US2417438A - Electromagnetic switch - Google Patents

Description

March 18, 1947- J. F. O'BRIEN E-rAL ELECTROMAGN'ETIC SWITCH Filed Oct. 30, 1943 2 Sheets-SheetY l ...f/linffflllv* INVENToRs OSEPH F. OBRIEN TORNBY L S.BOYNTON BY March 1s. 1941. J. F; @BRIEN Em 2,411,438

ELECTROIIAGNETIC SWITCH 2 Sheets-Sheet 2 Filed Oct. 30, 1943 Patented Mar. 18, 1947 2,417,438 ELECTROMAGNETICl SWITCH Joseph F. OBrien, Jersey City, and Earl S. Boynton, East Orange, N. J., assignors to John B. Pierce Foundation, New York, N. Y., a corporation of New York Application October 30, 1943, Serial No. 508,298

7 claims. `(ci. 11s-341) l This invention relates to electromagnetic switches.

It is an object of the invention to provide an improved structural organization of the operatlng parts of said electromagnetic switch, to insure that all of the respective operating parts are precisely positioned .within the electromagnetic switch housing.

It is an object of the invention to provide an electromagnetic switch in which a snap spring or like operating structure, by solenoid induced movement, opens or closes the contacts of the electromagnetic switch, the relative position of the snap spring and the solenoid operator being disposed within the casing in a pre-established dimensional arrangement to insure accuracy of operation. l

It is an object of the invention to provide improved means for confining within the housing of a electromagnetic switch, the operating elements thereof.

It is an object of the invention to provide a electromagnetic switch with improved contact structures.

It is an object of the invention to provide an electromagnetic switch having a fixed and a movable contact organization, with improved means for cushioning the engagement between the xedand movable contact.

It is an object of the invention to provide an electromagnetic switch comprising a plurality of operating parts, with improved means for securing said operating parts within a housing, with a minimum of fastening or attachment means for said operating parts.

It is an object of the invention to provide an electromagnetic switch which is of simple, low cost construction, and which may be assembled, with accurately disposed securement of the operating parts, by means of unskilled labor.

According to a preferred form of the invention, the improved electromagnetic switch comprises an organization of fixed and movable contacts,

the movable contacts being brought into or out of engagement with the fixed contacts by solenoid actuators, operating through the agency of a snap spring. Secured to the base of the housing of the electromagnetic switch, on which base the xed contacts are positioned, are a plurality of side frame members, said members having at a pre-determined location with respect to the base structure, means to receive and position a sub-base which serves as the support for the operating elements of the electromagnetic switch. Positioned upon said sub-base, but not permanently affixed thereto, are a snap spring retainer and a solenoid actuator comprising a pair of individual solenoid cups between which, and in engagement with the rims thereof are located a pair of spacer members having inner peripheral flanges which collectively provide a cylindrical chamber within which a solenoid core is slidably positioned. The respective solenoid.cups, within which the operating solenoids are contained, are in stacked relationship one with the other,

y and may be inserted within the side frame mem- -bers by the successive placing therein by the workman. Near the outerend of each of said side frame members is an aperture adapted to receive the tongue of a, rigid bridge which over.- lies the outermost solenoid cup in spaced relationship therewith. Said bridge member has any desired plurality of tapped openings which receive set screws or the like, the ends of which bear against the top wall of the outermost solenoid cup. Upon tightening the set screws the respective operating elements are urged one against the other, and in tight relationship with the sub-base which forms the support for the collective operating members. y

The bridge member also aiords means of securing an outer casing and a top closure plate to complete the housing of the device.

The movable contacts are carried by a flexible plate operatively associated with the magnetic armature whereby the movable contacts are resiliently supported in a. manner aiiording self-adjustability with respect to the fixed contacts. 'I'he flexible disc carrying the movable contacts gives under the impact of the movable contacts against the fixed contacts thereby cushioning the same and dampening chatter during the making of the contacts, resulting in improved circuit closing characteristics and enhancing the life of the respective contacts. Y

A feature of our invention is an improved assembly structure for an electromagnetic switch.

A feature of our invention is an improved contact organization for an electromagnetic switch.

