US1903459A - Controlling apparatus - Google Patents

Description

April 11, 1933. E, T. JoHNssoN GONTROLLING APPARATUS Filed May 28, 1931 2 Sheets-Sheet l April 11, 1933; E. T. JoHNssoN CONTROLLING APPARATUS 2 Sheets-Skireet 2 Filed May 28, 1931 Patented Apr. 11, 1933 UNITED STATES EMIL T. JOHNSSON, F CHICAGO, ILLINOIS CONTROLLING APPARATUS Application led May 28, 1931.

This invention relates to controlling apparatus for controlling pressure, heat, temperature, or the like, and is particularly intended for use in connection'with apparatus requiring very close control and is designed to 0perate on a low differential of pressure or temperature. However, certain features of the invention may be adapted for general use other than for such particular purposes. Devices of this kind are adapted for use in connection withchemical processes, control of the temperature of rooms, for refrigerators or cooling apparatus and for other purposes which will be apparent from a description of the same.

The objects of the invention are to provide an improved controlling apparatus of the character indicated; to provide a controlling apparatus which will be particularly sensitive and which will be eiective in providing for close control of pressure temperature or the like; to provide an improved electric switch with novel means for actuating the same; to provide an electric switch having a floating contact adapted to coact with iiXed contacts; to provide a switch having a movable member having a substantially rectangular movement; to provide a switch having a movable contact coacting withl fined contacts; to provide a plurality of making and breaking points; to provide differential resistance or tension for certain operating parts; and to provide such novel features, adjustments and advantages as will appear from the following description.

In the accompanying drawings illustrating this invention;

,Figure l is a vertical sectional view with the switch shown in open posit-ion and taken substantially on the line 1-1 of Figure 2;

Figure 2 is a sectional view taken on the line 2 2 of Figure 1;

Figure .3 is a sectional view taken on the line 3-3 of Figure 1;

Serial No. 540,709.

Figure 4 is a cross section taken on the line 4--4 of Figure l;

Figure 5 is a cross section taken on the line 5-5 of Figure 1; and

Figures 6, 7 8, and 9 are diagrammatic 50 views illustrating the operation of the controller. I

The operating parts are preferably mounted in a boX or casing 10 which for convenience may have a vacuum or pressure chamber 11 65 secured directly thereto by means of bolts 12. A bellows or expansible member 13 is arranged in the pressure chamber and has a disc 14 to which is attached a threaded lug 15 which is engaged by the threaded stem on' an adjustable point or thrust member 16. The point or thrust member coacts with the controlling switch but any other suitable pressure actuated means may be used for this purpose. 55

The point 17 of the pressure member 16 engages with a toggle arm'18 which is pivoted at 19 to a bracket 20 in the casing l0. The free end of the arm 18 coacts wlth a second toggle arm 2l whichis pivoted to a swinging bracket or support 22. Tension springs 23 are secured to the swinging bracket or support 22 and the pivot pin 19 and tend to resist the upward movement of the toggle arms. The tension on the springsl which increases as the springs are stretched, is compensated by the toggle action as the toggle members move upwardly so that a variable resistance is provided at the point 17. The bellows may be of spring type or have a380 spring coact therewith and the action of the toggle in connection with the springs 23 serves to compensate for the increase or decrease in tension due to the action or movement of the bellows. f 85 A movable bearing or roller 24 rests on the upper face of the arm 18 and is pivoted to an adjusting screw 25 which extends out through the side of the box and is engaged by a nut 26 which is rotatably mounted in the side of the box so that it cannot move longitudinally. As the nut 26 is turned, the roller or bearing 24 will move along the surface of the arm 18. This roller also engagesa second arm 27 which is pivoted at 28 in brackets 29. It will be seen that as the roller 24 is moved inwardly or outwardly, the leverage is varied Y so that greater or less force is needed to swing lever 34 is swung. A spring 48 is secured at 49 to oneside of vthe frame 38 andits upper end'projects inwardly to engage with the back of the lever 34, as shown in Figure 1. The pressure of the arm 27 against a relatively fixed resistance.

