US3372353A

US3372353A - Toggle operated electric vacuum switch

Info

Publication number: US3372353A
Application number: US588104A
Authority: US
Inventors: Merlin R Jensen
Original assignee: Electric Machinery Manufacturing Co
Current assignee: ELECTRIC MACHINERY INDUSTRIAL CONTROLS Corp A DE CORP
Priority date: 1966-10-20
Filing date: 1966-10-20
Publication date: 1968-03-05
Anticipated expiration: 1985-03-05

Description

March 5, 1968 Filed Oct. 20, 1966 M. R. JENSEN TOGGLE OPERATED ELECTRIC VACUUM SWITCH G) Ll 2 Sheets-Sheet 1 ID v INVENTOR. MERLIN R. JENSEN WEW ATTORNEY March 5, 1968 M. R. JENSEN TOGGLE OPERATED ELECTRIC VACUUM SWITCB 2 Sheets-Sheet 2 Filed Oct. 20, 1966 INVENTOR. MERLIN R. JENSEN WQM ATTORNEY United States Patent Ofllice 3,372,353 TOGGLE OPERATED ELECTRIC VACUUM SWITCH Merlin R. Jensen, Minneapolis, Minn, assignor to Electric Machinery Mfg. Company, Minneapolis, Minn, a corporation of Minnesota Filed Get. 20, 1966, Ser. No. 588,104 4 Claims. (Cl. 335-26) ABSTRACT OF THE DESCLOSURE A vacuum electric switch operated by an electromagnet by means of toggle mechanism and including resilient means concentric with one of the contacts for holding the contact in either closed or open position.

The herein disclosed invention relates to electric switch mechanisms and particularly to a mechanism adapted to handle heavy currents such as utilized in large electric motors.

An object of the invention resides in providing a mechanism utilizing a vacuum switch together with an electrically operated opening and closing device.

Another object of the invention resides in utilizing a toggle linkage for the purpose, whereby suflicient pressure can be procured between the contactors to pass the desired amount of current with minimum arcing.

A still further object of the invention resides in providing resilient means in the form of a spring for urging the contactors apart to normally leave the switch open.

An object of the invention resides in providing additional resilient means in the 'form of a spring between the movable contactor and the toggle linkage to maintain pressure between the contactors at all times when the switch is closed.

Another object of the invention resides in providing interconnecting means between the toggle linkage and the movable contactor and against which both springs react.

A feature of the invention resides in constucting the interconnecting means with a cylindrical wall having an end wall extending across the same at one end and a flange extending outwardly therefrom at its other end.

Other objects of the invention reside in the novel combination and arrangement of parts and in the details of construction hereinafter illustrated and/or described.

In the drawings:

FIGURE 1 is a side elevational View of the invention.

FIGURE 2 is a fragmentary plan sectional view taken on line 2-2 of FIGURE 1.

FIGURE 3 is a fragmentary plan sectional view taken on line 33 of FIGURE 1.

The invention consists of a vacuum-type switch elongated in form together with a supporting structure 30 also elongated in form and connected to and lying in continuation of said vacuum-type switch. This structure is mounted on a truck 40 and is insulated therefrom. A toggle linkage 50 is carried by the support 30 and is actuated by an electromagnet 70 which is mounted on said truck.

The truck 40 consists of a base 41 having flanges 42 at the sides of the same and which extend upwardly from said base to form uprights 43, which are located at the ends of the truck. The flange-s 42 are connected together at their upper ends by means of shelves 44. Between the flanges 42 at the lower end of the same are shafts 45 on which are rotatably mounted truck wheels 46. Mounted on the shelves 44 are

insulators

47 and 48 which support the vacuum switch 10 and the support 30 as will be presently described.

3,372,353 Patented Mar. 5, 1968 The switch 10 consists of a tube 11 constructed in two sections 11a and 11b of ceramic material.

End plates

12 and 13 are provided at the ends of said tube and have shouldered portions 14 received in the ends of said tube for centering said end plates relative to the tube. These parts are secured together by a special process akin to welding. Secured to the end plate 13 is a contactor 15 having a shank 16 extending through said end plate and terminating within tube 11 in a contact 17. The shank 16 extends outwardly beyond the plate 13 where it has attached to it a connector not shown. Opposite the contactor 15 is another contactor 18 which has a shank 21 in alignment with shank 16 and slidably mounted in a guideway 22 formed in the end plate 12. To prevent leakage past the guideway 22, a metal bellows 23 is employed which is attached to the end plate 12 and to the shank 21. The shank 21 also has a contact 24 on the inner end of the same facing the contact 17. A shield 25 secured to shank 21 encircles the bellows 23 while another shield 26 has a flange 25a disposed between the adjoining sections 11a and 11b of the tube 11 and encircles shield 25 and the

contacts

17 and 24 and prevents molten metal from being deposited on the tube 11.

