US2562439A - Plunger guide for solenoids - Google Patents

Description

y 1951 RSCHELL 2,562,439

PLUNGER GUIDE' FOR SOLENOIDS Filed Nov. 6, 1948 54 92 INVENTOR.

P414 pmezi.

Patented July 31, 1951 PLUNGER GUIDE FOR SOLENOIDS Pall Iowa

Sehell, Elkhart, Ind., alllgnor to Penn Electrie Switch 60., Goshen, Ind., a corporation of Application November 6, 1948, Serial No. 58.639

This invention relates to a guide for the plunger of a solenoid. the guide being removably positioned in relation to the core for the solenoid coil whereby the coil may be pre-wound and then inserted in the core after which the guides are positioned inside the coil and the coil with its core and guides are then ready to receive the plunger. I

One object of the invention is to provide an arrangement which permits the plunger guides to be removably positioned in relation to the solenoid core so that coils can be interchanged if desired and the initial assembly of the entire solenoid facilitated by an arrangement which permits the coil to be pro-wound independent of the core and then inserted in the core after it is wound, the association of the guides with the core being such as to permit rigid mounting of the guides in the core yet also permit them to be later removed without the necessity of removing any fastening elements.

Another object is to provide a solenoid core with a frame designed to coact with plunger uides in such manner that the guides are received in the frame at one end and are provided with hook-like fingers to coact with the frame at the other end so that both ends are fixed in supported position.

A further object is to provide a spring finger projecting from the plunger guide for coaction with the core frame to retain the guide in position except when the finger is depressed to permit removal of the guide.

With these and other objects in view, my invention consists in the construction, arrangement and combination of the various parts of my device whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claim and illustrated in the accompanying drawings, wherein:

Figure 1 is a front elevation of a motor starter switch showing my invention in connection therewith. v

Figure-2 is a plan view of the solenoid and its plunger and. guides apart from the motor start- 1m switch.

Figure 3 is a sectional view on the line 3-3 of Figure 1.

Figure 4 is a perspective view of one of the plunger guides.

Figure 5 is an inside elevation thereof, and

Figure 6 is a perspective view oi the solenoid core and the core frame showing one 00f the plunger guides in position for assembly in relation thereto.

On the accompanying drawing, I have used the reference character MS to indicate in general a motor starting switch as shown in my copending application, Serial No. 695,336, filed September 6, 1946, now abandoned. The motor starting switch has stationary contacts Ill and movable contacts II. The contacts l2 are carried by a block of insulation l4 adapted to be connected with the plunger of the solenoid. Suitable brackets it connect with the motor starting switch MS and with a back plate It.

The solenoid here involved comprises a coil II, a rectangular core 20 formed of laminae and a a plunger 22 also laminated, in addition to the plunger guides which will be described specifically. The core 20 as illustrated in Figure 6 is not a complete rectangle but open at one end to receive the plunger I! as in Figure 3, the plunger being normally in the lowered position illustrated and adapted to be raised by magnetic attraction when the coil is is energized until the upper end oi. the plunger strikes the upper leg of the core 20 in the usual manner.

The core laminae 20 are stacked between a pair of similar frame plates 22, the assembly being riveted together as at 24. Openings 26 extend through both core plates 22 and the laminae 20 to receive mounting screws 20 which mount the core on the base plate l'l.

Each core plate 22 is rectangular in shape and has an outwardly oifset plunger guide receiving portion 30 at one end and a, similar guide receiving portion 32 at the other end. The portion 32 is notched as illustrated at 34.

The plunger guides are shown best in Figures 4, 5 and 6. They hear the reference character G. Each guide is channel shaped in cross section having a web 36 and flanges 38. The flanges it are cut back or notched at 40 at one end and at 42 at the other end. The end at 42 has a reverse bent lip 44 and adjacent the lip a spring finger it is bent slightly out of the plane of the web It.

Adjacent the other end of the guide a pair of beads 48 and a projection 50 are provided for defining a guide channel for the plunger and properly guiding it without undue friction along the entire surface of the guide G. The guides G are inserted through the guide receiving portions 32 and 30 successively as suggested in Figure 6 and as illustrated in Figure 3. In Figure 3 the right hand guide is in its final position, whereas the leit hand guide is being inserted to its final position. In such final position the notches ii engage inthe guide receiving portion II and it will be noted in Figure 4 that the long side of the notch is at a slight angle which serves to guide the entering'end of the guide G into the portion II and tighten it therein.

In the final position of the guide as at the right side of Figure 3, the lip 44 engages the guide receiving portion 32 oi" the core frame to securely position this end of the guide G. The lip 44 is at this time under slight spring tension and as soon as the lower end of the finger 4! passes the portion 32 it will snap from the position at the left side of Figure 3 to the position at the right side thereof and thereafter keep the guide G permanently in its mounted position.

The guide however can be removed by pressing the finger ll inwardly to clear the portion 32 as when necessary for dis-assembling the solenoid for changing the coil thereof.

With the arrangement disclosed the core and frame assembly 2022 shown in Figure l is adapted to receive the solenoid coil it after the coil has been pre-wound on a form in a winding machine. It is unnecessary to wind the coil in position in the core as it can be merely placed in the core of Figure 6 before the plunger guides G are inserted.

After the guides are inserted to their assembled position the plunger I1 is slid into position in the guides and the side plates i which are riveted to the laminated plunger are guided by the channel shaped guides G with the beads 49 and the projection 50 serving as the guiding points at the upper end of the plunger. The side plates II are then connected to the contact block I! as by a screw 52 and in the down position of the plunger the block engages the upper surface of the upper leg of the core 2| to act as a stop. A cross piece it on the lower end of the plunger acts as a means to aid in carrying the flux across the air gaps between the plunger and the core. Engagement of the plunger with the lower surface of the upper leg of the core is the means to tor starting switch or with any element to be operated by the plunger.

The guides are mounted so that they can be readily removed if that is desirable as for instance when replacing a bumed-out coil or changing coils. The arrangement also makes possible the assembly of the solenoid in a minimum of time.

Some changes may be made in the construction and arrangement of the parts of my device without departing from the real spirit and pur pose of my invention, and it is my intention to cover by my claim any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

I claim as my invention:

In a solenoid construction, a core. frame plates connected on opposite sides thereof and provided with guide receiving portions, channel-shaped plunger guides removably received in said portions, one of said guide receiving portions defining a passageway to receive one end of a guide and said end having its flanges partially cut away at an angle to produce a wedging action of said plunger guide in said guide receiving portion, said guides having return bent convergent lips at their other ends. the other of said guide receiving portions being received in said return bent lips and resiliently confined between them and the opposing surfaces of said guides. said guides having U-shaped slots to provide locking tongues comprising those portions of the guides between the legs of the U-shaped slots. said locking tongues being cooperable with said other of said guide receiving portions.

PAUL SCHELL.

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

UNITED STATES PATENTS Number Name Date 533,385 Tweedale Jan. 29, 1895 1,371,210 King Mar. 8, 1921 1,947,291 Ford Feb. 13, 1934 2,305,415 Gofl Dec. 15, 1942 2,400,344 Frese May 14, 1946 FOREIGN PATENTS Number Country Date 13,525 Great Britain June 25. 1909 54,302 Norway Aug. 20. 1934

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