The lever 27 is provided with a knife edge or bearing 30which rests on the upper surface .thereof and which has 'a tang 31 that engages with a hole 32 in the top of the lever. The knife edge engages with notches or bearings 33 in the sides ofa swinging bracket or bell crank lever 34 which is substantially U-shaped in cross section. Thev `lower arms 35 of this lever are provided with holes or bearings 36 for engaging with a knife edged fulcrum 37v which Vis rigidly secured to one side of a sub-frame 38 which is mounted in the box 10.A f j Tension springs 39- are connected at one end Itoears 40on the arms 35 and .at the opposite end to ears 41 on the upper end Vof an overthrow orA toggle arm 42 which 1s bent atl its lower end to provide a socket or bearingf43 which is pivoted on a lip or projection 44 iwhichf extends Ainwardly from the side of the` sub-frame 38. The .upperearms ofthe `lever 34 are provided with bearings 45 for .receiving projections on a substantially H- shaped plate lor arm y46, the yopposite end of kwhich engages with the arm 42-and is provided Ywith a tang 47v thatts Vfreely ina hole in said plate to hold the parts together. This overthrow or toggle arrangement is also for the purpose ofproviding a substantially uniform tension or pull on` the springs as the this spring against the lever 34 may be adjusted by means fof `an-adjusting screw 50 which engages with a threaded holein the 1 side of the box 10 and which is provided with y alock nut V51.

' Ay switch actuating element or tongue 52 is also pivoted on the knife edge or bearing e 30. This tongue-or member has twoside bars 53 with notches .for engagementr withY the Vends of the bearing 30, these bars being connected by integrally formed cross pieces 54 and 55a H `A bifurcated swinging Varm-ortappet/V 56 is ,pivoted in notches 57 in the upper arms of the lever 34 and extends downwardly, the lower end being provided with projections 58 and .'59 which are spaced apart and which take overfand are adapted. to engage at times with the sides of the cross piece 55. .A spring 60 is connected at one end with the lower end tangs or .projections which engage with n holes 66 in the arms 61, these holes being somewhat larger than the tangs to permit the necessary'movement. From this descripe tion, it' willY be seen that the contact 62 is substantially a floating Contact.

The pivot or pin 64 carries avsleeve 67 of insulating material which fits between twol branches at the endv of a spring 'Contact or switch member 68 which is preferably formed integrally with a channel shaped plate 69 which ts in a groove-70 in a block of insulating material. 71 mounted inthe box 10.

`The plate 69 also vhas lanother integrally formed resilientswitch memberor contact 72 which 1s best seen in Figure 3. -A- main switch contact7 3 lits in the channel 69, these parts being ield together in any suitable way., 'and being provided withfa terminal or binding screw 74. Another contact plate or Schannel 75 isv mounted in agroove 76 in the block 71 and is provided .on the lower side with a yielding contact 77 which proj ectsoutwardly and is substantially of the same shape as the Contact 72. i The channel or terminal plate 75 also has another contact 78 which is adapt- Y ed to be engaged at times by the contact 68. A main contact or switch plate 7 9is secured in the channel or plate 75, these parts being provided with a terminal or binding screw `80v The operationV ofthe device may be best runderstood from Figurel taken in connection with Figures 6 to 9 inclusive. Figure 6 illustrates the position of the parts as shown .in Figure 1, at which time the switch is open and the pressure or temperature controlled element in normal or retracted position. As soon as sufficient pressure is exerted in the chamber 11`the point 17 is forced upwardly against the lever 18and tends to'swing this lever on the pivot 19 against the tension of the spring 23. lAls the spring is stretched, itsresistance is increasedbut Athis is compensated forby the toggle arrangement'of the arms 18 and 21 so lthat a variable resistt ance is provided for by this springto, compensate for the action ofthe bellows. The lever Y18 also Vtends to swin-gthe lever V27 through the medium of the adjustable fulcrum or connection 24which serves to increase or decrease the leverage or advantage of the lever 18 with respect. to the lever 27.

The knife edge or bearing 30 on the lever Vil 27 pushes up on the bell crank lever or swinging bracket 34 and tends to swing it on the fulcrum or pivot 37 against the tension of the springs 39. The brace or link 46 at the same time pushes the top of the arm 42.to the left thereby swinging the upper end over the pivot or dead center 44 which tends to make the tension uniform during the swinging movement of the bellcrank lever 34.

