US3553616A

US3553616A - Electrical relay

Info

Publication number: US3553616A
Application number: US794136*A
Authority: US
Inventors: John J Rowell; William W Wright
Original assignee: Guardian Electric Manufacturing Co
Current assignee: Guardian Electric Manufacturing Co
Priority date: 1969-01-27
Filing date: 1969-01-27
Publication date: 1971-01-05
Anticipated expiration: 1988-01-05

Abstract

AN ELECTRICAL RELAY HAVING A FIELD PIECE WITH A COIL ASSEMBLY AND AN ARMATURE MOUNTED THEREON INCLUDES A FLAT RETURN SPRING WHICH BIASES THE ARMATURE ABOUT ITS PIVOTAL MOUNTING ON THE FIELD PIECE AND SIMULTANEOUSLY HOLDS THE ARMATURE IN POSITION ON THE FIELD PIECE. ALSO AN IMPROVED SPOOL CONSTRUCTION FOR THE COIL ASSEMBLY INCLUDES A FLANGE ADAPTED TO RECEIVE THE LEAD WIRES OF THE COIL WINDING.

Description

Jam 5, 197,3 J. J. HOWELL v ET AL 395539536 ELECTRICL RELAY A Filed Jan. 27, 1969 2 Sheets-Sheet l ,Hal FV f5.2

05 Vr. 10@ 107108 j: E

'W4 471 100 04 5 e@ 10j 97N@ E w @2 34 62 14 9@ if@ 411/ 2@ g4 Jan 5, QIY 1 RQWELL ET AL 3,553,66

ELECTRICAL RELAY 2 Sheets-Sheet 2 Filed Jan. Q7, 1969 United States Patent O 3,553,616 ELECTRICAL RELAY John J. Rowell, Glenview, and William W. Wright,

Wheaton, lll., assignors to Guardian Electric Manufacturing Company, Chicago, Ill., a corporation oi' Illinois Filed Jan. 27, 1969, Ser. No. 794,136 Int. Cl. H01h 3/54 U.S. Cl. 335-187 1 Claim ABSTRACT OF THE DISCLOSURE An electrical relay having a field piece with a coil assembly and an armature mounted thereon includes a fiat return spring which biases the armature about its pivotal mounting on the field piece and simultaneously holds the armature in position on the field piece. Also an improved spool construction for the coil assembly includes a flange adapted to receive the lead Wires of the coil Winding.

BACKGROUND OF THE INVENTION This invention relates to an improved electrical relay and, in particular, to an electrical relay having an armature connected with a field piece by means of a flat return spring.

A common construction of an electrical relay provides for an armature which is pivotally attached to a field piece. A coil is mounted to magnetically drive the armature in one direction toward the coil Whenever current passes through the coil. The armature is mechanically biased away from the coil by means of a spring, for example, a spiral spring which is attached between the relay housing and the armature. Thus, a contact mounted on the armature moves with the armature to make and break an electrical circuit as the armature is alternatively attracted magnetically by the coil and biased mechanically by the spring.

On relays of the type using a spiral spring to bias the armature, the spring must be suspended at some distance from the armature pivot point to achieve proper mechanical leverage. Thus, valuable volume in the total configuration of the relay is required for the armature biasing spring. Of course, it is very desirable when designing a unit of this type to` provide for maximum performance in a minimum volume. By eliminating the spiral spring and substituting a multi-purpose flat spring, the relay of the present invention minimizes volume requirements without any loss in relay capacity.

Another important consideration in an electrical relay unit is the construction of the electrical coil which magnetically drives the armature. It is important that the spool upon which the coil windings are wound be designed to permit rapid winding, and insure that the wire leads of the windings will not accidentally cross and short circuit. The subject matter of the present invention provides a novel spool construction satisfying these criteria.

Finally, it is desirable to minimize the number of parts in an electrical relay, maximize the performance and load that may be carred by the relay, and minimize the cost and time of assembly of the electrical relay, The present invention provides all of these advantages over prior art relays.