The support 30 is formed with two

side members

31 and 32 connected together at one end by means of an end member 33. The other end of said support has extending across it a flange 34, across the top of it a top 35 and at the bottom thereof a bottom 36. Adjacent the flange 34 the top 35 is formed with an opening 37. A bracket 38 is bolted to the end member 33 and rests on and is attached to the insulator 48 by means of a bolt 39. The flange 34 on support 30 is bolted to the end plate 12 of switch 10 by means of threaded studs 28 issuing from said end plate and nuts 29 screwed thereon. The end plate 13 of switch 30 has bolted to it a bracket 19 similar to the bracket 38 and which is attached to the insulator 47.

Within the confines of the support 30 is mounted the toggle linkage 50. This linkage consists of two

arms

51 and 52 which are pivoted together at their adjoining ends by means of a pin 53. The arm 51 has a central boss 54 journaled on said pin and the arm 52 has two

bearings

55 and 56 straddling the boss 54 and also mounted on the pin 53. The arm 52 further has an elongated boss 57 at its other end which is rotatably mounted on a pin 58. This pin extends through the

side members

31 and 32 of the support 30 and supports the arm 52 for up and down swinging movement.

Pivoted to the pin 53 is a link 60 which has spaced

bearings

62 and 63 which stradle the boss 54. This link travels in a substantially vertical direction and serves to move the two

arms

51 and 52 in a direction tending to bring these arms into or out of alignment.

The arm 51 is formed at its end with a fork 64, which straddles a tubular slider 65. A pin 66 secured to the ends of fork 64 extend through openings 67 in said slider and supports arm 51 for swinging movement relative to said slider. The slider 65 is slidably mounted on a bolt 71 screwed into the shank 21 of contactor 13 of switch 10. Coaxially disposed relative to the shank 21 is an in terconnecting means 80. This means has a sleeve 81 encircling the slider 65 and bolt 71 and formed with a bore 82 of greater diameter than said slider 65 and bolt 71 to form an annular space 82 therebetween. A socket 83 in the slider 65 communicates with the space 89. At one end of sleeve 81 is an end wall 84 which receives the bolt 71 and which is rigidly clamped against the end of shank 21 thereby. At its other end sleeve 81 has formed on it an outwardly extending flange 88. The flange 88 rides in a bore 85 formed in the support 30 and the sleeve 81 thereof is spaced from said bore to provide a space 86 between said bore and sleeve. The bore 85 terminates short of the flange 34 of support 30 to form a shoulder 87 at the end of said bore. Mounted in the space 89 and socket 83 is a compression coil spring 91, which is seated at one end against the end of the slider 65 and at its other end against the inner surface of the end wall 84 of the interconnecting means 80. Also in the space 86 is a spring 92, which is seated at one end against the shoulder 87 and at the other end against the flange 88.

The chamber within the tube 11 being under vacuum, atmospheric pressure on the end of the shank 21 would force the contact 24 into engagement with the contact 17 and close the switch. However, spring 92, acting on the interconnecting means 80, moves said means outwardly and opens the switch, thus maintaining the switch normally open. When pressure is applied to the slider 65, the same moves along the space 89 and pushes on spring 91. Spring 91 is more rigid than spring 92, and the int-erconnecting means 80 is moved inwardly until the switch closes. After the switch has closed the slider 65 continues its travel compressing spring 91 and applying a certain pressure on the

contacts

17 and 24 which is sufficient to prevent arcing and deformation of said contacts while the switch is closed. Upon release of pressure on the slider 65, spring 91 forces the slider back against the head of the bolt 71 imparting a shock to the shank 21 and thus breaking any minute welding between the contacts and finally forcing the contacts apart. At this position further movement of the slider aided by the spring 92 fully opens the switch.

For operating the toggle linkage an electromagnet 70 is employed. This electromagne-t consists of a core 101. The magnet core includes a vertical leg 103 and a horizontal leg 104 issuing outwardly therefrom. Extending upwardly from the leg 104 is a central leg 105, which is cylindrical in form. Encircling the leg 105 is a coil 106 which may be of suitable construction. The electromagnet 70 is mounted on the base 41 of truck 40, and is secured thereto by means of screws 107, which extend through said base and are screwed into the leg 104 of the core 101.