As the upper arms of the bell crank lever 34 moveto the left they carry the pivot 57 beyond the spring 60, as shown in Figure 7. As soon as the pivot 57 passes the dead center it pulls the lower end of the swinging arm and striking member 56 to the right as shown in Figure 7 until the projection 58 strikes the cross piece on the switch actuating element or tongue 52. This movement permits the lower end of the spring to move past the tongue 52 thereby swinging the top of the tongue to the right or to the position shown in Figure 8. This gives a snap action or quick make or closure for the switch contact member 62. The striking of the projection 58 on the tongue tends to make the action more positive and to insure the proper actuation of the switch.

rThe actuation of the switch will presently be described but the switch remains closed as long as the pressure in the chamber 11 is suflicient to hold the lever 18 and connected parts in the operative position just described. As soon as the pressure decreases the point 17 lowers and the tendency is to return the various levers and parts to normal position. As soon as the lever 27 moves downwardly, the pivot 57 of the swinging arm 56 again moves to the right until it passes the center line of the spring 60 at which time the spring tends to pull the lower end of the arm 56 to the left or until the projection 59 strikes the swinging tongue 52 which prevents further free movement. This however, causes the lower end of the spring to pass the tongue and to pull the upper end of the tongue to the yleft or to initial position, as shown in Figure 6, with the contact 62 resting against a suitable stop or abutment 81 on the lblock 71.

While such swinging movements are taking place it will also be noted that the lowering of the pivot 33 permits a corresponding downward movement of the contact 62 before it is swung out of closed position. The effect of this is such that the contact 62 moves through a substantially rectangular path or orbit. In other words, starting from initial position it first slides up along the abutment 8l, then swings to the right until it strikes the `main contacts 73 and 79, then moves down across the face of these contacts and then swings back toits initial position.

fhen the swinging tongue 52 moves upwardly it carries the roller or insulatedv pin 67 up so that the forked end of the switch member 68 is carried up and the end of the member isso shaped that when the sleeve 67 moves toward switch closing position, the contact 68 engages with the fixed contact 78 just before the contact 62 closes against the main contacts 73 and 79. The closing of this auxiliary switch tends to prevent any arcing between the main switch contacts.

When the switch is opened the arms of the contact 62 slide down over the faces of the main contacts 73 and 79 and press againstV the auxiliary spring contacts 72 and 77 which project for some distance beyond the main contacts. The arms of the contact 62 are thus pressed against the yielding or auxiliary contacts until after they are disengaged from the main fixed contacts and the final opening action is the slipping of the arms off from these yielding contacts so that the final break occurs between the moving contact and these yielding auxiliary contacts which prevents arcing between the main contact members. It will also be understood that the spring contact 68 is disengaged from the contact 78 before this final movement occurs. Due to the tripping action of the switch actuating mechanism, the movement of the branches of the contact 62 off from the spring contacts 72 and 77 is exceedingly rapid or instantaneous so that there' is little possibility of objectionable arcing at these points when the circuit is broken. It will of course be understood that the terminals or binding posts 74 and 80 are connected in any suitable circuit which is to be controlled by the switch.

The amount of pressure required for operating the switch, or the sensitivity of the same may be regulated by the adjusting screw 50 which coacts with the spring 48 for adjusting the resistance or variation in pressure required for swinging the bell crank lever 34. The drawings show the contacts so arranged that the switch moves to on position on a decrease of pressure in the chamber 11, but it is obvious that the contacts may be so mounted that the switch will move to on position by an increase in the pressure in chamber 11.

From this description it will be apparent that my controlling device may be utilized for different purposes and it will also be noted that modifications may be made in order to adapt it for different conditions and some of the features may be utilized without incorporating the entire mechanism and therefore I do not wish to be limited to the lexact structure shown and described except as specified in the following claims in which I claim.

1. In an apparatus of the character set forth, the combination of an actuating mem` ber having a bearing thereon, a bell crank lever engaging with said bearing and a ful- `crum adjacent thereto, a spring tending to 'swing the bell crank lever around on its' fulcrum, a vibrating tongue pivoted on said bearing, a swinging lever pivoted to the bell crank lever and having spaced apart tappets adapted to engage with the vibrating tongue, a spring connecting the upper end of the vibrating tongue with the lower end of the swinging lever and means for limiting the swinging movement of the upper end of the vibrating tongue, the arrangement being such that when the bearing is raised it will swing the bell crank lever and cause the last named spring to swing the swinging lever and to cooperatev therewith to yswing the yvibrating tongue.

