US2924682A - Magnetically actuated switches - Google Patents

Magnetically actuated switches Download PDF

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US2924682A
US2924682A US66327057A US2924682A US 2924682 A US2924682 A US 2924682A US 66327057 A US66327057 A US 66327057A US 2924682 A US2924682 A US 2924682A
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switch
magnet
actuator
door
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George A Winterburn
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George A Winterburn
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    • HELECTRICITY
    • H01BASIC ELECTRIC 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
    • H01H36/0073Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding actuated by relative movement between two magnets

Description

G. A. WINTERBURN 2,924,682

MAGNETICALLY ACTUATED SWITCHES Feb. 9, 1960 2 Sheets-Sheet 1 Filed June 3, 1957 MW W My HM N? 4 mi W, a I 1 a Z 1 .v w y hww a r W J fly Feb. 9, 1960 e. A. WINTERBURN 2,924,682

MAGNETICALLY ACTUATED SWITCHES 2 Sheets-Sheet 2 Filed June 3, 1957 Gear 8 1/5. lI Zred erJur/z United States Patent 2,924,682 MAGNETICALLY ACTUATED swrrcnns George A. Winterburn, Putnam, Conn.

' Application June 3, 1957, Serial No. 663,270

The invention relates to magnetic control apparatus for electric switches, of the type wherein portions, including a switch actuator, of a magnetic circuit are located on relatively movable objects, and changes in the magnetic field due to a change of the relative position of the objects cause actuation of a switch.

Objects of the invention are to provide door or window or, generally speaking, closure operated switches which are without or with insignificant mechanical adjustment capable of incorporation in closure arrangements of all commonly occurring types, to provide apparatus of the above indicated type which permits the use therein of commercially available electric switches, to provide such apparatus which can be used either for closing or opening an electric circuit in response to movement of either normally closed or normally open closure elements, to provide a switch actuation which is suitable for burglar alarm systems, to provide a limit switch such as for terminating the operation of electrically driven closure devices such as garage or elevator doors, to provide for a momentary switch closure giving a signal when a door or window is being opened or closed, to provide a signal sender indicating when a door has been closed, such as for use on fire doors in factories, to provide a closure control switch which is easily and without mechanical changes adaptable for use on sliding as well as swinging closures, to provide magnetically operated switches for the above mentioned and other uses which can be arrested in a given position, or rendered inoperative or lockedout by a very simple and easily operated expedient, and to provide generally speaking apparatus of this type which is comparatively inexpensive and yet fully reliable, which can be easily and inconspicuously installed, and which is very versatile and adaptable for many purposes.

4 A summary of the invention will serve briefly to indicate various aspects of its nature and substance, for accomplishing the above objects, as follows.

.Switch control assemblies for mounting on and operation by two relatively moving members such as a door or window and its frame comprise, for mounting on one of the closure members, a support such as a box having 2,924,682 Patented Feb. 9, 1960 members approaching each other or moving from each other as the case may be.

In an important practical aspect of the invention, a slide of magnetic material is mounted opposite an actuating permanent magnet, for example on the face of a supporting box, and arranged for movement directly into the field of at least one of the poles of the permanent magnet, such that the permanent magnet on the actuator lever can be attracted by moving the slide thereunder thereby bringing into, and retaining the switch in the same transferred condition to which it would be moved by the magnetic body on the other closure member.

These and other objects and aspects of the invention will appear from the following description of several typical embodiments illustrating its novel characteristics.

The description refers to drawings in which:

Fig. 1 is the front elevation of a box for mounting the switch actuating assembly according to the invention, with the second magnetic body omitted;

Fig. 2 is a section on lines 22 of Fig. l and showing a slug constituting a magnetic body;

Fig. 3 is a section similar to Fig. 2, but in actuated condition with the lock-out slide inefiective, with a permanent magnet as second body instead of the slug of Fig. 2, and with the box omitted;

Fig. 4 is a section similar to Fig. 3, but with the lockout slide in action and omitting the second magnetic body;

Fig. 5 is a section on 5-5 of Fig. 4;

Fig. 6 is a section on 6-6 of Fig. 4;

Fig. 7 is an elevation of the actuating lever of an em bodiment which employs an iron armature instead of a permanent magnet on the actuating lever which is otherwise similar to that shown in Figs. 2 to 5;

Fig. 8 is a section on lines 8-8 of Fig. 6;

Fig. 9 is an elevation, similar to Fig. 1, of a face plate but without the look-out member shown in Fig. 1;

Figs. 10 to 13 are diagrams of a swinging door and of a sliding door respectively, indicating various possibilities of employing apparatus of the present type, Figs. 10 and 12 being front elevations and Figs. 11 and 13 sections on lines 11 and 13 of Figs. 10 and 12, respectively; and

Figs. 14 and 15 are diagrams indicating various possibilities of actuator arrangement.

