US3289697A

US3289697A - Solenoid valve having the solenoid encapsulated within a dielectric cover

Info

Publication number: US3289697A
Authority: US
Inventors: James A Kozel; Plasko Emil Robert; Henry W Kogan
Original assignee: American Radiator and Standard Sanitary Corp
Current assignee: American Radiator and Standard Sanitary Corp
Priority date: 1964-01-09
Filing date: 1964-01-09
Publication date: 1966-12-06
Anticipated expiration: 1983-12-06

Description

1966 J. A, KOZEL ETAL 3,289,697

SOLENOID VALVE HAVING THE SOLENOID ENCAPSULATED WITHIN A DIELECTRIC COVER Filed Jan. 9, 1964 INVENTORS JAIME! 4L K0254 United States Patent Office 3,289,697 Patented Dec. 6, 1966 3,289,697 SOLENOID VALVE HAVING THE SOLENOID EN- CAPSULATED WITHIN A DIELECTRIC COVER James A. Kozel, Franklin, Emil Robert Plasko, Walled Lake, and Henry W. Kogan, Oak Park, Mich., assignors to American Radiator & Standard Sanitary Corporation, New York, N.Y., a corporation of Delaware Filed Jan. 9, 1964, Ser. No. 336,685 3 Claims. (Cl. 137-606) This invention relates to solenoid valves, as for example solenoid-operated mixing valves used in supplying water of selected temperatures to domestic clothes washing machines. I a

One object of the invention is to provide a solenoid valve in which the electrical coil is encapsulated within a molded dielectric cover.

Another object is to provide a solenoid valve having novel means for diffusing the magnetic flux, where-by to achieve a relatively low cost coil.

An additional object of the invention is to provide a pilot-operated valve wherein the pilot element operates against a fixed pilot port, whereby the pilot element can have a fairly short travel without interferring with movement of the main valve element.

A further object is to provide a solenoid-operated mixing valve wherein two solenoid coils are energized by only three terminals, whereby to permit economies in the lead-in wiring.

A general object is to provide a pilot-operated mixing valve which can be manufactured as a relatively compact low cost device.

In the drawings:

FIGURE 1 is a top plan view of one embodiment of the invention;

FIG. 2 is an enlarged sectional view taken taken substantially on line 2-2 in FIG. 1;

FIG. 3 is a sectional view taken substantially on line 33 in FIG. 2; and

FIG. 4 is a sectional view taken substantially on line 4-.4 in FIG. 2.

In the drawings numeral refers to a pilot-operated mixing valve having a valve body 12 and a molded dielectric cover element 14 secured thereon by three screws 16. Body 12 is contoured to provide a tubular inlet 18 for fluid of one temperature, a tubular inlet 20 for fluid of another temperature, and a tubular outlet 22. As shown in FIG. 2, inlet 18 supplies fluid to an annular inlet chamber 24 which is concentric with an outlet chamber 26. Flow of fluid from chamber 24 into chamber 26 is controlled by a rubber diaphragm 28. Chamber 26 then directs the fluid into a horizontal discharge duct 30 which extends within tubular outlet 22.

Diaphragm 28 is positioned within a recess in cover 14, whereby to cooperate therewith in defining a pressure chamber 25. Additional recesses in the cover provide an exhaust chamber 27 and a connector channel 23. As shown in FIG. 2, chamber 27 accommodates an enlarged disc-type valve element 31 which cooperates with a guided plunger 35 to form an armature designated generally by numeral 33. When electric coil 32 is energized armature 33 is drawn upwardly to open a pilot port 34 formed in the fixed rubber element 36. Port 34 overlies the end portion of a pilot channel 37 which connects with duct 30.

When port 34 is open, fluid can flow from inlet chamber 24 through bleed port 29, channel 23, chamber 27, port 34, channel 37, and duct 30. The pressure differential between the fliud in chambers 24 and 25 is thus enabled to bias diaphragm 28 upwardly to permit the main body of fluid to flow from chamber 24 through i which controls the fluid flowing from inlet 20 to outlet 22.

