US1954976A - Air switch - Google Patents

Description

April 17, 1934. F. L. AIME AIR SWITCH Filed April 22. 19:0

3 Sheets-Sheet l FRANK L.AIME

F. L. AIME AIR SWITCH pril. 17, 1934.

3 Sheets-Shet 2 Filed April 22. 1930 a Wm A M Wu A R F mwE April 17, 1934. F. L. AIME AIR SWITCH Filed April 22, 1930 3 Sheets-Sheet 3 FRANK L. AIM

Patented Apr. 17, 1934 UNITED STATES PATENT OFFICE AIR SWITCH Frank L. Aime, Yonkers, N. Y. Application April 22, 1930, Serial No. 446,219 7 Claims. (Cl. 200-89) The invention relates in general to electric 10 which is mounted upon a suitable support as switches, and more particularly to air break is well known in the art. The switch further switches. comprises a stationary arm 11, an operating mem- An object of the invention is to provide an ber 12, a movable arm 13, and an insulator sup- 5 air switch having means for automatically opport 14.

crating to extinguish the arc. The stationary arm 11 comprises an insulator Another object of the invention is to provide P 21 p Wh ch is moun ed a S table inan air break switch having means for causing the sulator such as a petticoat i sula Which, pressure generated by the arc to assist in exn u supp t a a 23 Which p t e tinguishing it. socket contact terminal 24. Another object of the invention is to provide T movab e a m 3 omprises an insulator an air break switch having devices for causing a pi 5 Supporting a suitable insulator Which current of gases to flow longitudinally of the arc n u pp an a 3 wh ch Carries the to assist in extinguishing the arc. plug terminal 33 of the switch. The insulator 15 Another object of the invention is to provide an pi 25 is mo p a horizontal Shaft av air break switch having either manual or autoa squared d 30 p Which is also mounted p matic trip-free disconnecting means, or both, arms 26 and 2'7 having set screws 28 and 29 for Another object of the invention is to provide mi i g the Positions o th movab e arm 13. It an air break switch with an arc extinguishing will be understood that, as explained he ina t 20 device, which assists in moving the switch mechthe squared end 30 may b engaged y a suitable anism. operating mechanism to throw the movable arm Another object of the invention is to provide 13 from a closed to open position, or vice versa. an air break switch, which is simple, strong, and Referring now to the switch terminals and the durable in construction, and effective in operad v es fo extinguishing the a the terminal 25 tion. 24 is shown in the form of a conventional socket, Other objects will be apparent from the followwhich is well-known in the art, and is mounted ing description and claimswhen considered with in a collar 35 at the upper end of arm 23. The the accompanying drawings, in which contact 33 is in form of a plug, which seats Figure 1 is a side elevation, partly in section, within the socket 24 and has a removable tip 34 30 of a preferred form; (Figure 7). The terminal 33 has a pair of slots Figures 2 and 3 are details illustrating the op- 44 in its end, which seats between ears 46 on the eration of an automatic over-load release; end of arm 32. A plurality of bo ts 45 pass through Figure 4 illustrates the operating parts in open the ears 46 and slots 44 to adjustably clamp the position; terminal 33 in semifixed position. Surrounding 35 Figure 5 is a section on the line 5-5 of Figthe connection between terminal 33 and arm 32 ure 2; is a shroud 47.

Figure 6 is a section on the line 6-6 of Fig- Surrounding the contacts is body or chamber ure 1; 38 made of suitable insulating material, such as Figure '7 is a detail illustrating the plug contact porcelain, or of a plastic insulating material, such 40 of the switch; as bakelite. The housing 38 comprises a suit- Figure 8 is a section on the line 8-8 of Figable enlarged Portion e tubule! P t n 9, ure 7; v and a tubular portion 41. The tubular portion Figure 9 illustrates a modified form of the in- 39 surrounds and supports the terminal 24, and vention; and in turn is supported by the collar 35. Suitable 45 Figure 10 is a section on the line 10-10 of Figm an 37 u as cement m be in rpo ed beure 9. tween terminal 24 and tubular portion 39 and In the following description and in the claims suitable means 36 such as felt may be interposed parts will be identified by specific names for conbetween tubular portion 39 and collar 35. A petvenience, but they are intended to be as generic ticoat 43 is mounted upon the tubular portion 50 in ther application to similar parts as the art 41 for increasing the creepage distance. The will permit. mouth of the tubular portion 41 is shown at a Like reference characters denote like parts in suitable angle to the vertical to substantially prethe several figures of the drawings. vent the entrance of rain, snow, sleet, dirt, etc.,

