US 2005684 A
Description (OCR text may contain errors)
June 18, J SACHS ELECTRIC SWITCH Filed June 10, 1952 Zm/EHUF JU 550k 555275 u( tangy UNITED sfrATEs PATEN or excessive moisture.
practice in Patented June 18, 1935 OFFICE ELECTRIC swrrcn Joseph Stiens, west Hartford, conn. Application .inne i0, 1932, serial No. 616,406 5 Claims. (Ci. 20o-144i the design and manuches or other circuit makces 'tomake luse of a sheet g material which is closely ich may be formed when the ed. These sheets or plates may be for the purpose of carrying movable or stationary contacts they may serve merely as muilies.
In many sheets or plates are r mechanical strength, be capable of resist particularly when s much as such `shee proximity to electri character as not to considerable extent by ares. For the sake of co general character will .be dei arc resistant.
Heretofore difficulty has been experienced in` obtaining an insulating sheet the desiredmechanica larly the required str which the material stance, ll have ioun sheet form or othe satisfactory mate or other conducting parts, or
separators, barriers or instances these` insulating equired to have considerable and for all uses they should ing warping cr ubjected' to moisture. ts or plates are used in close c arcs they should be of such eteriously affected to any the heat incident to the nvenience material oi this deformation,
inasreferreol to as being or plate which has l characteristics, particu ength and freedom from the same time is sumcient-I ning action of the arcs to may be subjected. d that vulcanized nicer, inA rwise, constitutes a reasonably rial as concerns resistance to For inn arcing, but unless specially treated it is not highly resistant to` moisture absorption, and fact is subject to considerable warping and deiorrnation when used under conditions ci" considerable the other hand, a
-molded or laminated material having a phenolic condensation compound vid or other artificial resin is highly resistant to moisture alo-- e carbonization. the invention ctric circuit making and g incorporated plate of the e is so related to the switchis to pro-7 therein a type described,
be understood illustrative only andis not iments of the that the drawing is intended tdbe invention, but it will -to be construed as ds- ,diiferent from those shown in Figs.
ical characteristics, need ing as a facing for the said sheet 2 is a sheet 3 Y son that the sheets 2 and E material adapted to be used in an electric .switch embodying the invention.
Fig. 2 is a view similar to Fig.. l, but showing j an alternate embodiment of the invention.
Fig. 3 is a perspective view of an electric switch lt embodying the invention, the insulating sheet or plate as shown in this iigure being structurally l and 2.
Figs. 4 to 7 vare fragmentary longitudinal sectional views showing the procedure which is preferably followed in making the switch member shown in Fig. t..
Fig. `8 is a view similar to Fig. 7, but showing a composite insulating plate of the type shown in Fig. v
Fig. 9 is a fragmentary view illustrating diagrammatically a different form of circuit making and breaking device embodying the invention.
Fig. lll is a perspective view showing a still different electric switch embodying the invention.
Referring particularly to lSig. l oi the drawing, t represents a composite sheet or plate of insulating material. As, shown, this composite plate comprises a relatively thick sheet 2 having certain vdesirable mechanical characteristics, such characteristics for instance being ample mechanical strength, freedom from brittleness. and a high degree ci resistance to moisture obsorpticn. The material ci they sheet 2, while having the aforesaid or other desirable mechannotL have and ordinarily does not have to asatisfactory extent the characteristic ci being highly resistant to the burning eiect incident to an electric arc. Servof an insulating material different trom the materiai constituting the sheet 2 and having arc resisting characteristics superior to those of the sheet 2. lThe said` sheet S is ordinarily thinner than the sheet 2 and it need not have and ordinarily does not have the same desirable mechanical characteristics which are incident to sheet E. Any mechanical weakness or lack of stability'in the sheet 3 is. immaterial for the reaare connected together so that the-sheet 3 provides the necessary strength and stability. While'the invention is not necessarily so limited, Fig. l shows a composite plate having two facing sheets 3 arranged at opposite sides ot the 55 i ilar to the sheet I Y only one facing sheet 2 insteadl of two such facing sheet 2. Fig. 2 shows a composite plated simshown in Fig. 1, but having sheets.
