US1850771A - Electric switch - Google Patents

Description

E. C. RANEY March 22, 1932.

ELECTRIC SWITCH Filed Feb. 25, 1929 2 Sheets-Sheet elite Luv March 22, 1932. c, RANEY 1,850,771

ELECTRIC SWITCH Filed Feb. 25. 1929 2 Sheets-Sheet 2 gmwm fi/JM Cv 5' 7 I Patented Mar. 22, 1932 I 1,850,771

UNITED STATES PATENT" OFFICE ESTEL C..BANEY, OF COLUMBUS, OHIO p ELECTRIC swI'rcH I Application filed February 25, 1929. Serial No. 342,535.

My invention has for its object to provide the parts when the conductors of the switch an eflicient electric switch which is so conhave been clamped one against the other structed that the movable contact of. the while in Fig. 4 is shown the position of the switch will be pressed against the fixed conparts when the pressure is released from the 6 tacts with an increased pressure upon the conductors, either upon the-completion of 55 completion of the closing movement of the the closing movement of the movable conmovable contact. and whereby the pressure tacts or just in advance of the opening movewill be reduced in advance of an opening ment of the movable contacts. Fig. Gillusmovement of the movable contact. Ola-mp- 'trates a rear view of the movable parts of 10 ing the movable and fixed contacts, one the switch.

against the other with a heavy pressure, pro- The manually operated switch shown in duces a negligible drop of potential at the the drawings is provided with a movable elevcontactssince it reduces contact resistance to ment, or switch arm, 1, that is pivotally supa very small amount and, for the same reaported between a pair of movable contacts 2,

son,.heating of the contacts is eliminated. by means ofa bolt 3. The movable contacts 85 Also reducing the pressure in advance of any 2 are pivotally supported on the switch plate movement of the movable contact relative to or board 4, whereby the switch arm 1 may be the fixed contact, reduces wear and-enables operated to swing the movablecontacts or easyoperation of the switch. conductors 2 towards, or away from, the

'3 The invention provides a contact movable board 4 to close and open the switch and may 70 relative to a pair of fixed contacts that forrncontinue its pivotal movement, relative to the the terminals of an electric circuit, and an movable contacts to clamp the movable conelement for not only operating the movable tacts against the fixed contacts of the switch. contact, but alsoa means for pressing the In the particular torm of construction contacts together; Upon reverse movement shown, the movable contacts 2 are supported 76 of the element, the contact pressure is first for pivotal movements on one of the fixed con released and, upon further movement of the tacts, such as the fixed contact 10, and so that elements, the contacts v are separated. The the movable contacts 2 may be swung into actuating element may operate a suitable contacting relation with the other fixed con- 3 or a so ow, to press the contacts against each cured to the board 4 and means is provide for other or to release them according to the connecting the fixed contacts and 11 with movement of the actuating element. an external circuit in a manner well known in The invention may be contained in the art. r

switches of difierentforms and, to illustrate Preferably a pair of clamps 14 and 15 are a practical application of the invention, I used for pressing or drawing the movable have selected a switch containingthe invenand fixed contacts against, each other. The tion as an example of such structures and clamps 14 and 15 are located on the outer "shall describe it hereinafter. The switch sefaces of the movable contacts 2. The bolt in the accompanying drawings 4 the movable contacts 2 and the clamps are Fig-l-is a frontview of the switch. a Fig. held in position, one relative to the other, by

' 2 is a side view of a part of the switch. Fig. the pin 16 which pivotally supports the mov- 3 is a view of a section taken on the plane of able contacts 2 on the fixed contact 10. Pref- I the, line 3-3 indicated in Fig. 2. 3 Fig. 4 is erably, the inner faces of the clamps 14 and 95 a view of a section taken on the plane of the 15' are provided with sockets 17 for receiving line -4-'4 indicated in Fig. 1. In Fig. 5 the the end of the pin 16 that extends through the switch is shown in its open position while fixed contact 10 and the movable contacts 2. Figs-2 and 4 show the switch in its closed The pin 16 coacts with the bolt 3 to prevent. position. Fig. 2 illustrates the position of any angular displacement of themovable con- 30 wedgin or clamping member, such as a cam" i 'tact 11. The fixed contacts 10 and 11 are seso i le'cte'd for purposes of illustration is shown 3 extends through the clamps 14 and 15 and tacts and the clamps relative to each other,

and maintains these parts in their parallel and coactive relation. The pin 16 has a length and the sockets 17 have a depth sufli: 5 cient to maintain the parts .in this relation and yet to permit the clamps 14 and to clamp the ends of the movable contacts against the fixed contact 10 as well as the fixed contact 11.

