US1887420A - Electric switch - Google Patents

Description

N EA M AN Nov, 8, 1932" EEEGTRIC SWITCH Filed April 5, 1930 5 Sheets-Sheet l gwwmtoz TJA/ewma/z attmqo Nov. 8, 1932. T. J. NEWMAN 1,887,420

I ELECTRIC SWITCH Filed April 5. 1930 s Sheets-Sheet 2' TJjVe w/nan 1 v dumm Nov. 8, 1932. T, J. NEWMAN 1,887,420

ELECTRIC SWITCH Filed April *5. 1930 5 Sheets-Sheet I5 gwownloz TJNe lama/2 switch Patented Nov. 8, 1932 thit'thh THOIITAS J.

NEWMAN, OF CANTON, OHIO ELECTRIC SWITCH Application filed April 3, 1930.

The invention relates to electric switches and more particularly to a test switch adapted for testing meters or other devices having both current and potential.

The object of the in'iprovement is to provide a switch of this character which may have at least one potential pole and any desired number of current poles double throw blades being provided, each blade having a gear segment thereon, a pinion engaging the gear segments of all of the blades for simultai'iecusly moving the same.

A further object of the improvement is the provision of a double throw switch blade for each current pole for alternate engagement with two sets of contact jaws adapted to engage one set of jaws before it is entirely withdrawn from the other set of jaws.

Another object is the provision of such a in which the contact is made by the current carrying blade before tie potential blade contacts with its corresponding contact jaws and in wh' the contact is broken by the potential blade before the current carrying blade is entirely withdrawn from its corcontact aws.

Another object is to provide switcii including a pi ion and oppo itely disposed douo e throw switch blades provided with gear opposed I .nts upon the pinion and arranged to be simultaneously moved in reverse directions thereby.

A still further is to provide the switch o provided to n ct of the improvement 1 i y for throwing on, means being over of the hey only when the sv r objects may be at trusting improved switch 1 ared in the accompanyin which i re 1 a plan 'ew of the switch showing the same assembled upon a switchboard the top cover plate of the switch casing being remover. for the purpose of illustration;

Fig. 2, a front elevation of the switch;

Serial No. 441,366.

Fig. 3, a transverse sectional view through the switch showing one pair of current carrying blades in running position;

F 4., a similar View showing the blades moved to a position where one end of each blade is inserted into the adjacent contact jaws while the opposite end thereof is not entirely withdrawn from the corresponding contact jaws;

Fig. 5, a section similar to Fig. 3, showing one pair of the potential blades in running position;

Fig. 6, a similar section showing each potential blade entirely withdrawn from both contact jaws;

Fig. '7, a wiring diagram showing the connection of the improved switch to a meter and the like; and

Fig. 8, a detail perspective View of the operating key for the switch.

Similar numerals refer to similar parts throughout the drawings.

The improved switch is preferably enclosed within a casing 10 of any suitable insulation material preferably provided with removable covers 11 and 12 for the top and bottom thereof respectively and arranged to be connected thereto as by the screws 13.

The switch is adapted to be operated by means of a pinion 1a preferably of bakelite or other suitable insulation material fixed upon the rotatable shaft 15 and preferably extending throughout substantially the length of the casing in which the switch is mounted so as to operatively engage all of the switch blades, as will be later described.

The improved switch is arranged to be mounted upon a switchboard or the like, as shown at 16, the insulation casing 10 being mounted upon the inner or rear side thereof as by the screws 17, the switchboard being provided with an opening 18 through which the outer end of the operating shaft 15 is extended.

A face plate 19 is fixed upon the outer side of the switchboard as by the screws 17 and provided with a central opening 20 axially alined with the shaft 15 and having the diametrically opposed notches 21 arranged to when the switch is in the normal operating position.

For the purpose of operating the switch a key is provided having the tubular shank 23 adapted to be inserted through the central opening 20 of the face plate and having di ametrically opposed studs 24 arranged to pass through the notches 21 in the face plate, the inner end of the key shank being grooved on opposite sides as at 25 to receive the studs 22 upon the shaft 15, these grooves being of suflicient length to accommodate switchboards of varying thickness.