There are severalmaterials from which the main sheet 2 maybe formed. For instance, it may be formed of a molded or laminated material having as a binder a suitable phenolicl condensation compound or other artificial resin, or it maybe molded from some other plastic material `having the required characteristics. AFor the facing sheetor sheets 3 use is made of a material of the cellulose class, vulcanized ber being particularly suitable for this purpose. .Vulcanized fiber has the highly important advantage that in the presenceof excessive arcing it gives out gases in relatively `large quantities 'which assist in dissipating the arc.
The sheets 2 and 3 may be connected by vmeans of a suitable cement, preferably a waterproof cement. When the sheet 2 comprises or includes an artificial resin advantage may be taken of the adhesive properties of the resin to cause the required adhesion between the two sheets. The sheets may be placed together while the artificial resin is still in an uncured or plastic condition and the two sheets may be pressed together in a mold or otherwise during the process of curing and hardening the resin. The resin will thus be ,forced into intimate contact with the material of the sheet or sheets43 and the sheets 2 and 3 will thus be held together throughout their entire areas by thel adhesive action of the resin.v While l. ordinarily prefer to connect the sheets by a cementing or adhesive action, such as described, they may be connected by a suitable mechanical connecting means such as rivets. In Fig. 3 I have shown 'a composite plate 5 having the components 2a and 3a, 3B thereof connected together by means of rivets E, 6. v
-As shown in Fig. 3`the composite plate 5 is so shaped as to constitute the insulating element of a sliding switching member. The switch of which the plate 5 forms a partis shown only incompletely. Inaddition to the plate Ei,A the switch includes a base 1 on which is mounted at least one andv preferably twofstationary switch contacts 8, 8. When there shown they are preferably mounted oppos'te each other and are provided vwith, opposite parallel contact faces. As shown the two contacts are directly connected respectively with wire termi:-
nals 9, 9. The movable switching member con-v sists in part of the plate 5 which is guided for nmovement ina fixed path between the two stationary' switch contacts B,`8. The plate 5 is shown as having Vtwo parallel guiding edges by means of which it is constrained to move in "a rectilinear path. TheC switch member also includes a movable contact I0 carried by the insulating plate 5. When there are two stationary contacts such as 8, 8 the contact I0 is provided with two opposite lateral portions having confy K tact faces I0,
I0 adapted respectively to engage or dsengage the two stationary switch contacts to thereby close oropen the circuit.
As shown the base 1 is provided with a slot in which the lower or rear edge of the insulating plate 51s entered, the bottom of the slot engaging one of the said guiding edges of the plate.
' A suitable means, not shown, is preferably provided for engaging the front edge of the insulating plate 5, which means cooperates with the base 1 to guide the plate in a rectilinear path as already mentioned. There may be provided a `formed in the shape shown may be .easily put in -has been put in place yment of the contact l0, but .the facing sheets are two switch contacts asgagement .with the stationary contact I3.
Imediately adjacent cranked operating member, not shown, for efEect--\ ing movements of 'the switching member. The insulating plate 5 is provided with a slot 5a through which the operating member canv extend and it will be apparent thaty when the crank is moved it effects corresponding movements of the` switching member. i
The sheet 2a is preferably formed with an opening II and the contact I0 isl preferably initially in Fig. 4 so that it After being entered in the openis moved to the lower position in- 5 and a block I2 is indicated in Fig. 6. When il as indicated. ing as shown it dicated in Fig. in the opening II as bent to its final form as shown in Fig. 1. It will be understood that when the facing sheets 3B, 3*v are connected by a mechanical means to the central sheet 28 the c ontact is'or may be put in place in the manner described prior vto the attachment 6i the facing sheets 3a, 3a. Each facing sheet is shaped to conform to the desired outline of the complete composite plate and in addition it is provided with an'opening therein adapted to receive the corresponding projecting lateral por-VV tion of the contact I0. This will be apparent from an inspection of Figs. 3 and 1. After the contact as described, the facing sheets 3a, 3e are assembled to the central sheet 2B and then all three sheets are connected toplace through the opening then inserted gether by means of the before-mentioned rivets With this construction the same procedureis or may be followed in connection with the attach- 3, 3 are not provided with an opening to receive the projecting' portions of the Vcontact I0.
f. The advantages' of my improved compositel insulating plate and of a switch incorporating such a plate will be apparent from a consideration of Fig. 3. Inasmuch as the relatively thick central sheet 2a is mechanically strong and is resistant to deformation such as that resulting from moisture absorption, the said composite plate 5 is well adapted to perform its required'mechanical functions of holding and actuating the contact I0.