The complete switch control assembly comprises two units, indicated at A and B of Fig. 2 as arranged on a non-magnetic face that can be mounted flush with a side or face of that member, a switch fastened on the support, such as within a box, having an actuator that responds to pressure thereon and exerts a biasing force against such pressure, an actuator lever pivoted on the switch or support and carrying a magnetic actuating body such as a permanent magnet or a magnetizable plate adjacent to the face and capable of moving the actuator lever and the actuator by magnetic force against the biasing force, the biased actuator normally preventing such movement including operation by gravity and, for mounting on the other closure member, a second magnetic body, at least oneof these bodies developing a magnetic field suflicientlystrong to move the other magnetic body within or upon removal from a common magnetic circuit. Thus, if the actuator is moved against the biasing force, the switch is transferred upon the relatively moving closure two relatively movable closure members.

In Figs. 1 and 2, numeral 21 indicates, as a support of unit A, a switch box of conventional design and which can be fastened to a recess of the jam of a door or window, or to a door or window itself, or to one of two moving members generally, by means of screws 22. A striker plate 23 is fastened to the flanges 21.1 of the box by means of screws 24. The striker plate 23 is made of non-magnetic material such as for example brass which can be nickel or chromium-plated or otherwise finished.

In the above-mentioned important practical embodiment of the invention which incorporates a lock-out device, the striker plate has a slot 31 (Figs. 1 to 4, 6 and 8) and there-behind a lock-out slide 32 of magnetic material to which is fastened a chamfered lock-out operating slide button 39 such that it holds the magnetic lock-out slide 32 against the inner side of the striker plate 23, as clearly shown in Fig. 8. It will be evident that the button 39 can be moved with a fingernail, from the position indicated in Figs. 1 and 2 to that indicated in Fig. 4.

Fastened to the striker plate 23 is a mounting bracket 35 (Fig. 6), such as by welding or brazing. Fastened to this bracket, by means of screws 35.1, 35.2 is a conventional microswitch 41 (Figs. 2 to 4) which has an actuator pression, being normally in protruding position as shown in Fig. 2, whereas it operates the switch when it' is depressed towards the switch housing as shown in Figs. 3 and 4. It will be understood that. such depression can either open or close the switch contacts proper, ortransfer a double throwswitch during the period of depression of the actuator, or perform any conventional momentary or until further actuation lasting switching operation.

Mounted on the flanges 41.1, 41.2 (Fig. 5) of the switch housing 41 is a pivot pin 43 which carries a double armed lever 45. The shorter arm 45.1 rests on or is somewhat distanced from the actuator 42, whereasthe longer arm 45.2 hasscrewed or otherwise fastened thereto a U-shaped magnet 51. It should be noted that the switch actuator 42 is biased in such a manner .that it will resist depression by the actuator lever 45 so long as the magnet 51 is not attracted, in any position of the switch,

including that in which the magnet 51 is pulled downwardly by gravity if the box should be mounted on the horizontal portion of a closure frame. Microswitches of this type are at this time easily available on the market, and it will be understood that the actuating lever can be mounted, in proper relation to a biased actuator such as 42, in any convenient manner. If it is desirable to prevent vibration, the lever 45 can be immobilized in normally inoperative position, for instance by extending the fastening screw 52 of the magnet such that it touches in inoperative position the switch housing as indicated at 52.1 of Fig. 2.

The conventional switch terminals are indicated at 41.8 and 41.9 of Fig. 2.

The second unit B is mounted on the second closure member in a path having a common region with unit A. This second unit is illustrated by the iron slug 55 of Fig. 2 or the U-shaped magnet 56 of Fig 3. The iron slug 55 can be fastened by means of prongs 55.1 or by means of a screw such as indicated at 56.1 of Fig. 3 for fastening the magnet 56. In many instances iron slugs or patches as shown in Fig. 2 are fully suflicient for the proper operation of this device, and this construction permits'extremely simple mounting merely by means of a hammer which is often of importance in installations of this type.

with the look-out slide 32 in the position shown in Figs. 2 and 3, if the slug 55 or the magnet 56 approaches the face plate 23 and hence the magnet 51,'the latter will be attracted, overcomes the bias of actuator 42, and operates the switch within the housing 41, provided that the polarity of the magnets is as indicated in Fig. 3 if two magnets are used.

