US2845585A - Encapsulated relay - Google Patents

Description

July 29, 1958 R. L. VICENZI ETAL ENCAPSULATED RELAY Filed April 12, 1957 n m m N WE WKD n w M L n O A m 5. Y B

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United States Patent Office Patented July 29, 1958 ENCAPSULATED RELAY Reno L. Vicenzi and Ferdinand F. Heiser, Milwaukee, Wis., assignors to Controls Company of America, Schiller Park, III., a corporation of Delaware Application April 12, 1957, Serial No. 652,428 Claims. (Cl. 317-165) This invention relates to a relay having an encapsulated electromagnet. More particularly, this invention relates to a relay mounted in a housing which has a well in which the coil (electromagnet) is encapsulated to seal the coil and permanently fix the coil in the housing.

It is well known that it is desirable to encapsulate coils and the like to gain the advantage of encapsulation over varnish impregnation and the like. In the present instance it appeared desirable to encapsulate the electromagnet right in the relay housing in order to use the housing for a mold and to also seal the electromagnet in place. This obviously calls for placing the coil in a well or the like. With the present relay it is desirable from various views to employ a tension spring to bias the armature and the most convenient and practical location for the spring anchor is below the level to which the encapsulating material will rise in the well. Various efforts to prevent the material from approaching the biasing spring ran into too high production cost and lessthan-perfect results. The present simple arrangement seals the spring and the material can now be' poured around the spring with no danger of leakage onto the spring. The structure is simple and permits reduction of production costs.

The object of this invention, therefore, is to provide an encapsulated relay electromagnet and spring assembly which is simple and inexpensive to manufacture while insuring proper spring operation.

Another object is to provide an improved method of making a relay electromagnet and spring assembly having the above stated characteristics.

Other objects and advantages will be pointed out in, or be apparent from the specification and claims, as will obvious modifications of the single embodiment shown in the drawings, in which:

Fig. 1 is a top plan view of a relay operated valve embodying the invention with the valve seat plate removed;

Fig. 2 is a cross-section taken along line 2-2 of Fig. 1 with the valve seat plate in assembled position; and

Fig. 3 is a fragmentary sectional view taken along line 3-3 of Fig. 1.

Referring to the drawings in detail, the relay is housed in casing 10 having partition 12 extending transversely across the casing at a height somewhat less than the height of the side walls of the casing and forming two chambers or wells 14, 15 with the walls of casing 10. Electromagnet 16, comprising coil 18 and core 20, is mounted on horizontal arm 22 of an L-shaped frame 24 in well 14. Armature 26 is pivotally mounted on the upper edge 27 0f the vertical portion 28 of frame 24. Notches 29 in opposite edges of the armature receive ears 30 extending upwardly from the frame. Each end of coil spring 32 is hooked, as at 33, to connect the spring to armature 26 through hole 35 and to lug 34 projecting from frame 24 to bias armature 26 away from core of electromagnet 16.

Frame 24 and, electromagnet 16 are mounted in well 14 with spring 32 attached before encapsulation. No

matter how the frame was formed in an effort to have it act as a dam, some leakage to the space around the spring occurred before the resin set. This both fouled the spring and dropped the level around the coil. Therefore, the frame is now made so leakage will definitely occur and steps are taken to prevent the resin or en capsulating material 37 from contacting the spring. Bearing in mind the leakage problem plus space limitations, it will be appreciated the spring must be attached prior to encapsulation.

Spring 32 is mounted in a cylindrical shell or jacket 36 of metal or other suitable material having an opening 38 at its upper end to allow connection of spring 32 to armature 26, and an opening 40 of smaller diameter at the lower end forming a shoulder 42. An elastic sealing member 44 (sponge rubber, for example) of slightly greater diameter than the inside of jacket 36 rests on shoulder 42 and has a slit in the central portion thereof through which one terminal hook 33 of spring 32 passes for connection to lug 34 projecting from frame 24. In order to hook the spring on the lug the seal 44 must be compressed slightly to positively seal-off the bottom opening and prevent entry of resin during encapsulation. Spring 32 is protected from fouling by the encapsulating material by jacket 36 which extends above the level of the encapsulating material.