The facing sheets 3, 3a are resistant to the burning effect of any arcs, ite plate 5 is adapted to'resist such deterioration as might occur if the said facing sheets were not provided. The said facing sheets 3, 3 are im mdiately adjacent the arcs and serve to completely protect the centralsheet 2. l Fig. 9 represents somewhat diagrammatically a switch or circuit making,and breakingdevice `having a stationary contact I3 and a movable contact I4 is carried contact I4. lThe movable by a composite plate I5 which lis pivotally` movable about an axis atfIIi. When the plate I5 vis and therefore the composactuated by a suitable means, not shown, the movable contact Il can be brought into or out of en- The ptite I5 is a composite one which may conform in structure to the sheet 4 shown in Fig. 2. iIt will be apparent that the facing sheet 3b is imany arcs that may be'formedwhenthe two contacts I4 and yI3 are separated.
land thus protects the sheet 2P from any tendency J5 andasse to burn or otherwise deteriorate as the result oi the arcing action.
In Fig. l I have shown a. switch of the knife blade type having a pivot contact il and a rupture contact it. n blade I9 is pivoted tothe contact il and is adapted to enter or leave the contact it to establish or break the electrical-connection through the switch. In order to conilneand control any arcs that may be formedwhen the blade i9 is withdrawn, there are provided two barrier or muflie plates 2G, 2U which are positioned immediately adjacent the outer portions of the contact it, being held inv place by a U-shaped metallic clip 2i. The two plates 20, 20 are or may be oi the same construction as the plate 4 already described. It will be apparent that the arc resistant racing sheets 3, 3c serve to prevent any burning as the result ci contact with arcs which may be formed.
What I claim is:
l. In an electric switch, the 'combination of a stationary switch contact, a composite insulating plate movable in a fixed path adjacent the stationary contact, and a movable switch contact carried by the said plate at one side thereof and adapted to cooperate with the stationary contact, the said composite plate comprising a sheet oi insulating material resistant to breakage or deformation and a sheet oi different insulating material serving as a facing for the first said sheet at the surface thereof adjacent the said contacts and having arc resisting characteristics superior to those of :the first said material.
2. In an electric switch, the combination of a stationary switch contact, a composite insulating i plate movable in a iixed path adjacent the stationary contact," and a movable switch contact carried by the said plate at one side thereof and adaptedto cooperate withv the stationary contact, the said composite plate comprising a sheet of insulating material including articial resin and resistant to breakage or deformation and also comprising a sheet of vulcanized fiber serving as 'a facing for the articial resin material and having arc resisting characteristics superior thereto.v
K 3. In an electric switch,v the combination of a pair or opposed stationary switch contacts, a composite insulating plate movable in a fixed path extending between the said stationary contacts, and a movable switch contact carried by the said plate and projecting therefrom at both sides thereof and adapted to cooperate with both of the said stationary contacts, the said composite plate comprising a sheet of insulating material resistant to breakage or deformation and two sheets of different insulating material serving as facings for the first said sheet at the lopposite surfaces thereof adjacent the respective stationary and movable contactsand having arc resisting characteristics superior to those of the first said material.
t. In an electric switch, the combinationjof a pair of opposed stationary switch contacts, a composite insulating plate movable in a fixed path extending between the said stationary contacts, and a movable switch contact carried by the said plate and projecting therefrom at both sides thereof and adapted to cooperate with both of the said stationary contacts, the said composite plate comprising a sheet of insulating material including artificial resin and resistant to breakage or deformation and also comprising two sheets of vulcanized fiber serving as facings at opposite sides oi the first said sheet and having arc resisting characteristics superior thereto.
5. In an electric switch, the combination of a pair of opposed stationary switch contacts, an insulating sheet movable in a fixed path extending between the said stationary contacts, a movable switch contact carried by the said sheet and hav ing projecting lateral portions extending along and in close proximity to the opposite faces thereof, the said lateral portions being adapted 'to cooperate with the respective stationary contacts, and two sheets of different insulating material serving as iacings lor the iirst said insulating sheet at the opposite surfaces thereof adjacent the respective stationary and movable contacts and'having arc resisting characteristics superior to those oi7 the rst said sheet, the said facing sheets having openings therein for receiving the Y portions of the movable contact which extend along the opposite faces of the first said sheet.l