Referring now to the drawings, and more parinto the tubular portion 41 and into the enlarged ticularly to Figure 1, the switch comprises a base portion 40. Preferably the mouth is provided 2 with a depending lip 42. It will be understood that the movable contact 33 and the parts of the housing 38 and of the stationary terminal 24, which cooperate with the movable terminal 33, are laid out on the arc of the circle whose center is the shaft 30.

The operating insulator 12 comprises an insulator pin 51 having a projection passing through the base 10. It will be understood that the projecting shaft 50 passes through to suitable operating mechanism (not shown) for rotating it together with the insulator pin 51. Mounted upon the pin 51 is a suitable insulator 52 having a plate 53 mounted thereon, which carries a crank pin 62. Secured to crank pin 62 is a link 54, which is connected to another link 56 by a suitable restricted universal joint 55. The link 56 is provided with a catch 57 pivoted by pivot 58, and resting upon a pin 59 (see also Figures 2, 3, and 4). The catch 57 has an abutment 60, which normally engages a pin 61 mounted upon arm 32.

Connected to the arm 32 by means of a bolt 68 (Fig. 6) is a guide member 67 supporting the arm or link 56. The link 56 has a stop member 66 mounted thereon, which cooperates with the guide 67 to assist in limiting the open position of the switch. However, arms 26 and 27 are the principal limiting means.

Pivoted to the cap on the insulator 31, by pivot 71, is a link 69 which is pivoted to link 70 by pivot 72, the link 70 being pivoted to the cap of insulator 77 by pivot 73, forming in effect a grasshopper mechanism, which supports a pigtail or flexible conductor 74, which connects with the line conductor and with the solenoid 78. The insulator 77 is mounted upon an insulator pin 76, which is supported by the base 10. If desired, in place of the line supporting insulator 14, a strain insulator may be used in which case the grasshopper mechanism will extend to the line side of the strain insulator, as is well-known in the art.

The solenoid 78 is mounted in suitable position above the cap of insulator 31 and has a plunger 80, which is adapted to engage the catch 57 to knock it up when overload flows through the line and the solenoid is actuated. This disengages the abutment 60 with the pin 61, and allows the switch J to be pulled to open position automatically by means of a spring mechanism hereinafter described.

Referring now to the spring opening mechanism the base 10 supports a pedestal 81 to which is pivoted a sleeve 82 enclosing a pair of coil springs 83 and 183. A stiff rod 84, which is pivoted to the insulator pin 25 by a pivot 85, has an abutment 184 disposed between the springs 83 and 183.

It will be understood that a suitable pigtail conductor 63 extends from the solenoid 78 to the terminal 33, and that a suitable pigtail conductor 64 extends from the contact 24 to the line 65, which is connected to the cap on insulator 22.

In the position shown in full lines in Figure 1, the switch is closed. To open the switch manually the shaft 50 may be rotated forcing the contact 33 out of closed position and allowing the spring 183 to assist in quickly pulling the movable contact 33 out of engagement with the stationary contact 24 to the position shown in dotted lines. If desired, the operating insulator and cooperating mechanism 12 may be omitted, and the movable arm 13 may be operated by engaging the squared end of shaft 30 directly by a suitable tool or mechanism.

In addition to manual opening of the switch, the switch may be opened automatically by the trip-free mechanism due to over-load. In this case the over-load current flowing through the line actuates the solenoid 78 causing the plunger to hit catch 57, which in turn causes disconnection between abutment 60 and pin 61 allowing the spring 183 to quickly pull the switch to open position.