SUMMARY OF THE INVENTION In a principal aspect the present invention is the improvement, in an electrical relay of the type having an armature pivotally mounted on a field piece and a coil assembly for magnetically driving the armature, of a fiat spring for simultaneously holding the armature in communication with the field piece and mechanically biasing the armature outwardly from the magnetic coil assembly. Further, the coil preferably includes a peripheral recess about a flange of the spool upon which the coil windings are wound so that the two leads from the coil are separated from one another and protected from abrasion and short circuiting.

It is thus an object of the present invention to provide an improved electrical relay which minimizes unit volume by providing a flat spring for mechanically driving the armature.

Another object of the present invention is to provide an improved electrical relay which utilizes a flat spring to hold the armature on the field piece and simultaneously mechanically biases the armature outwardly from the coil assembly.

It is a further object of the present invention to provide an improved electrical relay comprised of a minimum number of component parts occupying a minimum volurne.

It is still another object of the present invention to provide an improved electrical relay which is easy to assemble and economic to manufacture.

One further object of the present invention is to provide an improved electrical relay having an improved coil construction which provides improved protection to the wire leads of the electrical coil.

These and other objects, advantages and features of the present invention will be set forth in greater detail in the description which follows:

BRIEF DESCRIPTION OF THE DRAWING In the detailed description which follows reference will be made to the drawing comprised of the following figures:

FIG. l is a side View of the improved electrical relay of the present invention;

FIG. 2 is an end view of the relay shown in FIG. l and ilustrates the contact lug configuration for the relay;

FIG. 3 is a top plan view of the relay shown in FIG. l;

FIG, 4 is a cross sectional view of the relay shown in FIG. l taken substantially along the line 4 4;

FIG. 5 is an enlarged cross sectional view of the lugs shown in FIG. 2 taken substantially along the line 5 5;

FIG. 6 is a top cross sectional view of the lugs shown in FIG. 5 taken substantially along the line 6 6;

FIG. 7 is an enlarged top plan View of the relay illustrating the relationship of the flat sprng and the armature;

FIG. 8 is a cross sectional view of the armature assembly taken substantially along the line 8 8 in FIG. 7;

FIG. 9 is a side view of the spool for electrical windings in the coil assembly of the relay;

FIG. 10 is a left hand end view of the spool in FIG. 9;

FIG. 11 is a right hand end view of the spool in FIG. 9;

FIG. 12 is a side elevation of the at armature return spring used in the relay;

FIG. 13 is an end view of the spring in FIG. 12; and

FIG. 14 is a top view of the spring in FIG. 12.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1, 3 and 4 there is shown the construction of a relay incorporating the features of the present invention. The relay includes a field piece 10 which is rigidly attached to a terminal block 12 by means of a threaded bolt 14 extending from the field piece 10` and passing through an opening in the terminal block 12. The terminal block 12 is preferably fabricated from an insulating material such as alkyd or diallylthalate. The field piece 10 is preferably fabricated from metal such as a magnetic iron. A nut 16 secures the field piece 10 against the terminal block 12. A clear plastic relay cover 18 encloses the entire relay assembly.

The field piece includes an armature mounting member 20 and a coil assembly mounting member 22. An armature assembly 24 and a coil assembly 26 are attached to the mounting members 20 and 22 respectively.

The coil assembly, as illustrated in FIGS. l and 4, includes a molded plastic spool 28. The spool 28 illustrated in FIGS. 9-1l, includes a bottom fiange 30, a top flange 32 and an interconnecting core section 34. The spool 28 preferably is molded from a polycarbonate resin, a nonconductive material. The core section 34 is cylindrically shaped and adapted to receive coil windings about its outer surface. The wound coil is preferably covered by insulating tape 33 as shown in FIG. l. The coil windings may be wrapped around the core section 34 in either the clockwise or counterclockwise direction.

