US2055707A - Electric circuit timing apparatus - Google Patents

Description

Sept 29, 1936. I

C. H. RIPPL ELECTRIC CIRCUIT TIMING APPARATUS Filed Jan. 28, 1935 INVENTOR.

Charles H Fifi b]. x 4 1 61 0 -AT'I'ORNEY.

Patented Sept". 29, 1936 UNITED STATES- ELECTRIC CIRCUIT TIMING APPARATUS Charles H. Itippl, Cleveland, Ohio, assignor to The Clark Controller Company, Cleveland,

Ohio, a corporation of Ohio Application January 28, 1935, Serial No. 3,880

6 Claims.

This invention relates to electric systems and apparatus of the class in which a time interval producing means maintains a predetermined condition of an electric circuit for a predetermined interval of time.

Among the many uses to which my invention may be applied is to the control of the duration of the flow of electric current used in making an electric weld.

It is among the objects of my invention: To provide an improved electric system and apparatus for maintaining a predetermined condition of an electric circuit "for a predetermined time interval;

To provide an improved electric system and apparatus whereby a predetermined electric circuit condition may be initiated at will by an operator and automatically continued in said condition for a predetermined time interval, and then be restored, independently of the operator;

To provide an improved electric switch mechanism whereby an electric circuit may be closed at will by an operator and the running of a time interval initiated thereby, and whereby at the end of the time interval the circuit may be opened automatically;

To provide an electric system andapparatus having control means actuable by anoperator to effect the closing of an electric circuit and to initiate the running of a predetermined time interval and to interrupt the circuit at the end of the time interval, and having improved means to prevent closing of the circuit again until after restoration of the control means by the operator.

Other objects will be apparent to those skilled in the art to which my invention appertains.

My invention is fully disclosed in the following description taken in connection with the accompanying drawing, in which:

Fig. 1 is a diagram of electrical circuits and apparatus illustrating one embodiment of my invention in a control system;

Fig. 2 is a sectional view of an actual apparatus illustrated diagrammatically and in simplified form in Fig. l;

Fig. 3 is a cross-sectional view taken approximately from the plane 3-3 of Fig. 2;

Fig. 4 is an elevational view taken from the plane 4-4 of Fig. 2.

Referring to the drawing, I have shown at I generally an electro-magnetic switch comprising a winding 2 and=an armature or plunger 3, movable switch arms 4 and 5 engageable respectively with stationary contacts 66 and 1-1 when the winding 2 is energized and the plunger 3 elevated.

A stem 8 connected to the plunger 3 to be lifted thereby is pivotally connected at its lower end to an arm 9 by having pivot connection with a pin ID on the arm 9. Vertical movements of the stem 8, by oscillatingthe arm 9, oscillate a shaft I I, the 5 oscillatory movements of which are communicated to a mechanism switch arm I2 through a time interval producing mechanism, omitted from Fig. 1 to simplify the diagram but shown in detail in the other figures of the drawing; the mechanism operating to move the-switch arm l2 to engage a stationary'contact l3 a predetermined adjustable time interval after the upward movement of the stem 8 caused by energization of the winding '2, and to disengage the arm I2 from the contact l3 upon downward movement of the stem 8 following de-energization of the winding 2.

Indicated generally at I4 is an electro-magnetlc relay comprising a winding I5, an armature or plunger I 6, a movable switch arm I! normally disengaged from a pair of contacts I8I8, and a movable switch arm I9 normally engaged with a pair of contacts 202Il,.the contacts |8--l8 being engageable and the contacts 2ll20 being disengageable by their respective switch arms I! and I9 upon elevation of the plunger l6 when the winding I5 is energized.

Control current from a supply main 2| flows, under the control of a manually operable switch 22, by a wire 23 through the normally closed contacts 20l 92II and by a wire 24 to and through the winding 2 and thence back to the supply by a main 25. Current may also flow from the main 2| under the control of the manual switch 22 by the wire 23 and by a wire 26 through the contacts I2-I3 when closed and thence by wire 21 to and through the winding I5 and back to the supply main 2".

When the relay I4 has been operated, current may flow under the control of the manually operable switch 22 by the wire 23 and through the contacts I8I8 to the winding l5, thus providing a holding or maintaining circuit for the winding I5 under the control of the manually operable switch 22.

In the embodiment of my invention illustrated,

. the main switch I controls the current from a To supply the welding-current for a predetermined time interval only, the operator closes the manually operable switch 22 which for convenience may be of the treadle type, and holds it closed, regardless of the time interval desired. Current then flows through the switch 22 and contacts 29-29 of the relay I4 through the-winding 2 of the magnetic switch I back to the main 25 whereupon the switch I operates, moving its switch arms 4 and I to closed switch positions, whereupon current from the main 29 flows to the transformer 29-39 and initiates a flow of welding current to the welding apparatus.