It will be noted that the end of the terminal 24 is located approximately in the center of the sphere 40, and that the tubular portion 41 of the housing 38 fits rather snugly about the terminal 33. As the switch is opened either automatically or manually, it will be understood that the initial are caused by the separation of the tips of contacts 24 and 33 causes the reservoir of air and/ or gases held in enlarged portion 40 to suddenly heat up, tend to expand, and produces gas or gases under pressure. Due to the more or less snug fit between the contact 33 and tubular portion 41, the compressed gas or gases cannot escape readily, so it assists in forcing the movable contact 33 to open position, and at the same time creates a fiow of gas or gases longitudinally of the arc and through the neck or cylindrical portion 41 of housing 38, which assists in extinguishing the arc.

This assistance is accomplished in two or more ways acting either alone or in cooperation with one another: one by the action of the gas under pressure carrying with it as it blows out of the tubular portion 41, the ingredients therein such as metals of the electrodes in gaseous form which help to sustain the arc, thus ridding the chamber of materials which would normally assist in sustaining the arc; another by the process of the expansion of the gases as they leave the chamber or housing 38 cooling themselves and thereby serving to make it difiicult or impossible for the arc to be maintained or reformed; and coincidentally thereto by these gases escaping from the chamber 38 causing a partial vacuum in the chamber which action also makes it difiicult or impossible for the arc to be maintained or reformed and further by the partial vacuum thus formed requiring new and cooler air to flow into the chamber 38 to bring the pressure in it into a state of balance with that of the outside air, thus further hindering or preventing the maintenance or reforming of the arc.

Referring now to the modified form shown in Figures 9 and 10, the arc extinguishing housing is denoted by 91, and is of a similar construction to the housing 38 in Figure 1, except that it is laid out along a straight line instead of the arc of a circle. The socket contact is denoted by 93, and the plug contact by 92. The housing 91 carries the socket 93 in a manner similar to that described in connection with Figure 1, and the housing 91 is pivoted frictionally by the pivot 94 to a fitting 120 carried by the stationary arm 97. The arm 97 has the fitting 120 connected thereto by a pivot 96. The fitting 120 has a slot through which a bolt 98 passes into the arm 97 for adjustably positioning the fitting 126. The fitting 120 has a pair of adjustable stops 100 and 101 between which a finger 99 connected to the housing 91 is positioned. Surrounding the connection between the housing 91 and the arm 97 is a shroud 104.

The movable arm 111 has a pair of ears 116 between which is frictionally pivoted by pivot 115 a fitting 106. The fitting 106 carries a lug 109 located between a pair of adJustable stops 112 and 113 which cooperate with lug 109 to limit the movement thereof. Also mounted upon the pivot 115 is a second fitting having a corrugated surface 121, which interfits with a similar surface upon the fitting 106. The fitting 105 carries the contact 92 and is provided with a pair of bolts 107 disposed in a pair of slots 108 in the fitting 106. A shroud 114 surrounds the entire connection between the arm 111 and contact 92. It will be understood that the movable arm 111 moves about a center in a manner similar to the arm 13 in Figure 1.

The frictional pivots 94 and 115 have sufficient friction to hold the housing 91 and the contact 92 in any set position, but the friction is not sufficient to prevent the necessary pivotal movement for the contact 92 and housing 91 to engage and separate. It will be understood that the contact 92 and housing 91 must remain in line while they engage and separate. In other words, as the tip of the movable contact 92 leaves or enters the tip of the housing 91, the axes of these members must be in line. After the housing 91 and contact 92 separate completely, the axes of these members go out of line, the friction of pivots 94 and 115 holding the housing 91 and contact 92 in the same relative position to the arms 9'7 and 111 that they had when the tips of the housing 91 and contact 92 were separating.

So far as the operation of the arc extinguishing device is concerned it is the same in this modification as that described above in connection with Figure 1. The movable arm 11 may be moved manually or automatically by an overload mecha nism, in both cases the construction being similar to that described in connection with Figure 1.