It will be seen that the key can be inserted or removed only with the parts in the open ating position, thus making it impossible for the operator to test the meter, or other device to which the switch is connected, and then remove his key while the switch remains in the testing position.

Switches of this type may have one or more sets or pairs of potential blades and any desired number of sets or pairs of current carrying blades and for the purpose of illustra-- tion, the switch shown in Fig. 1 is provided with one pair of potential blades and three pairs of current blades while in the diagram illustrated in Fig. 7 two sets of potential blades and a like number of current blades are shown.

Each of the potential blades 26 is pivoted intermediate its ends as at 27, upon a pivot contact 28 connected to a binding screw 29 extending through the adjacent wall of the casing for the connection of a wire and the like.

Each blade is substantially of obtuse angular form and provided on its inner edge with a gear segment 30 meshing with the pinion 14 whereby the blades of each pair or set may be moved in unison by rotation of said pinion.

The ends of the blades 26 are arranged to alternately engage the contact jaws 31 and 32. Each jaw is substantially U-shaped and has both of its arms bent backward parallel to each other, forming the resilient blade engaging portions 33.

A screw 34 is provided'for fastening each jaw upon the adjacent sidewall of the cas ing, the head 35 of the screw being received within the U-shaped jaw and a nut 36 being provided for firmly attaching the same in place, the screw serving as a binding post for attaching a wire or the like.

As shown in Fig. 5, when the upper end of one blade 26 is engaged with thecorresponding jaw 31, the lower end of the other potential blade is engaged with the corresponding jaw 32.

When the pinion 14 is operated to move the blades out of engagement with these jaws it will be seen. as shown. in Fig. 6, that each blade is entirely released from one jaw before the other end of the blade contacts with the other jaw, whereby the potential blades be moved to an entirely neutral position, as shown in said figure.

Each of the current blades 37 may be of substantially the same form as the potential blades above described, having a gear segm nt 38 formed upon its inner edge for engagement with the pinion 14.

These lades are each pivoted, intermediate their ends, upon the pivot contacts 39, as indicated at 40, each pivot contact being fixed upon the adjacent side wall of the insulation casing as by a screw 41 which serves as a binding post for attaching wires and the like The upper end of each current blade 37 is arranged to engage a contact jaw 42 of substantially the same construction as the jaws 31 and 32, and attached to the adjacent side walls of the insulation casing as by a screw 43, forming a binding post for attaching wires and the like. The lower end of each current blade is adapted to engage a similar contact jaw 44 attached to the casing as by the scr w 45.

As shown in Fig. 3, the current blades are so arranged that when the upper end of one blade engages the corresponding contact jaw 42, the lower end of the other blade will engage the corresponding contact jaw 44 but, as shown in F 4, the current blades are so arranged that each blade will make contact with one jaw before breaking contact with. the other jaw, thus preventing formation of an are when the switch is thrown from oper ating to test position or vice versa.

It will also be seen, as best shown in Fig. 1, that the potential blades are so arranged with relation to the current blades that they will break contact with the jaws before the current blades break contact while they do not make contact with the jaws until after the current blades have made contact with their respective jaws.

Thus, when the current blades assume the position shown in Fig. 4 with both ends of each blade contacting with its respective jaws, the potential blades will be in position where neither end thereof is in contact with the jaws.

As above explained, the switch may be made up in any combination of potential and current blades although in Fig. 1 the switch is shown with one set of potential blades and three sets of current blades, for the purpose of illustrating the flexibility of the invention, Fig. 7 shows the improved switch diagrammatically with two sets of potential blades 26 and two sets of current blades 37.

Wires 50 may lead from any suitable source of electric supply, a transformer 51 being interposed between said wires and the wires 52 and 53 leading to opposite sides of an in dicating watt meter 54, and the wire 55 leading to the pivot contacts 28 and 39 of an adj acent potential and current blade 26 and 37 respectively.