If it is desired to render the switch inoperative, the lookout slide 32 of magnetic material is moved by means of the button 39 until it comes into the position indicated in Fig. 4. In this position it attracts magnet 51, and moves the switch into the condition that corresponds to the depression of the actuator by way of unit B, as indicated in Fig. 3. It is thus possible to render unit A independent of the relative position thereto of unit B, retaining the switch in the position that is normally brought about by the slug 55 or the magnet 56.

Instead of using a magnet 51 on the switch mechanism of Figs. 2 to 5, an iron armature can be used for that purpose as indicated in Fig. 7. The construction of the lever and its pivot pin 43 are the same in both instances. It will be evident that, if an iron body 61 is used as a switch actua'tor in unit A, a magnet 56 must be used in unit 18 instead of the iron slug 55 as shown in Fig. 2. It'will be further evident that the lock-out device is ineifective with an actuator lever according'to Fig. 7. In this instance a plain striker plate of nonmagnetic material such as shown at 23.1 of Fig. 9 can be substituted which of course is also used: if, for some reason, it is not desired to employ a lock out device together with a magnetic actuator'lever sucna'ssliown in Figs. 2 to 4.

Figs. wand 11 indicate several possibilities of installing the device according to the invention on a swinging door or similar closure arrangement. In these figures, the unit A can be mounted on either side of the frame or at the horizontal part thereof as indicated at A1, A2 and A3, and the unit B can be applied to the corresponding points of the door proper as indicated in Figs. 10 and 11. It will be evident that the positions of A and B can be exchanged, without eifect on the operation, although it is of course easier to leadthe wiring to a stationary box. It will also be evident that the switch 4:1 can be either open or closed in normal position, and that either an open door or a closed door can be considered normal; the most prevalent installation will be that shown in Figs. 10 and 11, with the switch open when the door is closed and with the switch closed and a lamp on when the door is open; if it is then desired to keep the door open such as for airing, the lamp can be turned off by moving the look-out slide of unit A into the position of Fig. 4.

Figs. 12 and 13 indicate additional possibilities, including those of indication of position, of signalling and. of giving an alarm, as follows. In position A5, B5, the device operates as described above with reference to Figs. 10 and 11. In position A6, B6, the device can be used for indicating that the door II is fully closed. and locked relatively to door I. The switch of unit A6 is then normally open and sends a momentary impulse upon actuation by unit B6. A6 can be similarly used as an end switch for actuating a relay. device with the switch of A7 normally open, will deliver a signal when B7 passes A7; a burglar alarm can be arranged in analogous manner.

Figs. 14 and 15 indicate further possibilities of using the device according to the invention, as follows. According to Fig. 14, the magnet A8 when attracted by the iron patch A8, opens the switch s1 which is closed while B8 is removed from A8, for example when the door is open. Fig. 15 shows a single armed lever 45.5, pivoted at 43.1 which closes a normally open switch s2 when the magnet of 'B9 approaches that of A9. In both instances, the switch actuator bias is indicated by arrow b. It will be noted that Fig. 14 corresponds to the arrangement of Fig. 2, whereas Fig. 15 corresponds to the polarized arrangement of Fig. 3 with the diflerence that the polarities are opposite in Fig. 3, whereas they are equal in Fig. 15. Thus, assuming that the switch of Fig. 3 is normally open, attraction or" the magnet 51 on the double armed lever 45 closes the switch, while the same result is obtained by the repulsion of the magnet on thesingle armed lever of Fig. 15. It will now be evident that it is possible to arrange for a great variety of modes of operation simply by selecting a conventional switch, an actuator lever, and a magnetic circuit suited for the purpose at hand,;be it opening or closing a switch or giving a momentary impulse, upon approach, passing, or distancing of the two magnetic bodies or locking-out the switch.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claim.

I claim:

A door or window switch assembly comprising: a switch unit for mounting on a door or window frame, including a switch box of the concealed type having a non-magnetic striker plate with a longitudinally extending slot, mounted in said box a switch enclosed in a housing and having a biased actuator extending from said housing, pivoted on said housing a two armed lever extending along said slot with the end of one arm opposite said actuator; a U-shaped magnet fastened to the other arm of said lever and facing said striker plate adjacent to said slot, said actuator being sufliciently biased to prevent actuation by the weight of said magnet and to press the lcveragainst In position A7, B7, the a said housing for immobilizing the magnet and lever in normal position, a lock-out plate of paramagnetic material slidingly movable in a straight path along said slot on the inside of said striker plate, and means on the out side of said striker plate for moving said lock-out plate into or from the field of said magnet; and an operator unit including an armature capable of attracting said magnet, for mounting on a door or Window in a path containing said striker plate in the region of said magnet; whereby said operator armature transfers the switch by depressing the actuator upon entering the region of the magnet, and said lock-out plate when moved into the field of the magnet attracts the magnet, depresses the actuator and retains the switch transferred regardless of the relative position of switch unit and operator unit.