Positioned on the inside of the core section 34 is a magnetic metal core 36 as illustrated in FIG. 4. The core 36 passes through the core section 34 and is fastened to the coil assembly mounting member 22. Spool 28 is mounted on the core 36. A shading ring 38, fabricated of copper, cooperates with the core 36 to hold the spool 28 in position. The shading ring 38 is positioned in a shaped depression 40 in the top fiange 32.

Top flange 32 also includes a pair of grooves or recesses 41 and 42 around the outer periphery of the top flange 32. The

recesses

41 and 42 are smooth surfaced, continuous grooves having no sharp corners which might sever or cut lead wires and 52 from the coil. Recess 41 is the start side recessand receives the starting lead 50 of a wire Winding. Recess 42 is the finish side recess and receives the finish end lead of a winding.

The

recesses

41 and 42 terminate at a slot 44 defined in the bottom portion 33 of the top flange 32 as illustrated in FIG. 11. Slot 44 is dimensionally wider than the sums of the diameters of lead wires, 50 and 52 in FIG. 4. This insures that lead wires will not cross or short the coil. Start side recess 41 forms an acute angle with one side of slot 44 whereas finish side recess 42 substantially coincides with the opposite side of recess 44. This further insures that the lead wires will not cross or short circuit.

In addition, the top flange 32 of the spool 28 has a pair of integrally molded

lead wire ears

46 and 48. The lead wires 50 and 52 from the coil are twisted around the

ears

46 and 48, respectively. Thus, ear 46 receives the start side lead lwire 50 of a coil winding. Ear 48 then receives the nish side lead wire 52 of a coil. Each lead wire 50 and 52 is connected to an appropriate

coil control lug

87 and 88 respectively. This construction and arrangement of the recesses in the top fiange 32 along with the

ears

46 and 48 pro-vides for greatly improved ease of Winding and manufacture and results in savings due to acceleration of manufacture and assembly of the relay.

Referring now to FIGS. l-S, the armature assembly 24 is attached to the armature mounting member 20 of the field piece 10. The assembly 24 includes 4 contact blades 54 through 57 which are molded in a block 58. Because the blades 54-57 are molded in position, proper alignment of contacts mounted on the blades with contacts on the various lugs in terminal block 12 is assured. The block 58 is rigidly attached to an armature 60. The block 58 is fabricated from an insulating material so that the armature 60 and blades 54 through 57 are electrically insulated from one another.

The armature 60 is pivotally mounted on the mounting member 20 and held in position on the mounting member 20 by means of a flat spring 62. Mounting member 20 includes first and second projections 64 and 66 which extend outwardly from mounting member20 and loosely fit through openings or recesses 68 and 70 defined in the armature 60. A flat blade or bushing 71 is inserted between the armature 60 and mounting member 20 in the area between the projections 64 and 66.

As illustrated in FIGS. 1214, flat spring 62 includes a field piece end 72 and an armature end 74. Field piece end 72 is shaped to fit through an opening 76 in the mounting member 20 as shown in FIGS. l or 4. The majority of the length of the field piece end 72 is positioned on the side of the field piece opposite the coil assembly 26; whereas, the extremity of the field piece end 72 is shaped to fit `through the opening 76 and against the side of the field piece adjacent the coil assembly 26. The flat spring 62 also includes in the field piece end 72` a tab 78 which cooperates With one side of the opening 76 to facilitate holding the spring 62 in tight communication with the member 20.

The armature end 74 of the spring 62 fits through a slot 80 in the block 58 as shown in FIGS. l, 3 and 8. The spring 62 is slidably received by the slot 80; however, a tab 82 in the armature end 74 lockingly engages the block 58 following insertion through the slot 80 and cooperates with the spring extensions or wings 84 and 85 on the opposite side of the lblock 58. Thus, the fiat spring 62 is held in a fixed position in relation to the armature assembly 24.