Wires 56 and 57 lead from the indicating watt meter to the pivot contacts 28 and 39 of the other potential blade and current blade on the same side of the switch.

The indicating watt meter is also connected to the wires 58, 59 and 60 which lead to a potential bus and which are connected to the potential studs 61, 62 and 63 respectively.

The wire 58 is connected, as by the wire 64, with the contact jaw 31 of one of the potential blades on the opposite side of the switch;

7 the wire 59 is connected as by a wire to side of the switch is connected, as by the wire 69, with the meter 68.

A bus bar or the like indicated at connects the jaws 31 and 32 of this potential blade to the jaw 44; of the adjacent current blade, while the aws id and 32 of the 0th r current blade and potential blade upon this side of the switch are connected together as by a wire 71. The pivot contacts 39 of the two current blades upon this side of the switch are connected as by the wires 72 and 73 with opposite sides of the meter 68.

On the other side of the switch the contact jaws 31 and 1-2 of both potential and current blades are all connected together as by a wire or bus bar 7 1-. The contact jaw 44 cf the lowermost current blade on this side is connected, as by the wire with a wire 76, one end of which is connected to the stud 77, the other end leading to the meter 68.

The contact jaw leiof the next adjacent current blade is connected by a wire 77 with a wire 7 8, one end cf which leads to a stud 79 the other end leading to the meter 68.

A wire leads from the meter 68 to the contact jaw 32 of the next adjacent potential blade and then to a stud 81 while a wire 82 leads from the contact jaw 32 of the other potential blade on this side of the switch and then to a stud 83.

The wire 70 on the opposite side of the switch leads to a stud 84: and an adjacent stud is connected by a wire 86 wit the contact jaw d4 of the lower .iostblade on. the left .ide of the switch and then leads to the contact jaw 42 of the same blade.

It should be understood that this diagram illustrated in Fig. 7 is merely for the purpose of illustrating one manner in which one type of the improved switch may be connected to a meter for testing the same and that various other circuits may be used in connecting other types of the improved switch to meters or other devices to be tested.

The measuring device 54; is an indicating wattmeter placed in the circuitand has no connection with the switch, but is meant to show that any number of instruments can be connected in the circuit which can be recording, integrating or relays and the switch operation would affect only the particular in strument to which it was connected. In the case of Fig. 7, lines 50 show a three-phase incoming line feeding through an oil switch. To reduce this primary circuit for metering purposes, transformers indicated by numeral 51 are connected in circuit for secondary metering purposes. ires 52 and 53 carry the current through indicating wattmeter 54 and then are followed through 56 and 57 to test switch together with wire 55. They are connected through the necessary switch members up to the integrating watthour meter 58 returning by lines 78 and 80 to switch to complete the circuit. A voltage bus shown by 58, 59 and 60 supplies energy for the potential coils of the meter through wires 64, 65 and 66 to test switch members, then through 67 and 73 to potential coils of meter, out on wires 72 and 69 through test switch to Wire 65 to complete the potential circuit. In the case of wiring in Fig. 7 the integrating watthour meter 68 only is connected to the test switch and the operation from the running or operating and test position does not affect in any way indicating wattmeter 54. Likewise any other instruments or relays can be introduced in the circuit and not be affected by the operation of the switch or the instruments to which it is connected.

Fig. 7 shows terminal binding posts 85, 84:, 83, 81, 77 and 79 mounted close by or adjacent to the test switch. In normal running position of the switch, these terminal studs or binding posts are not in use. When it is desired to test the instruments, it is accomplished by attaching to these studs a definite but variable current through the operating coils and by means of rotating standard the accuracy of such an instrument can be ascertained. With the switch in the testing position the two potential coils in the meter have been paralleled and brought out toterminals 85 and 84. To energize this source terminal studs 61, 62 and 63 have been placed on the board to supply the voltage energy required. Terminals 83, 81, 77 and 79 represent the four ends of two current coils and these are, when the switch is in the test position, absolutely free and clear of any circuit, whatever, and any method of testing. either series, paralleling or buckling can be made with case.