References Cited in the file of this patent UNITED STATES PATENTS 725,259 Ki'tsee Apr. 14, 1903 2,566,053 Blakeslee Aug. 28, 1951 2,600,581 Schenendorf June 17, 1952 2,624,792 Fruh Jan. 6, 1953 2,734,123 Gerber Feb. 7, 1956 2,770,697 Kellett Nov. 13, 1956 2,802,074 Pass Aug. 6, 1957

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Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3017473A (en) * 1958-07-02 1962-01-16 Verger Nathan Magnetic switch
US3022398A (en) * 1959-05-15 1962-02-20 Fluidwick Company Inc Electric control device
US3155792A (en) * 1962-08-07 1964-11-03 Gen Electric Magnetic reed switch device
US3159196A (en) * 1961-05-02 1964-12-01 Adolf Ditting Protective device for cutting machines with cutting disc
US3159030A (en) * 1961-03-14 1964-12-01 Smith Corp A O Fluid meters
US3161742A (en) * 1961-08-24 1964-12-15 Specialties Dev Corp Magnetic intruder and fire deterctor
US3190174A (en) * 1962-03-22 1965-06-22 Charles Beseler Company Slide-actuate switch for photographic projector
US3226506A (en) * 1963-06-20 1965-12-28 Angrisani Aldo Magnetic device for circuit control
US3241258A (en) * 1962-03-22 1966-03-22 Charles Beseler Company Slide mount for photographic film
US3255532A (en) * 1962-04-04 1966-06-14 Motor Wheel Corp Magnetic measuring apparatus
US3368173A (en) * 1967-04-27 1968-02-06 Byron F. Wolford Hermetically sealed, pressure responsive, magnetically actuated switch device
US3368045A (en) * 1964-11-30 1968-02-06 Acme Machine Works Inc Flow indicator utilizing permanent magnets for switch actuation
US3410245A (en) * 1966-06-17 1968-11-12 Continental Instr Corp Alarm device
US3426166A (en) * 1966-06-09 1969-02-04 Int Standard Electric Corp Magnetic closure and switch for doors and similar devices
US3513273A (en) * 1968-09-19 1970-05-19 Harold J Qualheim Magnetically-controlled safety switch for food slicers
US3539741A (en) * 1969-08-08 1970-11-10 Mallory & Co Inc P R Magnetically activated door switch
US3569645A (en) * 1968-10-29 1971-03-09 Lawrence N Lea Tamperproof switch devices for burglar alarm systems, affording cordless connections across protected station separations
US3731025A (en) * 1971-07-14 1973-05-01 Sloan Valve Co Breath operated flushing arrangements
US3798627A (en) * 1972-09-15 1974-03-19 A Kaufman Door guard and alarm
US3890476A (en) * 1974-08-08 1975-06-17 Gen Motors Corp Appliance cabinet with actuated door switch
US4188739A (en) * 1978-06-15 1980-02-19 Caterpillar Tractor Co. Magnetic switch adjusting system
US4531029A (en) * 1982-01-08 1985-07-23 Currillies Trimble Cricket switch
US5007199A (en) * 1990-02-15 1991-04-16 Larmco Security, Inc. Anti-intrusion window
US5063372A (en) * 1990-06-22 1991-11-05 Ranco Incorporated Of Delaware Door ajar alarm for refrigeration unit
US5070319A (en) * 1990-06-22 1991-12-03 Ranco Incorporated Of Delaware Door ajar alarm for refrigeration unit
US6124792A (en) * 1998-11-25 2000-09-26 U-Haul International, Inc. Latch integrated, tamper resistant, electro-magnetic alarm switch

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US725259A (en) * 1897-05-20 1903-04-14 Isidor Kitsee Automatic cut-out.
US2566053A (en) * 1946-10-17 1951-08-28 Bristol Company Temperature control apparatus
US2600581A (en) * 1949-07-19 1952-06-17 Schenendorf Benjamin Magnetic circuit control for burglar alarms
US2624792A (en) * 1949-08-18 1953-01-06 Arthur W Fruh Closure member operated switch
US2734123A (en) * 1956-02-07 gerber
US2770697A (en) * 1954-04-01 1956-11-13 Alfred L Kellett Magnetic electrical switch
US2802074A (en) * 1956-03-07 1957-08-06 Sidney M Pass Cut-off switch for tractor