Extending outwardly from the vertical legs 103 of core 101 are two bearings 108, which rotatably support a shaft 111. This shaft has secured to it by means of a bolt 112 an armature 113, said armature being adapted to occupy the position shown in full lines in FIGURE 1, or to a position in which the same overlies the pole faces 114 and 115 of the core 101. The armature 113 has attached to it by the same bolt 112 a lever 116. This lever has a boss 117 at its outer end. An insulated link 61 is bolted to the link 60 by means of bolts 79. This link has a fork 118 at its outer end which straddles the boss 117. A pin 119 passes through this fork and through the boss 117 and journals the lever 116 for swinging movement relative to the link 61. Upon energization of the coil 106 of electromagnet 70 armature 113 is drawn downwardly, raising the links 61 and 60. This moves the two

arms

51 and 52 toward alignment, urging the slider 65 for movement in a direction tending to close the switch 10.

Stops

121 and 122 secured to support 30 and base 41 limit movement of the toggle linkage 50.

The method of using the invention is obvious. The mechanism being mounted on a truck can be wheeled into position within the control structure with which it is to be used. The current to be conducted is led to the shanks 16 and 2.1 of the switch by means of suitable leads or cables not shown. Any suitable connector may be used for connecting such leads or cables to the protruding ends of the said shanks. In the case ofthe shank 21, the leads and connector are movable in the opening 37 in the support 30. The electromagnet 70 is connected in a suitable control circuit not shown, energized by the proper source of voltage. When the coil 106 of said electromagnet is energized, the armature 113 is drawn down to overlie the pole faces 114 and as previously brought out. This, as previously stated, operates the toggle linkage 50 and closes the switch 10. Upon de-energization of the electromagnet 70 springs 91 and 92 return the parts to normal open position.

The advantages of the invention are manifest. Currents of high value may be handled by breaking the contacts in a vacuum. A minimum amount of arcing occurs, and minimum deterioration of the contacts results with the invention disclosed. Suitable spring pressure is applied to the contacts to provide the desired pressure during flow of current. Upon de-energization of the electromagnet, spring action returns the movable contactor into normal position. The springs for procuring the desired results are located exteriorly of the switch so that the same can be changed or altered without taking the switch apart.

Changes in the specific form of the invention, as herein described, may be made within the scope of what is claimed without departing from the spirit of the invention.

Having described the invention, what is claimed as new and desired to be protected by Letters Patent is:

1. In a switch mechanism having an evacuated housing, a fixed contactor therein extending through said housing, a movable contactor therein and extending through said housing and movable toward and from the fixed contactor, the atmospheric pressure urging said movable contact toward said movable contact, the combination of:

(a) a toggle linkage comprising two normally angularly disposed arms,

(b) pivot means between said arms,

(c) a link pivoted to said pivot means,

(d) actuating means for imparting longitudinal movement to said links tending to bring said arms into alignment,

(e) pivot means between one of said arms and a part carried by said housing and resisting movement of said second named pivot means away from said first named pivot means,

(f) interconnecting means fixed relative to said moveable contactor and connected to the other arm, said interconnecting being (g) cup shaped in form and having (h) a cylindrical (i) an end wall, and

(j) a flange extending outwardly from the other end of said cylindrical wall,

(k) resilient means acting between said interconnecting means and a part fixed relative to said housing and urging said movable contactor away from said fixed contactor and,

(l) resilient means acting between said movable contactor and said second named arm and applying pressure between said contactors as the arms are moved toward alignment.

2. The combination according to claim 1 in which:

(a) said first named resilient means engages said flange and a shoulder fixed relative to said housing and,

(b) said second resilient means engages the end wall of said interconnecting means and a part carried by said second named arm.

3. The combination according to claim 2 in which:

(a) said second named resilient means engages the end wall of said inter-connecting means and a slider slidable in said connecting means and pivoted to said second named arm.

4. In combination:

(a) a wheel supported truck having,

(b) a base, and

(c) uprights at the ends of said base,

((1) insulators extending upwardly from and supported on said uprights,

(e) an evacuated elongated housing,

(f) contactors disposed within said housing,

(g) an elongated support attached to and forming a continuation of said housing,

(h) means attaching said housing and support to said insulators,

(i) a toggle linkage carried by said support and moving one of said contactors relative to another there of,

(j) an electromagnet mounted on said base and hav- (k) a movable armature and,

(l) a link pivoted to said toggle linkage and operated by said armature.

References Cited UNITED STATES PATENTS Hauser 335173 Lester et al. 200114 Miller 200-114 Hollyday 335 26 Peek et a1. 335166 May et a1 200153 10 BERNARD A. GILHEANY, Primazy Examiner.

GEORGE HARRIS, JR., Examiner. H. BROOME, Assistant Examiner.