Other features and advantages will hereinafter appear. p

Fig. 1 is a sectional view of a preferred form of electromagnetic switch embodying the present invention; l

Fig. 2 is a central sectional view taken on line 2 2 or Fig. 1;

Fig. 3 is a sectional view taken on line 3-3 of Fig. 1; y

Fig. 4 is a sectional view taken I on line 4 4 of Fig. 1;

a,417,4ss

Fig. 5 is another sectional elevation of the device, in closed circuit position, the line of section being onthe line 5-5 of Fig. l;

Fig. 6 is an exploded perspective view of the structure; and

Fig. 7 is a side elevationpartly broken away,

of the assembled structure, with the outer casing broken away to illustrate the positioning of the parts; Fig. 7 also shows a typical wiring diagram.

Referring to the drawings, the housing of our improved electromagnetic switch I0 includes a base plate II, shell I2 and cap I4; these parts are of insulating material. Secured to the base plate II, as by any desired plurality of screws or rivets, is an open frame comprising side pieces I5, I6 within which the operating elements of the electromagneticswitch are contained and secured. As shown in Figs. 1 and 6, each frame member, at a location suitably above the base, has a pair of ears I1, I1 struck inwardly in a common plane; upon said ears rests a plate I8 which serves as a base for the solenoid and snap spring mounting structure, as later described.

. Legs I9 of said base I3 extend downwardly between and in engagement with the side edges of the spaced ears I1, Il of the respective side frame members, and plate I8 is thereby held against rotation without the necessity of welding or like means.

At the center of plate I8 is a square opening, bounded on two opposite sides by downwardly extending guide walls 25, 2U. l

Two arcuate side walls 2l, 2l diametrically placed, extend upwardly from plate I8 to receive and position snap- spring retaining rings 22, 23 and the cup 25 of a solenoid 26, said elements merely being set into position on said base plate I8, without securement thereto. As shown in Fig. 5, ring 22 is shouldered for cooperation with the ring 23 to provide a circular groove within which is confined the rim portion of a snap spring 24.

A second solenoid cup 2l houses a solenoid 28; between the solenoid cups 25 and 2l are a pair of anged spacer members 29, 38, the outer iianges 3l, 32 of which fit snugly /between and in contact with the frame side-pieces I5, I5, and the inner cylindrical anges 33, 34 provide a guide sleeve for a magnetic armature 35, axially slidable therein.

To'eachof the solenoid cups 25, 2l is attached a pole- piece 36, 31, the axial passage of the latter being concentric with respect to the cylindrical flanges 33, 3d, to permit the guided slidable passage of the actuator rod 38, secured to armature 35.

The respective soienoid cups 25 and 21, ring members 29, 38, and pole- pieces 38, 31 are preferably of steel or other magnetic material.

The entire assembly previously described is maintained in proper operative position without individually securingr each of the respective ele` ments by means of a bridge 40 which extends between the side frame pieces I5, I6, to pass through a hole adjacentthe ends thereof, see Figs. 4 and 5. One or more set screws 4|4I, pass through the bridge' 40 to bear against solenoid cup 21, in this manner adjustably holding the respective solenoidpups, cup spacers and snap spring ring members in position against the base plate I8. .Walls 2|, 2| of plate I8 prevent the rings 22, 23, and solenoid cup 25 from shifting laterally, and the side frame members I5, I6, against which the flanges 3l, 32 of sole-l noid cup spacer rings 28, 30 abut, insure that the solenoid cup 21 is held against movement.

The bridge 40 also serves to hold the cap I4 and casing I2 in position, by the screw 42.

Snap spring 24 has an opening through its center'to receive the reduced diameter, threaded, end of the actuatior rod 38, which is secured to a rectangular block 43 of insulation material, the latter passing through the square central opening in plate I8. The walls 20, 20 act as bearing guides for the block 43.

Secured to the other end of the block 43 by means to prevent relative rotation is a preferably at spring 44 which carries, by means of rivits '45, 45, see Fig. 1, a contact bridge 46 having at diametrically spaced locations vcontacts 41, 41, said contacts cooperating with contacts 48, 48 fixed to the insulating base II. Suitable terminal pieces 49 are provided for connection of contacts, 48, 48-into the circuit to be controlled.

'As Fig.` 3 shows, the rivets 45 are at a spacing of 90 with respect to the contacts 41, 41. Such arrangement affords a substantial measure of self-adjustability of contacts 41 with respect to contacts 48, 48, while providing an otherwise rigid-supporting structure for said contacts 41.