After the test has been completed and all adjustments been made, the testing instruments are removed from the binding posts or tion and the meter is returned to the circuit for its operating purpose. During this entire test the indicating wattmeter 54: was not in any manner disturbed and a reading could have been taken at any time during the test.

I claim:

1. A switch for the control of metertesting circuits having potential wires and current wires, comprising the following instrumentalitics: current terminals and potential terminals adapted for connection to an instrument to be tested, fixed and movable elements arranged in sets with acommon operating device geared to the movable elements in all the respective sets, said fixed and movable elements being relatively so constructed and arranged that the circuits of the potential terminals will be automatically opened before the circuits of the current terminals are opened, and the circuits of the current terminals will be automatically closed before the circuits of the potential terminals are closed in the rotation of the operating de vice forward and backward, respectively.

2. The switch described in claim 1, in which all the switching elements are mounted on a switchboard with the operating device accessible from the frontof said switchboard and a key and connections adapted to move said device into either one of two positions for operating or testing at will, said testing position being adapted to carry the movable elements far enough in one direction to fully close the current contacts and then the potential contacts, and the operating position being adapted to carry the movable con tacts through reverse travel with the potential contacts being first broken and then the current contacts broken in turn.

3. The switch described in claim 1, in which the movable elements are pairs of pivotally mounted switch blades, the operating means being interposed between and geared to the corresponding pairs of blades for simultaneously operating both blades in each pair in the same direction, separate pairs of blades being connected to the current terminals and to the potential terminals respectively, said blades being adjusted to open and close the circuit connections to said current terminals and to said potential terminals in direct and reverse sequence according to the direction of rotation of the operating memher.

4. The switch described in claim 1, in which the movable elements are pivotally mounted switch blades, a gear segment upon each blade, an operating pinion common to all the blades interposed between and meshing with the gear segments of the blades, a contact for engagement with each end of each blade, said gears and the blades being adjusted to move one end of a blade into engagement with a corresponding contact before the other end of said blade is withdrawn from the other contact.

5. The switch described in claim 1, in which the movable elements include a po tential blade and a current blade, each pivoted intermediate of its ends, contacts for engaging each end of each blade, a rotatable pinion in common engagement with the blades for simultaneously operating said blades, said pinion acting to withdraw one end of the potential blade from engagement with the corresponding contact before the other end engages its other contact, and for engaging one end of the current blade with its corresponding contact before the other end is withdrawn from its other contact.

7 G. The switch described in claim 1, in which the movable elements include a potential blade and a current blade, each pivoted intermediate of its ends, contacts for engaging each end of each blade, a rotatable pinion in common engagement with the blades for simultaneously operating said blades, said pinion acting to withdraw one end of the potential blade from engagement with the corresponding contact before the other end ei'igages its other contact, and for engaging one end of the current blade with its corresponding contact before the other end is withdrawn from its other contact, said rotatable pinion further acting to withdraw both ends of the potential blade from the corresponding contacts while both ends of the current blade remain engaged with the corresponding contacts.

7. The switch described in claim 1, in which all the movable parts and the cooperating fixed parts are mounted within a rectangular closed casing, a plurality of sets of fixed contacts secured along each side of said casing, each set comprising two terminal contacts and an intermediate terminal with a switch blade pivoted thereon, gear teeth formed on the inside of each switch blade, a rotatable operating member extending the length of said casing with one end constituting an operating terminal protruding from the outside of the casing, gear teeth on said operating member engaging the gear teeth on the switch blades, said fixed terminals, switch blades, and operating member, being so adjusted that by turning the operating member in one direction or the other, for operating or for testing, the several switch blades may so turn on their pivots as to close their several contacts and circuits connected thereto, asynchronously.

In testimony that I claim the above, I have hereunto subscribed my name.

THOMAS V J. NE'WMAN.

Images