2. A device as per claim 1in which one end of the first named spring is attached to a support which moves therewith so that'the rotative force againstthe lever will be substantially uniform as the lever is swung.

- 3. In a device of the character set forth, the. combination of a bell crank lever having a fulcrum at approximately the center yof the lowerl part thereof', a `bearing engaging with theV lever at one side of the fulcrum and adapted to actuate the lever, a spring connected with the lever at-the opposite vside of the fulcrum, a swinging arm pivoted adjacent to the lever kand connected at oneend with the spring, a link connecting the upper end of the arm with the upper portion of the lever, a vibrating element pivoted adjacent the lower end of the bell crank lever and movable therewith, a swinging arm pivoted to the upper portion of the bell crank lever and having projections adapted to .engage with opposite ysides of the vibrating element when the lever is swung, a spring connecting the .lower end of the swinging lever with the upper yportion of the vibrating element, and means for limiting the swinging movement of the upper end of the vibrating element, the arrangement being such that when the bearing is raised the bell crank lever will be swung on its pivot and the last named spring and the swinging lever will coac-t to swing the vibrating element in one direction, and when the bearing is lowered, said spring and lever will swing the element in the oppositedirection. f

A device as per claim 3 having an adjustable spring mounted adjacent to the bell crank lever and tending to resist the move- .ment of the bell crank lever 1n one direction.

tongue whereby the free end of the vibrating tongue will have a reciprocatory and vibratory movement. f

6. The combination ofA a main levermeans for operating said lever, a `secondary lever pivoted to said main lever, a vibrating tongue loperatively connected with the main lever and adapted to move longitudinally when the lever vis swung, a spring connected with said secondary ylever and with said'tongue, said levers beingso arrangedthata movement of the main lever will swing the pivot of the secondary lever and cause the secondary lever to be tripped by said spring and strike the vibrating tongue and also topermit the spring to swing said tongue whereby the free end of the tongue will have a compound movement.

- 7. In a controlling apparatus, the combination ofan electric switch having a closing member adapted to move through a limited path, an actuating lever carrying said closing member, a swinging bracket, anwarm pivoted to the swinging bracket and adapted to engage with the -actuating lever to swing the same, a springbetween theactuating lever and the swinging arm for moving the lever when the pivot thereof passes the Idead center, yielding means 'tending to hold the bracket in normalposition, a lever pivoted adjacent to the bracket, a bearing on said lever supporting the actuating lever and engaging with the bracket, asecond lever pivoted adjacent to the last named lever, -a roller arranged between the last named levers, a screw :for adjusting said roller, ay spring coacting `with the last `named lever, and means adapted Vto coact with thelast named lever to actuate the same.

8.- The combination of a bell crank lever member, means for actuating said member to swing it on its fulcrum, a vibrating tongue memberoperatively connected to said bell Ycrank levermember and adapted to move vlongitudinally when th-e bell crank lever `member is swung, a secondary lever pivotally connectedto one of said first named members,

and a spring having one end connected t-o the free end of the Secondary lever,and the `other end connected to the other of said first named members, said parts `being arranged so that the movement of the bell crank lever member will.causethesecondary lever to be swung and tripped by the spring which in turn will cause the vibrating tongue t-o swing.

9. Thecombinationof a main lever, means for swinging said lever in one direction, means Jr`or swinging the'lever in the opposite direction, a secondary lever pivoted to sai-d Vmain4 lever, a vibrating tongue swingmgly connected with the main lever and adapted to km-ove longitudinally when the main lever swung, an'4 electric contact on said tongue ladapted to' coact with another contact, a

spring connected Vwith the secondary lever and said tongue, saidlevers being so arranged that a movement of the main lever will swing the pivots of the secondary lever which will be tripped by the spring, which in turn will vibrate the vibrating tongue whereby the free end of the vibrating tongue will have a reeiprooatory and vibrating movement, the path of movement of the connection between said spring and secondary lever being located in a zone intermediate the pivotal axis of said main lever and the path of movement of the pivotal axis of said secondary lever.

EMIL T. JOHNSSON.

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