The `flat spring 62 is biased to drive the blades 54 through 57 in a counterclockwise direction about the pivot point defined by the armature 60 and field piece 20. Thus, the flat spring 62 drives contacts on the blades 54-57 into a closed circuit position with contacts on lugs 105-108. Simultaneously, since the flat spring 62 is locked in contact with the armature 60 and field piece 20, it serves to hold the armature 60 in position relative to the field piece 20. In FIG. l2, the phantom lines indicate the free position of the spring 62 and the solid lines indicate the assembled position. The spring 62 provides a uniform back tension to the armature 60.

To move the armature 60 by electric signal means, current is introduced through the coil assembly 26. This, in turn, causes a magnetic attraction of the armature 60l to the core 36 thereby depressing the blades 54 through 57 in a clockwise direction about the axis of rotation of the armature 60 and the field piece 20. As shown in FIG. 2 the coil assembly 26 is activated whenever current is introduced through control coil lugs 87 and 88.

Current input through armature connected lugs 94 through 97 passes through lead wires 114-117 respectively, then through the blades 54 through '57 respectively, the contacts on the ends of the blades 54 through 57 and finally through a set of output lugs 101 through 104 or 105 through 108. Thus, when the coil is not activated contacts as at 98 on blade 57 connect with output contacts as at 99 on lug 105. When the coil is activated and the armature 60 is depressed the double-headed contact 98 makes a junction with the contact 100 attached to lug 104.

IFIGS. 5 and 6 provide an enlarged view of the connection of the lugs to the terminal block 12. As can be seen in these figures the

lugs

104 and 105 include formed tabs as at on lug 105 which cooperate with recesses in the terminal block and with a bent tab as at 91 on lug 105 to hold the lug 105 in position in the terminal block 12. In this manner the lugs can be precisely positioned in the terminal block and better serve to hold the contacts on the ends of the lugs in an affixed, rigid position. Thus, proper intersection of the contacts on the ends of the blades 54 through 57 is assured with contacts on the lugs 101-104 or 105-108.

What is claimed is:

1. In an electrical relay of the type having a field piece, a magnetic coil assembly in fixed relation with said field piece, an armature pivotally mounted on said field piece and held from longitudinal movement by lugs extending from said field piece through recesses in said armature at the pivotally mounted position of said armature on said field piece, said armature magnetically responsive to said coil assembly, said armature drivingly connected with at least one contact so as to drive said contact against second contact means to make and break a circuit whenever said coil assembly acts to induce motion to said armature,

said armature normally being biased away from said coil through said opening in said field piece and engaging assembly about the pivotal mounting of said armature the inside of said field piece adjacent said coil to with said field piece, the improvement of: hold said field piece leg against said field piece.

a single, flat, removable, return spring for simultaneously holding said armature in said pivotally 5 References Cited mounted position against said field piece and mechanically biasing said armature away from said coil UNITED STATES PATENTS assembly in a direction opposite said induced motion, 2,856,492 10/ 1958 Heyhal 200-166(ICTS) said return spring including an armature leg and a 2,916,580 1'2/1959 Seele 335 1g7 yfield piece leg, said armature including a Contact 10 3,023,286 2/1962 Bourne 335 187 mounting block with a slot therethrough extending 3,051,804 g/1962 Mayer 335 1g7 toward said pivotally mounted position for receiving 3,054,871 9/ 1962 Skay 200-166(\ICTS) said armature leg of said return spring, said armature 3,035,139 4/1963 Wright 200l66(I\CTS) leg including at least one tab and one wing which 3,230,489 1/1966 Weyrich 336 192 engage said mounting block on opposite sides thereof 15 3,308,407 3/1957 Lake 33 5 187 to hold said armature leg in fixed relation with said mounting block, said field piece including an open- HAROLD BROOME, Primary Examiner ing therethrough, said field piece leg positioned against said field piece on the side opposite said coil U.S. Cl. X.R. assembly and including an extremity tab passing 20 200--166