Referring to Fig. 7, the respective solenoids 26 and 28 are connected into a common circuit for remote control by a momentary-contact switch S, through the illustratedl terminals on cap I4. The contacts 41, 48 are in the circuit to be controlled. The solenoid coils may or may not be wound for low voltage actuation, according to preference. r

The actuation of solenoid 26 drives the armature to the right as shown in Fig. 5, thereby causing the snap spring 24 to throw into its second position of stable equilibrium as is shown in said figure and bringing the contacts 41 into engagement with the terminal contacts 48. The spring 44 iexes under thev impact of the contacts, acting to dampen the engagement of the said contacts and preventing rebound. Desirably, the engagement of the respective contacts is prior to the attainment of full throw `position of the snap spring, whereupon said snap spring to its reverse position of equilibrium to open the contacts 41, 38. The reaction of spring 44 assists in' the breaking of the contacts at high speeds.

Whereas We have described our invention by reference to specific forms thereof, it will be understood vthat many changes and modiiications may be made provided they do not depart from the scope of the claims We claim:

l. In an electromagnetic switch, the combination of spaced side frame members, a sub-base carried -by and between said side frame members, a snap spring, means for mounting said snap spring disposed upon said sub-base and conned between said side frame members, solenoid means for actuating said snap spring, and means for securing said solenoid means within said side frame members, comprising a bridge member disposed across said side frame members adjacent the ends thereof and means associated with said bridge means and said solenoid means for adjustably maintaining said solenoid means in position with respect to said sub-base.

2. In an electromagnetic switch, the combination of spaced side frame members having ears struck inwardly and in a common plane, a subbase supported on said ears, said sub-base having legs extending inwardly therefrom in engagement with the said ears to hold said sub-base against rotation, solenoid means supported by said sub-base, means including a bridge member extending across said side frame members adjacent the ends thereof, and set screw means passing through said bridge member and bearing against said solenoid means to maintain the position thereof.

3. In an electromagnetic switch, the combinationof a base, side frame members secured to said base in spacedrelationship, a sub-base supported by and between said side frame members in fixed position thereon, snap spring supporting means carried on said sub-base, solenoid means operatively associated with said snap spring means and including cup means, said solenoid cup means being disposed one on the other, and means associated with said solenoid cup means and said side frame means for positioning said solenoid cup means therein.

4. In an electromagnetic switch, the combination of a base, side frame members secured to said base in spaced relationship, a sub-base supported by and between said side frame members in fixed position thereon, snap spring supporting means carried on said sub-base, solenoid means operatively associated with said snap spring means and including cup means, saidsolenoid cup means being disposed one on the other, means associated with said solenoid cup means and said side frame means for positioning said solenoid cup means therein, said means including a member extending across said side frame means adjacent the end thereof, and a screw passing through said member and bearing against the immediately adjacent solenoid cup means.

5. In an electromagnetic switch, the combination of a housing including-a base, side frame members secured to said base and extending upwardly therefrom, a sub-base extending between said .side frame members at a pre-determined xed position and individual solenoid cup members positioned one on the other with respect to said sub-base and means associated with said side frame members and bearing against one of said solenoid cup means to retain said cup means upon said sub-base.

6. In an electromagnetic switch, the combination of a base, spaced side members secured to said base and extending upwardly therefrom, a sub-base positioned between and resting upon elements of said side frame members, snap spring retaining means removably positioned on said sub-base, a rigid solenoid housing disposed between said side frame members and removably positioned upon said snap spring retaining means, a second rigid solenoid housing removably positioned upon the rst-named housing, a bridge member extending between and retained by said side frame members, and means interposed between said bridge means and the last-named solenoid housing to hold the respective solenoid housings and snap spring retaining means in position upon said sub-base.

7. In an electromagnetic switch the combina'- tion of vspaced side frame members, said mem-A bers having extensions projecting inwardly of said members respectively, means for supporting said spaced side frame members including a base, a sub-base supported upon said extensions and disposed intermediate said spaced side frame members, operator means for said circuit breaker and disposed upon said sub-base, bridge means spanning said side frame members and supported by said side frame members, and securing means interposed between said bridge means and said operator means for stably positioning said operator means upon said sub-base.

JOSEPH F. OBRIEN. EARL S. BOYNTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number

Images