Inlet 18 may be connected with the source of hot fluid, and inlet 20 may be connected with the source of cold fluid, or vice versa. The electric coils may be energized singly or collectively to provide the desired flows. Pref- 1 erably the

duplicate rubber parts

36, 28, 36a and 28a are formed as an integral one piece element. To provide an adequate seal between the various chambers the integral rubber element may be provided with upstanding

periph eral ribs

19, 21, 19a and 21a fitting within mating grooves in cover 14.

As shown in FIG. 2, illustrated electric coil 32 is wound on a spool 46 which has an upper end flange 39 and a lower end flange 38. The lower end flange is provided with two slots which grippingly receive the pronglike end portions of spade-type terminals 40 and 42. The terminals may be connected with the ends of the coil wires in any suitable manner. However for illustration purposes we have shown the inner end wire of coil 32 extending through a slot 44 in spool flange 38% and thence wrapped about terminal 40, as at 48. The outermost wire of the coil may be drawn under the lower surface of flange 38 and thence wrapped about terminal 42, as at 52. Solder may be applied to the wrapped

portions

48 and 52 to provide good electrical connections. Similar wrapping and soldering operations may be utilized for the wire of coil 32a.

Preferably, although not necessarily, only three of the tour illustrated terminals are directly accessible to the lead-in wiring. Terminal 42 is therefore shortened and is connected with terminal 421: by a bridging; portion 43. The one piece element formed by

portions

42, 43 and 42a thus constitutes a single common terminal which is connected with an end wire of each coil. In the illustrated arrangement this common terminal connects with.the wire ends which extend from the outermost windings of the coils, although the common terminal could be connected with the wires which extend from the innermost windings of the coils. If desired, the

wire portions

52 and 52a could be wrapped about a common area of the terminal; in this case terminal 42 and bridge 43 could be eliminated.

The use of three terminals for the two coils is not particularly advantageous in reducing the cost of the solenoid valve, but it is advantageous in permitting some cost reduction for the lead-in wiring. The two coils can be electrically energized from a single three-wire cable which is less costly than two separate two-wire cables necessary under prior art practice. Preferably the lead-in wiring is connected with

terminals

40, 42a and 40a by means of a female plug having :an electrical clamp portion adapted to register with each of the projecting terminal portions. As shown in FIG. 3, the terminals are non-symmetrical so that the female plug must be inserted onto the terminals in the correct electrical position.

Each electrical coil 32 or 32:: is encapsulated within the molded dielectric material for cover 14. Preferred material for both the cover and spool is epoxy. During the handling and molding operations it may be advantageous to have the two spools 46 and 46a connected together as a unitary assembly. For this purpose one or both of the

spool flanges

38 and 39, and 38a and 39a, may have cooperating snap-on connector portions formed thereon. As shown in FIG. 3, the snap-on portions comprise semi-resilient male fingers 54 on spool flange 38 and a companion slot or recess 56 in spool flange 38.

As shown in FIG. 2, the spool 46 for coil 32 has inserted therein a pole piece or magnetic core which comprises a post portion 58 and an enlarged head portion 60. Similarly, armature 33 comprises a movable post or plunger portion 35 and an enlarged head portion 31. The employment of armature and core elements having enlarged head portions has been found to considerably improve the performance of the solenoid, particularly as regards reduction in the amount of copper going into the coil. It is believed that the enlarged head portions have the function of diffusing the flux, whereby to prevent flux concentrations at the ends of the coil. The flux apparently is radiated from the enlarged head portions with comparatively small reluctance (i.e., compared to an arrangement not having the enlarged head portions). There is of course a relatively long axial gap between the circumferential edge areas of the two enlarged head portions 60 and 31. However the relatively large surface areas of these portions provides a large total effective cross sectional area for the return flux so that the effective reluctance of the magnetic circuit is satisfactorily small. The coil design is therefore suited to the use of relatively small amounts of copper wire in the windmg.

A further factor contributing to reduction in copper is the fact that pilot valve portion 31 operates against a fixed port located remote from element 28. Main valve element 28 can have an extensive travel in accordance with the main flow requirements, and pilot element 31 can have a lesser travel sufiicient to bleed chambers 25 and 27 through orifice 34. The small pilot element travel can be provided by a relatively small coil having a small mass of copper.