Upon elevation of the plunger 3 of the switch I to close its contacts as just described, the stem 9 sets into actionmechanism to be more fully described to initiate the running of a predetermined time interval. At the end of that interval, the switch arm I2 will engage the contact I3 and thereupon current will immediately flow through the manually operable switch 22, by contacts I2I3 to energize the winding I5 and thence back to the main 25, causing the relay I4 to instantly operate to break the circuit of the winding 2 on its contacts 29-20 and to'establish on its contacts I9'I9 a maintaining circuit for itself to maintain the winding I5 energized.

The opening of the contacts'20-2Il causes the switch I to open its contacts and discontinue the supply of the welding current which has been flowing for the predetermined time interval only.

The operator may now remove his control of the switch 22, allowing it to open, or opening it, whereupon the relay I4 will be restored, opening of the switch 22 breaking the maintaining circui above described for the winding I5.

By .this mode of operation above described, it will be observed that the operator, to produce a flow of current for a predetermined time interval, has only to close theswitch 22; and that thereby only a single impulse or single current flow of predetermined time interval can occur without precautionary operation by the operator, because after the flow of current has occurred and been stoppedpthe apparatus cannot repeat its cycle so long as the operator holds the switch 22 closed. To restore the apparatus or another cycle, the operator has only to momentarily open the switch 22, or open it and leave it open.

In practice, therefore, where welds are to be made rapidly one after the other, the operator may hold the switch 22 closed, for example by his foot, and to make each weld he has only to momentarily open the switch 22 and then close it again to produce a current flow for each weld. Or, if the welds are to be made less frequently, the operator can for each weld close the switch 22 and hold it closed until the weld is com leted and then allow the switch to open.

The mechanism for operating the switch arm I2 to engage the contact I3 at the end of a predetermined interval after operation of the switch I will now be described in a preferred embodimentin connection with Figs. 2 to 4 inclusive.

A shaft II is mounted to rotatably oscillate in a pair of spaced bearings 32 and 33 and adjacent the bearing 32 has secured rigidly thereto the arm 9 carrying the pivot pin above referred to, to which pin the stem 8 of the switch I is A second arm 34 is rigidly secured to the shaft 3|, preferably by a pin 35 in a hub 36 on the arm, and the outer end of the arm 34 has a pin 31 extending therefrom generally parallel to the shaft II. A sleeve 38 rotatable on the shaft II has rigidly secured thereto the inner element 39 of a clutch, the inner clutch element 39 having rigidly secured thereto an arm I2. A coiled helical spring 49 wound around the hub 39 and an inner end portion of the sleeve 39 has one free end 4I thereof overlapping the pin 31 and the other free end 42 thereof overlapping the arm I2,

the arrangement of the parts and spring being 10 such that, as illustrated, upon rocking the arm 34 toward the observer, the spring 49 will be put under increased tension and will apply the tension thereof through the free end 42 to the arm I2, exerting resilient torque thereon to move it 15 toward the observer as viewed in Fig. 2.

The inner clutch element 39 cooperates with an outer clutch element 43 provided with an inwardly facing cylindrical clutch surface 44, and

the inner clutch element 39 has a plurality of 30 balls 45 disposed in recesses 49 and constantly constrained by springs 41 to move toward a small end of the recess 49.

This clutch construction is generally well known and without further description it is believed to be clear that if the inner clutch element 39 is rotated, counter-clockwise as viewed in Fig. 3, the balls 45 will effect a wedging engagement between the cylindrical face 44 of the outer clutch element and the walls of the recesses 49 of the inner clutch element to lock the clutch elements together, but that if the inner clutch element 39 is rotated clockwise as viewed in Fig. 3, the balls will be moved toward the larger end of the recesses 46 and disengage the clutch elements.

The outer clutch element 43 is rotatably mounted on the sleeve 39, and a gear 49 is secured to the clutch element 43 and rotates therewith and meshes its teeth with a pinion 49 on a shaft 59, the pinion 49 being connected to a gear II which meshes its teeth with a pinion 52 rigidly connected to a shaft 53 to which is also connected a fan 54 of the vaned type.

