adjacent half of the fiat face of the magnet on one side of the transverse axis with resultant snap movement of the adjacent half of the flat face of the magnet and with the other half of the flat face of the magnet on the opposite side of the transverse axis moving away from the other angularly disposed portion of the armature means to thus effect engagement and disengagement between the fixed and the movable contact means.

4. A snap action switch comprising a base, fixed contact means carried by said base, first magnetic means having a flat face and pivoted on its transverse central axis about a pivot point fixed to said base to present a half fiat face of the first magnetic means on opposite sides of said transverse axis, movable electrical contact means pivotally mounted on said base and interconnected with said first magnetic means, second magnetic means of substantially angular longitudinal section having an apex and having angularly disposed portions on either side thereof, one of said magnetic means comprising a permanent magnet with a pole adjacent the opposite ends thereof and the other of said magnetic means being of magnetically susceptible material, means pivotally mounting said second magnetic means substantially at its apex about said fixed pivot point and confronting the substantially fiat face of the first magnetic means, whereby pivoting of said second magnetic means in either direction causes a corresponding one of its angularly disposed portions to be brought relatively near to the adjacent fiat face of the first magnetic means on one side of the transverse axis with resultant snap movement of the adjacent half face of the first magnetic means and with the other half of the flat face of the first magnetic means on the opposite side of the transverse axis moving away from the other angularly disposed portion of the second magnetic means to thus effect engagement and disengagement between the fixed and the movable contact means.

5. A snap action switch as set forth in claim 4 wherein the first and second magnetic means move into substantial engagement with one another.

6. A snap action switch as set forth in claim 4- and further including means for maintaining said first and second magnetic means out of engagement with one another.

7. A snap action switch comprising a housing having a pair of opposed substantially V-shaped saddles therein, each of said saddles having a pair of diverging walls and a rounded apex, fixed contact means carried on said housing, first magnetic means pivoting on a transverse central axis about pivot means fixed to said housing, said first magnetic means having a substantially flat face, movable electrical contact means pivotally mounted on said housing and connected to said first magnetic means for pivoting therewith, an actuator having rounded nose means received in said saddles and pivotable therein, second magnetic means fixed to said actuator and of substantially angular longitudinal section having an apex and having a pair of angularly disposed portions on either side of said apex, said apex being substantially at said pivot point, said second magnetic means substantially confronting said first magnetic means, :one of said magnetic means comprising a permanent magnet with a pole adjacent the opposite ends thereof and the other of said magnetic means being of magnetically susceptible material pivotal movement of said actuator moving one of the angnlarly disposed portions of said second magnetic means relatively near to the adjacent end of the first magnetic means and causing said adjacent end of said first magnetic means to be drawn toward said second magnetic means with a snap action causing engagement and disengagement between said fixed and mova'oie contact means.

it A snap action switch as set forth in claim '7 wherein the diverging walls of said saddles limit movement of said actuator with said first and second magnetic means out of Contact with one another.

References Cited by the Examiner UNITED STATES PATENTS 1,989,277 1/35 Jeffrey.

2,120,938 6/38 Kronmiller 200-6 X 2,628,296 2/53 Diilrnan 200-87 X 2,935,583 5/60 Howell 200 19 X 2,951,129 8/60 Mink 200 67 2,971,068 2/61 Wegnei' 200-67 BERNARD A. GILHEANY, Primary Examiner.

Claims

1. A SNAP ACTION SWITCH COMPRISING A BASE, FIXED CONTACT MEANS CARRIED BY SAID BASE, A PERMANENT BAR MAGNET PIVOTING ON ITS TRANSVERSE CENTRAL AXIS ABOUT A PIVOT POINT FIXED TO SAID BASE AND HAVING A SUBSTANTIALLY FLAT FACE PRESENTING A HALF OF THE FLAT FACE ON OPPOSITE SIDES OF THE TRANSVERSE AXIS, MOVABLE ELECTRICAL CONTACT MEANS PIVOTALLY MOUNTED ON SAID BASE AND CONNECTED TO SAID PERMANENT BAR MAGNET, A MAGNETICALLY SUSCEPTIBLE ARMATURE MEANS OF SUBSTANTIALLY ANGULAR LONGITUDINAL SECTION HAVING AN APEX WITH ANGULARLY DISPOSED PORTIONS ON EITHER SIDE THEREOF, MEANS PIVOTALLY MOUNTING SAID ARMATURE MEANS SUBSTANTIALLY AT ITS APEX ABOUT SAID FIXED PIVOT POINT CONFRONTING THE SUBSTANTIALLY FLAT FACE OF SAID MAGNET WHEREBY PIVOTING OF SAID ARMATURE MEANS IN EITHER DIRECTION CAUSES A CORRESPONDING ONE OF ITS ANGULARLY DISPOSED PORTIONS TO BE BROUGHT RELATIVELY NEAR TO THE ADJACENT HALF OF THE FLAT FACE OF THE MAGNET ON ONE SIDE OF THE TRANSVERSE AXIS WITH RESULTANT SNAP MOVEMENT OF THE ADJACENT HALF OF THE FLAT FACE OF THE MAGNET AND CONTACT WITH THE ADJACENT ANGULARLY DISPOSED PORTION OF THE ARMATURE MEANS AND WITH THE OTHER HALF OF THE FLAT FACE OF THE MAGNET ON THE OPPOSITE SIDE OF THE TRANSVERSE AXIS DISENGAGING THE OTHER ANGULARLY DISPOSED PORTION OF THE ARMATURE MEANS TO THUS EFFECT ENGAGEMENT AND DISENGAGEMENT BETWEEN THE FIXED AND MOVABLE CONTACT MEANS.