US1843937A - Electric switch - Google Patents

Description

Feb. 9, 1932. E. J. VON HENKE 1,843,937

ELECTRIC SWITCH Filed Feb. 9, 1926 2 Sheets-Sheet l @JXQVM MTOR.

BYWrM i ATTORNEYS.

Fel a. 9, 1932. E. J. VON HENKE 1,843,937

ELECTRIC SWITCH Filed Feb. 19, 1926 2 SheetsSheet 2 %Z;. Z. I 500 INVENT BY M A TTORNEYJ.

- EDMUND J. VON v I FUfSION CORPORATION, OF CHICAGQ ILLINOIS, A

Patented Feb. 9, 1932 PATENT}. OFFICE Y' UNITED STTETS HENKE, or zcn'rcaeo, rLnmois, ASSIGNOR 'ro AMERICAN ELECTRIC CORPORATION or ILLINOIS ELECTRIG' SWITCH Application filed February 19, 1926. Serial No; 89,269.

My invention relates to welding machines and particularly to the means for actuating the movable electrode and applying welding current and pressure to the parts being welded. My invention is particularly applicable to spot welding machines and is useful in the welding of work of varying thicknesses. By the use .of my invention uniform results are secured without the necessity of frequent adjustment as is necessary with machines as ordinarily constructed when employed upon work of different thicknesses.

My invention will be better understood by reading the following description taken in connection with the accompanying drawings forming a part thereof and illustrating one embodiment of the invention, and in which- Fig. 1 is a sectional elevation of a machine embodying my invention;

r Fig. 2 is a side elevation of the switching means for controlling the welding circuit; 'Fig. 3 is a side elevation of the switch shown in Fig. 2, with certain parts in section;

Fig. 4 is a view on the line IVIV. of Fig.2; and I r Fig. 5 is a view on the line V V of Fig. 3.

Referring to the drawings, the machine comprises a casing 1 in which is placed the transformer 2 and upon which is mounted a pivoted frame 3 carrying the movable electrode 4. A stationary electrode 5 is carried in the holder 6 which is adjustable in the ordinary way. A treadle 7 is connected through levers 8, 9 and lO with the operating rod 11 which inturn is operably connected with one end of the frame 3. Connected between the lever 10 and rod 11 is the switching mechanism which is illustrated in detail in Figs. 2 to 5, inclusive. A manhole is provided in the side of the casing 1 and is normally closed by the cover 12. A cover 13 normally closes an opening in the front of the casing, as shown in Fig. 1.

WVith the exception of the switch above referred to the parts mentioned may be of any desired design and construction, and per se do not constitute any material part of my invention. I

, I will now describe'the switchwhich is con- .scoped onto :member 33 extends. able relative to the members 31 and 32 and is .controlled by means which A contact disk 34 is loosely carried by tried on abridge 37.

nected between the lever 10 and rod 11 and which is illustrated in Figs. 2 to 5, inclusive. .The switch comprises frame members 14 and 15. The frame member14 has two side 7 A threaded rod 24 passes upwardly through an opening in the frame member 14 and is provided with a flange 25 at its upper end. A coupling 26 is screwed onto the lower threaded end of the rod 24 and an adjustable hand wheel 27 is screwed ontothe rod above the coupling. Collars 28 and 29 are placed around the rod 24 and a coil spring is telethe rod and has its ends in engagement with the collars 28 and 29. The compression on the spring 30 is controlled by the position of the hand wheel 27 on the rod 24. Normally this spring acts to hold the parts in the positions shown in Fig. 2. The members 31 and 32 are bolted ontofbut insulated from the flange 25 and provided with an opening through which the switch The member 33 is movwill be explained later. the member 33 and is adapted to engage the contact posts 35 and 36, as will be explained later. The contact posts 35 and 36 are car- This bridge consists of two parallel rods 38 and 39, the ends of which are carried by the frame member 15, as shown in Fig. 4. Members 40 are provided at one end with an opening through which the rod 39 passes and with an open-ended slot in the other end which partially engages and surrounds the rod 38. The screw bolt 41 when tightened causes the member 40 to grip the rod 39, as shown in Fig. 5. The members 40 carry the Contact posts 35 and 36 and because and 17 provided with bifurcated n placed, or similar posts may be substituted and the machine continued in operation while the old posts are bein refinished.

lVhen it is desiredL to renew or dress the electrodes the wing nuts 22 and 23 are loos encd and the frame members 14 and 15 separated. The removal of the member 14 carries with it the projection 14 (in the form of a screw-head, as shown). This allows the rod 39 to drop down out of the slot in the frame member 15. As soon as the rod 39 is out of the slot the cross members 40 may be removed from the rod 38 and the bridge removed from the frame and another substitute ed or the contacts dressed and the same bridge replaced.

The switch member 33 is provided on one side with notches 42 and 43. A detent 44 is mounted in a part of the frame mannber 14 and has one end shaped to fit into the notches 42 and 43. The detent 44 is movable in the opening in the frame member 14 and a coiled spring 45 is placed behind the detent 44 and acts to press the same to the right into the position shown in Figs. 3 and 5. The mem ber 33 also carries a rod 46 which passes therethrough and the ends of which are adapted to engage stops 47 on tne sides 16 and 17 of the frame member 14. The members 31 and 32 are provided with elongated openings 48 through which the pin 46 eX- tends and by reason of which the pin is permitted to move up and down withthe switch member33', as will be explained later.