The movable contacts are clamped together by the rotatiorrof the bolt 3 which is connected to the switch arm 1. The bolt 3 has'a head 20 that engages the outer surface of the clamp 14 and a nut 21 that engages the 5 outer surface of the clamp 15, and, consequentl rotation of the bolt 3'by the operation 0 the switch arm 1, will draw the clamps 14 and 15 towards each other by reason of the wedging surfaces formed by the thread of go a bolt coacting with the similar surfaces of the thread of the nut and consequently, cause the contacts 2 to be tightly pressed against the contacts 10 and 11. The bolt 3, as shown in Fig. 4, is provided with fiattened surfaces 22, while the switch arm is provided with an oblong opening 23 that fits the bolt where it isflattened and, consequently, upon a movement of the switch arm, relative to the movable contacts 2, the 80 switch arm will cause the bolt 3 to rotate and draw the clamps 14 and 15 towards each other, the nut 21 being locked in position so as to prevent rotation of the nut with the bolt. The nut 21 may be secured in position by any suitable means. In the particular form shown, the nut 21 has a cylindrical sleeve 25 that extends into an opening formed in the central part of the clamp 15 which is slotted as at 26 to afi'ord some flexibility as between opposite sides of the clamp 15. A pair of screw bolts 27 extend through parts of the clamp 15, located on opposite sides of the slot 26, one side being tapped to receive the threaded portions of the belts 27 and, when parts of the clamp 15 and is thus securely held as against rotation when the bolt '3 is rotated by the operation of the switch arm 1. Thus, the nut 21 may be adj ustably secured to the bolt and the arm, to vary the clamping pressure produced by the arm 1 operating upon the bolt and nut. Thesclamping pressure may be increased to such an extent as to bend the clamps. Preferably, the clamps are elastic to produce a maximum pressure per unit of area at the inner edges of the fixed contacts by reason of the flexing. of the clamps.

In order that the switch arm may be used for moving the movable contacts 2 towards and away from the closed position, and also to produce the clamping or releasing operations in each swinging movement of the switch arm, means is provided for automatithe bolts 27 are screwed down, the sleeve 25, of the nut 21, is clamped tightly between the cally releasing the movable contacts from the arm when the movable contacts have been placed iii-the closed position and also for connecting the switch arm to the movable contacts when the movable contacts have 7 been released from their clampedrelation to the fixed contacts. Thus, the switch arm is caused to pivotally move about the pin 16 during a part of each swinging movement and about the axis of the bolt 3 in another part of the movement. In order to thus positively swing the movable contacts into and away from the closing position, and yet to enable it to operate the bolt 3 to clamp the contacts together, a latch is provided which connects the switch arm'to the movable contacts and releases the switch arm from its positive connection with the movable contacts. The latch for thus interlocking the switch arm 1 with the movable contacts is operated upon movement of the movable contacts to a predetermined point relative to the fixed contacts and also when the movable contacts are moved away from the predetermined point.

In the form of construction shown, a spring pressed dog 30 is connected to the movable contacts and is operated by a fixed part that may be connected to, or form a part of, the board 4 when the movable contacts are located in switch closing position. The dog-is. preferably, pivotally supported by the pin 31 on the ears, or lugs, 32, formed on the edges of the clamps 14 and 15 and is spring pressed by the spring 33 to engage the switch arm. The inner end of the switch arm 1 is provided with a notch 38 that is adapted to beengaged by the nose 39 of the dog 30 when the switch arm 1 has moved a short angular distance to rotate the bolt 3 sufficiently to release the pressure between the movable contacts 2 and the fixed contacts 10 and 11. This positively connects the switch arm to the conductors and, upon continued movement 'of the switch arm, the switch arm will swing thc movable contacts, together with the clamps, about the pivot pin 16. a

When the switch is open, the parts will be as shown in Fig. 5. In the closing operation, the parts are rotated about the pin 16 and when the lower end of the dog 30 engages the board 4, in the upward swinging movement of the parts, the nose of the dog will be lifted out' of the notch 38, and, upon continued movement of the switch arm 1, the bolt .3 will be rotated and the clamps 14 and 15 will be drawn towards each other to clamp the movable contacts against the fixed contacts.