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2734123A (en) * 1956-02-07 gerber
US725259A (en) * 1897-05-20 1903-04-14 Isidor Kitsee Automatic cut-out.
US2566053A (en) * 1946-10-17 1951-08-28 Bristol Company Temperature control apparatus
US2600581A (en) * 1949-07-19 1952-06-17 Schenendorf Benjamin Magnetic circuit control for burglar alarms
US2624792A (en) * 1949-08-18 1953-01-06 Arthur W Fruh Closure member operated switch
US2770697A (en) * 1954-04-01 1956-11-13 Alfred L Kellett Magnetic electrical switch
US2802074A (en) * 1956-03-07 1957-08-06 Sidney M Pass Cut-off switch for tractor

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3017473A (en) * 1958-07-02 1962-01-16 Verger Nathan Magnetic switch
US3022398A (en) * 1959-05-15 1962-02-20 Fluidwick Company Inc Electric control device
US3159030A (en) * 1961-03-14 1964-12-01 Smith Corp A O Fluid meters
US3159196A (en) * 1961-05-02 1964-12-01 Adolf Ditting Protective device for cutting machines with cutting disc
US3161742A (en) * 1961-08-24 1964-12-15 Specialties Dev Corp Magnetic intruder and fire deterctor
US3190174A (en) * 1962-03-22 1965-06-22 Charles Beseler Company Slide-actuate switch for photographic projector
US3241258A (en) * 1962-03-22 1966-03-22 Charles Beseler Company Slide mount for photographic film
US3255532A (en) * 1962-04-04 1966-06-14 Motor Wheel Corp Magnetic measuring apparatus
US3155792A (en) * 1962-08-07 1964-11-03 Gen Electric Magnetic reed switch device
US3226506A (en) * 1963-06-20 1965-12-28 Angrisani Aldo Magnetic device for circuit control
US3368045A (en) * 1964-11-30 1968-02-06 Acme Machine Works Inc Flow indicator utilizing permanent magnets for switch actuation
US3426166A (en) * 1966-06-09 1969-02-04 Int Standard Electric Corp Magnetic closure and switch for doors and similar devices
US3410245A (en) * 1966-06-17 1968-11-12 Continental Instr Corp Alarm device
US3368173A (en) * 1967-04-27 1968-02-06 Byron F. Wolford Hermetically sealed, pressure responsive, magnetically actuated switch device
US3513273A (en) * 1968-09-19 1970-05-19 Harold J Qualheim Magnetically-controlled safety switch for food slicers
US3569645A (en) * 1968-10-29 1971-03-09 Lawrence N Lea Tamperproof switch devices for burglar alarm systems, affording cordless connections across protected station separations
US3539741A (en) * 1969-08-08 1970-11-10 Mallory & Co Inc P R Magnetically activated door switch
US3731025A (en) * 1971-07-14 1973-05-01 Sloan Valve Co Breath operated flushing arrangements
US3798627A (en) * 1972-09-15 1974-03-19 A Kaufman Door guard and alarm
US3890476A (en) * 1974-08-08 1975-06-17 Gen Motors Corp Appliance cabinet with actuated door switch
US4188739A (en) * 1978-06-15 1980-02-19 Caterpillar Tractor Co. Magnetic switch adjusting system
US4531029A (en) * 1982-01-08 1985-07-23 Currillies Trimble Cricket switch
US5007199A (en) * 1990-02-15 1991-04-16 Larmco Security, Inc. Anti-intrusion window
US5164705A (en) * 1990-02-15 1992-11-17 Larmco Security, Inc. Anti-intrusion window
US5063372A (en) * 1990-06-22 1991-11-05 Ranco Incorporated Of Delaware Door ajar alarm for refrigeration unit
US5070319A (en) * 1990-06-22 1991-12-03 Ranco Incorporated Of Delaware Door ajar alarm for refrigeration unit
US6124792A (en) * 1998-11-25 2000-09-26 U-Haul International, Inc. Latch integrated, tamper resistant, electro-magnetic alarm switch
US6249224B1 (en) 1998-11-25 2001-06-19 U-Haul International, Inc. Latch integrated, tamper resistant, electro-magnetic alarm switch

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