In one method of operation of the device above described, it is desired that the electrodes 4 and 5 shall engage the work and clamp the same securely before the welding current is passed through the work; that a certain predetermined pressure he applied to the parts to be welded prior to and during the passage of the welding current; that the welding current be automatically supplied to the welding electrodes while under pressure; that the welding current be automatically cut off from the electrodes while the, pressure is maintained; and that means be provided for increasing the pressure at the point of weld after the welding current has been discontinued, but while the parts are still in plastic condition. This finally increased pressure aids materially in effecting a good weld. The 0 oration above described may be efiecte by the mechanism heretofore described in the following man ner: The work is placed between the electrodes and the treadle 7 pressed down. This will cause the lever 10 to move upwardly thus moving the switch mechanism and the rod 11, which in turn, causes the movable electrode 4 to engage the work. As the treadle 7 is pressed down further the spring 30 is placed under further compression and the rod 24 moved upwardly carrying with it the members 31 and 32, the switch'33 and the 'treadle 7 thus disk 34. The switch member 33 and disk 34 are moved with the members 31 and 32 because the detent 44 is in position in the notch 43 and thus acts to carry the members 33 and 34 upwardly until they engage the contact posts 35 and 36. As soon as the disk 34 engages the posts 35 and 36 this upward movement is arrested and upon the further downward movement of the treadle 7 the members 31 and 32 are moved upwardly and a slight movement is thereby caused between the members 31 and 32 and the member 33. This movement causes the detent 44 to be pressed outwardly by the inclined edge of the notch 43 engaging the top edge of the detent. As

this movement continues the point of the detent passes over the point 49 between the notches 42 and 43 and the spring 45 then pushes the detent to the right as viewed in Fig. 5, thus causing the switch member 33 and disk 34 to snap away from the contact posts 35 and 36, thus opening the welding circuit. Shortly after this snap operation the mem ber 50, which is rigidly attached to the rod 24, engages a shoulder 51 on the frame 14, thus producing a rigid connection from the lever 10 to the rod 11 through the frame of the switch. Any pressure that is thereafter placed upon the treadle 7 is therefore transmitted directly through the mechanism described to the electrode 4 and thus to the work.

Upon the completion of the weld it becomes necessary that the parts be placed in the original positions so that another weld may be made. This is accomplished by the operator decreasing the pressure on the permitting the, lever 10, rod 24, members 31 and 32, 33 and 34 to drop downwardly. As these parts fall the rod 46 which moves with the member 33 engages the stops 47 and causes the detent 44 to be moved from the notch 42 back to the notch 43, thus restoring the parts to their original positions, whereupon the apparatus is in condition for another weld which may be executed as above described.

It is often desired that the automatic opening feature ofthe switch be nullified. In such case the member 52, which is placed on the frame 14 is actuated by'a knurled head 53 on the upper end of a rod 54, to which the member 52 is attached. The member 52 is eccentric with respect to the rod 54 and when in the position shown in Fig. 5 is not engaged V by the member 50. When turned, however,

the member 52 is placed in the path of the member 50 so that these two parts engage beforethe detent 44 snaps from the notch 43 into the notch 42. There will be a slight move mentbetween-the member 33 and the members 31 and 32 under these circumstances but this movement will not be sufiicient in amount to cause the snap action of the switch. All of the other described features of the operation of the mechanism will be secured, however, except that of automatically opening the switch.

As is well known, after the machine has been operated for a great many times the disk 34 and/or the contact posts 35 and 36 become pitted or roughened because of the are produced by the breaking of the circuit. It therefore becomes desirable to dress these surfaces at intervals in order to secure the best operation from the machines. operation is facilitated because of the construction shown. That is to say, by removing the cover 12 on the machine and loosening the winged nuts 22 and 23 and removing the bolts and 21 from the lugs 18 and 19, the lower part of the switch may be rotated around'the coupling 26 so that the disk 34 comes into a convenient place for either removing or redressing the same. At the same time because of the removable mounting of the terminal posts 35 and 36, they may be readily removed from the upper part of the switch and either redressed or removed and new ones substituted therefor. This arrangement greatly facilitates the maintenance of the machine in operative condition an thereby increases their efiiciency.

While I have shown and described in detail one form of my invention, I desire that it be understood that I am not limited to the exact arrangement shown and described, as many changes may be made in details of construction without departing from the spirit I of my invention.

I claim:

1. A switch comprising two frame members, readily removable means securing said members together, removable contacts rigidly mounted on one part and a movable contact carried by the other part of said frame, said contacts facing along a plane adjacent the plane of division of said frame parts whereby said contacts may be renewed or redressed.

2. A switch comprising two frame members removably fastened together, and conbers, said mountingincluding a bridge having one end held by an open notch construction and theother end held by an open notch construction at 90 from said first notch construction, means for holding said bridge in said notches, "and a movable contact on the other frame member cooperating with said fixed contact.

6. In an electrical switch, the combination of two frame members, means for holding said members in readily detachable relation to each other, a contact removably mounted in one of said members, said mounting including a bridge having a slot therein,

slot in the bridge, bridge in said slots,

d on the other frame member.

7. In an electrical switch, the combination of two separate frame members, means for holding said members together and readily detaching the same, fixed contacts mounted .in one of said members, said mounting 1ncluding a member notched at one end and engaging a member on said frame member, and means on the other end of said notched member for holding said member in a notch in the frame at 90 to the first-mentioned notch.

EDMUND J. VON HENKE.

tacts carried by one ofsaid members, a bridge carrying said contacts and means whereby said bridge may be removed upon the separation of said switch frame members.

8. In an electrical switch, the combination of a frame, contacts mounted therein, said mounting including a member notched at one end and adapted to engage a projection on said frame and a notch in the frame at 90 to the normal position of said first notch, and means on the switch frame for holding said member in said second notch.

4:. In an electrical switch, the combination of a frame, a fixed contact mounted in said frame, said mounting including a contact carrying member, a notch in one end thereof adapted to engage a projection on the frame, a notch in the frame opening at 90 to the and means on the frame for a slot in one of the frame members at to the

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