A stop 55 of any suitable construction may be provided to stop the downward oscillatory movement of the arm 9 and therefore of the stem 9; and the pin 31 overlaps a portion of the arm I2 as shown at 56, Fig. 2 and the spring 49 is formed so that the free ends H and 42 maintain the pin. 55 normally in engagement with the arm I2. By this construction, when the parts are in their normal positions and the oscillatory arm 9 rests upon the stop 55, a normal predetermined position will thereby be determined for the arm I2. The arm I2 is provided with a resiliently supported contact 51 and spaced therefrom is a stationary contact l3 supported on a. suitably disposed bracket 59 and rendered adjustable toward and from the contact 51 by being mounted on a stud 90 threaded in the bracket 59, a lock nut 9| being provided to fix the adjusted position of the contact I3.

In the operation of the mechanism of Figs. 2 to 4 inclusive taken in connection with Fig. 1, when the electromagnetic switch I is energized. its plunger 3 is instantly drawn upwardly for its full stroke as is common with such switches to instantly close the contacts 5 and I. The oscillatory arm 9 is therefore quickly moved to an angle of oscillation determined by the stroke of the stem 8. This movement likewise oscillates the arm 34 causing the pin 31 thereof to leave the arm I2 and to put additional tension in the spring 40 by means of its free end 4| and applying scribed and to turn the gear 48. The motion of the gear 48. is transmitted to the fan 54 through the step ungear train, rotating thefair ata high velocityand causing thev friction thereof with the air to retard; the movement of the. fan 54 thereby causing the. gear, 4.8 and the arm l2 clutched thereto to move with a retarded movement. At the end of the time interval, this retarded movement bringsthe contact 5T into engagement with the contact l3.

Upon engagement of the contact l3, the relay I4 is operated as described in connection with Fig.. 11,. de-energizing the winding of the switch i and causing the plunger, thereof and the oscillatory arm. 9 to be restored, the arm 9 into engagement with the stop 55. This movement moves the pin 31 away from the observer as viewed in Fig. 2 and into engagement with the arm l2, and positively moving it along with the gear 48 and the train of gears may stand still.

without rotating to be in' readiness for the running of another time interval.

At all times, in order to insure that the gear 4! and the train of gears associated therewith may not continue to move or drift, a brake device is provided to bring them to rest comprising a brake shoe 62 engaging the outer cylindrical surface 63 of the outer clutch element 43 and is held in resilient engagement therewith by a spring 64 secured at one end to'the brake shoe 62 and at the other end secured to the arm l2. The upward stroke of the stem 8 may, if desired, be definitely limited by a stop ,65 engageable by the end of a pin 66 on the plunger 3; and both of the stops, '5 and 55, may be adjustable as indicated.

As will be clear from the foregoing description, the time interval will be determined by the distance from the contact 51 when in its normal position to the contact l3, and the time interval therefore may be adjusted by adjusting the screw 60 to move the contact I3 toward or from the contact 51.

While I have shown a control switch 22 of the spring-opened manually closable iorm, it will be obvious that it may be operated to close and open its contacts by other means, for example by -mechanisrn means or by electromagnetic means.

My invention is not limited to the exact details of construction illustrated and described. Changes and modifications may be made therein and my invention comprehends all such changes and modifications embraced within the scope of the appended claims.

I claim:

1. In an electric system and apparatus, a circuit to be controlled, a first electromagnetically operable switch comprising a winding and a movable member movable through a predetermined range of movement and controlling the circuit, a control switch, a source of cont ol current supply, a second electromagnetically operable switch having a windingand having normally open con tacts connected to the supply in series with its own winding and with the control switch contacts and having normally closed contacts connected to the supply in series with the winding of the first switch and with the control switch contacts,- a delayed operation switch mechanism comprising mechanism contacts and energy storage means in which energy is stored by movement of the first switch member through its range of movement and mechanically operable to initiate the running off apredetermined time interval by movement of the movable member of the first switch, and at the end of' the time interval closing the mechanism contacts, the mechanism contacts being "connected to the supply in series with the second switch winding and with the control switch con tacts, whereby upon closing the control switch contacts the first switch is caused to operate and start the time interval, and at the end of the time interval the second switch is caused to operate to deenergize the first switch and maintain itself operated so long as the control'switch contacts are maintained closed, and means to vary the time interval by varying the range of movement of the switch member to vary the amount of energy stored thereby.