The encapsulated relay described above is shown actuating a valve 50 mounted on follower arm 52 which is anchored at one end by engagement of its offset ears 57 in openings 58 in armature 26. A lost motion connection is provided between armature 26 and arm 52 by tongue 66 on the end of the armature extending through a slot 61 in the vertical portion 62 of follower arm 52. Ears 57 are held in openings 58 by leaf spring 59 fastened to the end of armature 26 by rivets 63 and bearing against the boss on the arm. As shown in Fig. 2, the valve 50 seats against seat 64 formed on a valve seat plate 66. The valve seat plate is mounted on the top of casing 10.

While of no great importance, so'far as the invention is concerned, the relay operates the valve as follows. When the coil is energized the armature starts moving toward the core and the valve remains closed during the initial movement. This deflects leaf spring 59 until the armature tongue 60 strikes the end of the slot 61 and transfers its now considerable energy to the follower arm 52. At this time the leaf spring 59 restores its energy to the system to aid in snapping the valve open. The same relay can be used to actuate a normally open valve, a switch or other mechanisms.

A brief rsum of the assembly is in order. One end of spring 32 is poked through the sponge rubber seal 44 and the spring is then pushed into the jacket 36 until the sealed end of the spring projects through the bottom opening and can be connected to anchor lug 34. The electromagnet, frame and spring are now placed in the well 14 for encapsulation. After the resin 37 has hardened the armature is mounted and a hooked tool is used to pick up the end of the spring for connection to the armature. This method and structure are extremely simple and have resulted in lower production costs. An extra bonus realized is that the resin now positively captures the lower end of the spring and there is no longer any difficulty with the spring coming loose.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

We claim:

1. A encapsulated relay comprising, a housing with a Well formed therein, a mass of insulating encapsulating material in said well, an electromagnet including a coil and a core in said encapsulating material, a movable armature pivotally mounted opposite the core of said electromagnet for attraction thereby when said coil is energized, a spring mounted in'said encapsulating material with one end connected to said armature and the other end anchored in said Well, and enclosure means for said spring to prevent said encapsulating material from contacting the spring.

2. An encapsulated relay according to claim 1 in which said enclosure means includes a sleeve-like jacket around said spring, said jacket having an opening in one end thereof to allow connection of said spring to said armature.

3. An encapsulated relay according to claim 2 in which said enclosure means further includes an opening in said other end of said jacket, and sealing means in said opening in said other end of said jacket to prevent said encapsulating material from entering said jacket and through which said spring extends for anchoring in said well.

4. An encapsulated relay according to claim 3 in which said sealing means comprises an elastic member with a slit in the central portion thereof through which said spring extends.

5. An encapsulated relay according to claim 4 in which said other end has a shoulder adjacent the opening therein and serving as a seat for the sealing member.

6. An encapsulated relay comprising, a housing having a well therein, a mass of insulating encapsulating material in said Well, a frame member mounted in said encapsulating material, an electromagnet including a coil and a core mounted in said encapsulating material and fastened to said frame member, a movable armature pivotally mounted opposite the core of said electromagnet for attraction thereby when said coil is energized, a spring mounted in said encapsulating material with one end connected to said armature and with the other end anchored in said well, and enclosure means for said spring to prevent said encapsulating material from fouling said spring.

7. An encapsulated relay according to claim 6 in which said enclosure means includes a sleeve-like jacket around said spring.

8. An encapsulated relay according to claim 7 in which said jacket has an opening in the end adjacent the anchor in the well, and a seal in said opening to prevent said encapsulating material from entering said jacket, said spring extending through said seal and being connected to said frame member.

9. An encapsulated relay according to claim 8 in which said seal comprises an elastic member with a slit in the central portion thereof through which said spring extends.

10. An encapsulated relay according to claim 9 in which said jacket has a shoulder adjacent said opening serving as a seat for said elastic member.

References Cited in the file of this patent UNITED STATES PATENTS

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