The primary features of this invention are believed to reside in the concept of encapsulating the coil or coils in a dielectric cover, the employment of three accessible terminals to service two coils, the use of a pilot element operating against a fixed orifice, and the use of core and armature members having enlarged magnetic head portions located at opposite ends of the coil. Some variation in detail from that shown in the drawings is believed possible while still following the teachings of the invention.

What is claimed is:

1. In a mixing valve having a pair of individually energizable solenoid coils arranged in side-by-side relation for controlling the flow of fluids through the valve: the improvement comprising a spool for each coil; a first terminal mounted one one spool in electrical connection with one end of the coil carried thereon; a second terminal mounted on the other spool in electrical connection with one end of the coil carried thereon; a third terminal mounted jointly on both spools is electrical connection with the other end of each coil; and a single continuous molded dielectric cover material encapsulating both coils and their spools; said terminals being located closely adjacent one another for connection with the wires of a three wire power supply cable.

2. A mixing valve comprising a valve body having a face configured to form a pair of fixed main ports and fixed pilot ports adjacent thereto; a pair of spools arranged in side-by-side relation and individually registering with each pilot port; an electrical coil wound on each spool; a magnetic core for each coil including a post portion disposed within one end of the spool and an enlarged head portion overlying said one spool end; a movable armature for each coil including a plunger disposed within the respective spool, and an enlarged head portion disposed between the spool and the registering pilot port; a continuous molded dielectric cover seated on the aforementioned valve body face and encapsulating both coils; and three terminals extending within and Without the encapsulating material; one of said terminals being mounted on one spool in electrical connection with one end of the coil carried thereon; another of said terminals being mounted on the other spool in electrical connection with one end of the coil carried thereon; and the remaining terminal being mounted jointly on both spools in electrical connection with the other end of each coil.

3. A valve' comprising a valve body having a face thereof configured to form concentric inlet and outlet chambers separated by an annular main valve seat; said valve body having an outlet chamber in fluid communication with said valve seat to receive liquid therefrom; a one piece combination gasket-diaphragm valve element of elastomeric material disposed on said one face of the valve body; said elastomeric element having its diaphragm portion overlying the main annular valve seat to move toward and away therefrom; a molded dielectric cover having a face thereof overlying said element; means retaining said cover, elastomeric element, and valve body together in liquid-tight relation; said cover having a recess in the aforementioned face; said recess being configured to define a cavity accommodating movement of the diaphragm portion away from the main valve seat, and a pilot valve element chamber communicating with said cavity to receive liquid therefrom; a solenoid encapsulated within the cover, said solenoid comprising a dielectric spool having a hollow tubular portion defining an interior extension of the valve element chamber, an electrical winding wound about said tubular portion and sealed within the cover; a pole piece for the solenoid comprising an enlarged magnetic head portion overlying the end of the spool remote from the valve element chamber, and a post portion extending into the hollow space defined by the tubular portion; said elastomeric element-having a pilot port extending therethrough in direct alignment with the interior extension of the valve element chamber; a pilot valve element comprising a magnetic armature plunger having a portion thereof slidably disposed within the chamber extension in direct guided engagement with the spool interior surface; passage means for conveying pilot liquid from the inlet chamber to the aforementioned cavity; and second passage means for conveying pilot liquid from the pilot port to the outlet chamber.

References Cited by the Examiner UNITED STATES PATENTS WILLIAM F ODEA, Primary Examiner.

ISADOR WEIL, Examiner.

D. LAM ERT, ss stant Examine

Claims

1. IN A MIXING VALVE HAVING A PAIR OF INDIVIDUALLY ENERGIZABLE SOLENOID COILS ARRANGED IN SIDE-BY-SIDE RELATION FOR CONTROLLING THE FLOW OF FLUIDS THROUGH THE VALVE; THE IMPROVEMENT COMPRISING A SPOOL FOR EACH COIL; A FIRST TERMINAL MOUNTED ONE ONE SPOOL IN ELECTRICAL CONNECTION WITH ONE END OF THE COIL CARRIED THEREON; A SECOND TERMINAL MOUNTED ON THE OTHER SPOOL IN ELECTRICAL CONNECTION WITH ONE END OF THE COIL CARRIED THEREON; A THIRD TERMINAL MOUNTED JOINTLY ON BOTH SPOOLS IS ELECTRICAL