Preferably, the clamps 14 and 15 are so formed that they will engage and clamp only the end portions of the movable contacts. Their inner faces are, preferably, raised. as at 45, at points opposite the portions of the inner surfaces of the movable contacts that lower end of the dog 30 engages the strip 47. 1

It is thus "apparent that I have provided a switch which may be readily opened and closed and at the same time one which has a contact pressure many times greater than is possible where no means is provided for increasing the pressure after the contacts are in closed position. As a matter of fact, the contact pressure may easily be made 2000 lbs. or more and yet require a relatively small pressure on the operating means to efiect opening or closing. This renders a switch,

embodying my invention, especially adaptable ,for use in adverse atmospheric conditions, or for out-door service.

I claim: 1. In an electric switch, a pair of fixed contact terminals, a movable contact member for connecting the fixed terminals and pivotally mounted on one of the said fixed terminals, a.

clamping member mounted. on said movable contact member, a handle lever for operating said movable contact, a bolt rigidly connected to the said handle lever and located between the ends of the movable contact, a nut connected to the said clamping member, the said bolt being engaged by the threads of the nut,

whereby relative movement between the operating handle and the movable contact p'roduces a pressure between the movable contact and both of the said fixed contacts.

2. In a switch, a pair of fixed contacts,- a

- movable contact supported for pivotal movements relative to the fixed contacts, a pair of clamping members, the end portions of the clamping members located on opposite Sides of the fixed contacts, a handle lever, a bolt connected to the ,handle lever and rotatably supported on the said clamping members and located at a point intermediate the fixed contacts when the switch is closed, a nut located on the bolt and adjustably secured to one of the clamping members to produce the desired contact pressure between the ends of the movable contact and the fixed contacts-whenthe handle lever is rotated relative to the movable contact. N

3. In a switch, a pair of fixed contacts, a movable contact supported for pivotal movements relative to the fixed contacts, a pair 0 clamping members, the end portions of the clamping members located on opposite sides of the fixed contacts, a handle lever, a bolt connected to the handle lever and rotatably supported on the said clamping members and located at a point intermediate the fixed contacts when the switch is closed, a nut located cated at a point to produce substantially equal pressures of the ends of the movable contact against the first contacts when the handle lever is rotated relative to the movable contact.

' on the bolt and adjustably secured to one of; the clamping members, the bolt and nut 10- 4. In aswitch, a pair of fixed contacts and a pair of movable contacts, a pin movable longitudinally in one of the fixed contacts,

for pivotally supporting the movable contacts relative to the fixed contacts, the movable contacts adapted to make contact with the lateral faces of the fixed contacts, a pair of clamping members having sockets for receiving the ends of the pins, the bolt connected to one clamping member and the'other end located in the other clamping member and engaging the nut, means for adj ustably securing the nut relative to the last named clamping member, a handle lever connected to the bolt for operating the bolt and drawing the clamping members towards each'other and clamping the ends of the mov-f able contacts against the fixed contacts.

5. In a switch, a pair of fixed contacts, a movable contact supported for pivotal movements relative to the fixed contacts, a handle lever pivotally connected to the movable contact at a point intermediate the fixed contacts when the switch is closed and for swinging the movable contact to the closed position, a clamping member having ends located at the sides of the fixed contacts when the movable contact is in closed position, means for connecting the handle lever to the movable contact to prevent rotation of the handle lever relative to the movable contact, means for releasing the handle lever to permit rotation of the handle lever relative to the movable contact, means operated by the handle lever when it is rotated relative to the movable contact for clamping the movable contact'against the fixed contacts.