2. In an electric system and apparatus, a circuit to be controlled, a first electromagnetic'ally operable switch comprising a winding and a movable member and controlling the circuit, the movable member being movable from a switch open to a switch closed position, means to stop the switch in a predetermined open position, a con- .trol switch having normally open contacts, ea

source of control current supply, a second electromagnetically operable switch having a wind ing and having normally open contacts connected to the supply in series with its own winding and with the control switch contacts and having normally closed contacts connected to the supply in series with the winding of the first switch and with the control switch contacts, a delayed operation switch mechanism comprising mechanism contacts and comprising energy storage means in which energy is stored by movement of the switch movable member from its stopped to its closed position, the mechanism being operable to initiate the running of a predetermined time interval by movement of the movable member, and at the end of the time interval closing the mechanism contacts, the mechanism contacts being connected to the supply in series with the second switch winding and with the control switch contacts whereby upon closing the control switch contacts the first switch is caused to operate and start the time interval, and at the end of the time interval the second switch is caused to operate to deenergize the first switch and maintain itself operated so long as the control switch contacts are maintained closed, and means to vary the stopped open position of the first'switch to vary the amount of energy stored in the mechanism by operation of the switch member to correspondingly adjustably vary the time interval.

3. In an electric system and apparatus, a circuit to be controlled, a first electro-magnetically operable switch comprising a winding and a movable member and controlling the circuit, the movable member being movable irom a switch open to a switch closed position, a control switch having normally open contactsja source of control current supply, a second electro-magnetically operable switch having a winding and having normally open contacts connected to the supply in series with its own winding and with the control switch contacts and having normally closed contacts connected to the supply in series with the winding of the firstswitch and with the control switch contacts, a delayed operation switch mechanism comprising mechanism contacts and comprising energy storage means in which energy is i the control switch contacts whereby upon closing the control switch contacts the first switch is caused to operate and start the time interval, and at the end of the time interval the'second switch iscaused to dperate to deenergize the first switch and maintain itseli' operated so long as the control switch contacts are maintained closed, and means to vary the time interval by adjustably varying the amount oi'energy dissipated from the storage means.

4. In an electric system and apparatus, a circuit to be controlled, 8. first electromagnetically operable switch comprising a winding and a movable membermovable through a predetermined range of movement and controlling the circuit, a control switch, a source of control current supply, a second electromagnetically operable switch having a winding and having normally open contacts connected to the supply and controlling its own winding jointly with the control switch contacts, and having normally closed contacts connected to the supply and controlling the winding of the first switch jointly with the control switch contacts, a delayed operation switch mechanism comprising mechanism contacts and mechanical energy storage means in which energy is stored by movement of the first switch movable member through its range of movement and mechanically operable to initiate the running of a predetermined time interval by movement 01' the movable member of the first switch and at the end of the time interval operating the mechanism contacts, the mechanism contacts being connected to the supply and controlling the secondswitch winding jointly with the control switch contacts whereby upon operatmember to vary the amount of energy stored thereby.

5. In an electric system and apparatus, a circult to be controlled, a first electromagnetically operable switch comprising a winding and a movable member and controlling the circuit, the movable member being movable from a switch open to a switch closed position, means to stop the switch in a predetermined open position, a control switch, a source of control current supply, a second electromagnetically operable switch having a winding and having normally open contacts connected to the supply and controlling its own winding Jointly with the control switch contacts and 5 having normally closed contacts connected to the supply and controlling the winding of the first switch jointly with the control switch contacts, a

delayed operation switch mechanism comprising the control switch contacts the first switch is caused to operate and start the time interval, and at the end oi the time interval the second switch is caused to operate to deenergize the first switch and maintain itseli' operated so long as the control switch contacts are maintained operated, and means to vary the stopped open position of the first switch to vary the amount of energy stored in the mechanism by operation of the switch member to correspondingly adjustably vary the time interval.

6. In an electric system and apparatus, a circuit to be controlled, a first electro-magnetically operable switch comprising a winding and a movable member and controlling the circuit, the movable member being movable from a switch open to a switch closed position, a control switch, a source of control current supply, a second electro-magnetic'ally operable switch having a winding and having normally open contacts connected to the supply and controlling its own winding jointly with the control switch contacts and having normally close'd contacts connected to the supply and controlling the winding of the first switch jointly with the control switch contacts, a delayed operation switch mechanism comprising mechanism contacts and comprising energy storage means in which energy is stored by movement of the switch movable member from its open to its closed position, the mechanism being operable to initiate the running of a time interval by movement of the movable member, and to maintain the running of the interval for a predetermined time by dissipation of stored energy, and at the end 01' the time interval closing the mechanism contacts, the mechanism contacts being connected to the supply and controlling the second switch winding jointly with the control switch contacts whereby upon operating the control switch contacts the first switch is caused to operate and start the time interval, and at the end of the time interval the second switch is caused to operate to deenergize the first switch and maintain itself operated so long as the control switch contacts are maintained operated, and means to vary the time interval by adjustably varying the amount of energy dissipated from the storage means.

- CHARLES H. RIPPL.

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