While certain novel features of the invention have been shown and described and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes may be made by those skilled in the art without departing from the spirit of the invention.

What is claimed is:

1. In an air break switch, a base, a stationary insulator on said base carrying a stationary contact, a movable arm comprising a support pivoted to said base, an insulator on said support, a member carried by said insulator and carrying a movable contact, a second stationary insulator, a grasshopper mechanism connecting the line side of said second stationary insulator and said member, elastic means between said support and base normally assisting in carrying said movable arm to open position, means for operating said movable arm, said means comprising operating mechanism and a link extending to said member from said operating mechanism, a latch pivoted to said link and engaging an abutment on said member, a solenoid having a plunger and carried by said movable arm insulator, said solenoid being in series cooperation with the line conductor connecting said line and movable contact, said plunger being adapted to engage said latch.

2. In an air break switch, a base, a stationary insulator on said base carrying a stationary contact, a movable arm comprising a support pivoted to said base, an insulator on said support, a member carried by said insulator and carrying a movable contact, a second stationary insulator, a grasshopper mechanism connecting the line side of said second stationary insulator and said member, elastic means between said support and base normally carrying said movable arm to open position, means for operating said movable arm, said means comprising operating mechanism and a link extending to said member from said operating mechanism, a latch pivoted to said link and engaging an abutment on said member, a stop on said link to engage and limit the open position of said movable arm, a solenoid having a plunger and carried by said movable arm insulator, said solenoid being in series cooperation with the line conductor connecting said line and movable contact, said plunger being adapted to engage said latch.

3. In an air break switch, a base, a stationary insulator on said base carrying a stationary contact, a movable arm comprising a pin pivoted to said base, an insulator on said pin, a member carried by said insulator and carrying a movable contact, a second stationary insulator, a grasshopper mechanism connecting the line side of said second stationary insulator and said member, elastic means between said pin and base normally urging said movable arm to open position, an operating arm comprising a pin rotatably mounted on said base and an insulator carrying a crank pin, a link extending between said crank pin and said member, a latch pivoted to said link and engaging an abutment on said member, a stop on said link to engage and limit the open position of said movable arm, a solenoid having a plunger and carried by said movable arm insulator, said solenoid being in series cooperation with the line conductor connecting said line and movable contact, said plunger being adapted to engage said latch.

4. In an air break switch, a base, stationary insulator on said base carrying a stationary contact, a movable arm comprising a support pivoted to said base, an insulator on said support, a member carried by said insulator and carrying a movable contact, elastic means between said support and base normally carrying said movable arm to open position, and automatic trip and tripfree mechanism for operating said movable arm.

5. In an air break switch, a base, a stationary insulator on said base carrying a stationary contact, a movable arm comprising a pin pivoted to said base, an insulator on said pin, a member carried by said insulator and carrying a movable contact, elastic means between said pin and base normally carrying said movable arm to open position, means for operating said movable arm, said means comprising operating mechanism and a link extending to said member from said operating mechanism, a latch pivoted to said link and engaging an abutment on said member, a stop on said link to engage and limit the open position of said movable arm, a solenoid having a plunger and carried by said movable arm insulator, said solenoid being in series cooperation with the line conductor connecting the line and movable contact, said plunger being adapted to engage said latch.

6. In an air break switch, a base, a stationary insulator on said base carrying a stationary contact, a movable arm comprising a pin pivoted to said base, an insulator on said pin, a member carried by said insulator and carrying a movable contact, elastic means between said pin and base normally urging said movable arm to open position, an operating arm comprising a pin rotatably mounted on said base and an insulator l carrying a crank pin, a link extending between said crank pin and said member, a latch pivoted to said link and engaging an abutment on said member, a stop on said link to engage and limit the open position of said movable arm, a soleconditions for tripping the switch and allowing said yieldable means, assisted by the force due to the pressure generated by the arc in said housing, to open the switch, the said second contact separating a substantial distance from said housing and said first contact to provide sufficient air gap for the high tension and trip free means for closing the switch Without interfering with the action of said automatic tripping means.

FRANK L. AIME.

Images