6. In a switch, a pair of fixed contacts, a movable contact, a pin extending through the movable contacts and one of the fixed conmom, a pai'r of clamping members havlng holes for receiving the ends of the pins, a bolt extending through the clamping members and the movable contact and rotatable relative to the clamping members and the movable contact, a handle lever connected to f tact to prevent rotation'ofthe handle lever relative .to the movable contact, and means for releasing the handle lever for rotating,

as 4 a bolt and a nut, one end of the bolt relative to the nut for clamping the movable contact against the fixed contacts whenthey are placed in closed position.

7. In a switch, a pair of fixed contacts, a pair of movable contacts, a pin extending through the movable contacts and one of the fixed contacts, a pair of clamping members having holes for receiving the ends of the pins, a bolt rotatable relative to the clamping members and the movable contact, and having end parts located in the clamping members and the movable contacts, a handle lever connected to the bolt, a nut threaded onto the bolt, means for adjusta'bly connecting the nut to one of the clamping members, a fixed member, a dog pivotally connected to the clamping memberspa spring for operating the dog to engage the switch arm for preventing rotation of the bolt relative to the clamping members, the dog having a part engaging the fixed member for releasing'the switch arm to permit rotating of the bolt when the contacts are in switch closed position.

8. In a switch, a pair of fixed contacts formingthe terminals of'a circuit, a pair of movable contacts for connecting the fixed contacts at the opposite ends of the movable contacts, and means located intermediate the fixed contacts and the ends of themovable contacts for drawing, at the said intermediate point, the movable contacts towards the fixed contacts to force the ends of the movable contacts against the fixed contacts.

9. In a switch, a pair of fixed contacts forming the terminals of a circuit, a mo"- able contact for connecting the fixed contacts at opposite ends of the movable contact, a pair of clamping members, the end parts of the clamping members for clamping the ends of the movable contact and the fixed contacts I together. means located'intermediate the ends of the clamping members and substantially central with respect to the movable contact 7 for drawing, at the said intermediate point,

the clamping members towards each other to clamp the ends of the movable contact and the fixed dontacts between the clamping members and producing approximately equal pressures at the ends of the movable contact against the fixed contacts.

10. In a switch, a pair of fixed contacts forming the terminals of an electric circuit, a movable con-tact supported for pivotal movements'relative to the fixed contacts and for making contact with the fixed contacts at the opposite ends of the movable contact,

a handle lever, a rotatable clamping member connected to the handle lever and to the movable contact and extending transversely with respect to the movable contact at a point intermediate the fixed contacts and the ends of the movable contact, when the switch is closed, for clamping opposite ends of the movable contact against the fixed contacts when the handle lever is rotated relative to the movable contact.

11. In a switch, a pair of fixed contacts forming the terminals of an electric circuit a movable contact supported for pivotal movements relative to the fixed contacts for making contact with the fixed contacts at opposite ends of the movable contact, a pair of clamping members, a pair of interengaging members extending through the clam in members ,at a point intermediate the x contacts and the ends of the movable contact, the interengaging members havin interwedging surfaces for drawing the c amping members towards each other, a handle lever connected to one of the interengaging members for rotating the interengaging member to which the handle is connected relative to the clamping members for forcing the ends of the clamping members towards each other and clamping the ends of the movable contact against the fixed contacts.

12. In a switch, a pair of fixed contacts a movable contact, means for increasing t e contact pressure after the movable contact is in a closed position, said means operating to apply pressure intermediate the fixed contacts and in a direction transverse to the movable contact and to transmit and distribute the pressure approximately equal to both fixed contacts.

13. In a switch, a pair of fixed contacts forming the terminals of a circuit, a movable contact for connecting the fixed contacts, a clamping member for clamping the fixed contacts and the ends of the movable contact, a handle member connected to the clamping member and the movable contact, a means operated by the handle member for pressing against a part of the clamping member located intermediate the fixed contacts to press the ends of the movable contact against the fixed contacts.

14. In a switch, a pair of fixed contacts forming the terminals of a circuit, a movable contact for connecting the fixed contacts, a handle member and means located substanstantially midway between the fixed contacts, when the switch is closed, and operated by the handle member for producing a pressure exerted transverse the movable contact at the central part of the movable contact for pressing the opposite ends of the movable colrlltact and the fixed contacts against each ot er.

In witness whereof I have hereunto signed

Images